update assimp to 5.2.3 Bugfix-Release

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation.cc

@@ -0,0 +1,54 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/animation/keyframe_animation.h"
+
+namespace draco {
+
+KeyframeAnimation::KeyframeAnimation() {}
+
+bool KeyframeAnimation::SetTimestamps(
+    const std::vector<TimestampType> &timestamp) {
+  // Already added attributes.
+  const int32_t num_frames = timestamp.size();
+  if (num_attributes() > 0) {
+    // Timestamp attribute could be added only once.
+    if (timestamps()->size()) {
+      return false;
+    } else {
+      // Check if the number of frames is consistent with
+      // the existing keyframes.
+      if (num_frames != num_points()) {
+        return false;
+      }
+    }
+  } else {
+    // This is the first attribute.
+    set_num_frames(num_frames);
+  }
+
+  // Add attribute for time stamp data.
+  std::unique_ptr<PointAttribute> timestamp_att =
+      std::unique_ptr<PointAttribute>(new PointAttribute());
+  timestamp_att->Init(GeometryAttribute::GENERIC, 1, DT_FLOAT32, false,
+                      num_frames);
+  for (PointIndex i(0); i < num_frames; ++i) {
+    timestamp_att->SetAttributeValue(timestamp_att->mapped_index(i),
+                                     &timestamp[i.value()]);
+  }
+  this->SetAttribute(kTimestampId, std::move(timestamp_att));
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation.h

@@ -0,0 +1,107 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ANIMATION_KEYFRAME_ANIMATION_H_
+#define DRACO_ANIMATION_KEYFRAME_ANIMATION_H_
+
+#include <vector>
+
+#include "draco/point_cloud/point_cloud.h"
+
+namespace draco {
+
+// Class for holding keyframe animation data. It will have two or more
+// attributes as a point cloud. The first attribute is always the timestamp
+// of the animation. Each KeyframeAnimation could have multiple animations with
+// the same number of frames. Each animation will be treated as a point
+// attribute.
+class KeyframeAnimation : public PointCloud {
+ public:
+  // Force time stamp to be float type.
+  using TimestampType = float;
+
+  KeyframeAnimation();
+
+  // Animation must have only one timestamp attribute.
+  // This function must be called before adding any animation data.
+  // Returns false if timestamp already exists.
+  bool SetTimestamps(const std::vector<TimestampType> &timestamp);
+
+  // Returns an id for the added animation data. This id will be used to
+  // identify this animation.
+  // Returns -1 if error, e.g. number of frames is not consistent.
+  // Type |T| should be consistent with |DataType|, e.g:
+  //    float - DT_FLOAT32,
+  //    int32_t - DT_INT32, ...
+  template <typename T>
+  int32_t AddKeyframes(DataType data_type, uint32_t num_components,
+                       const std::vector<T> &data);
+
+  const PointAttribute *timestamps() const {
+    return GetAttributeByUniqueId(kTimestampId);
+  }
+  const PointAttribute *keyframes(int32_t animation_id) const {
+    return GetAttributeByUniqueId(animation_id);
+  }
+
+  // Number of frames should be equal to number points in the point cloud.
+  void set_num_frames(int32_t num_frames) { set_num_points(num_frames); }
+  int32_t num_frames() const { return static_cast<int32_t>(num_points()); }
+
+  int32_t num_animations() const { return num_attributes() - 1; }
+
+ private:
+  // Attribute id of timestamp is fixed to 0.
+  static constexpr int32_t kTimestampId = 0;
+};
+
+template <typename T>
+int32_t KeyframeAnimation::AddKeyframes(DataType data_type,
+                                        uint32_t num_components,
+                                        const std::vector<T> &data) {
+  // TODO(draco-eng): Verify T is consistent with |data_type|.
+  if (num_components == 0) {
+    return -1;
+  }
+  // If timestamps is not added yet, then reserve attribute 0 for timestamps.
+  if (!num_attributes()) {
+    // Add a temporary attribute with 0 points to fill attribute id 0.
+    std::unique_ptr<PointAttribute> temp_att =
+        std::unique_ptr<PointAttribute>(new PointAttribute());
+    temp_att->Init(GeometryAttribute::GENERIC, num_components, data_type, false,
+                   0);
+    this->AddAttribute(std::move(temp_att));
+
+    set_num_frames(data.size() / num_components);
+  }
+
+  if (data.size() != num_components * num_frames()) {
+    return -1;
+  }
+
+  std::unique_ptr<PointAttribute> keyframe_att =
+      std::unique_ptr<PointAttribute>(new PointAttribute());
+  keyframe_att->Init(GeometryAttribute::GENERIC, num_components, data_type,
+                     false, num_frames());
+  const size_t stride = num_components;
+  for (PointIndex i(0); i < num_frames(); ++i) {
+    keyframe_att->SetAttributeValue(keyframe_att->mapped_index(i),
+                                    &data[i.value() * stride]);
+  }
+  return this->AddAttribute(std::move(keyframe_att));
+}
+
+}  // namespace draco
+
+#endif  // DRACO_ANIMATION_KEYFRAME_ANIMATION_H_

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_decoder.cc

@@ -0,0 +1,30 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/animation/keyframe_animation_decoder.h"
+
+namespace draco {
+
+Status KeyframeAnimationDecoder::Decode(const DecoderOptions &options,
+                                        DecoderBuffer *in_buffer,
+                                        KeyframeAnimation *animation) {
+  const auto status = PointCloudSequentialDecoder::Decode(
+      options, in_buffer, static_cast<PointCloud *>(animation));
+  if (!status.ok()) {
+    return status;
+  }
+  return OkStatus();
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_decoder.h

@@ -0,0 +1,34 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ANIMATION_KEYFRAME_ANIMATION_DECODER_H_
+#define DRACO_ANIMATION_KEYFRAME_ANIMATION_DECODER_H_
+
+#include "draco/animation/keyframe_animation.h"
+#include "draco/compression/point_cloud/point_cloud_sequential_decoder.h"
+
+namespace draco {
+
+// Class for decoding keyframe animation.
+class KeyframeAnimationDecoder : private PointCloudSequentialDecoder {
+ public:
+  KeyframeAnimationDecoder(){};
+
+  Status Decode(const DecoderOptions &options, DecoderBuffer *in_buffer,
+                KeyframeAnimation *animation);
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ANIMATION_KEYFRAME_ANIMATION_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_encoder.cc

@@ -0,0 +1,28 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/animation/keyframe_animation_encoder.h"
+
+namespace draco {
+
+KeyframeAnimationEncoder::KeyframeAnimationEncoder() {}
+
+Status KeyframeAnimationEncoder::EncodeKeyframeAnimation(
+    const KeyframeAnimation &animation, const EncoderOptions &options,
+    EncoderBuffer *out_buffer) {
+  SetPointCloud(animation);
+  return Encode(options, out_buffer);
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_encoder.h

@@ -0,0 +1,39 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ANIMATION_KEYFRAME_ANIMATION_ENCODER_H_
+#define DRACO_ANIMATION_KEYFRAME_ANIMATION_ENCODER_H_
+
+#include "draco/animation/keyframe_animation.h"
+#include "draco/compression/point_cloud/point_cloud_sequential_encoder.h"
+
+namespace draco {
+
+// Class for encoding keyframe animation. It takes KeyframeAnimation as a
+// PointCloud and compress it. It's mostly a wrapper around PointCloudEncoder so
+// that the animation module could be separated from geometry compression when
+// exposed to developers.
+class KeyframeAnimationEncoder : private PointCloudSequentialEncoder {
+ public:
+  KeyframeAnimationEncoder();
+
+  // Encode an animation to a buffer.
+  Status EncodeKeyframeAnimation(const KeyframeAnimation &animation,
+                                 const EncoderOptions &options,
+                                 EncoderBuffer *out_buffer);
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ANIMATION_KEYFRAME_ANIMATION_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_encoding_test.cc

@@ -0,0 +1,168 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/animation/keyframe_animation.h"
+#include "draco/animation/keyframe_animation_decoder.h"
+#include "draco/animation/keyframe_animation_encoder.h"
+#include "draco/core/draco_test_base.h"
+#include "draco/core/draco_test_utils.h"
+
+namespace draco {
+
+class KeyframeAnimationEncodingTest : public ::testing::Test {
+ protected:
+  KeyframeAnimationEncodingTest() {}
+
+  bool CreateAndAddTimestamps(int32_t num_frames) {
+    timestamps_.resize(num_frames);
+    for (int i = 0; i < timestamps_.size(); ++i)
+      timestamps_[i] = static_cast<draco::KeyframeAnimation::TimestampType>(i);
+    return keyframe_animation_.SetTimestamps(timestamps_);
+  }
+
+  int32_t CreateAndAddAnimationData(int32_t num_frames,
+                                    uint32_t num_components) {
+    // Create and add animation data with.
+    animation_data_.resize(num_frames * num_components);
+    for (int i = 0; i < animation_data_.size(); ++i)
+      animation_data_[i] = static_cast<float>(i);
+    return keyframe_animation_.AddKeyframes(draco::DT_FLOAT32, num_components,
+                                            animation_data_);
+  }
+
+  template <int num_components_t>
+  void CompareAnimationData(const KeyframeAnimation &animation0,
+                            const KeyframeAnimation &animation1,
+                            bool quantized) {
+    ASSERT_EQ(animation0.num_frames(), animation1.num_frames());
+    ASSERT_EQ(animation0.num_animations(), animation1.num_animations());
+
+    if (quantized) {
+      // TODO(hemmer) : Add test for stable quantization.
+      // Quantization will result in slightly different values.
+      // Skip comparing values.
+      return;
+    }
+
+    // Compare time stamp.
+    const auto timestamp_att0 = animation0.timestamps();
+    const auto timestamp_att1 = animation0.timestamps();
+    for (int i = 0; i < animation0.num_frames(); ++i) {
+      std::array<float, 1> att_value0;
+      std::array<float, 1> att_value1;
+      ASSERT_TRUE((timestamp_att0->GetValue<float, 1>(
+          draco::AttributeValueIndex(i), &att_value0)));
+      ASSERT_TRUE((timestamp_att1->GetValue<float, 1>(
+          draco::AttributeValueIndex(i), &att_value1)));
+      ASSERT_FLOAT_EQ(att_value0[0], att_value1[0]);
+    }
+
+    for (int animation_id = 1; animation_id < animation0.num_animations();
+         ++animation_id) {
+      // Compare keyframe data.
+      const auto keyframe_att0 = animation0.keyframes(animation_id);
+      const auto keyframe_att1 = animation1.keyframes(animation_id);
+      ASSERT_EQ(keyframe_att0->num_components(),
+                keyframe_att1->num_components());
+      for (int i = 0; i < animation0.num_frames(); ++i) {
+        std::array<float, num_components_t> att_value0;
+        std::array<float, num_components_t> att_value1;
+        ASSERT_TRUE((keyframe_att0->GetValue<float, num_components_t>(
+            draco::AttributeValueIndex(i), &att_value0)));
+        ASSERT_TRUE((keyframe_att1->GetValue<float, num_components_t>(
+            draco::AttributeValueIndex(i), &att_value1)));
+        for (int j = 0; j < att_value0.size(); ++j) {
+          ASSERT_FLOAT_EQ(att_value0[j], att_value1[j]);
+        }
+      }
+    }
+  }
+
+  template <int num_components_t>
+  void TestKeyframeAnimationEncoding() {
+    TestKeyframeAnimationEncoding<num_components_t>(false);
+  }
+
+  template <int num_components_t>
+  void TestKeyframeAnimationEncoding(bool quantized) {
+    // Encode animation class.
+    draco::EncoderBuffer buffer;
+    draco::KeyframeAnimationEncoder encoder;
+    EncoderOptions options = EncoderOptions::CreateDefaultOptions();
+    if (quantized) {
+      // Set quantization for timestamps.
+      options.SetAttributeInt(0, "quantization_bits", 20);
+      // Set quantization for keyframes.
+      for (int i = 1; i <= keyframe_animation_.num_animations(); ++i) {
+        options.SetAttributeInt(i, "quantization_bits", 20);
+      }
+    }
+
+    ASSERT_TRUE(
+        encoder.EncodeKeyframeAnimation(keyframe_animation_, options, &buffer)
+            .ok());
+
+    draco::DecoderBuffer dec_decoder;
+    draco::KeyframeAnimationDecoder decoder;
+    DecoderBuffer dec_buffer;
+    dec_buffer.Init(buffer.data(), buffer.size());
+
+    // Decode animation class.
+    std::unique_ptr<KeyframeAnimation> decoded_animation(
+        new KeyframeAnimation());
+    DecoderOptions dec_options;
+    ASSERT_TRUE(
+        decoder.Decode(dec_options, &dec_buffer, decoded_animation.get()).ok());
+
+    // Verify if animation before and after compression is identical.
+    CompareAnimationData<num_components_t>(keyframe_animation_,
+                                           *decoded_animation, quantized);
+  }
+
+  draco::KeyframeAnimation keyframe_animation_;
+  std::vector<draco::KeyframeAnimation::TimestampType> timestamps_;
+  std::vector<float> animation_data_;
+};
+
+TEST_F(KeyframeAnimationEncodingTest, OneComponent) {
+  const int num_frames = 1;
+  ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 1), 1);
+  TestKeyframeAnimationEncoding<1>();
+}
+
+TEST_F(KeyframeAnimationEncodingTest, ManyComponents) {
+  const int num_frames = 100;
+  ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 100), 1);
+  TestKeyframeAnimationEncoding<100>();
+}
+
+TEST_F(KeyframeAnimationEncodingTest, ManyComponentsWithQuantization) {
+  const int num_frames = 100;
+  ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 4), 1);
+  // Test compression with quantization.
+  TestKeyframeAnimationEncoding<4>(true);
+}
+
+TEST_F(KeyframeAnimationEncodingTest, MultipleAnimations) {
+  const int num_frames = 5;
+  ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 3), 1);
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 3), 2);
+  TestKeyframeAnimationEncoding<3>();
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/animation/keyframe_animation_test.cc

@@ -0,0 +1,102 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/animation/keyframe_animation.h"
+
+#include "draco/core/draco_test_base.h"
+
+namespace {
+
+class KeyframeAnimationTest : public ::testing::Test {
+ protected:
+  KeyframeAnimationTest() {}
+
+  bool CreateAndAddTimestamps(int32_t num_frames) {
+    timestamps_.resize(num_frames);
+    for (int i = 0; i < timestamps_.size(); ++i)
+      timestamps_[i] = static_cast<draco::KeyframeAnimation::TimestampType>(i);
+    return keyframe_animation_.SetTimestamps(timestamps_);
+  }
+
+  int32_t CreateAndAddAnimationData(int32_t num_frames,
+                                    uint32_t num_components) {
+    // Create and add animation data with.
+    animation_data_.resize(num_frames * num_components);
+    for (int i = 0; i < animation_data_.size(); ++i)
+      animation_data_[i] = static_cast<float>(i);
+    return keyframe_animation_.AddKeyframes(draco::DT_FLOAT32, num_components,
+                                            animation_data_);
+  }
+
+  template <int num_components_t>
+  void CompareAnimationData() {
+    // Compare time stamp.
+    const auto timestamp_att = keyframe_animation_.timestamps();
+    for (int i = 0; i < timestamps_.size(); ++i) {
+      std::array<float, 1> att_value;
+      ASSERT_TRUE((timestamp_att->GetValue<float, 1>(
+          draco::AttributeValueIndex(i), &att_value)));
+      ASSERT_FLOAT_EQ(att_value[0], i);
+    }
+
+    // Compare keyframe data.
+    const auto keyframe_att = keyframe_animation_.keyframes(1);
+    for (int i = 0; i < animation_data_.size() / num_components_t; ++i) {
+      std::array<float, num_components_t> att_value;
+      ASSERT_TRUE((keyframe_att->GetValue<float, num_components_t>(
+          draco::AttributeValueIndex(i), &att_value)));
+      for (int j = 0; j < num_components_t; ++j) {
+        ASSERT_FLOAT_EQ(att_value[j], i * num_components_t + j);
+      }
+    }
+  }
+
+  template <int num_components_t>
+  void TestKeyframeAnimation(int32_t num_frames) {
+    ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+    ASSERT_EQ(CreateAndAddAnimationData(num_frames, num_components_t), 1);
+    CompareAnimationData<num_components_t>();
+  }
+
+  draco::KeyframeAnimation keyframe_animation_;
+  std::vector<draco::KeyframeAnimation::TimestampType> timestamps_;
+  std::vector<float> animation_data_;
+};
+
+// Test animation with 1 component and 10 frames.
+TEST_F(KeyframeAnimationTest, OneComponent) { TestKeyframeAnimation<1>(10); }
+
+// Test animation with 4 component and 10 frames.
+TEST_F(KeyframeAnimationTest, FourComponent) { TestKeyframeAnimation<4>(10); }
+
+// Test adding animation data before timestamp.
+TEST_F(KeyframeAnimationTest, AddingAnimationFirst) {
+  ASSERT_EQ(CreateAndAddAnimationData(5, 1), 1);
+  ASSERT_TRUE(CreateAndAddTimestamps(5));
+}
+
+// Test adding timestamp more than once.
+TEST_F(KeyframeAnimationTest, ErrorAddingTimestampsTwice) {
+  ASSERT_TRUE(CreateAndAddTimestamps(5));
+  ASSERT_FALSE(CreateAndAddTimestamps(5));
+}
+// Test animation with multiple animation data.
+TEST_F(KeyframeAnimationTest, MultipleAnimationData) {
+  const int num_frames = 5;
+  ASSERT_TRUE(CreateAndAddTimestamps(num_frames));
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 1), 1);
+  ASSERT_EQ(CreateAndAddAnimationData(num_frames, 2), 2);
+}
+
+}  // namespace

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_octahedron_transform.cc

@@ -0,0 +1,145 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "draco/attributes/attribute_octahedron_transform.h"
+
+#include "draco/attributes/attribute_transform_type.h"
+#include "draco/compression/attributes/normal_compression_utils.h"
+
+namespace draco {
+
+bool AttributeOctahedronTransform::InitFromAttribute(
+    const PointAttribute &attribute) {
+  const AttributeTransformData *const transform_data =
+      attribute.GetAttributeTransformData();
+  if (!transform_data ||
+      transform_data->transform_type() != ATTRIBUTE_OCTAHEDRON_TRANSFORM) {
+    return false;  // Wrong transform type.
+  }
+  quantization_bits_ = transform_data->GetParameterValue<int32_t>(0);
+  return true;
+}
+
+void AttributeOctahedronTransform::CopyToAttributeTransformData(
+    AttributeTransformData *out_data) const {
+  out_data->set_transform_type(ATTRIBUTE_OCTAHEDRON_TRANSFORM);
+  out_data->AppendParameterValue(quantization_bits_);
+}
+
+bool AttributeOctahedronTransform::TransformAttribute(
+    const PointAttribute &attribute, const std::vector<PointIndex> &point_ids,
+    PointAttribute *target_attribute) {
+  return GeneratePortableAttribute(attribute, point_ids,
+                                   target_attribute->size(), target_attribute);
+}
+
+bool AttributeOctahedronTransform::InverseTransformAttribute(
+    const PointAttribute &attribute, PointAttribute *target_attribute) {
+  if (target_attribute->data_type() != DT_FLOAT32) {
+    return false;
+  }
+
+  const int num_points = target_attribute->size();
+  const int num_components = target_attribute->num_components();
+  if (num_components != 3) {
+    return false;
+  }
+  constexpr int kEntrySize = sizeof(float) * 3;
+  float att_val[3];
+  const int32_t *source_attribute_data = reinterpret_cast<const int32_t *>(
+      attribute.GetAddress(AttributeValueIndex(0)));
+  uint8_t *target_address =
+      target_attribute->GetAddress(AttributeValueIndex(0));
+  OctahedronToolBox octahedron_tool_box;
+  if (!octahedron_tool_box.SetQuantizationBits(quantization_bits_)) {
+    return false;
+  }
+  for (uint32_t i = 0; i < num_points; ++i) {
+    const int32_t s = *source_attribute_data++;
+    const int32_t t = *source_attribute_data++;
+    octahedron_tool_box.QuantizedOctahedralCoordsToUnitVector(s, t, att_val);
+
+    // Store the decoded floating point values into the attribute buffer.
+    std::memcpy(target_address, att_val, kEntrySize);
+    target_address += kEntrySize;
+  }
+  return true;
+}
+
+void AttributeOctahedronTransform::SetParameters(int quantization_bits) {
+  quantization_bits_ = quantization_bits;
+}
+
+bool AttributeOctahedronTransform::EncodeParameters(
+    EncoderBuffer *encoder_buffer) const {
+  if (is_initialized()) {
+    encoder_buffer->Encode(static_cast<uint8_t>(quantization_bits_));
+    return true;
+  }
+  return false;
+}
+
+bool AttributeOctahedronTransform::DecodeParameters(
+    const PointAttribute &attribute, DecoderBuffer *decoder_buffer) {
+  uint8_t quantization_bits;
+  if (!decoder_buffer->Decode(&quantization_bits)) {
+    return false;
+  }
+  quantization_bits_ = quantization_bits;
+  return true;
+}
+
+bool AttributeOctahedronTransform::GeneratePortableAttribute(
+    const PointAttribute &attribute, const std::vector<PointIndex> &point_ids,
+    int num_points, PointAttribute *target_attribute) const {
+  DRACO_DCHECK(is_initialized());
+
+  // Quantize all values in the order given by point_ids into portable
+  // attribute.
+  int32_t *const portable_attribute_data = reinterpret_cast<int32_t *>(
+      target_attribute->GetAddress(AttributeValueIndex(0)));
+  float att_val[3];
+  int32_t dst_index = 0;
+  OctahedronToolBox converter;
+  if (!converter.SetQuantizationBits(quantization_bits_)) {
+    return false;
+  }
+  if (!point_ids.empty()) {
+    for (uint32_t i = 0; i < point_ids.size(); ++i) {
+      const AttributeValueIndex att_val_id =
+          attribute.mapped_index(point_ids[i]);
+      attribute.GetValue(att_val_id, att_val);
+      // Encode the vector into a s and t octahedral coordinates.
+      int32_t s, t;
+      converter.FloatVectorToQuantizedOctahedralCoords(att_val, &s, &t);
+      portable_attribute_data[dst_index++] = s;
+      portable_attribute_data[dst_index++] = t;
+    }
+  } else {
+    for (PointIndex i(0); i < num_points; ++i) {
+      const AttributeValueIndex att_val_id = attribute.mapped_index(i);
+      attribute.GetValue(att_val_id, att_val);
+      // Encode the vector into a s and t octahedral coordinates.
+      int32_t s, t;
+      converter.FloatVectorToQuantizedOctahedralCoords(att_val, &s, &t);
+      portable_attribute_data[dst_index++] = s;
+      portable_attribute_data[dst_index++] = t;
+    }
+  }
+
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_octahedron_transform.h

@@ -0,0 +1,81 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef DRACO_ATTRIBUTES_ATTRIBUTE_OCTAHEDRON_TRANSFORM_H_
+#define DRACO_ATTRIBUTES_ATTRIBUTE_OCTAHEDRON_TRANSFORM_H_
+
+#include "draco/attributes/attribute_transform.h"
+#include "draco/attributes/point_attribute.h"
+#include "draco/core/encoder_buffer.h"
+
+namespace draco {
+
+// Attribute transform for attributes transformed to octahedral coordinates.
+class AttributeOctahedronTransform : public AttributeTransform {
+ public:
+  AttributeOctahedronTransform() : quantization_bits_(-1) {}
+
+  // Return attribute transform type.
+  AttributeTransformType Type() const override {
+    return ATTRIBUTE_OCTAHEDRON_TRANSFORM;
+  }
+  // Try to init transform from attribute.
+  bool InitFromAttribute(const PointAttribute &attribute) override;
+  // Copy parameter values into the provided AttributeTransformData instance.
+  void CopyToAttributeTransformData(
+      AttributeTransformData *out_data) const override;
+
+  bool TransformAttribute(const PointAttribute &attribute,
+                          const std::vector<PointIndex> &point_ids,
+                          PointAttribute *target_attribute) override;
+
+  bool InverseTransformAttribute(const PointAttribute &attribute,
+                                 PointAttribute *target_attribute) override;
+
+  // Set number of quantization bits.
+  void SetParameters(int quantization_bits);
+
+  // Encode relevant parameters into buffer.
+  bool EncodeParameters(EncoderBuffer *encoder_buffer) const override;
+
+  bool DecodeParameters(const PointAttribute &attribute,
+                        DecoderBuffer *decoder_buffer) override;
+
+  bool is_initialized() const { return quantization_bits_ != -1; }
+  int32_t quantization_bits() const { return quantization_bits_; }
+
+ protected:
+  DataType GetTransformedDataType(
+      const PointAttribute &attribute) const override {
+    return DT_UINT32;
+  }
+  int GetTransformedNumComponents(
+      const PointAttribute &attribute) const override {
+    return 2;
+  }
+
+  // Perform the actual transformation.
+  bool GeneratePortableAttribute(const PointAttribute &attribute,
+                                 const std::vector<PointIndex> &point_ids,
+                                 int num_points,
+                                 PointAttribute *target_attribute) const;
+
+ private:
+  int32_t quantization_bits_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_ATTRIBUTE_OCTAHEDRON_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_quantization_transform.cc

@@ -0,0 +1,260 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/attributes/attribute_quantization_transform.h"
+
+#include "draco/attributes/attribute_transform_type.h"
+#include "draco/core/quantization_utils.h"
+
+namespace draco {
+
+bool AttributeQuantizationTransform::InitFromAttribute(
+    const PointAttribute &attribute) {
+  const AttributeTransformData *const transform_data =
+      attribute.GetAttributeTransformData();
+  if (!transform_data ||
+      transform_data->transform_type() != ATTRIBUTE_QUANTIZATION_TRANSFORM) {
+    return false;  // Wrong transform type.
+  }
+  int32_t byte_offset = 0;
+  quantization_bits_ = transform_data->GetParameterValue<int32_t>(byte_offset);
+  byte_offset += 4;
+  min_values_.resize(attribute.num_components());
+  for (int i = 0; i < attribute.num_components(); ++i) {
+    min_values_[i] = transform_data->GetParameterValue<float>(byte_offset);
+    byte_offset += 4;
+  }
+  range_ = transform_data->GetParameterValue<float>(byte_offset);
+  return true;
+}
+
+// Copy parameter values into the provided AttributeTransformData instance.
+void AttributeQuantizationTransform::CopyToAttributeTransformData(
+    AttributeTransformData *out_data) const {
+  out_data->set_transform_type(ATTRIBUTE_QUANTIZATION_TRANSFORM);
+  out_data->AppendParameterValue(quantization_bits_);
+  for (int i = 0; i < min_values_.size(); ++i) {
+    out_data->AppendParameterValue(min_values_[i]);
+  }
+  out_data->AppendParameterValue(range_);
+}
+
+bool AttributeQuantizationTransform::TransformAttribute(
+    const PointAttribute &attribute, const std::vector<PointIndex> &point_ids,
+    PointAttribute *target_attribute) {
+  if (point_ids.empty()) {
+    GeneratePortableAttribute(attribute, target_attribute->size(),
+                              target_attribute);
+  } else {
+    GeneratePortableAttribute(attribute, point_ids, target_attribute->size(),
+                              target_attribute);
+  }
+  return true;
+}
+
+bool AttributeQuantizationTransform::InverseTransformAttribute(
+    const PointAttribute &attribute, PointAttribute *target_attribute) {
+  if (target_attribute->data_type() != DT_FLOAT32) {
+    return false;
+  }
+
+  // Convert all quantized values back to floats.
+  const int32_t max_quantized_value =
+      (1u << static_cast<uint32_t>(quantization_bits_)) - 1;
+  const int num_components = target_attribute->num_components();
+  const int entry_size = sizeof(float) * num_components;
+  const std::unique_ptr<float[]> att_val(new float[num_components]);
+  int quant_val_id = 0;
+  int out_byte_pos = 0;
+  Dequantizer dequantizer;
+  if (!dequantizer.Init(range_, max_quantized_value)) {
+    return false;
+  }
+  const int32_t *const source_attribute_data =
+      reinterpret_cast<const int32_t *>(
+          attribute.GetAddress(AttributeValueIndex(0)));
+
+  const int num_values = target_attribute->size();
+
+  for (uint32_t i = 0; i < num_values; ++i) {
+    for (int c = 0; c < num_components; ++c) {
+      float value =
+          dequantizer.DequantizeFloat(source_attribute_data[quant_val_id++]);
+      value = value + min_values_[c];
+      att_val[c] = value;
+    }
+    // Store the floating point value into the attribute buffer.
+    target_attribute->buffer()->Write(out_byte_pos, att_val.get(), entry_size);
+    out_byte_pos += entry_size;
+  }
+  return true;
+}
+
+bool AttributeQuantizationTransform::IsQuantizationValid(
+    int quantization_bits) {
+  // Currently we allow only up to 30 bit quantization.
+  return quantization_bits >= 1 && quantization_bits <= 30;
+}
+
+bool AttributeQuantizationTransform::SetParameters(int quantization_bits,
+                                                   const float *min_values,
+                                                   int num_components,
+                                                   float range) {
+  if (!IsQuantizationValid(quantization_bits)) {
+    return false;
+  }
+  quantization_bits_ = quantization_bits;
+  min_values_.assign(min_values, min_values + num_components);
+  range_ = range;
+  return true;
+}
+
+bool AttributeQuantizationTransform::ComputeParameters(
+    const PointAttribute &attribute, const int quantization_bits) {
+  if (quantization_bits_ != -1) {
+    return false;  // already initialized.
+  }
+  if (!IsQuantizationValid(quantization_bits)) {
+    return false;
+  }
+  quantization_bits_ = quantization_bits;
+
+  const int num_components = attribute.num_components();
+  range_ = 0.f;
+  min_values_ = std::vector<float>(num_components, 0.f);
+  const std::unique_ptr<float[]> max_values(new float[num_components]);
+  const std::unique_ptr<float[]> att_val(new float[num_components]);
+  // Compute minimum values and max value difference.
+  attribute.GetValue(AttributeValueIndex(0), att_val.get());
+  attribute.GetValue(AttributeValueIndex(0), min_values_.data());
+  attribute.GetValue(AttributeValueIndex(0), max_values.get());
+
+  for (AttributeValueIndex i(1); i < static_cast<uint32_t>(attribute.size());
+       ++i) {
+    attribute.GetValue(i, att_val.get());
+    for (int c = 0; c < num_components; ++c) {
+      if (min_values_[c] > att_val[c]) {
+        min_values_[c] = att_val[c];
+      }
+      if (max_values[c] < att_val[c]) {
+        max_values[c] = att_val[c];
+      }
+    }
+  }
+  for (int c = 0; c < num_components; ++c) {
+    if (std::isnan(min_values_[c]) || std::isinf(min_values_[c]) ||
+        std::isnan(max_values[c]) || std::isinf(max_values[c])) {
+      return false;
+    }
+    const float dif = max_values[c] - min_values_[c];
+    if (dif > range_) {
+      range_ = dif;
+    }
+  }
+
+  // In case all values are the same, initialize the range to unit length. This
+  // will ensure that all values are quantized properly to the same value.
+  if (range_ == 0.f) {
+    range_ = 1.f;
+  }
+
+  return true;
+}
+
+bool AttributeQuantizationTransform::EncodeParameters(
+    EncoderBuffer *encoder_buffer) const {
+  if (is_initialized()) {
+    encoder_buffer->Encode(min_values_.data(),
+                           sizeof(float) * min_values_.size());
+    encoder_buffer->Encode(range_);
+    encoder_buffer->Encode(static_cast<uint8_t>(quantization_bits_));
+    return true;
+  }
+  return false;
+}
+
+bool AttributeQuantizationTransform::DecodeParameters(
+    const PointAttribute &attribute, DecoderBuffer *decoder_buffer) {
+  min_values_.resize(attribute.num_components());
+  if (!decoder_buffer->Decode(&min_values_[0],
+                              sizeof(float) * min_values_.size())) {
+    return false;
+  }
+  if (!decoder_buffer->Decode(&range_)) {
+    return false;
+  }
+  uint8_t quantization_bits;
+  if (!decoder_buffer->Decode(&quantization_bits)) {
+    return false;
+  }
+  if (!IsQuantizationValid(quantization_bits)) {
+    return false;
+  }
+  quantization_bits_ = quantization_bits;
+  return true;
+}
+
+void AttributeQuantizationTransform::GeneratePortableAttribute(
+    const PointAttribute &attribute, int num_points,
+    PointAttribute *target_attribute) const {
+  DRACO_DCHECK(is_initialized());
+
+  const int num_components = attribute.num_components();
+
+  // Quantize all values using the order given by point_ids.
+  int32_t *const portable_attribute_data = reinterpret_cast<int32_t *>(
+      target_attribute->GetAddress(AttributeValueIndex(0)));
+  const uint32_t max_quantized_value = (1 << (quantization_bits_)) - 1;
+  Quantizer quantizer;
+  quantizer.Init(range(), max_quantized_value);
+  int32_t dst_index = 0;
+  const std::unique_ptr<float[]> att_val(new float[num_components]);
+  for (PointIndex i(0); i < num_points; ++i) {
+    const AttributeValueIndex att_val_id = attribute.mapped_index(i);
+    attribute.GetValue(att_val_id, att_val.get());
+    for (int c = 0; c < num_components; ++c) {
+      const float value = (att_val[c] - min_values()[c]);
+      const int32_t q_val = quantizer.QuantizeFloat(value);
+      portable_attribute_data[dst_index++] = q_val;
+    }
+  }
+}
+
+void AttributeQuantizationTransform::GeneratePortableAttribute(
+    const PointAttribute &attribute, const std::vector<PointIndex> &point_ids,
+    int num_points, PointAttribute *target_attribute) const {
+  DRACO_DCHECK(is_initialized());
+
+  const int num_components = attribute.num_components();
+
+  // Quantize all values using the order given by point_ids.
+  int32_t *const portable_attribute_data = reinterpret_cast<int32_t *>(
+      target_attribute->GetAddress(AttributeValueIndex(0)));
+  const uint32_t max_quantized_value = (1 << (quantization_bits_)) - 1;
+  Quantizer quantizer;
+  quantizer.Init(range(), max_quantized_value);
+  int32_t dst_index = 0;
+  const std::unique_ptr<float[]> att_val(new float[num_components]);
+  for (uint32_t i = 0; i < point_ids.size(); ++i) {
+    const AttributeValueIndex att_val_id = attribute.mapped_index(point_ids[i]);
+    attribute.GetValue(att_val_id, att_val.get());
+    for (int c = 0; c < num_components; ++c) {
+      const float value = (att_val[c] - min_values()[c]);
+      const int32_t q_val = quantizer.QuantizeFloat(value);
+      portable_attribute_data[dst_index++] = q_val;
+    }
+  }
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_quantization_transform.h

@@ -0,0 +1,102 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_ATTRIBUTE_QUANTIZATION_TRANSFORM_H_
+#define DRACO_ATTRIBUTES_ATTRIBUTE_QUANTIZATION_TRANSFORM_H_
+
+#include <vector>
+
+#include "draco/attributes/attribute_transform.h"
+#include "draco/attributes/point_attribute.h"
+#include "draco/core/encoder_buffer.h"
+
+namespace draco {
+
+// Attribute transform for quantized attributes.
+class AttributeQuantizationTransform : public AttributeTransform {
+ public:
+  AttributeQuantizationTransform() : quantization_bits_(-1), range_(0.f) {}
+  // Return attribute transform type.
+  AttributeTransformType Type() const override {
+    return ATTRIBUTE_QUANTIZATION_TRANSFORM;
+  }
+  // Try to init transform from attribute.
+  bool InitFromAttribute(const PointAttribute &attribute) override;
+  // Copy parameter values into the provided AttributeTransformData instance.
+  void CopyToAttributeTransformData(
+      AttributeTransformData *out_data) const override;
+
+  bool TransformAttribute(const PointAttribute &attribute,
+                          const std::vector<PointIndex> &point_ids,
+                          PointAttribute *target_attribute) override;
+
+  bool InverseTransformAttribute(const PointAttribute &attribute,
+                                 PointAttribute *target_attribute) override;
+
+  bool SetParameters(int quantization_bits, const float *min_values,
+                     int num_components, float range);
+
+  bool ComputeParameters(const PointAttribute &attribute,
+                         const int quantization_bits);
+
+  // Encode relevant parameters into buffer.
+  bool EncodeParameters(EncoderBuffer *encoder_buffer) const override;
+
+  bool DecodeParameters(const PointAttribute &attribute,
+                        DecoderBuffer *decoder_buffer) override;
+
+  int32_t quantization_bits() const { return quantization_bits_; }
+  float min_value(int axis) const { return min_values_[axis]; }
+  const std::vector<float> &min_values() const { return min_values_; }
+  float range() const { return range_; }
+  bool is_initialized() const { return quantization_bits_ != -1; }
+
+ protected:
+  // Create portable attribute using 1:1 mapping between points in the input and
+  // output attribute.
+  void GeneratePortableAttribute(const PointAttribute &attribute,
+                                 int num_points,
+                                 PointAttribute *target_attribute) const;
+
+  // Create portable attribute using custom mapping between input and output
+  // points.
+  void GeneratePortableAttribute(const PointAttribute &attribute,
+                                 const std::vector<PointIndex> &point_ids,
+                                 int num_points,
+                                 PointAttribute *target_attribute) const;
+
+  DataType GetTransformedDataType(
+      const PointAttribute &attribute) const override {
+    return DT_UINT32;
+  }
+  int GetTransformedNumComponents(
+      const PointAttribute &attribute) const override {
+    return attribute.num_components();
+  }
+
+  static bool IsQuantizationValid(int quantization_bits);
+
+ private:
+  int32_t quantization_bits_;
+
+  // Minimal dequantized value for each component of the attribute.
+  std::vector<float> min_values_;
+
+  // Bounds of the dequantized attribute (max delta over all components).
+  float range_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTE_DEQUANTIZATION_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_transform.cc

@@ -0,0 +1,40 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/attributes/attribute_transform.h"
+
+namespace draco {
+
+bool AttributeTransform::TransferToAttribute(PointAttribute *attribute) const {
+  std::unique_ptr<AttributeTransformData> transform_data(
+      new AttributeTransformData());
+  this->CopyToAttributeTransformData(transform_data.get());
+  attribute->SetAttributeTransformData(std::move(transform_data));
+  return true;
+}
+
+std::unique_ptr<PointAttribute> AttributeTransform::InitTransformedAttribute(
+    const PointAttribute &src_attribute, int num_entries) {
+  const int num_components = GetTransformedNumComponents(src_attribute);
+  const DataType dt = GetTransformedDataType(src_attribute);
+  GeometryAttribute va;
+  va.Init(src_attribute.attribute_type(), nullptr, num_components, dt, false,
+          num_components * DataTypeLength(dt), 0);
+  std::unique_ptr<PointAttribute> transformed_attribute(new PointAttribute(va));
+  transformed_attribute->Reset(num_entries);
+  transformed_attribute->SetIdentityMapping();
+  return transformed_attribute;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_transform.h

@@ -0,0 +1,76 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_H_
+#define DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_H_
+
+#include "draco/attributes/attribute_transform_data.h"
+#include "draco/attributes/point_attribute.h"
+#include "draco/core/decoder_buffer.h"
+#include "draco/core/encoder_buffer.h"
+
+namespace draco {
+
+// Virtual base class for various attribute transforms, enforcing common
+// interface where possible.
+class AttributeTransform {
+ public:
+  virtual ~AttributeTransform() = default;
+
+  // Return attribute transform type.
+  virtual AttributeTransformType Type() const = 0;
+  // Try to init transform from attribute.
+  virtual bool InitFromAttribute(const PointAttribute &attribute) = 0;
+  // Copy parameter values into the provided AttributeTransformData instance.
+  virtual void CopyToAttributeTransformData(
+      AttributeTransformData *out_data) const = 0;
+  bool TransferToAttribute(PointAttribute *attribute) const;
+
+  // Applies the transform to |attribute| and stores the result in
+  // |target_attribute|. |point_ids| is an optional vector that can be used to
+  // remap values during the transform.
+  virtual bool TransformAttribute(const PointAttribute &attribute,
+                                  const std::vector<PointIndex> &point_ids,
+                                  PointAttribute *target_attribute) = 0;
+
+  // Applies an inverse transform to |attribute| and stores the result in
+  // |target_attribute|. In this case, |attribute| is an attribute that was
+  // already transformed (e.g. quantized) and |target_attribute| is the
+  // attribute before the transformation.
+  virtual bool InverseTransformAttribute(const PointAttribute &attribute,
+                                         PointAttribute *target_attribute) = 0;
+
+  // Encodes all data needed by the transformation into the |encoder_buffer|.
+  virtual bool EncodeParameters(EncoderBuffer *encoder_buffer) const = 0;
+
+  // Decodes all data needed to transform |attribute| back to the original
+  // format.
+  virtual bool DecodeParameters(const PointAttribute &attribute,
+                                DecoderBuffer *decoder_buffer) = 0;
+
+  // Initializes a transformed attribute that can be used as target in the
+  // TransformAttribute() function call.
+  virtual std::unique_ptr<PointAttribute> InitTransformedAttribute(
+      const PointAttribute &src_attribute, int num_entries);
+
+ protected:
+  virtual DataType GetTransformedDataType(
+      const PointAttribute &attribute) const = 0;
+  virtual int GetTransformedNumComponents(
+      const PointAttribute &attribute) const = 0;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_ATTRIBUTE_OCTAHEDRON_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_transform_data.h

@@ -0,0 +1,71 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_DATA_H_
+#define DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_DATA_H_
+
+#include <memory>
+
+#include "draco/attributes/attribute_transform_type.h"
+#include "draco/core/data_buffer.h"
+
+namespace draco {
+
+// Class for holding parameter values for an attribute transform of a
+// PointAttribute. This can be for example quantization data for an attribute
+// that holds quantized values. This class provides only a basic storage for
+// attribute transform parameters and it should be accessed only through wrapper
+// classes for a specific transform (e.g. AttributeQuantizationTransform).
+class AttributeTransformData {
+ public:
+  AttributeTransformData() : transform_type_(ATTRIBUTE_INVALID_TRANSFORM) {}
+  AttributeTransformData(const AttributeTransformData &data) = default;
+
+  // Returns the type of the attribute transform that is described by the class.
+  AttributeTransformType transform_type() const { return transform_type_; }
+  void set_transform_type(AttributeTransformType type) {
+    transform_type_ = type;
+  }
+
+  // Returns a parameter value on a given |byte_offset|.
+  template <typename DataTypeT>
+  DataTypeT GetParameterValue(int byte_offset) const {
+    DataTypeT out_data;
+    buffer_.Read(byte_offset, &out_data, sizeof(DataTypeT));
+    return out_data;
+  }
+
+  // Sets a parameter value on a given |byte_offset|.
+  template <typename DataTypeT>
+  void SetParameterValue(int byte_offset, const DataTypeT &in_data) {
+    if (byte_offset + sizeof(DataTypeT) > buffer_.data_size()) {
+      buffer_.Resize(byte_offset + sizeof(DataTypeT));
+    }
+    buffer_.Write(byte_offset, &in_data, sizeof(DataTypeT));
+  }
+
+  // Sets a parameter value at the end of the |buffer_|.
+  template <typename DataTypeT>
+  void AppendParameterValue(const DataTypeT &in_data) {
+    SetParameterValue(static_cast<int>(buffer_.data_size()), in_data);
+  }
+
+ private:
+  AttributeTransformType transform_type_;
+  DataBuffer buffer_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_DATA_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/attribute_transform_type.h

@@ -0,0 +1,30 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_TYPE_H_
+#define DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_TYPE_H_
+
+namespace draco {
+
+// List of all currently supported attribute transforms.
+enum AttributeTransformType {
+  ATTRIBUTE_INVALID_TRANSFORM = -1,
+  ATTRIBUTE_NO_TRANSFORM = 0,
+  ATTRIBUTE_QUANTIZATION_TRANSFORM = 1,
+  ATTRIBUTE_OCTAHEDRON_TRANSFORM = 2,
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_ATTRIBUTE_TRANSFORM_TYPE_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/geometry_attribute.cc

@@ -0,0 +1,102 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/attributes/geometry_attribute.h"
+
+namespace draco {
+
+GeometryAttribute::GeometryAttribute()
+    : buffer_(nullptr),
+      num_components_(1),
+      data_type_(DT_FLOAT32),
+      byte_stride_(0),
+      byte_offset_(0),
+      attribute_type_(INVALID),
+      unique_id_(0) {}
+
+void GeometryAttribute::Init(GeometryAttribute::Type attribute_type,
+                             DataBuffer *buffer, int8_t num_components,
+                             DataType data_type, bool normalized,
+                             int64_t byte_stride, int64_t byte_offset) {
+  buffer_ = buffer;
+  if (buffer) {
+    buffer_descriptor_.buffer_id = buffer->buffer_id();
+    buffer_descriptor_.buffer_update_count = buffer->update_count();
+  }
+  num_components_ = num_components;
+  data_type_ = data_type;
+  normalized_ = normalized;
+  byte_stride_ = byte_stride;
+  byte_offset_ = byte_offset;
+  attribute_type_ = attribute_type;
+}
+
+bool GeometryAttribute::CopyFrom(const GeometryAttribute &src_att) {
+  num_components_ = src_att.num_components_;
+  data_type_ = src_att.data_type_;
+  normalized_ = src_att.normalized_;
+  byte_stride_ = src_att.byte_stride_;
+  byte_offset_ = src_att.byte_offset_;
+  attribute_type_ = src_att.attribute_type_;
+  buffer_descriptor_ = src_att.buffer_descriptor_;
+  unique_id_ = src_att.unique_id_;
+  if (src_att.buffer_ == nullptr) {
+    buffer_ = nullptr;
+  } else {
+    if (buffer_ == nullptr) {
+      return false;
+    }
+    buffer_->Update(src_att.buffer_->data(), src_att.buffer_->data_size());
+  }
+  return true;
+}
+
+bool GeometryAttribute::operator==(const GeometryAttribute &va) const {
+  if (attribute_type_ != va.attribute_type_) {
+    return false;
+  }
+  // It's OK to compare just the buffer descriptors here. We don't need to
+  // compare the buffers themselves.
+  if (buffer_descriptor_.buffer_id != va.buffer_descriptor_.buffer_id) {
+    return false;
+  }
+  if (buffer_descriptor_.buffer_update_count !=
+      va.buffer_descriptor_.buffer_update_count) {
+    return false;
+  }
+  if (num_components_ != va.num_components_) {
+    return false;
+  }
+  if (data_type_ != va.data_type_) {
+    return false;
+  }
+  if (byte_stride_ != va.byte_stride_) {
+    return false;
+  }
+  if (byte_offset_ != va.byte_offset_) {
+    return false;
+  }
+  return true;
+}
+
+void GeometryAttribute::ResetBuffer(DataBuffer *buffer, int64_t byte_stride,
+                                    int64_t byte_offset) {
+  buffer_ = buffer;
+  buffer_descriptor_.buffer_id = buffer->buffer_id();
+  buffer_descriptor_.buffer_update_count = buffer->update_count();
+  byte_stride_ = byte_stride;
+  byte_offset_ = byte_offset;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/attributes/geometry_attribute.h

@@ -0,0 +1,350 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_GEOMETRY_ATTRIBUTE_H_
+#define DRACO_ATTRIBUTES_GEOMETRY_ATTRIBUTE_H_
+
+#include <array>
+#include <limits>
+
+#include "draco/attributes/geometry_indices.h"
+#include "draco/core/data_buffer.h"
+#include "draco/core/hash_utils.h"
+
+namespace draco {
+
+// The class provides access to a specific attribute which is stored in a
+// DataBuffer, such as normals or coordinates. However, the GeometryAttribute
+// class does not own the buffer and the buffer itself may store other data
+// unrelated to this attribute (such as data for other attributes in which case
+// we can have multiple GeometryAttributes accessing one buffer). Typically,
+// all attributes for a point (or corner, face) are stored in one block, which
+// is advantageous in terms of memory access. The length of the entire block is
+// given by the byte_stride, the position where the attribute starts is given by
+// the byte_offset, the actual number of bytes that the attribute occupies is
+// given by the data_type and the number of components.
+class GeometryAttribute {
+ public:
+  // Supported attribute types.
+  enum Type {
+    INVALID = -1,
+    // Named attributes start here. The difference between named and generic
+    // attributes is that for named attributes we know their purpose and we
+    // can apply some special methods when dealing with them (e.g. during
+    // encoding).
+    POSITION = 0,
+    NORMAL,
+    COLOR,
+    TEX_COORD,
+    // A special id used to mark attributes that are not assigned to any known
+    // predefined use case. Such attributes are often used for a shader specific
+    // data.
+    GENERIC,
+    // Total number of different attribute types.
+    // Always keep behind all named attributes.
+    NAMED_ATTRIBUTES_COUNT,
+  };
+
+  GeometryAttribute();
+  // Initializes and enables the attribute.
+  void Init(Type attribute_type, DataBuffer *buffer, int8_t num_components,
+            DataType data_type, bool normalized, int64_t byte_stride,
+            int64_t byte_offset);
+  bool IsValid() const { return buffer_ != nullptr; }
+
+  // Copies data from the source attribute to the this attribute.
+  // This attribute must have a valid buffer allocated otherwise the operation
+  // is going to fail and return false.
+  bool CopyFrom(const GeometryAttribute &src_att);
+
+  // Function for getting a attribute value with a specific format.
+  // Unsafe. Caller must ensure the accessed memory is valid.
+  // T is the attribute data type.
+  // att_components_t is the number of attribute components.
+  template <typename T, int att_components_t>
+  std::array<T, att_components_t> GetValue(
+      AttributeValueIndex att_index) const {
+    // Byte address of the attribute index.
+    const int64_t byte_pos = byte_offset_ + byte_stride_ * att_index.value();
+    std::array<T, att_components_t> out;
+    buffer_->Read(byte_pos, &(out[0]), sizeof(out));
+    return out;
+  }
+
+  // Function for getting a attribute value with a specific format.
+  // T is the attribute data type.
+  // att_components_t is the number of attribute components.
+  template <typename T, int att_components_t>
+  bool GetValue(AttributeValueIndex att_index,
+                std::array<T, att_components_t> *out) const {
+    // Byte address of the attribute index.
+    const int64_t byte_pos = byte_offset_ + byte_stride_ * att_index.value();
+    // Check we are not reading past end of data.
+    if (byte_pos + sizeof(*out) > buffer_->data_size()) {
+      return false;
+    }
+    buffer_->Read(byte_pos, &((*out)[0]), sizeof(*out));
+    return true;
+  }
+
+  // Returns the byte position of the attribute entry in the data buffer.
+  inline int64_t GetBytePos(AttributeValueIndex att_index) const {
+    return byte_offset_ + byte_stride_ * att_index.value();
+  }
+
+  inline const uint8_t *GetAddress(AttributeValueIndex att_index) const {
+    const int64_t byte_pos = GetBytePos(att_index);
+    return buffer_->data() + byte_pos;
+  }
+  inline uint8_t *GetAddress(AttributeValueIndex att_index) {
+    const int64_t byte_pos = GetBytePos(att_index);
+    return buffer_->data() + byte_pos;
+  }
+  inline bool IsAddressValid(const uint8_t *address) const {
+    return ((buffer_->data() + buffer_->data_size()) > address);
+  }
+
+  // Fills out_data with the raw value of the requested attribute entry.
+  // out_data must be at least byte_stride_ long.
+  void GetValue(AttributeValueIndex att_index, void *out_data) const {
+    const int64_t byte_pos = byte_offset_ + byte_stride_ * att_index.value();
+    buffer_->Read(byte_pos, out_data, byte_stride_);
+  }
+
+  // Sets a value of an attribute entry. The input value must be allocated to
+  // cover all components of a single attribute entry.
+  void SetAttributeValue(AttributeValueIndex entry_index, const void *value) {
+    const int64_t byte_pos = entry_index.value() * byte_stride();
+    buffer_->Write(byte_pos, value, byte_stride());
+  }
+
+  // DEPRECATED: Use
+  //   ConvertValue(AttributeValueIndex att_id,
+  //               int out_num_components,
+  //               OutT *out_val);
+  //
+  // Function for conversion of a attribute to a specific output format.
+  // OutT is the desired data type of the attribute.
+  // out_att_components_t is the number of components of the output format.
+  // Returns false when the conversion failed.
+  template <typename OutT, int out_att_components_t>
+  bool ConvertValue(AttributeValueIndex att_id, OutT *out_val) const {
+    return ConvertValue(att_id, out_att_components_t, out_val);
+  }
+
+  // Function for conversion of a attribute to a specific output format.
+  // |out_val| needs to be able to store |out_num_components| values.
+  // OutT is the desired data type of the attribute.
+  // Returns false when the conversion failed.
+  template <typename OutT>
+  bool ConvertValue(AttributeValueIndex att_id, int8_t out_num_components,
+                    OutT *out_val) const {
+    if (out_val == nullptr) {
+      return false;
+    }
+    switch (data_type_) {
+      case DT_INT8:
+        return ConvertTypedValue<int8_t, OutT>(att_id, out_num_components,
+                                               out_val);
+      case DT_UINT8:
+        return ConvertTypedValue<uint8_t, OutT>(att_id, out_num_components,
+                                                out_val);
+      case DT_INT16:
+        return ConvertTypedValue<int16_t, OutT>(att_id, out_num_components,
+                                                out_val);
+      case DT_UINT16:
+        return ConvertTypedValue<uint16_t, OutT>(att_id, out_num_components,
+                                                 out_val);
+      case DT_INT32:
+        return ConvertTypedValue<int32_t, OutT>(att_id, out_num_components,
+                                                out_val);
+      case DT_UINT32:
+        return ConvertTypedValue<uint32_t, OutT>(att_id, out_num_components,
+                                                 out_val);
+      case DT_INT64:
+        return ConvertTypedValue<int64_t, OutT>(att_id, out_num_components,
+                                                out_val);
+      case DT_UINT64:
+        return ConvertTypedValue<uint64_t, OutT>(att_id, out_num_components,
+                                                 out_val);
+      case DT_FLOAT32:
+        return ConvertTypedValue<float, OutT>(att_id, out_num_components,
+                                              out_val);
+      case DT_FLOAT64:
+        return ConvertTypedValue<double, OutT>(att_id, out_num_components,
+                                               out_val);
+      case DT_BOOL:
+        return ConvertTypedValue<bool, OutT>(att_id, out_num_components,
+                                             out_val);
+      default:
+        // Wrong attribute type.
+        return false;
+    }
+  }
+
+  // Function for conversion of a attribute to a specific output format.
+  // The |out_value| must be able to store all components of a single attribute
+  // entry.
+  // OutT is the desired data type of the attribute.
+  // Returns false when the conversion failed.
+  template <typename OutT>
+  bool ConvertValue(AttributeValueIndex att_index, OutT *out_value) const {
+    return ConvertValue<OutT>(att_index, num_components_, out_value);
+  }
+
+  // Utility function. Returns |attribute_type| as std::string.
+  static std::string TypeToString(Type attribute_type) {
+    switch (attribute_type) {
+      case INVALID:
+        return "INVALID";
+      case POSITION:
+        return "POSITION";
+      case NORMAL:
+        return "NORMAL";
+      case COLOR:
+        return "COLOR";
+      case TEX_COORD:
+        return "TEX_COORD";
+      case GENERIC:
+        return "GENERIC";
+      default:
+        return "UNKNOWN";
+    }
+  }
+
+  bool operator==(const GeometryAttribute &va) const;
+
+  // Returns the type of the attribute indicating the nature of the attribute.
+  Type attribute_type() const { return attribute_type_; }
+  void set_attribute_type(Type type) { attribute_type_ = type; }
+  // Returns the data type that is stored in the attribute.
+  DataType data_type() const { return data_type_; }
+  // Returns the number of components that are stored for each entry.
+  // For position attribute this is usually three (x,y,z),
+  // while texture coordinates have two components (u,v).
+  int8_t num_components() const { return num_components_; }
+  // Indicates whether the data type should be normalized before interpretation,
+  // that is, it should be divided by the max value of the data type.
+  bool normalized() const { return normalized_; }
+  // The buffer storing the entire data of the attribute.
+  const DataBuffer *buffer() const { return buffer_; }
+  // Returns the number of bytes between two attribute entries, this is, at
+  // least size of the data types times number of components.
+  int64_t byte_stride() const { return byte_stride_; }
+  // The offset where the attribute starts within the block of size byte_stride.
+  int64_t byte_offset() const { return byte_offset_; }
+  void set_byte_offset(int64_t byte_offset) { byte_offset_ = byte_offset; }
+  DataBufferDescriptor buffer_descriptor() const { return buffer_descriptor_; }
+  uint32_t unique_id() const { return unique_id_; }
+  void set_unique_id(uint32_t id) { unique_id_ = id; }
+
+ protected:
+  // Sets a new internal storage for the attribute.
+  void ResetBuffer(DataBuffer *buffer, int64_t byte_stride,
+                   int64_t byte_offset);
+
+ private:
+  // Function for conversion of an attribute to a specific output format given a
+  // format of the stored attribute.
+  // T is the stored attribute data type.
+  // OutT is the desired data type of the attribute.
+  template <typename T, typename OutT>
+  bool ConvertTypedValue(AttributeValueIndex att_id, int8_t out_num_components,
+                         OutT *out_value) const {
+    const uint8_t *src_address = GetAddress(att_id);
+
+    // Convert all components available in both the original and output formats.
+    for (int i = 0; i < std::min(num_components_, out_num_components); ++i) {
+      if (!IsAddressValid(src_address)) {
+        return false;
+      }
+      const T in_value = *reinterpret_cast<const T *>(src_address);
+
+      // Make sure the in_value fits within the range of values that OutT
+      // is able to represent. Perform the check only for integral types.
+      if (std::is_integral<T>::value && std::is_integral<OutT>::value) {
+        static constexpr OutT kOutMin =
+            std::is_signed<T>::value ? std::numeric_limits<OutT>::lowest() : 0;
+        if (in_value < kOutMin || in_value > std::numeric_limits<OutT>::max()) {
+          return false;
+        }
+      }
+
+      out_value[i] = static_cast<OutT>(in_value);
+      // When converting integer to floating point, normalize the value if
+      // necessary.
+      if (std::is_integral<T>::value && std::is_floating_point<OutT>::value &&
+          normalized_) {
+        out_value[i] /= static_cast<OutT>(std::numeric_limits<T>::max());
+      }
+      // TODO(ostava): Add handling of normalized attributes when converting
+      // between different integer representations. If the attribute is
+      // normalized, integer values should be converted as if they represent 0-1
+      // range. E.g. when we convert uint16 to uint8, the range <0, 2^16 - 1>
+      // should be converted to range <0, 2^8 - 1>.
+      src_address += sizeof(T);
+    }
+    // Fill empty data for unused output components if needed.
+    for (int i = num_components_; i < out_num_components; ++i) {
+      out_value[i] = static_cast<OutT>(0);
+    }
+    return true;
+  }
+
+  DataBuffer *buffer_;
+  // The buffer descriptor is stored at the time the buffer is attached to this
+  // attribute. The purpose is to detect if any changes happened to the buffer
+  // since the time it was attached.
+  DataBufferDescriptor buffer_descriptor_;
+  int8_t num_components_;
+  DataType data_type_;
+  bool normalized_;
+  int64_t byte_stride_;
+  int64_t byte_offset_;
+
+  Type attribute_type_;
+
+  // Unique id of this attribute. No two attributes could have the same unique
+  // id. It is used to identify each attribute, especially when there are
+  // multiple attribute of the same type in a point cloud.
+  uint32_t unique_id_;
+
+  friend struct GeometryAttributeHasher;
+};
+
+// Hashing support
+
+// Function object for using Attribute as a hash key.
+struct GeometryAttributeHasher {
+  size_t operator()(const GeometryAttribute &va) const {
+    size_t hash = HashCombine(va.buffer_descriptor_.buffer_id,
+                              va.buffer_descriptor_.buffer_update_count);
+    hash = HashCombine(va.num_components_, hash);
+    hash = HashCombine(static_cast<int8_t>(va.data_type_), hash);
+    hash = HashCombine(static_cast<int8_t>(va.attribute_type_), hash);
+    hash = HashCombine(va.byte_stride_, hash);
+    return HashCombine(va.byte_offset_, hash);
+  }
+};
+
+// Function object for using GeometryAttribute::Type as a hash key.
+struct GeometryAttributeTypeHasher {
+  size_t operator()(const GeometryAttribute::Type &at) const {
+    return static_cast<size_t>(at);
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_GEOMETRY_ATTRIBUTE_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/geometry_indices.h

@@ -0,0 +1,54 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_GEOMETRY_INDICES_H_
+#define DRACO_ATTRIBUTES_GEOMETRY_INDICES_H_
+
+#include <inttypes.h>
+
+#include <limits>
+
+#include "draco/core/draco_index_type.h"
+
+namespace draco {
+
+// Index of an attribute value entry stored in a GeometryAttribute.
+DEFINE_NEW_DRACO_INDEX_TYPE(uint32_t, AttributeValueIndex)
+// Index of a point in a PointCloud.
+DEFINE_NEW_DRACO_INDEX_TYPE(uint32_t, PointIndex)
+// Vertex index in a Mesh or CornerTable.
+DEFINE_NEW_DRACO_INDEX_TYPE(uint32_t, VertexIndex)
+// Corner index that identifies a corner in a Mesh or CornerTable.
+DEFINE_NEW_DRACO_INDEX_TYPE(uint32_t, CornerIndex)
+// Face index for Mesh and CornerTable.
+DEFINE_NEW_DRACO_INDEX_TYPE(uint32_t, FaceIndex)
+
+// Constants denoting invalid indices.
+static constexpr AttributeValueIndex kInvalidAttributeValueIndex(
+    std::numeric_limits<uint32_t>::max());
+static constexpr PointIndex kInvalidPointIndex(
+    std::numeric_limits<uint32_t>::max());
+static constexpr VertexIndex kInvalidVertexIndex(
+    std::numeric_limits<uint32_t>::max());
+static constexpr CornerIndex kInvalidCornerIndex(
+    std::numeric_limits<uint32_t>::max());
+static constexpr FaceIndex kInvalidFaceIndex(
+    std::numeric_limits<uint32_t>::max());
+
+// TODO(ostava): Add strongly typed indices for attribute id and unique
+// attribute id.
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_GEOMETRY_INDICES_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/point_attribute.cc

@@ -0,0 +1,225 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/attributes/point_attribute.h"
+
+#include <unordered_map>
+
+using std::unordered_map;
+
+// Shortcut for typed conditionals.
+template <bool B, class T, class F>
+using conditional_t = typename std::conditional<B, T, F>::type;
+
+namespace draco {
+
+PointAttribute::PointAttribute()
+    : num_unique_entries_(0), identity_mapping_(false) {}
+
+PointAttribute::PointAttribute(const GeometryAttribute &att)
+    : GeometryAttribute(att),
+      num_unique_entries_(0),
+      identity_mapping_(false) {}
+
+void PointAttribute::Init(Type attribute_type, int8_t num_components,
+                          DataType data_type, bool normalized,
+                          size_t num_attribute_values) {
+  attribute_buffer_ = std::unique_ptr<DataBuffer>(new DataBuffer());
+  GeometryAttribute::Init(attribute_type, attribute_buffer_.get(),
+                          num_components, data_type, normalized,
+                          DataTypeLength(data_type) * num_components, 0);
+  Reset(num_attribute_values);
+  SetIdentityMapping();
+}
+
+void PointAttribute::CopyFrom(const PointAttribute &src_att) {
+  if (buffer() == nullptr) {
+    // If the destination attribute doesn't have a valid buffer, create it.
+    attribute_buffer_ = std::unique_ptr<DataBuffer>(new DataBuffer());
+    ResetBuffer(attribute_buffer_.get(), 0, 0);
+  }
+  if (!GeometryAttribute::CopyFrom(src_att)) {
+    return;
+  }
+  identity_mapping_ = src_att.identity_mapping_;
+  num_unique_entries_ = src_att.num_unique_entries_;
+  indices_map_ = src_att.indices_map_;
+  if (src_att.attribute_transform_data_) {
+    attribute_transform_data_ = std::unique_ptr<AttributeTransformData>(
+        new AttributeTransformData(*src_att.attribute_transform_data_));
+  } else {
+    attribute_transform_data_ = nullptr;
+  }
+}
+
+bool PointAttribute::Reset(size_t num_attribute_values) {
+  if (attribute_buffer_ == nullptr) {
+    attribute_buffer_ = std::unique_ptr<DataBuffer>(new DataBuffer());
+  }
+  const int64_t entry_size = DataTypeLength(data_type()) * num_components();
+  if (!attribute_buffer_->Update(nullptr, num_attribute_values * entry_size)) {
+    return false;
+  }
+  // Assign the new buffer to the parent attribute.
+  ResetBuffer(attribute_buffer_.get(), entry_size, 0);
+  num_unique_entries_ = static_cast<uint32_t>(num_attribute_values);
+  return true;
+}
+
+void PointAttribute::Resize(size_t new_num_unique_entries) {
+  num_unique_entries_ = static_cast<uint32_t>(new_num_unique_entries);
+  attribute_buffer_->Resize(new_num_unique_entries * byte_stride());
+}
+
+#ifdef DRACO_ATTRIBUTE_VALUES_DEDUPLICATION_SUPPORTED
+AttributeValueIndex::ValueType PointAttribute::DeduplicateValues(
+    const GeometryAttribute &in_att) {
+  return DeduplicateValues(in_att, AttributeValueIndex(0));
+}
+
+AttributeValueIndex::ValueType PointAttribute::DeduplicateValues(
+    const GeometryAttribute &in_att, AttributeValueIndex in_att_offset) {
+  AttributeValueIndex::ValueType unique_vals = 0;
+  switch (in_att.data_type()) {
+    // Currently we support only float, uint8, and uint16 arguments.
+    case DT_FLOAT32:
+      unique_vals = DeduplicateTypedValues<float>(in_att, in_att_offset);
+      break;
+    case DT_INT8:
+      unique_vals = DeduplicateTypedValues<int8_t>(in_att, in_att_offset);
+      break;
+    case DT_UINT8:
+    case DT_BOOL:
+      unique_vals = DeduplicateTypedValues<uint8_t>(in_att, in_att_offset);
+      break;
+    case DT_UINT16:
+      unique_vals = DeduplicateTypedValues<uint16_t>(in_att, in_att_offset);
+      break;
+    case DT_INT16:
+      unique_vals = DeduplicateTypedValues<int16_t>(in_att, in_att_offset);
+      break;
+    case DT_UINT32:
+      unique_vals = DeduplicateTypedValues<uint32_t>(in_att, in_att_offset);
+      break;
+    case DT_INT32:
+      unique_vals = DeduplicateTypedValues<int32_t>(in_att, in_att_offset);
+      break;
+    default:
+      return -1;  // Unsupported data type.
+  }
+  if (unique_vals == 0) {
+    return -1;  // Unexpected error.
+  }
+  return unique_vals;
+}
+
+// Helper function for calling UnifyDuplicateAttributes<T,num_components_t>
+// with the correct template arguments.
+// Returns the number of unique attribute values.
+template <typename T>
+AttributeValueIndex::ValueType PointAttribute::DeduplicateTypedValues(
+    const GeometryAttribute &in_att, AttributeValueIndex in_att_offset) {
+  // Select the correct method to call based on the number of attribute
+  // components.
+  switch (in_att.num_components()) {
+    case 1:
+      return DeduplicateFormattedValues<T, 1>(in_att, in_att_offset);
+    case 2:
+      return DeduplicateFormattedValues<T, 2>(in_att, in_att_offset);
+    case 3:
+      return DeduplicateFormattedValues<T, 3>(in_att, in_att_offset);
+    case 4:
+      return DeduplicateFormattedValues<T, 4>(in_att, in_att_offset);
+    default:
+      return 0;
+  }
+}
+
+template <typename T, int num_components_t>
+AttributeValueIndex::ValueType PointAttribute::DeduplicateFormattedValues(
+    const GeometryAttribute &in_att, AttributeValueIndex in_att_offset) {
+  // We want to detect duplicates using a hash map but we cannot hash floating
+  // point numbers directly so bit-copy floats to the same sized integers and
+  // hash them.
+
+  // First we need to determine which int type to use (1, 2, 4 or 8 bytes).
+  // Note, this is done at compile time using std::conditional struct.
+  // Conditional is in form <bool-expression, true, false>. If bool-expression
+  // is true the "true" branch is used and vice versa. All at compile time.
+  typedef conditional_t<sizeof(T) == 1, uint8_t,
+                        conditional_t<sizeof(T) == 2, uint16_t,
+                                      conditional_t<sizeof(T) == 4, uint32_t,
+                                                    /*else*/ uint64_t>>>
+      HashType;
+
+  AttributeValueIndex unique_vals(0);
+  typedef std::array<T, num_components_t> AttributeValue;
+  typedef std::array<HashType, num_components_t> AttributeHashableValue;
+  // Hash map storing index of the first attribute with a given value.
+  unordered_map<AttributeHashableValue, AttributeValueIndex,
+                HashArray<AttributeHashableValue>>
+      value_to_index_map;
+  AttributeValue att_value;
+  AttributeHashableValue hashable_value;
+  IndexTypeVector<AttributeValueIndex, AttributeValueIndex> value_map(
+      num_unique_entries_);
+  for (AttributeValueIndex i(0); i < num_unique_entries_; ++i) {
+    const AttributeValueIndex att_pos = i + in_att_offset;
+    att_value = in_att.GetValue<T, num_components_t>(att_pos);
+    // Convert the value to hashable type. Bit-copy real attributes to integers.
+    memcpy(&(hashable_value[0]), &(att_value[0]), sizeof(att_value));
+
+    // Check if the given attribute value has been used before already.
+    auto it = value_to_index_map.find(hashable_value);
+    if (it != value_to_index_map.end()) {
+      // Duplicated value found. Update index mapping.
+      value_map[i] = it->second;
+    } else {
+      // New unique value.
+      // Update the hash map with a new entry pointing to the latest unique
+      // vertex index.
+      value_to_index_map.insert(
+          std::pair<AttributeHashableValue, AttributeValueIndex>(hashable_value,
+                                                                 unique_vals));
+      // Add the unique value to the mesh builder.
+      SetAttributeValue(unique_vals, &att_value);
+      // Update index mapping.
+      value_map[i] = unique_vals;
+
+      ++unique_vals;
+    }
+  }
+  if (unique_vals == num_unique_entries_) {
+    return unique_vals.value();  // Nothing has changed.
+  }
+  if (is_mapping_identity()) {
+    // Change identity mapping to the explicit one.
+    // The number of points is equal to the number of old unique values.
+    SetExplicitMapping(num_unique_entries_);
+    // Update the explicit map.
+    for (uint32_t i = 0; i < num_unique_entries_; ++i) {
+      SetPointMapEntry(PointIndex(i), value_map[AttributeValueIndex(i)]);
+    }
+  } else {
+    // Update point to value map using the mapping between old and new values.
+    for (PointIndex i(0); i < static_cast<uint32_t>(indices_map_.size()); ++i) {
+      SetPointMapEntry(i, value_map[indices_map_[i]]);
+    }
+  }
+  num_unique_entries_ = unique_vals.value();
+  return num_unique_entries_;
+}
+#endif
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/attributes/point_attribute.h

@@ -0,0 +1,190 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_ATTRIBUTES_POINT_ATTRIBUTE_H_
+#define DRACO_ATTRIBUTES_POINT_ATTRIBUTE_H_
+
+#include <memory>
+
+#include "draco/attributes/attribute_transform_data.h"
+#include "draco/attributes/geometry_attribute.h"
+#include "draco/core/draco_index_type_vector.h"
+#include "draco/core/hash_utils.h"
+#include "draco/core/macros.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Class for storing point specific data about each attribute. In general,
+// multiple points stored in a point cloud can share the same attribute value
+// and this class provides the necessary mapping between point ids and attribute
+// value ids.
+class PointAttribute : public GeometryAttribute {
+ public:
+  PointAttribute();
+  explicit PointAttribute(const GeometryAttribute &att);
+
+  // Make sure the move constructor is defined (needed for better performance
+  // when new attributes are added to PointCloud).
+  PointAttribute(PointAttribute &&attribute) = default;
+  PointAttribute &operator=(PointAttribute &&attribute) = default;
+
+  // Initializes a point attribute. By default the attribute will be set to
+  // identity mapping between point indices and attribute values. To set custom
+  // mapping use SetExplicitMapping() function.
+  void Init(Type attribute_type, int8_t num_components, DataType data_type,
+            bool normalized, size_t num_attribute_values);
+
+  // Copies attribute data from the provided |src_att| attribute.
+  void CopyFrom(const PointAttribute &src_att);
+
+  // Prepares the attribute storage for the specified number of entries.
+  bool Reset(size_t num_attribute_values);
+
+  size_t size() const { return num_unique_entries_; }
+  AttributeValueIndex mapped_index(PointIndex point_index) const {
+    if (identity_mapping_) {
+      return AttributeValueIndex(point_index.value());
+    }
+    return indices_map_[point_index];
+  }
+  DataBuffer *buffer() const { return attribute_buffer_.get(); }
+  bool is_mapping_identity() const { return identity_mapping_; }
+  size_t indices_map_size() const {
+    if (is_mapping_identity()) {
+      return 0;
+    }
+    return indices_map_.size();
+  }
+
+  const uint8_t *GetAddressOfMappedIndex(PointIndex point_index) const {
+    return GetAddress(mapped_index(point_index));
+  }
+
+  // Sets the new number of unique attribute entries for the attribute. The
+  // function resizes the attribute storage to hold |num_attribute_values|
+  // entries.
+  // All previous entries with AttributeValueIndex < |num_attribute_values|
+  // are preserved. Caller needs to ensure that the PointAttribute is still
+  // valid after the resizing operation (that is, each point is mapped to a
+  // valid attribute value).
+  void Resize(size_t new_num_unique_entries);
+
+  // Functions for setting the type of mapping between point indices and
+  // attribute entry ids.
+  // This function sets the mapping to implicit, where point indices are equal
+  // to attribute entry indices.
+  void SetIdentityMapping() {
+    identity_mapping_ = true;
+    indices_map_.clear();
+  }
+  // This function sets the mapping to be explicitly using the indices_map_
+  // array that needs to be initialized by the caller.
+  void SetExplicitMapping(size_t num_points) {
+    identity_mapping_ = false;
+    indices_map_.resize(num_points, kInvalidAttributeValueIndex);
+  }
+
+  // Set an explicit map entry for a specific point index.
+  void SetPointMapEntry(PointIndex point_index,
+                        AttributeValueIndex entry_index) {
+    DRACO_DCHECK(!identity_mapping_);
+    indices_map_[point_index] = entry_index;
+  }
+
+  // Same as GeometryAttribute::GetValue(), but using point id as the input.
+  // Mapping to attribute value index is performed automatically.
+  void GetMappedValue(PointIndex point_index, void *out_data) const {
+    return GetValue(mapped_index(point_index), out_data);
+  }
+
+#ifdef DRACO_ATTRIBUTE_VALUES_DEDUPLICATION_SUPPORTED
+  // Deduplicate |in_att| values into |this| attribute. |in_att| can be equal
+  // to |this|.
+  // Returns -1 if the deduplication failed.
+  AttributeValueIndex::ValueType DeduplicateValues(
+      const GeometryAttribute &in_att);
+
+  // Same as above but the values read from |in_att| are sampled with the
+  // provided offset |in_att_offset|.
+  AttributeValueIndex::ValueType DeduplicateValues(
+      const GeometryAttribute &in_att, AttributeValueIndex in_att_offset);
+#endif
+
+  // Set attribute transform data for the attribute. The data is used to store
+  // the type and parameters of the transform that is applied on the attribute
+  // data (optional).
+  void SetAttributeTransformData(
+      std::unique_ptr<AttributeTransformData> transform_data) {
+    attribute_transform_data_ = std::move(transform_data);
+  }
+  const AttributeTransformData *GetAttributeTransformData() const {
+    return attribute_transform_data_.get();
+  }
+
+ private:
+#ifdef DRACO_ATTRIBUTE_VALUES_DEDUPLICATION_SUPPORTED
+  template <typename T>
+  AttributeValueIndex::ValueType DeduplicateTypedValues(
+      const GeometryAttribute &in_att, AttributeValueIndex in_att_offset);
+  template <typename T, int COMPONENTS_COUNT>
+  AttributeValueIndex::ValueType DeduplicateFormattedValues(
+      const GeometryAttribute &in_att, AttributeValueIndex in_att_offset);
+#endif
+
+  // Data storage for attribute values. GeometryAttribute itself doesn't own its
+  // buffer so we need to allocate it here.
+  std::unique_ptr<DataBuffer> attribute_buffer_;
+
+  // Mapping between point ids and attribute value ids.
+  IndexTypeVector<PointIndex, AttributeValueIndex> indices_map_;
+  AttributeValueIndex::ValueType num_unique_entries_;
+  // Flag when the mapping between point ids and attribute values is identity.
+  bool identity_mapping_;
+
+  // If an attribute contains transformed data (e.g. quantized), we can specify
+  // the attribute transform here and use it to transform the attribute back to
+  // its original format.
+  std::unique_ptr<AttributeTransformData> attribute_transform_data_;
+
+  friend struct PointAttributeHasher;
+};
+
+// Hash functor for the PointAttribute class.
+struct PointAttributeHasher {
+  size_t operator()(const PointAttribute &attribute) const {
+    GeometryAttributeHasher base_hasher;
+    size_t hash = base_hasher(attribute);
+    hash = HashCombine(attribute.identity_mapping_, hash);
+    hash = HashCombine(attribute.num_unique_entries_, hash);
+    hash = HashCombine(attribute.indices_map_.size(), hash);
+    if (!attribute.indices_map_.empty()) {
+      const uint64_t indices_hash = FingerprintString(
+          reinterpret_cast<const char *>(attribute.indices_map_.data()),
+          attribute.indices_map_.size());
+      hash = HashCombine(indices_hash, hash);
+    }
+    if (attribute.attribute_buffer_ != nullptr) {
+      const uint64_t buffer_hash = FingerprintString(
+          reinterpret_cast<const char *>(attribute.attribute_buffer_->data()),
+          attribute.attribute_buffer_->data_size());
+      hash = HashCombine(buffer_hash, hash);
+    }
+    return hash;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_ATTRIBUTES_POINT_ATTRIBUTE_H_

Engine/lib/assimp/contrib/draco/src/draco/attributes/point_attribute_test.cc

@@ -0,0 +1,128 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/attributes/point_attribute.h"
+
+#include "draco/core/draco_test_base.h"
+
+namespace {
+
+class PointAttributeTest : public ::testing::Test {
+ protected:
+  PointAttributeTest() {}
+};
+
+TEST_F(PointAttributeTest, TestCopy) {
+  // This test verifies that PointAttribute can copy data from another point
+  // attribute.
+  draco::PointAttribute pa;
+  pa.Init(draco::GeometryAttribute::POSITION, 1, draco::DT_INT32, false, 10);
+
+  for (int32_t i = 0; i < 10; ++i) {
+    pa.SetAttributeValue(draco::AttributeValueIndex(i), &i);
+  }
+
+  pa.set_unique_id(12);
+
+  draco::PointAttribute other_pa;
+  other_pa.CopyFrom(pa);
+
+  draco::PointAttributeHasher hasher;
+  ASSERT_EQ(hasher(pa), hasher(other_pa));
+  ASSERT_EQ(pa.unique_id(), other_pa.unique_id());
+
+  // The hash function does not actually compute the hash from attribute values,
+  // so ensure the data got copied correctly as well.
+  for (int32_t i = 0; i < 10; ++i) {
+    int32_t data;
+    other_pa.GetValue(draco::AttributeValueIndex(i), &data);
+    ASSERT_EQ(data, i);
+  }
+}
+
+TEST_F(PointAttributeTest, TestGetValueFloat) {
+  draco::PointAttribute pa;
+  pa.Init(draco::GeometryAttribute::POSITION, 3, draco::DT_FLOAT32, false, 5);
+  float points[3];
+  for (int32_t i = 0; i < 5; ++i) {
+    points[0] = i * 3.0;
+    points[1] = (i * 3.0) + 1.0;
+    points[2] = (i * 3.0) + 2.0;
+    pa.SetAttributeValue(draco::AttributeValueIndex(i), &points);
+  }
+
+  for (int32_t i = 0; i < 5; ++i) {
+    pa.GetValue(draco::AttributeValueIndex(i), &points);
+    ASSERT_FLOAT_EQ(points[0], i * 3.0);
+    ASSERT_FLOAT_EQ(points[1], (i * 3.0) + 1.0);
+    ASSERT_FLOAT_EQ(points[2], (i * 3.0) + 2.0);
+  }
+}
+
+TEST_F(PointAttributeTest, TestGetArray) {
+  draco::PointAttribute pa;
+  pa.Init(draco::GeometryAttribute::POSITION, 3, draco::DT_FLOAT32, false, 5);
+  float points[3];
+  for (int32_t i = 0; i < 5; ++i) {
+    points[0] = i * 3.0;
+    points[1] = (i * 3.0) + 1.0;
+    points[2] = (i * 3.0) + 2.0;
+    pa.SetAttributeValue(draco::AttributeValueIndex(i), &points);
+  }
+
+  for (int32_t i = 0; i < 5; ++i) {
+    std::array<float, 3> att_value;
+    att_value = pa.GetValue<float, 3>(draco::AttributeValueIndex(i));
+    ASSERT_FLOAT_EQ(att_value[0], i * 3.0);
+    ASSERT_FLOAT_EQ(att_value[1], (i * 3.0) + 1.0);
+    ASSERT_FLOAT_EQ(att_value[2], (i * 3.0) + 2.0);
+  }
+  for (int32_t i = 0; i < 5; ++i) {
+    std::array<float, 3> att_value;
+    EXPECT_TRUE(
+        (pa.GetValue<float, 3>(draco::AttributeValueIndex(i), &att_value)));
+    ASSERT_FLOAT_EQ(att_value[0], i * 3.0);
+    ASSERT_FLOAT_EQ(att_value[1], (i * 3.0) + 1.0);
+    ASSERT_FLOAT_EQ(att_value[2], (i * 3.0) + 2.0);
+  }
+}
+
+TEST_F(PointAttributeTest, TestArrayReadError) {
+  draco::PointAttribute pa;
+  pa.Init(draco::GeometryAttribute::POSITION, 3, draco::DT_FLOAT32, false, 5);
+  float points[3];
+  for (int32_t i = 0; i < 5; ++i) {
+    points[0] = i * 3.0;
+    points[1] = (i * 3.0) + 1.0;
+    points[2] = (i * 3.0) + 2.0;
+    pa.SetAttributeValue(draco::AttributeValueIndex(i), &points);
+  }
+
+  std::array<float, 3> att_value;
+  EXPECT_FALSE(
+      (pa.GetValue<float, 3>(draco::AttributeValueIndex(5), &att_value)));
+}
+
+TEST_F(PointAttributeTest, TestResize) {
+  draco::PointAttribute pa;
+  pa.Init(draco::GeometryAttribute::POSITION, 3, draco::DT_FLOAT32, false, 5);
+  ASSERT_EQ(pa.size(), 5);
+  ASSERT_EQ(pa.buffer()->data_size(), 4 * 3 * 5);
+
+  pa.Resize(10);
+  ASSERT_EQ(pa.size(), 10);
+  ASSERT_EQ(pa.buffer()->data_size(), 4 * 3 * 10);
+}
+
+}  // namespace

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/attributes_decoder.cc

@@ -0,0 +1,127 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/attributes_decoder.h"
+
+#include "draco/core/varint_decoding.h"
+
+namespace draco {
+
+AttributesDecoder::AttributesDecoder()
+    : point_cloud_decoder_(nullptr), point_cloud_(nullptr) {}
+
+bool AttributesDecoder::Init(PointCloudDecoder *decoder, PointCloud *pc) {
+  point_cloud_decoder_ = decoder;
+  point_cloud_ = pc;
+  return true;
+}
+
+bool AttributesDecoder::DecodeAttributesDecoderData(DecoderBuffer *in_buffer) {
+  // Decode and create attributes.
+  uint32_t num_attributes;
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (point_cloud_decoder_->bitstream_version() <
+      DRACO_BITSTREAM_VERSION(2, 0)) {
+    if (!in_buffer->Decode(&num_attributes)) {
+      return false;
+    }
+  } else
+#endif
+  {
+    if (!DecodeVarint(&num_attributes, in_buffer)) {
+      return false;
+    }
+  }
+
+  // Check that decoded number of attributes is valid.
+  if (num_attributes == 0) {
+    return false;
+  }
+  if (num_attributes > 5 * in_buffer->remaining_size()) {
+    // The decoded number of attributes is unreasonably high, because at least
+    // five bytes of attribute descriptor data per attribute are expected.
+    return false;
+  }
+
+  // Decode attribute descriptor data.
+  point_attribute_ids_.resize(num_attributes);
+  PointCloud *pc = point_cloud_;
+  for (uint32_t i = 0; i < num_attributes; ++i) {
+    // Decode attribute descriptor data.
+    uint8_t att_type, data_type, num_components, normalized;
+    if (!in_buffer->Decode(&att_type)) {
+      return false;
+    }
+    if (!in_buffer->Decode(&data_type)) {
+      return false;
+    }
+    if (!in_buffer->Decode(&num_components)) {
+      return false;
+    }
+    if (!in_buffer->Decode(&normalized)) {
+      return false;
+    }
+    if (att_type >= GeometryAttribute::NAMED_ATTRIBUTES_COUNT) {
+      return false;
+    }
+    if (data_type == DT_INVALID || data_type >= DT_TYPES_COUNT) {
+      return false;
+    }
+
+    // Check decoded attribute descriptor data.
+    if (num_components == 0) {
+      return false;
+    }
+
+    // Add the attribute to the point cloud.
+    const DataType draco_dt = static_cast<DataType>(data_type);
+    GeometryAttribute ga;
+    ga.Init(static_cast<GeometryAttribute::Type>(att_type), nullptr,
+            num_components, draco_dt, normalized > 0,
+            DataTypeLength(draco_dt) * num_components, 0);
+    uint32_t unique_id;
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+    if (point_cloud_decoder_->bitstream_version() <
+        DRACO_BITSTREAM_VERSION(1, 3)) {
+      uint16_t custom_id;
+      if (!in_buffer->Decode(&custom_id)) {
+        return false;
+      }
+      // TODO(draco-eng): Add "custom_id" to attribute metadata.
+      unique_id = static_cast<uint32_t>(custom_id);
+      ga.set_unique_id(unique_id);
+    } else
+#endif
+    {
+      if (!DecodeVarint(&unique_id, in_buffer)) {
+        return false;
+      }
+      ga.set_unique_id(unique_id);
+    }
+    const int att_id = pc->AddAttribute(
+        std::unique_ptr<PointAttribute>(new PointAttribute(ga)));
+    pc->attribute(att_id)->set_unique_id(unique_id);
+    point_attribute_ids_[i] = att_id;
+
+    // Update the inverse map.
+    if (att_id >=
+        static_cast<int32_t>(point_attribute_to_local_id_map_.size())) {
+      point_attribute_to_local_id_map_.resize(att_id + 1, -1);
+    }
+    point_attribute_to_local_id_map_[att_id] = i;
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/attributes_decoder.h

@@ -0,0 +1,97 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_H_
+
+#include <vector>
+
+#include "draco/compression/attributes/attributes_decoder_interface.h"
+#include "draco/compression/point_cloud/point_cloud_decoder.h"
+#include "draco/core/decoder_buffer.h"
+#include "draco/draco_features.h"
+#include "draco/point_cloud/point_cloud.h"
+
+namespace draco {
+
+// Base class for decoding one or more attributes that were encoded with a
+// matching AttributesEncoder. It is a basic implementation of
+// AttributesDecoderInterface that provides functionality that is shared between
+// all AttributesDecoders.
+class AttributesDecoder : public AttributesDecoderInterface {
+ public:
+  AttributesDecoder();
+  virtual ~AttributesDecoder() = default;
+
+  // Called after all attribute decoders are created. It can be used to perform
+  // any custom initialization.
+  bool Init(PointCloudDecoder *decoder, PointCloud *pc) override;
+
+  // Decodes any attribute decoder specific data from the |in_buffer|.
+  bool DecodeAttributesDecoderData(DecoderBuffer *in_buffer) override;
+
+  int32_t GetAttributeId(int i) const override {
+    return point_attribute_ids_[i];
+  }
+  int32_t GetNumAttributes() const override {
+    return static_cast<int32_t>(point_attribute_ids_.size());
+  }
+  PointCloudDecoder *GetDecoder() const override {
+    return point_cloud_decoder_;
+  }
+
+  // Decodes attribute data from the source buffer.
+  bool DecodeAttributes(DecoderBuffer *in_buffer) override {
+    if (!DecodePortableAttributes(in_buffer)) {
+      return false;
+    }
+    if (!DecodeDataNeededByPortableTransforms(in_buffer)) {
+      return false;
+    }
+    if (!TransformAttributesToOriginalFormat()) {
+      return false;
+    }
+    return true;
+  }
+
+ protected:
+  int32_t GetLocalIdForPointAttribute(int32_t point_attribute_id) const {
+    const int id_map_size =
+        static_cast<int>(point_attribute_to_local_id_map_.size());
+    if (point_attribute_id >= id_map_size) {
+      return -1;
+    }
+    return point_attribute_to_local_id_map_[point_attribute_id];
+  }
+  virtual bool DecodePortableAttributes(DecoderBuffer *in_buffer) = 0;
+  virtual bool DecodeDataNeededByPortableTransforms(DecoderBuffer *in_buffer) {
+    return true;
+  }
+  virtual bool TransformAttributesToOriginalFormat() { return true; }
+
+ private:
+  // List of attribute ids that need to be decoded with this decoder.
+  std::vector<int32_t> point_attribute_ids_;
+
+  // Map between point attribute id and the local id (i.e., the inverse of the
+  // |point_attribute_ids_|.
+  std::vector<int32_t> point_attribute_to_local_id_map_;
+
+  PointCloudDecoder *point_cloud_decoder_;
+  PointCloud *point_cloud_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/attributes_decoder_interface.h

@@ -0,0 +1,62 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_INTERFACE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_INTERFACE_H_
+
+#include <vector>
+
+#include "draco/core/decoder_buffer.h"
+#include "draco/point_cloud/point_cloud.h"
+
+namespace draco {
+
+class PointCloudDecoder;
+
+// Interface class for decoding one or more attributes that were encoded with a
+// matching AttributesEncoder. It provides only the basic interface
+// that is used by the PointCloudDecoder. The actual decoding must be
+// implemented in derived classes using the DecodeAttributes() method.
+class AttributesDecoderInterface {
+ public:
+  AttributesDecoderInterface() = default;
+  virtual ~AttributesDecoderInterface() = default;
+
+  // Called after all attribute decoders are created. It can be used to perform
+  // any custom initialization.
+  virtual bool Init(PointCloudDecoder *decoder, PointCloud *pc) = 0;
+
+  // Decodes any attribute decoder specific data from the |in_buffer|.
+  virtual bool DecodeAttributesDecoderData(DecoderBuffer *in_buffer) = 0;
+
+  // Decode attribute data from the source buffer. Needs to be implemented by
+  // the derived classes.
+  virtual bool DecodeAttributes(DecoderBuffer *in_buffer) = 0;
+
+  virtual int32_t GetAttributeId(int i) const = 0;
+  virtual int32_t GetNumAttributes() const = 0;
+  virtual PointCloudDecoder *GetDecoder() const = 0;
+
+  // Returns an attribute containing data processed by the attribute transform.
+  // (see TransformToPortableFormat() method). This data is guaranteed to be
+  // same for encoder and decoder and it can be used by predictors.
+  virtual const PointAttribute *GetPortableAttribute(
+      int32_t /* point_attribute_id */) {
+    return nullptr;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_DECODER_INTERFACE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/attributes_encoder.cc

@@ -0,0 +1,49 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/attributes_encoder.h"
+
+#include "draco/core/varint_encoding.h"
+
+namespace draco {
+
+AttributesEncoder::AttributesEncoder()
+    : point_cloud_encoder_(nullptr), point_cloud_(nullptr) {}
+
+AttributesEncoder::AttributesEncoder(int att_id) : AttributesEncoder() {
+  AddAttributeId(att_id);
+}
+
+bool AttributesEncoder::Init(PointCloudEncoder *encoder, const PointCloud *pc) {
+  point_cloud_encoder_ = encoder;
+  point_cloud_ = pc;
+  return true;
+}
+
+bool AttributesEncoder::EncodeAttributesEncoderData(EncoderBuffer *out_buffer) {
+  // Encode data about all attributes.
+  EncodeVarint(num_attributes(), out_buffer);
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    const int32_t att_id = point_attribute_ids_[i];
+    const PointAttribute *const pa = point_cloud_->attribute(att_id);
+    out_buffer->Encode(static_cast<uint8_t>(pa->attribute_type()));
+    out_buffer->Encode(static_cast<uint8_t>(pa->data_type()));
+    out_buffer->Encode(static_cast<uint8_t>(pa->num_components()));
+    out_buffer->Encode(static_cast<uint8_t>(pa->normalized()));
+    EncodeVarint(pa->unique_id(), out_buffer);
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/attributes_encoder.h

@@ -0,0 +1,154 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_ENCODER_H_
+
+#include "draco/attributes/point_attribute.h"
+#include "draco/core/encoder_buffer.h"
+#include "draco/point_cloud/point_cloud.h"
+
+namespace draco {
+
+class PointCloudEncoder;
+
+// Base class for encoding one or more attributes of a PointCloud (or other
+// geometry). This base class provides only the basic interface that is used
+// by the PointCloudEncoder.
+class AttributesEncoder {
+ public:
+  AttributesEncoder();
+  // Constructs an attribute encoder associated with a given point attribute.
+  explicit AttributesEncoder(int point_attrib_id);
+  virtual ~AttributesEncoder() = default;
+
+  // Called after all attribute encoders are created. It can be used to perform
+  // any custom initialization, including setting up attribute dependencies.
+  // Note: no data should be encoded in this function, because the decoder may
+  // process encoders in a different order from the decoder.
+  virtual bool Init(PointCloudEncoder *encoder, const PointCloud *pc);
+
+  // Encodes data needed by the target attribute decoder.
+  virtual bool EncodeAttributesEncoderData(EncoderBuffer *out_buffer);
+
+  // Returns a unique identifier of the given encoder type, that is used during
+  // decoding to construct the corresponding attribute decoder.
+  virtual uint8_t GetUniqueId() const = 0;
+
+  // Encode attribute data to the target buffer.
+  virtual bool EncodeAttributes(EncoderBuffer *out_buffer) {
+    if (!TransformAttributesToPortableFormat()) {
+      return false;
+    }
+    if (!EncodePortableAttributes(out_buffer)) {
+      return false;
+    }
+    // Encode data needed by portable transforms after the attribute is encoded.
+    // This corresponds to the order in which the data is going to be decoded by
+    // the decoder.
+    if (!EncodeDataNeededByPortableTransforms(out_buffer)) {
+      return false;
+    }
+    return true;
+  }
+
+  // Returns the number of attributes that need to be encoded before the
+  // specified attribute is encoded.
+  // Note that the attribute is specified by its point attribute id.
+  virtual int NumParentAttributes(int32_t /* point_attribute_id */) const {
+    return 0;
+  }
+
+  virtual int GetParentAttributeId(int32_t /* point_attribute_id */,
+                                   int32_t /* parent_i */) const {
+    return -1;
+  }
+
+  // Marks a given attribute as a parent of another attribute.
+  virtual bool MarkParentAttribute(int32_t /* point_attribute_id */) {
+    return false;
+  }
+
+  // Returns an attribute containing data processed by the attribute transform.
+  // (see TransformToPortableFormat() method). This data is guaranteed to be
+  // encoded losslessly and it can be safely used for predictors.
+  virtual const PointAttribute *GetPortableAttribute(
+      int32_t /* point_attribute_id */) {
+    return nullptr;
+  }
+
+  void AddAttributeId(int32_t id) {
+    point_attribute_ids_.push_back(id);
+    if (id >= static_cast<int32_t>(point_attribute_to_local_id_map_.size())) {
+      point_attribute_to_local_id_map_.resize(id + 1, -1);
+    }
+    point_attribute_to_local_id_map_[id] =
+        static_cast<int32_t>(point_attribute_ids_.size()) - 1;
+  }
+
+  // Sets new attribute point ids (replacing the existing ones).
+  void SetAttributeIds(const std::vector<int32_t> &point_attribute_ids) {
+    point_attribute_ids_.clear();
+    point_attribute_to_local_id_map_.clear();
+    for (int32_t att_id : point_attribute_ids) {
+      AddAttributeId(att_id);
+    }
+  }
+
+  int32_t GetAttributeId(int i) const { return point_attribute_ids_[i]; }
+  uint32_t num_attributes() const {
+    return static_cast<uint32_t>(point_attribute_ids_.size());
+  }
+  PointCloudEncoder *encoder() const { return point_cloud_encoder_; }
+
+ protected:
+  // Transforms the input attribute data into a form that should be losslessly
+  // encoded (transform itself can be lossy).
+  virtual bool TransformAttributesToPortableFormat() { return true; }
+
+  // Losslessly encodes data of all portable attributes.
+  // Precondition: All attributes must have been transformed into portable
+  // format at this point (see TransformAttributesToPortableFormat() method).
+  virtual bool EncodePortableAttributes(EncoderBuffer *out_buffer) = 0;
+
+  // Encodes any data needed to revert the transform to portable format for each
+  // attribute (e.g. data needed for dequantization of quantized values).
+  virtual bool EncodeDataNeededByPortableTransforms(EncoderBuffer *out_buffer) {
+    return true;
+  }
+
+  int32_t GetLocalIdForPointAttribute(int32_t point_attribute_id) const {
+    const int id_map_size =
+        static_cast<int>(point_attribute_to_local_id_map_.size());
+    if (point_attribute_id >= id_map_size) {
+      return -1;
+    }
+    return point_attribute_to_local_id_map_[point_attribute_id];
+  }
+
+ private:
+  // List of attribute ids that need to be encoded with this encoder.
+  std::vector<int32_t> point_attribute_ids_;
+
+  // Map between point attribute id and the local id (i.e., the inverse of the
+  // |point_attribute_ids_|.
+  std::vector<int32_t> point_attribute_to_local_id_map_;
+
+  PointCloudEncoder *point_cloud_encoder_;
+  const PointCloud *point_cloud_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_ATTRIBUTES_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/kd_tree_attributes_decoder.cc

@@ -0,0 +1,556 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/kd_tree_attributes_decoder.h"
+
+#include "draco/compression/attributes/kd_tree_attributes_shared.h"
+#include "draco/compression/point_cloud/algorithms/dynamic_integer_points_kd_tree_decoder.h"
+#include "draco/compression/point_cloud/algorithms/float_points_tree_decoder.h"
+#include "draco/compression/point_cloud/point_cloud_decoder.h"
+#include "draco/core/draco_types.h"
+#include "draco/core/varint_decoding.h"
+
+namespace draco {
+
+// attribute, offset_dimensionality, data_type, data_size, num_components
+using AttributeTuple =
+    std::tuple<PointAttribute *, uint32_t, DataType, uint32_t, uint32_t>;
+
+// Output iterator that is used to decode values directly into the data buffer
+// of the modified PointAttribute.
+// The extension of this iterator beyond the DT_UINT32 concerns itself only with
+// the size of the data for efficiency, not the type.  DataType is conveyed in
+// but is an unused field populated for any future logic/special casing.
+// DT_UINT32 and all other 4-byte types are naturally supported from the size of
+// data in the kd tree encoder.  DT_UINT16 and DT_UINT8 are supported by way
+// of byte copies into a temporary memory buffer.
+template <class CoeffT>
+class PointAttributeVectorOutputIterator {
+  typedef PointAttributeVectorOutputIterator<CoeffT> Self;
+
+ public:
+  PointAttributeVectorOutputIterator(
+      PointAttributeVectorOutputIterator &&that) = default;
+
+  explicit PointAttributeVectorOutputIterator(
+      const std::vector<AttributeTuple> &atts)
+      : attributes_(atts), point_id_(0) {
+    DRACO_DCHECK_GE(atts.size(), 1);
+    uint32_t required_decode_bytes = 0;
+    for (auto index = 0; index < attributes_.size(); index++) {
+      const AttributeTuple &att = attributes_[index];
+      required_decode_bytes = (std::max)(required_decode_bytes,
+                                         std::get<3>(att) * std::get<4>(att));
+    }
+    memory_.resize(required_decode_bytes);
+    data_ = memory_.data();
+  }
+
+  const Self &operator++() {
+    ++point_id_;
+    return *this;
+  }
+
+  // We do not want to do ANY copying of this constructor so this particular
+  // operator is disabled for performance reasons.
+  // Self operator++(int) {
+  //   Self copy = *this;
+  //   ++point_id_;
+  //   return copy;
+  // }
+
+  Self &operator*() { return *this; }
+  // Still needed in some cases.
+  // TODO(hemmer): remove.
+  // hardcoded to 3 based on legacy usage.
+  const Self &operator=(const VectorD<CoeffT, 3> &val) {
+    DRACO_DCHECK_EQ(attributes_.size(), 1);  // Expect only ONE attribute.
+    AttributeTuple &att = attributes_[0];
+    PointAttribute *attribute = std::get<0>(att);
+    const uint32_t &offset = std::get<1>(att);
+    DRACO_DCHECK_EQ(offset, 0);  // expected to be zero
+    attribute->SetAttributeValue(attribute->mapped_index(point_id_),
+                                 &val[0] + offset);
+    return *this;
+  }
+  // Additional operator taking std::vector as argument.
+  const Self &operator=(const std::vector<CoeffT> &val) {
+    for (auto index = 0; index < attributes_.size(); index++) {
+      AttributeTuple &att = attributes_[index];
+      PointAttribute *attribute = std::get<0>(att);
+      const uint32_t &offset = std::get<1>(att);
+      const uint32_t &data_size = std::get<3>(att);
+      const uint32_t &num_components = std::get<4>(att);
+      const uint32_t *data_source = val.data() + offset;
+      if (data_size < 4) {  // handle uint16_t, uint8_t
+        // selectively copy data bytes
+        uint8_t *data_counter = data_;
+        for (uint32_t index = 0; index < num_components;
+             index += 1, data_counter += data_size) {
+          std::memcpy(data_counter, data_source + index, data_size);
+        }
+        // redirect to copied data
+        data_source = reinterpret_cast<uint32_t *>(data_);
+      }
+      const AttributeValueIndex avi = attribute->mapped_index(point_id_);
+      if (avi >= static_cast<uint32_t>(attribute->size())) {
+        return *this;
+      }
+      attribute->SetAttributeValue(avi, data_source);
+    }
+    return *this;
+  }
+
+ private:
+  // preallocated memory for buffering different data sizes.  Never reallocated.
+  std::vector<uint8_t> memory_;
+  uint8_t *data_;
+  std::vector<AttributeTuple> attributes_;
+  PointIndex point_id_;
+
+  // NO COPY
+  PointAttributeVectorOutputIterator(
+      const PointAttributeVectorOutputIterator &that) = delete;
+  PointAttributeVectorOutputIterator &operator=(
+      PointAttributeVectorOutputIterator const &) = delete;
+};
+
+KdTreeAttributesDecoder::KdTreeAttributesDecoder() {}
+
+bool KdTreeAttributesDecoder::DecodePortableAttributes(
+    DecoderBuffer *in_buffer) {
+  if (in_buffer->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 3)) {
+    // Old bitstream does everything in the
+    // DecodeDataNeededByPortableTransforms() method.
+    return true;
+  }
+  uint8_t compression_level = 0;
+  if (!in_buffer->Decode(&compression_level)) {
+    return false;
+  }
+  const int32_t num_points = GetDecoder()->point_cloud()->num_points();
+
+  // Decode data using the kd tree decoding into integer (portable) attributes.
+  // We first need to go over all attributes and create a new portable storage
+  // for those attributes that need it (floating point attributes that have to
+  // be dequantized after decoding).
+
+  const int num_attributes = GetNumAttributes();
+  uint32_t total_dimensionality = 0;  // position is a required dimension
+  std::vector<AttributeTuple> atts(num_attributes);
+
+  for (int i = 0; i < GetNumAttributes(); ++i) {
+    const int att_id = GetAttributeId(i);
+    PointAttribute *const att = GetDecoder()->point_cloud()->attribute(att_id);
+    // All attributes have the same number of values and identity mapping
+    // between PointIndex and AttributeValueIndex.
+    att->Reset(num_points);
+    att->SetIdentityMapping();
+
+    PointAttribute *target_att = nullptr;
+    if (att->data_type() == DT_UINT32 || att->data_type() == DT_UINT16 ||
+        att->data_type() == DT_UINT8) {
+      // We can decode to these attributes directly.
+      target_att = att;
+    } else if (att->data_type() == DT_INT32 || att->data_type() == DT_INT16 ||
+               att->data_type() == DT_INT8) {
+      // Prepare storage for data that is used to convert unsigned values back
+      // to the signed ones.
+      for (int c = 0; c < att->num_components(); ++c) {
+        min_signed_values_.push_back(0);
+      }
+      target_att = att;
+    } else if (att->data_type() == DT_FLOAT32) {
+      // Create a portable attribute that will hold the decoded data. We will
+      // dequantize the decoded data to the final attribute later on.
+      const int num_components = att->num_components();
+      GeometryAttribute va;
+      va.Init(att->attribute_type(), nullptr, num_components, DT_UINT32, false,
+              num_components * DataTypeLength(DT_UINT32), 0);
+      std::unique_ptr<PointAttribute> port_att(new PointAttribute(va));
+      port_att->SetIdentityMapping();
+      port_att->Reset(num_points);
+      quantized_portable_attributes_.push_back(std::move(port_att));
+      target_att = quantized_portable_attributes_.back().get();
+    } else {
+      // Unsupported type.
+      return false;
+    }
+    // Add attribute to the output iterator used by the core algorithm.
+    const DataType data_type = target_att->data_type();
+    const uint32_t data_size = (std::max)(0, DataTypeLength(data_type));
+    const uint32_t num_components = target_att->num_components();
+    atts[i] = std::make_tuple(target_att, total_dimensionality, data_type,
+                              data_size, num_components);
+    total_dimensionality += num_components;
+  }
+  PointAttributeVectorOutputIterator<uint32_t> out_it(atts);
+
+  switch (compression_level) {
+    case 0: {
+      DynamicIntegerPointsKdTreeDecoder<0> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 1: {
+      DynamicIntegerPointsKdTreeDecoder<1> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 2: {
+      DynamicIntegerPointsKdTreeDecoder<2> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 3: {
+      DynamicIntegerPointsKdTreeDecoder<3> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 4: {
+      DynamicIntegerPointsKdTreeDecoder<4> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 5: {
+      DynamicIntegerPointsKdTreeDecoder<5> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    case 6: {
+      DynamicIntegerPointsKdTreeDecoder<6> decoder(total_dimensionality);
+      if (!decoder.DecodePoints(in_buffer, out_it)) {
+        return false;
+      }
+      break;
+    }
+    default:
+      return false;
+  }
+  return true;
+}
+
+bool KdTreeAttributesDecoder::DecodeDataNeededByPortableTransforms(
+    DecoderBuffer *in_buffer) {
+  if (in_buffer->bitstream_version() >= DRACO_BITSTREAM_VERSION(2, 3)) {
+    // Decode quantization data for each attribute that need it.
+    // TODO(ostava): This should be moved to AttributeQuantizationTransform.
+    std::vector<float> min_value;
+    for (int i = 0; i < GetNumAttributes(); ++i) {
+      const int att_id = GetAttributeId(i);
+      const PointAttribute *const att =
+          GetDecoder()->point_cloud()->attribute(att_id);
+      if (att->data_type() == DT_FLOAT32) {
+        const int num_components = att->num_components();
+        min_value.resize(num_components);
+        if (!in_buffer->Decode(&min_value[0], sizeof(float) * num_components)) {
+          return false;
+        }
+        float max_value_dif;
+        if (!in_buffer->Decode(&max_value_dif)) {
+          return false;
+        }
+        uint8_t quantization_bits;
+        if (!in_buffer->Decode(&quantization_bits) || quantization_bits > 31) {
+          return false;
+        }
+        AttributeQuantizationTransform transform;
+        if (!transform.SetParameters(quantization_bits, min_value.data(),
+                                     num_components, max_value_dif)) {
+          return false;
+        }
+        const int num_transforms =
+            static_cast<int>(attribute_quantization_transforms_.size());
+        if (!transform.TransferToAttribute(
+                quantized_portable_attributes_[num_transforms].get())) {
+          return false;
+        }
+        attribute_quantization_transforms_.push_back(transform);
+      }
+    }
+
+    // Decode transform data for signed integer attributes.
+    for (int i = 0; i < min_signed_values_.size(); ++i) {
+      int32_t val;
+      if (!DecodeVarint(&val, in_buffer)) {
+        return false;
+      }
+      min_signed_values_[i] = val;
+    }
+    return true;
+  }
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  // Handle old bitstream
+  // Figure out the total dimensionality of the point cloud
+  const uint32_t attribute_count = GetNumAttributes();
+  uint32_t total_dimensionality = 0;  // position is a required dimension
+  std::vector<AttributeTuple> atts(attribute_count);
+  for (auto attribute_index = 0;
+       static_cast<uint32_t>(attribute_index) < attribute_count;
+       attribute_index += 1)  // increment the dimensionality as needed...
+  {
+    const int att_id = GetAttributeId(attribute_index);
+    PointAttribute *const att = GetDecoder()->point_cloud()->attribute(att_id);
+    const DataType data_type = att->data_type();
+    const uint32_t data_size = (std::max)(0, DataTypeLength(data_type));
+    const uint32_t num_components = att->num_components();
+    if (data_size > 4) {
+      return false;
+    }
+
+    atts[attribute_index] = std::make_tuple(
+        att, total_dimensionality, data_type, data_size, num_components);
+    // everything is treated as 32bit in the encoder.
+    total_dimensionality += num_components;
+  }
+
+  const int att_id = GetAttributeId(0);
+  PointAttribute *const att = GetDecoder()->point_cloud()->attribute(att_id);
+  att->SetIdentityMapping();
+  // Decode method
+  uint8_t method;
+  if (!in_buffer->Decode(&method)) {
+    return false;
+  }
+  if (method == KdTreeAttributesEncodingMethod::kKdTreeQuantizationEncoding) {
+    uint8_t compression_level = 0;
+    if (!in_buffer->Decode(&compression_level)) {
+      return false;
+    }
+    uint32_t num_points = 0;
+    if (!in_buffer->Decode(&num_points)) {
+      return false;
+    }
+    att->Reset(num_points);
+    FloatPointsTreeDecoder decoder;
+    decoder.set_num_points_from_header(num_points);
+    PointAttributeVectorOutputIterator<float> out_it(atts);
+    if (!decoder.DecodePointCloud(in_buffer, out_it)) {
+      return false;
+    }
+  } else if (method == KdTreeAttributesEncodingMethod::kKdTreeIntegerEncoding) {
+    uint8_t compression_level = 0;
+    if (!in_buffer->Decode(&compression_level)) {
+      return false;
+    }
+    if (6 < compression_level) {
+      DRACO_LOGE(
+          "KdTreeAttributesDecoder: compression level %i not supported.\n",
+          compression_level);
+      return false;
+    }
+
+    uint32_t num_points;
+    if (!in_buffer->Decode(&num_points)) {
+      return false;
+    }
+
+    for (auto attribute_index = 0;
+         static_cast<uint32_t>(attribute_index) < attribute_count;
+         attribute_index += 1) {
+      const int att_id = GetAttributeId(attribute_index);
+      PointAttribute *const attr =
+          GetDecoder()->point_cloud()->attribute(att_id);
+      attr->Reset(num_points);
+      attr->SetIdentityMapping();
+    };
+
+    PointAttributeVectorOutputIterator<uint32_t> out_it(atts);
+
+    switch (compression_level) {
+      case 0: {
+        DynamicIntegerPointsKdTreeDecoder<0> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 1: {
+        DynamicIntegerPointsKdTreeDecoder<1> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 2: {
+        DynamicIntegerPointsKdTreeDecoder<2> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 3: {
+        DynamicIntegerPointsKdTreeDecoder<3> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 4: {
+        DynamicIntegerPointsKdTreeDecoder<4> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 5: {
+        DynamicIntegerPointsKdTreeDecoder<5> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      case 6: {
+        DynamicIntegerPointsKdTreeDecoder<6> decoder(total_dimensionality);
+        if (!decoder.DecodePoints(in_buffer, out_it)) {
+          return false;
+        }
+        break;
+      }
+      default:
+        return false;
+    }
+  } else {
+    // Invalid method.
+    return false;
+  }
+  return true;
+#else
+  return false;
+#endif
+}
+
+template <typename SignedDataTypeT>
+bool KdTreeAttributesDecoder::TransformAttributeBackToSignedType(
+    PointAttribute *att, int num_processed_signed_components) {
+  typedef typename std::make_unsigned<SignedDataTypeT>::type UnsignedType;
+  std::vector<UnsignedType> unsigned_val(att->num_components());
+  std::vector<SignedDataTypeT> signed_val(att->num_components());
+
+  for (AttributeValueIndex avi(0); avi < static_cast<uint32_t>(att->size());
+       ++avi) {
+    att->GetValue(avi, &unsigned_val[0]);
+    for (int c = 0; c < att->num_components(); ++c) {
+      // Up-cast |unsigned_val| to int32_t to ensure we don't overflow it for
+      // smaller data types.
+      signed_val[c] = static_cast<SignedDataTypeT>(
+          static_cast<int32_t>(unsigned_val[c]) +
+          min_signed_values_[num_processed_signed_components + c]);
+    }
+    att->SetAttributeValue(avi, &signed_val[0]);
+  }
+  return true;
+}
+
+bool KdTreeAttributesDecoder::TransformAttributesToOriginalFormat() {
+  if (quantized_portable_attributes_.empty() && min_signed_values_.empty()) {
+    return true;
+  }
+  int num_processed_quantized_attributes = 0;
+  int num_processed_signed_components = 0;
+  // Dequantize attributes that needed it.
+  for (int i = 0; i < GetNumAttributes(); ++i) {
+    const int att_id = GetAttributeId(i);
+    PointAttribute *const att = GetDecoder()->point_cloud()->attribute(att_id);
+    if (att->data_type() == DT_INT32 || att->data_type() == DT_INT16 ||
+        att->data_type() == DT_INT8) {
+      std::vector<uint32_t> unsigned_val(att->num_components());
+      std::vector<int32_t> signed_val(att->num_components());
+      // Values are stored as unsigned in the attribute, make them signed again.
+      if (att->data_type() == DT_INT32) {
+        if (!TransformAttributeBackToSignedType<int32_t>(
+                att, num_processed_signed_components)) {
+          return false;
+        }
+      } else if (att->data_type() == DT_INT16) {
+        if (!TransformAttributeBackToSignedType<int16_t>(
+                att, num_processed_signed_components)) {
+          return false;
+        }
+      } else if (att->data_type() == DT_INT8) {
+        if (!TransformAttributeBackToSignedType<int8_t>(
+                att, num_processed_signed_components)) {
+          return false;
+        }
+      }
+      num_processed_signed_components += att->num_components();
+    } else if (att->data_type() == DT_FLOAT32) {
+      // TODO(ostava): This code should be probably moved out to attribute
+      // transform and shared with the SequentialQuantizationAttributeDecoder.
+
+      const PointAttribute *const src_att =
+          quantized_portable_attributes_[num_processed_quantized_attributes]
+              .get();
+
+      const AttributeQuantizationTransform &transform =
+          attribute_quantization_transforms_
+              [num_processed_quantized_attributes];
+
+      num_processed_quantized_attributes++;
+
+      if (GetDecoder()->options()->GetAttributeBool(
+              att->attribute_type(), "skip_attribute_transform", false)) {
+        // Attribute transform should not be performed. In this case, we replace
+        // the output geometry attribute with the portable attribute.
+        // TODO(ostava): We can potentially avoid this copy by introducing a new
+        // mechanism that would allow to use the final attributes as portable
+        // attributes for predictors that may need them.
+        att->CopyFrom(*src_att);
+        continue;
+      }
+
+      // Convert all quantized values back to floats.
+      const int32_t max_quantized_value =
+          (1u << static_cast<uint32_t>(transform.quantization_bits())) - 1;
+      const int num_components = att->num_components();
+      const int entry_size = sizeof(float) * num_components;
+      const std::unique_ptr<float[]> att_val(new float[num_components]);
+      int quant_val_id = 0;
+      int out_byte_pos = 0;
+      Dequantizer dequantizer;
+      if (!dequantizer.Init(transform.range(), max_quantized_value)) {
+        return false;
+      }
+      const uint32_t *const portable_attribute_data =
+          reinterpret_cast<const uint32_t *>(
+              src_att->GetAddress(AttributeValueIndex(0)));
+      for (uint32_t i = 0; i < src_att->size(); ++i) {
+        for (int c = 0; c < num_components; ++c) {
+          float value = dequantizer.DequantizeFloat(
+              portable_attribute_data[quant_val_id++]);
+          value = value + transform.min_value(c);
+          att_val[c] = value;
+        }
+        // Store the floating point value into the attribute buffer.
+        att->buffer()->Write(out_byte_pos, att_val.get(), entry_size);
+        out_byte_pos += entry_size;
+      }
+    }
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/kd_tree_attributes_decoder.h

@@ -0,0 +1,46 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_DECODER_H_
+
+#include "draco/attributes/attribute_quantization_transform.h"
+#include "draco/compression/attributes/attributes_decoder.h"
+
+namespace draco {
+
+// Decodes attributes encoded with the KdTreeAttributesEncoder.
+class KdTreeAttributesDecoder : public AttributesDecoder {
+ public:
+  KdTreeAttributesDecoder();
+
+ protected:
+  bool DecodePortableAttributes(DecoderBuffer *in_buffer) override;
+  bool DecodeDataNeededByPortableTransforms(DecoderBuffer *in_buffer) override;
+  bool TransformAttributesToOriginalFormat() override;
+
+ private:
+  template <typename SignedDataTypeT>
+  bool TransformAttributeBackToSignedType(PointAttribute *att,
+                                          int num_processed_signed_components);
+
+  std::vector<AttributeQuantizationTransform>
+      attribute_quantization_transforms_;
+  std::vector<int32_t> min_signed_values_;
+  std::vector<std::unique_ptr<PointAttribute>> quantized_portable_attributes_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/kd_tree_attributes_encoder.cc

@@ -0,0 +1,305 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/kd_tree_attributes_encoder.h"
+
+#include "draco/compression/attributes/kd_tree_attributes_shared.h"
+#include "draco/compression/attributes/point_d_vector.h"
+#include "draco/compression/point_cloud/algorithms/dynamic_integer_points_kd_tree_encoder.h"
+#include "draco/compression/point_cloud/algorithms/float_points_tree_encoder.h"
+#include "draco/compression/point_cloud/point_cloud_encoder.h"
+#include "draco/core/varint_encoding.h"
+
+namespace draco {
+
+KdTreeAttributesEncoder::KdTreeAttributesEncoder() : num_components_(0) {}
+
+KdTreeAttributesEncoder::KdTreeAttributesEncoder(int att_id)
+    : AttributesEncoder(att_id), num_components_(0) {}
+
+bool KdTreeAttributesEncoder::TransformAttributesToPortableFormat() {
+  // Convert any of the input attributes into a format that can be processed by
+  // the kd tree encoder (quantization of floating attributes for now).
+  const size_t num_points = encoder()->point_cloud()->num_points();
+  int num_components = 0;
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    const int att_id = GetAttributeId(i);
+    const PointAttribute *const att =
+        encoder()->point_cloud()->attribute(att_id);
+    num_components += att->num_components();
+  }
+  num_components_ = num_components;
+
+  // Go over all attributes and quantize them if needed.
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    const int att_id = GetAttributeId(i);
+    const PointAttribute *const att =
+        encoder()->point_cloud()->attribute(att_id);
+    if (att->data_type() == DT_FLOAT32) {
+      // Quantization path.
+      AttributeQuantizationTransform attribute_quantization_transform;
+      const int quantization_bits = encoder()->options()->GetAttributeInt(
+          att_id, "quantization_bits", -1);
+      if (quantization_bits < 1) {
+        return false;
+      }
+      if (encoder()->options()->IsAttributeOptionSet(att_id,
+                                                     "quantization_origin") &&
+          encoder()->options()->IsAttributeOptionSet(att_id,
+                                                     "quantization_range")) {
+        // Quantization settings are explicitly specified in the provided
+        // options.
+        std::vector<float> quantization_origin(att->num_components());
+        encoder()->options()->GetAttributeVector(att_id, "quantization_origin",
+                                                 att->num_components(),
+                                                 &quantization_origin[0]);
+        const float range = encoder()->options()->GetAttributeFloat(
+            att_id, "quantization_range", 1.f);
+        attribute_quantization_transform.SetParameters(
+            quantization_bits, quantization_origin.data(),
+            att->num_components(), range);
+      } else {
+        // Compute quantization settings from the attribute values.
+        if (!attribute_quantization_transform.ComputeParameters(
+                *att, quantization_bits)) {
+          return false;
+        }
+      }
+      attribute_quantization_transforms_.push_back(
+          attribute_quantization_transform);
+      // Store the quantized attribute in an array that will be used when we do
+      // the actual encoding of the data.
+      auto portable_att =
+          attribute_quantization_transform.InitTransformedAttribute(*att,
+                                                                    num_points);
+      attribute_quantization_transform.TransformAttribute(*att, {},
+                                                          portable_att.get());
+      quantized_portable_attributes_.push_back(std::move(portable_att));
+    } else if (att->data_type() == DT_INT32 || att->data_type() == DT_INT16 ||
+               att->data_type() == DT_INT8) {
+      // For signed types, find the minimum value for each component. These
+      // values are going to be used to transform the attribute values to
+      // unsigned integers that can be processed by the core kd tree algorithm.
+      std::vector<int32_t> min_value(att->num_components(),
+                                     std::numeric_limits<int32_t>::max());
+      std::vector<int32_t> act_value(att->num_components());
+      for (AttributeValueIndex avi(0); avi < static_cast<uint32_t>(att->size());
+           ++avi) {
+        att->ConvertValue<int32_t>(avi, &act_value[0]);
+        for (int c = 0; c < att->num_components(); ++c) {
+          if (min_value[c] > act_value[c]) {
+            min_value[c] = act_value[c];
+          }
+        }
+      }
+      for (int c = 0; c < att->num_components(); ++c) {
+        min_signed_values_.push_back(min_value[c]);
+      }
+    }
+  }
+  return true;
+}
+
+bool KdTreeAttributesEncoder::EncodeDataNeededByPortableTransforms(
+    EncoderBuffer *out_buffer) {
+  // Store quantization settings for all attributes that need it.
+  for (int i = 0; i < attribute_quantization_transforms_.size(); ++i) {
+    attribute_quantization_transforms_[i].EncodeParameters(out_buffer);
+  }
+
+  // Encode data needed for transforming signed integers to unsigned ones.
+  for (int i = 0; i < min_signed_values_.size(); ++i) {
+    EncodeVarint<int32_t>(min_signed_values_[i], out_buffer);
+  }
+  return true;
+}
+
+bool KdTreeAttributesEncoder::EncodePortableAttributes(
+    EncoderBuffer *out_buffer) {
+  // Encode the data using the kd tree encoder algorithm. The data is first
+  // copied to a PointDVector that provides all the API expected by the core
+  // encoding algorithm.
+
+  // We limit the maximum value of compression_level to 6 as we don't currently
+  // have viable algorithms for higher compression levels.
+  uint8_t compression_level =
+      std::min(10 - encoder()->options()->GetSpeed(), 6);
+  DRACO_DCHECK_LE(compression_level, 6);
+
+  if (compression_level == 6 && num_components_ > 15) {
+    // Don't use compression level for CL >= 6. Axis selection is currently
+    // encoded using 4 bits.
+    compression_level = 5;
+  }
+
+  out_buffer->Encode(compression_level);
+
+  // Init PointDVector. The number of dimensions is equal to the total number
+  // of dimensions across all attributes.
+  const int num_points = encoder()->point_cloud()->num_points();
+  PointDVector<uint32_t> point_vector(num_points, num_components_);
+
+  int num_processed_components = 0;
+  int num_processed_quantized_attributes = 0;
+  int num_processed_signed_components = 0;
+  // Copy data to the point vector.
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    const int att_id = GetAttributeId(i);
+    const PointAttribute *const att =
+        encoder()->point_cloud()->attribute(att_id);
+    const PointAttribute *source_att = nullptr;
+    if (att->data_type() == DT_UINT32 || att->data_type() == DT_UINT16 ||
+        att->data_type() == DT_UINT8 || att->data_type() == DT_INT32 ||
+        att->data_type() == DT_INT16 || att->data_type() == DT_INT8) {
+      // Use the original attribute.
+      source_att = att;
+    } else if (att->data_type() == DT_FLOAT32) {
+      // Use the portable (quantized) attribute instead.
+      source_att =
+          quantized_portable_attributes_[num_processed_quantized_attributes]
+              .get();
+      num_processed_quantized_attributes++;
+    } else {
+      // Unsupported data type.
+      return false;
+    }
+
+    if (source_att == nullptr) {
+      return false;
+    }
+
+    // Copy source_att to the vector.
+    if (source_att->data_type() == DT_UINT32) {
+      // If the data type is the same as the one used by the point vector, we
+      // can directly copy individual elements.
+      for (PointIndex pi(0); pi < num_points; ++pi) {
+        const AttributeValueIndex avi = source_att->mapped_index(pi);
+        const uint8_t *const att_value_address = source_att->GetAddress(avi);
+        point_vector.CopyAttribute(source_att->num_components(),
+                                   num_processed_components, pi.value(),
+                                   att_value_address);
+      }
+    } else if (source_att->data_type() == DT_INT32 ||
+               source_att->data_type() == DT_INT16 ||
+               source_att->data_type() == DT_INT8) {
+      // Signed values need to be converted to unsigned before they are stored
+      // in the point vector.
+      std::vector<int32_t> signed_point(source_att->num_components());
+      std::vector<uint32_t> unsigned_point(source_att->num_components());
+      for (PointIndex pi(0); pi < num_points; ++pi) {
+        const AttributeValueIndex avi = source_att->mapped_index(pi);
+        source_att->ConvertValue<int32_t>(avi, &signed_point[0]);
+        for (int c = 0; c < source_att->num_components(); ++c) {
+          unsigned_point[c] =
+              signed_point[c] -
+              min_signed_values_[num_processed_signed_components + c];
+        }
+
+        point_vector.CopyAttribute(source_att->num_components(),
+                                   num_processed_components, pi.value(),
+                                   &unsigned_point[0]);
+      }
+      num_processed_signed_components += source_att->num_components();
+    } else {
+      // If the data type of the attribute is different, we have to convert the
+      // value before we put it to the point vector.
+      std::vector<uint32_t> point(source_att->num_components());
+      for (PointIndex pi(0); pi < num_points; ++pi) {
+        const AttributeValueIndex avi = source_att->mapped_index(pi);
+        source_att->ConvertValue<uint32_t>(avi, &point[0]);
+        point_vector.CopyAttribute(source_att->num_components(),
+                                   num_processed_components, pi.value(),
+                                   point.data());
+      }
+    }
+    num_processed_components += source_att->num_components();
+  }
+
+  // Compute the maximum bit length needed for the kd tree encoding.
+  int num_bits = 0;
+  const uint32_t *data = point_vector[0];
+  for (int i = 0; i < num_points * num_components_; ++i) {
+    if (data[i] > 0) {
+      const int msb = MostSignificantBit(data[i]) + 1;
+      if (msb > num_bits) {
+        num_bits = msb;
+      }
+    }
+  }
+
+  switch (compression_level) {
+    case 6: {
+      DynamicIntegerPointsKdTreeEncoder<6> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 5: {
+      DynamicIntegerPointsKdTreeEncoder<5> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 4: {
+      DynamicIntegerPointsKdTreeEncoder<4> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 3: {
+      DynamicIntegerPointsKdTreeEncoder<3> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 2: {
+      DynamicIntegerPointsKdTreeEncoder<2> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 1: {
+      DynamicIntegerPointsKdTreeEncoder<1> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    case 0: {
+      DynamicIntegerPointsKdTreeEncoder<0> points_encoder(num_components_);
+      if (!points_encoder.EncodePoints(point_vector.begin(), point_vector.end(),
+                                       num_bits, out_buffer)) {
+        return false;
+      }
+      break;
+    }
+    // Compression level and/or encoding speed seem wrong.
+    default:
+      return false;
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/kd_tree_attributes_encoder.h

@@ -0,0 +1,51 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_ENCODER_H_
+
+#include "draco/attributes/attribute_quantization_transform.h"
+#include "draco/compression/attributes/attributes_encoder.h"
+#include "draco/compression/config/compression_shared.h"
+
+namespace draco {
+
+// Encodes all attributes of a given PointCloud using one of the available
+// Kd-tree compression methods.
+// See compression/point_cloud/point_cloud_kd_tree_encoder.h for more details.
+class KdTreeAttributesEncoder : public AttributesEncoder {
+ public:
+  KdTreeAttributesEncoder();
+  explicit KdTreeAttributesEncoder(int att_id);
+
+  uint8_t GetUniqueId() const override { return KD_TREE_ATTRIBUTE_ENCODER; }
+
+ protected:
+  bool TransformAttributesToPortableFormat() override;
+  bool EncodePortableAttributes(EncoderBuffer *out_buffer) override;
+  bool EncodeDataNeededByPortableTransforms(EncoderBuffer *out_buffer) override;
+
+ private:
+  std::vector<AttributeQuantizationTransform>
+      attribute_quantization_transforms_;
+  // Min signed values are used to transform signed integers into unsigned ones
+  // (by subtracting the min signed value for each component).
+  std::vector<int32_t> min_signed_values_;
+  std::vector<std::unique_ptr<PointAttribute>> quantized_portable_attributes_;
+  int num_components_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/kd_tree_attributes_shared.h

@@ -0,0 +1,28 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_SHARED_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_SHARED_H_
+
+namespace draco {
+
+// Defines types of kD-tree compression
+enum KdTreeAttributesEncodingMethod {
+  kKdTreeQuantizationEncoding = 0,
+  kKdTreeIntegerEncoding
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_KD_TREE_ATTRIBUTES_SHARED_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/linear_sequencer.h

@@ -0,0 +1,51 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_LINEAR_SEQUENCER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_LINEAR_SEQUENCER_H_
+
+#include "draco/compression/attributes/points_sequencer.h"
+
+namespace draco {
+
+// A simple sequencer that generates a linear sequence [0, num_points - 1].
+// I.e., the order of the points is preserved for the input data.
+class LinearSequencer : public PointsSequencer {
+ public:
+  explicit LinearSequencer(int32_t num_points) : num_points_(num_points) {}
+
+  bool UpdatePointToAttributeIndexMapping(PointAttribute *attribute) override {
+    attribute->SetIdentityMapping();
+    return true;
+  }
+
+ protected:
+  bool GenerateSequenceInternal() override {
+    if (num_points_ < 0) {
+      return false;
+    }
+    out_point_ids()->resize(num_points_);
+    for (int i = 0; i < num_points_; ++i) {
+      out_point_ids()->at(i) = PointIndex(i);
+    }
+    return true;
+  }
+
+ private:
+  int32_t num_points_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_LINEAR_SEQUENCER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/mesh_attribute_indices_encoding_data.h

@@ -0,0 +1,58 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_MESH_ATTRIBUTE_INDICES_ENCODING_DATA_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_MESH_ATTRIBUTE_INDICES_ENCODING_DATA_H_
+
+#include <inttypes.h>
+
+#include <vector>
+
+#include "draco/attributes/geometry_indices.h"
+
+namespace draco {
+
+// Data used for encoding and decoding of mesh attributes.
+struct MeshAttributeIndicesEncodingData {
+  MeshAttributeIndicesEncodingData() : num_values(0) {}
+
+  void Init(int num_vertices) {
+    vertex_to_encoded_attribute_value_index_map.resize(num_vertices);
+
+    // We expect to store one value for each vertex.
+    encoded_attribute_value_index_to_corner_map.reserve(num_vertices);
+  }
+
+  // Array for storing the corner ids in the order their associated attribute
+  // entries were encoded/decoded. For every encoded attribute value entry we
+  // store exactly one corner. I.e., this is the mapping between an encoded
+  // attribute entry ids and corner ids. This map is needed for example by
+  // prediction schemes. Note that not all corners are included in this map,
+  // e.g., if multiple corners share the same attribute value, only one of these
+  // corners will be usually included.
+  std::vector<CornerIndex> encoded_attribute_value_index_to_corner_map;
+
+  // Map for storing encoding order of attribute entries for each vertex.
+  // i.e. Mapping between vertices and their corresponding attribute entry ids
+  // that are going to be used by the decoder.
+  // -1 if an attribute entry hasn't been encoded/decoded yet.
+  std::vector<int32_t> vertex_to_encoded_attribute_value_index_map;
+
+  // Total number of encoded/decoded attribute entries.
+  int num_values;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_MESH_ATTRIBUTE_INDICES_ENCODING_DATA_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/normal_compression_utils.h

@@ -0,0 +1,360 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Utilities for converting unit vectors to octahedral coordinates and back.
+// For more details about octahedral coordinates, see for example Cigolle
+// et al.'14 “A Survey of Efficient Representations for Independent Unit
+// Vectors”.
+//
+// In short this is motivated by an octahedron inscribed into a sphere. The
+// direction of the normal vector can be defined by a point on the octahedron.
+// On the right hemisphere (x > 0) this point is projected onto the x = 0 plane,
+// that is, the right side of the octahedron forms a diamond like shape. The
+// left side of the octahedron is also projected onto the x = 0 plane, however,
+// in this case we flap the triangles of the diamond outward. Afterwards we
+// shift the resulting square such that all values are positive.
+//
+// Important values in this file:
+// * q: number of quantization bits
+// * max_quantized_value: the max value representable with q bits (odd)
+// * max_value: max value of the diamond = max_quantized_value - 1  (even)
+// * center_value: center of the diamond after shift
+//
+// Note that the parameter space is somewhat periodic, e.g. (0, 0) ==
+// (max_value, max_value), which is also why the diamond is one smaller than the
+// maximal representable value in order to have an odd range of values.
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_NORMAL_COMPRESSION_UTILS_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_NORMAL_COMPRESSION_UTILS_H_
+
+#include <inttypes.h>
+
+#include <algorithm>
+#include <cmath>
+
+#include "draco/core/macros.h"
+
+namespace draco {
+
+class OctahedronToolBox {
+ public:
+  OctahedronToolBox()
+      : quantization_bits_(-1),
+        max_quantized_value_(-1),
+        max_value_(-1),
+        dequantization_scale_(1.f),
+        center_value_(-1) {}
+
+  bool SetQuantizationBits(int32_t q) {
+    if (q < 2 || q > 30) {
+      return false;
+    }
+    quantization_bits_ = q;
+    max_quantized_value_ = (1 << quantization_bits_) - 1;
+    max_value_ = max_quantized_value_ - 1;
+    dequantization_scale_ = 2.f / max_value_;
+    center_value_ = max_value_ / 2;
+    return true;
+  }
+  bool IsInitialized() const { return quantization_bits_ != -1; }
+
+  // Convert all edge points in the top left and bottom right quadrants to
+  // their corresponding position in the bottom left and top right quadrants.
+  // Convert all corner edge points to the top right corner.
+  inline void CanonicalizeOctahedralCoords(int32_t s, int32_t t, int32_t *out_s,
+                                           int32_t *out_t) const {
+    if ((s == 0 && t == 0) || (s == 0 && t == max_value_) ||
+        (s == max_value_ && t == 0)) {
+      s = max_value_;
+      t = max_value_;
+    } else if (s == 0 && t > center_value_) {
+      t = center_value_ - (t - center_value_);
+    } else if (s == max_value_ && t < center_value_) {
+      t = center_value_ + (center_value_ - t);
+    } else if (t == max_value_ && s < center_value_) {
+      s = center_value_ + (center_value_ - s);
+    } else if (t == 0 && s > center_value_) {
+      s = center_value_ - (s - center_value_);
+    }
+
+    *out_s = s;
+    *out_t = t;
+  }
+
+  // Converts an integer vector to octahedral coordinates.
+  // Precondition: |int_vec| abs sum must equal center value.
+  inline void IntegerVectorToQuantizedOctahedralCoords(const int32_t *int_vec,
+                                                       int32_t *out_s,
+                                                       int32_t *out_t) const {
+    DRACO_DCHECK_EQ(
+        std::abs(int_vec[0]) + std::abs(int_vec[1]) + std::abs(int_vec[2]),
+        center_value_);
+    int32_t s, t;
+    if (int_vec[0] >= 0) {
+      // Right hemisphere.
+      s = (int_vec[1] + center_value_);
+      t = (int_vec[2] + center_value_);
+    } else {
+      // Left hemisphere.
+      if (int_vec[1] < 0) {
+        s = std::abs(int_vec[2]);
+      } else {
+        s = (max_value_ - std::abs(int_vec[2]));
+      }
+      if (int_vec[2] < 0) {
+        t = std::abs(int_vec[1]);
+      } else {
+        t = (max_value_ - std::abs(int_vec[1]));
+      }
+    }
+    CanonicalizeOctahedralCoords(s, t, out_s, out_t);
+  }
+
+  template <class T>
+  void FloatVectorToQuantizedOctahedralCoords(const T *vector, int32_t *out_s,
+                                              int32_t *out_t) const {
+    const double abs_sum = std::abs(static_cast<double>(vector[0])) +
+                           std::abs(static_cast<double>(vector[1])) +
+                           std::abs(static_cast<double>(vector[2]));
+
+    // Adjust values such that abs sum equals 1.
+    double scaled_vector[3];
+    if (abs_sum > 1e-6) {
+      // Scale needed to project the vector to the surface of an octahedron.
+      const double scale = 1.0 / abs_sum;
+      scaled_vector[0] = vector[0] * scale;
+      scaled_vector[1] = vector[1] * scale;
+      scaled_vector[2] = vector[2] * scale;
+    } else {
+      scaled_vector[0] = 1.0;
+      scaled_vector[1] = 0;
+      scaled_vector[2] = 0;
+    }
+
+    // Scale vector such that the sum equals the center value.
+    int32_t int_vec[3];
+    int_vec[0] =
+        static_cast<int32_t>(floor(scaled_vector[0] * center_value_ + 0.5));
+    int_vec[1] =
+        static_cast<int32_t>(floor(scaled_vector[1] * center_value_ + 0.5));
+    // Make sure the sum is exactly the center value.
+    int_vec[2] = center_value_ - std::abs(int_vec[0]) - std::abs(int_vec[1]);
+    if (int_vec[2] < 0) {
+      // If the sum of first two coordinates is too large, we need to decrease
+      // the length of one of the coordinates.
+      if (int_vec[1] > 0) {
+        int_vec[1] += int_vec[2];
+      } else {
+        int_vec[1] -= int_vec[2];
+      }
+      int_vec[2] = 0;
+    }
+    // Take care of the sign.
+    if (scaled_vector[2] < 0) {
+      int_vec[2] *= -1;
+    }
+
+    IntegerVectorToQuantizedOctahedralCoords(int_vec, out_s, out_t);
+  }
+
+  // Normalize |vec| such that its abs sum is equal to the center value;
+  template <class T>
+  void CanonicalizeIntegerVector(T *vec) const {
+    static_assert(std::is_integral<T>::value, "T must be an integral type.");
+    static_assert(std::is_signed<T>::value, "T must be a signed type.");
+    const int64_t abs_sum = static_cast<int64_t>(std::abs(vec[0])) +
+                            static_cast<int64_t>(std::abs(vec[1])) +
+                            static_cast<int64_t>(std::abs(vec[2]));
+
+    if (abs_sum == 0) {
+      vec[0] = center_value_;  // vec[1] == v[2] == 0
+    } else {
+      vec[0] =
+          (static_cast<int64_t>(vec[0]) * static_cast<int64_t>(center_value_)) /
+          abs_sum;
+      vec[1] =
+          (static_cast<int64_t>(vec[1]) * static_cast<int64_t>(center_value_)) /
+          abs_sum;
+      if (vec[2] >= 0) {
+        vec[2] = center_value_ - std::abs(vec[0]) - std::abs(vec[1]);
+      } else {
+        vec[2] = -(center_value_ - std::abs(vec[0]) - std::abs(vec[1]));
+      }
+    }
+  }
+
+  inline void QuantizedOctahedralCoordsToUnitVector(int32_t in_s, int32_t in_t,
+                                                    float *out_vector) const {
+    OctahedralCoordsToUnitVector(in_s * dequantization_scale_ - 1.f,
+                                 in_t * dequantization_scale_ - 1.f,
+                                 out_vector);
+  }
+
+  // |s| and |t| are expected to be signed values.
+  inline bool IsInDiamond(const int32_t &s, const int32_t &t) const {
+    // Expect center already at origin.
+    DRACO_DCHECK_LE(s, center_value_);
+    DRACO_DCHECK_LE(t, center_value_);
+    DRACO_DCHECK_GE(s, -center_value_);
+    DRACO_DCHECK_GE(t, -center_value_);
+    return std::abs(s) + std::abs(t) <= center_value_;
+  }
+
+  void InvertDiamond(int32_t *s, int32_t *t) const {
+    // Expect center already at origin.
+    DRACO_DCHECK_LE(*s, center_value_);
+    DRACO_DCHECK_LE(*t, center_value_);
+    DRACO_DCHECK_GE(*s, -center_value_);
+    DRACO_DCHECK_GE(*t, -center_value_);
+    int32_t sign_s = 0;
+    int32_t sign_t = 0;
+    if (*s >= 0 && *t >= 0) {
+      sign_s = 1;
+      sign_t = 1;
+    } else if (*s <= 0 && *t <= 0) {
+      sign_s = -1;
+      sign_t = -1;
+    } else {
+      sign_s = (*s > 0) ? 1 : -1;
+      sign_t = (*t > 0) ? 1 : -1;
+    }
+
+    const int32_t corner_point_s = sign_s * center_value_;
+    const int32_t corner_point_t = sign_t * center_value_;
+    *s = 2 * *s - corner_point_s;
+    *t = 2 * *t - corner_point_t;
+    if (sign_s * sign_t >= 0) {
+      int32_t temp = *s;
+      *s = -*t;
+      *t = -temp;
+    } else {
+      std::swap(*s, *t);
+    }
+    *s = (*s + corner_point_s) / 2;
+    *t = (*t + corner_point_t) / 2;
+  }
+
+  void InvertDirection(int32_t *s, int32_t *t) const {
+    // Expect center already at origin.
+    DRACO_DCHECK_LE(*s, center_value_);
+    DRACO_DCHECK_LE(*t, center_value_);
+    DRACO_DCHECK_GE(*s, -center_value_);
+    DRACO_DCHECK_GE(*t, -center_value_);
+    *s *= -1;
+    *t *= -1;
+    this->InvertDiamond(s, t);
+  }
+
+  // For correction values.
+  int32_t ModMax(int32_t x) const {
+    if (x > this->center_value()) {
+      return x - this->max_quantized_value();
+    }
+    if (x < -this->center_value()) {
+      return x + this->max_quantized_value();
+    }
+    return x;
+  }
+
+  // For correction values.
+  int32_t MakePositive(int32_t x) const {
+    DRACO_DCHECK_LE(x, this->center_value() * 2);
+    if (x < 0) {
+      return x + this->max_quantized_value();
+    }
+    return x;
+  }
+
+  int32_t quantization_bits() const { return quantization_bits_; }
+  int32_t max_quantized_value() const { return max_quantized_value_; }
+  int32_t max_value() const { return max_value_; }
+  int32_t center_value() const { return center_value_; }
+
+ private:
+  inline void OctahedralCoordsToUnitVector(float in_s_scaled, float in_t_scaled,
+                                           float *out_vector) const {
+    // Background about the encoding:
+    //   A normal is encoded in a normalized space <s, t> depicted below. The
+    //   encoding correponds to an octahedron that is unwrapped to a 2D plane.
+    //   During encoding, a normal is projected to the surface of the octahedron
+    //   and the projection is then unwrapped to the 2D plane. Decoding is the
+    //   reverse of this process.
+    //   All points in the central diamond are located on triangles on the
+    //   right "hemisphere" of the octahedron while all points outside of the
+    //   diamond are on the left hemisphere (basically, they would have to be
+    //   wrapped along the diagonal edges to form the octahedron). The central
+    //   point corresponds to the right most vertex of the octahedron and all
+    //   corners of the plane correspond to the left most vertex of the
+    //   octahedron.
+    //
+    // t
+    // ^ *-----*-----*
+    // | |    /|\    |
+    //   |   / | \   |
+    //   |  /  |  \  |
+    //   | /   |   \ |
+    //   *-----*---- *
+    //   | \   |   / |
+    //   |  \  |  /  |
+    //   |   \ | /   |
+    //   |    \|/    |
+    //   *-----*-----*  --> s
+
+    // Note that the input |in_s_scaled| and |in_t_scaled| are already scaled to
+    // <-1, 1> range. This way, the central point is at coordinate (0, 0).
+    float y = in_s_scaled;
+    float z = in_t_scaled;
+
+    // Remaining coordinate can be computed by projecting the (y, z) values onto
+    // the surface of the octahedron.
+    const float x = 1.f - abs(y) - abs(z);
+
+    // |x| is essentially a signed distance from the diagonal edges of the
+    // diamond shown on the figure above. It is positive for all points in the
+    // diamond (right hemisphere) and negative for all points outside the
+    // diamond (left hemisphere). For all points on the left hemisphere we need
+    // to update their (y, z) coordinates to account for the wrapping along
+    // the edges of the diamond.
+    float x_offset = -x;
+    x_offset = x_offset < 0 ? 0 : x_offset;
+
+    // This will do nothing for the points on the right hemisphere but it will
+    // mirror the (y, z) location along the nearest diagonal edge of the
+    // diamond.
+    y += y < 0 ? x_offset : -x_offset;
+    z += z < 0 ? x_offset : -x_offset;
+
+    // Normalize the computed vector.
+    const float norm_squared = x * x + y * y + z * z;
+    if (norm_squared < 1e-6) {
+      out_vector[0] = 0;
+      out_vector[1] = 0;
+      out_vector[2] = 0;
+    } else {
+      const float d = 1.0f / std::sqrt(norm_squared);
+      out_vector[0] = x * d;
+      out_vector[1] = y * d;
+      out_vector[2] = z * d;
+    }
+  }
+
+  int32_t quantization_bits_;
+  int32_t max_quantized_value_;
+  int32_t max_value_;
+  float dequantization_scale_;
+  int32_t center_value_;
+};
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_NORMAL_COMPRESSION_UTILS_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/point_d_vector.h

@@ -0,0 +1,279 @@
+// Copyright 2018 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_POINT_D_VECTOR_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_POINT_D_VECTOR_H_
+
+#include <cstring>
+#include <memory>
+#include <vector>
+
+#include "draco/core/macros.h"
+
+namespace draco {
+
+// The main class of this file is PointDVector providing an interface similar to
+// std::vector<PointD> for arbitrary number of dimensions (without a template
+// argument). PointDVectorIterator is a random access iterator, which allows for
+// compatibility with existing algorithms. PseudoPointD provides for a view on
+// the individual items in a contiguous block of memory, which is compatible
+// with the swap function and is returned by a dereference of
+// PointDVectorIterator. Swap functions provide for compatibility/specialization
+// that allows these classes to work with currently utilized STL functions.
+
+// This class allows for swap functionality from the RandomIterator
+// It seems problematic to bring this inside PointDVector due to templating.
+template <typename internal_t>
+class PseudoPointD {
+ public:
+  PseudoPointD(internal_t *mem, internal_t dimension)
+      : mem_(mem), dimension_(dimension) {}
+
+  // Specifically copies referenced memory
+  void swap(PseudoPointD &other) noexcept {
+    for (internal_t dim = 0; dim < dimension_; dim += 1) {
+      std::swap(mem_[dim], other.mem_[dim]);
+    }
+  }
+
+  PseudoPointD(const PseudoPointD &other)
+      : mem_(other.mem_), dimension_(other.dimension_) {}
+
+  const internal_t &operator[](const size_t &n) const {
+    DRACO_DCHECK_LT(n, dimension_);
+    return mem_[n];
+  }
+  internal_t &operator[](const size_t &n) {
+    DRACO_DCHECK_LT(n, dimension_);
+    return mem_[n];
+  }
+
+  bool operator==(const PseudoPointD &other) const {
+    for (auto dim = 0; dim < dimension_; dim += 1) {
+      if (mem_[dim] != other.mem_[dim]) {
+        return false;
+      }
+    }
+    return true;
+  }
+  bool operator!=(const PseudoPointD &other) const {
+    return !this->operator==(other);
+  }
+
+ private:
+  internal_t *const mem_;
+  const internal_t dimension_;
+};
+
+// It seems problematic to bring this inside PointDVector due to templating.
+template <typename internal_t>
+void swap(draco::PseudoPointD<internal_t> &&a,
+          draco::PseudoPointD<internal_t> &&b) noexcept {
+  a.swap(b);
+};
+template <typename internal_t>
+void swap(draco::PseudoPointD<internal_t> &a,
+          draco::PseudoPointD<internal_t> &b) noexcept {
+  a.swap(b);
+};
+
+template <typename internal_t>
+class PointDVector {
+ public:
+  PointDVector(const uint32_t n_items, const uint32_t dimensionality)
+      : n_items_(n_items),
+        dimensionality_(dimensionality),
+        item_size_bytes_(dimensionality * sizeof(internal_t)),
+        data_(n_items * dimensionality),
+        data0_(data_.data()) {}
+  // random access iterator
+  class PointDVectorIterator
+      : public std::iterator<std::random_access_iterator_tag, size_t, size_t> {
+    friend class PointDVector;
+
+   public:
+    // std::iter_swap is called inside of std::partition and needs this
+    // specialized support
+    PseudoPointD<internal_t> operator*() const {
+      return PseudoPointD<internal_t>(vec_->data0_ + item_ * dimensionality_,
+                                      dimensionality_);
+    }
+    const PointDVectorIterator &operator++() {
+      item_ += 1;
+      return *this;
+    }
+    const PointDVectorIterator &operator--() {
+      item_ -= 1;
+      return *this;
+    }
+    PointDVectorIterator operator++(int32_t) {
+      PointDVectorIterator copy(*this);
+      item_ += 1;
+      return copy;
+    }
+    PointDVectorIterator operator--(int32_t) {
+      PointDVectorIterator copy(*this);
+      item_ -= 1;
+      return copy;
+    }
+    PointDVectorIterator &operator=(const PointDVectorIterator &other) {
+      this->item_ = other.item_;
+      return *this;
+    }
+
+    bool operator==(const PointDVectorIterator &ref) const {
+      return item_ == ref.item_;
+    }
+    bool operator!=(const PointDVectorIterator &ref) const {
+      return item_ != ref.item_;
+    }
+    bool operator<(const PointDVectorIterator &ref) const {
+      return item_ < ref.item_;
+    }
+    bool operator>(const PointDVectorIterator &ref) const {
+      return item_ > ref.item_;
+    }
+    bool operator<=(const PointDVectorIterator &ref) const {
+      return item_ <= ref.item_;
+    }
+    bool operator>=(const PointDVectorIterator &ref) const {
+      return item_ >= ref.item_;
+    }
+
+    PointDVectorIterator operator+(const int32_t &add) const {
+      PointDVectorIterator copy(vec_, item_ + add);
+      return copy;
+    }
+    PointDVectorIterator &operator+=(const int32_t &add) {
+      item_ += add;
+      return *this;
+    }
+    PointDVectorIterator operator-(const int32_t &sub) const {
+      PointDVectorIterator copy(vec_, item_ - sub);
+      return copy;
+    }
+    size_t operator-(const PointDVectorIterator &sub) const {
+      return (item_ - sub.item_);
+    }
+
+    PointDVectorIterator &operator-=(const int32_t &sub) {
+      item_ -= sub;
+      return *this;
+    }
+
+    internal_t *operator[](const size_t &n) const {
+      return vec_->data0_ + (item_ + n) * dimensionality_;
+    }
+
+   protected:
+    explicit PointDVectorIterator(PointDVector *vec, size_t start_item)
+        : item_(start_item), vec_(vec), dimensionality_(vec->dimensionality_) {}
+
+   private:
+    size_t item_;  // this counts the item that should be referenced.
+    PointDVector *const vec_;        // the thing that we're iterating on
+    const uint32_t dimensionality_;  // local copy from vec_
+  };
+
+  PointDVectorIterator begin() { return PointDVectorIterator(this, 0); }
+  PointDVectorIterator end() { return PointDVectorIterator(this, n_items_); }
+
+  // operator[] allows for unprotected user-side usage of operator[] on the
+  // return value AS IF it were a natively indexable type like Point3*
+  internal_t *operator[](const uint32_t index) {
+    DRACO_DCHECK_LT(index, n_items_);
+    return data0_ + index * dimensionality_;
+  }
+  const internal_t *operator[](const uint32_t index) const {
+    DRACO_DCHECK_LT(index, n_items_);
+    return data0_ + index * dimensionality_;
+  }
+
+  uint32_t size() const { return n_items_; }
+  size_t GetBufferSize() const { return data_.size(); }
+
+  // copy a single contiguous 'item' from one PointDVector into this one.
+  void CopyItem(const PointDVector &source, const internal_t source_index,
+                const internal_t destination_index) {
+    DRACO_DCHECK(&source != this ||
+                 (&source == this && source_index != destination_index));
+    DRACO_DCHECK_LT(destination_index, n_items_);
+    DRACO_DCHECK_LT(source_index, source.n_items_);
+
+    // DRACO_DCHECK_EQ(source.n_items_, n_items_); // not technically necessary
+    DRACO_DCHECK_EQ(source.dimensionality_, dimensionality_);
+
+    const internal_t *ref = source[source_index];
+    internal_t *const dest = this->operator[](destination_index);
+    std::memcpy(dest, ref, item_size_bytes_);
+  }
+
+  // Copy data directly off of an attribute buffer interleaved into internal
+  // memory.
+  void CopyAttribute(
+      // The dimensionality of the attribute being integrated
+      const internal_t attribute_dimensionality,
+      // The offset in dimensions to insert this attribute.
+      const internal_t offset_dimensionality, const internal_t index,
+      // The direct pointer to the data
+      const void *const attribute_item_data) {
+    // chunk copy
+    const size_t copy_size = sizeof(internal_t) * attribute_dimensionality;
+
+    // a multiply and add can be optimized away with an iterator
+    std::memcpy(data0_ + index * dimensionality_ + offset_dimensionality,
+                attribute_item_data, copy_size);
+  }
+  // Copy data off of a contiguous buffer interleaved into internal memory
+  void CopyAttribute(
+      // The dimensionality of the attribute being integrated
+      const internal_t attribute_dimensionality,
+      // The offset in dimensions to insert this attribute.
+      const internal_t offset_dimensionality,
+      const internal_t *const attribute_mem) {
+    DRACO_DCHECK_LT(offset_dimensionality,
+                    dimensionality_ - attribute_dimensionality);
+    // degenerate case block copy the whole buffer.
+    if (dimensionality_ == attribute_dimensionality) {
+      DRACO_DCHECK_EQ(offset_dimensionality, 0);
+      const size_t copy_size =
+          sizeof(internal_t) * attribute_dimensionality * n_items_;
+      std::memcpy(data0_, attribute_mem, copy_size);
+    } else {  // chunk copy
+      const size_t copy_size = sizeof(internal_t) * attribute_dimensionality;
+      internal_t *internal_data;
+      const internal_t *attribute_data;
+      internal_t item;
+      for (internal_data = data0_ + offset_dimensionality,
+          attribute_data = attribute_mem, item = 0;
+           item < n_items_; internal_data += dimensionality_,
+          attribute_data += attribute_dimensionality, item += 1) {
+        std::memcpy(internal_data, attribute_data, copy_size);
+      }
+    }
+  }
+
+ private:
+  // internal parameters.
+  const uint32_t n_items_;
+  const uint32_t dimensionality_;  // The dimension of the points in the buffer
+  const uint32_t item_size_bytes_;
+  std::vector<internal_t> data_;  // contiguously stored data.  Never resized.
+  internal_t *const data0_;       // raw pointer to base data.
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_POINT_D_VECTOR_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/point_d_vector_test.cc

@@ -0,0 +1,360 @@
+// Copyright 2018 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/point_d_vector.h"
+
+#include "draco/compression/point_cloud/algorithms/point_cloud_types.h"
+#include "draco/core/draco_test_base.h"
+
+namespace draco {
+
+class PointDVectorTest : public ::testing::Test {
+ protected:
+  template <typename PT>
+  void TestIntegrity() {}
+  template <typename PT>
+  void TestSize() {
+    for (uint32_t n_items = 0; n_items <= 10; ++n_items) {
+      for (uint32_t dimensionality = 1; dimensionality <= 10;
+           ++dimensionality) {
+        draco::PointDVector<PT> var(n_items, dimensionality);
+        ASSERT_EQ(n_items, var.size());
+        ASSERT_EQ(n_items * dimensionality, var.GetBufferSize());
+      }
+    }
+  }
+  template <typename PT>
+  void TestContentsContiguous() {
+    for (uint32_t n_items = 1; n_items <= 1000; n_items *= 10) {
+      for (uint32_t dimensionality = 1; dimensionality < 10;
+           dimensionality += 2) {
+        for (uint32_t att_dimensionality = 1;
+             att_dimensionality <= dimensionality; att_dimensionality += 2) {
+          for (uint32_t offset_dimensionality = 0;
+               offset_dimensionality < dimensionality - att_dimensionality;
+               ++offset_dimensionality) {
+            PointDVector<PT> var(n_items, dimensionality);
+
+            std::vector<PT> att(n_items * att_dimensionality);
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                att[val * att_dimensionality + att_dim] = val;
+              }
+            }
+            const PT *const attribute_data = att.data();
+
+            var.CopyAttribute(att_dimensionality, offset_dimensionality,
+                              attribute_data);
+
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                ASSERT_EQ(var[val][offset_dimensionality + att_dim], val);
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  template <typename PT>
+  void TestContentsDiscrete() {
+    for (uint32_t n_items = 1; n_items <= 1000; n_items *= 10) {
+      for (uint32_t dimensionality = 1; dimensionality < 10;
+           dimensionality += 2) {
+        for (uint32_t att_dimensionality = 1;
+             att_dimensionality <= dimensionality; att_dimensionality += 2) {
+          for (uint32_t offset_dimensionality = 0;
+               offset_dimensionality < dimensionality - att_dimensionality;
+               ++offset_dimensionality) {
+            PointDVector<PT> var(n_items, dimensionality);
+
+            std::vector<PT> att(n_items * att_dimensionality);
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                att[val * att_dimensionality + att_dim] = val;
+              }
+            }
+            const PT *const attribute_data = att.data();
+
+            for (PT item = 0; item < n_items; item += 1) {
+              var.CopyAttribute(att_dimensionality, offset_dimensionality, item,
+                                attribute_data + item * att_dimensionality);
+            }
+
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                ASSERT_EQ(var[val][offset_dimensionality + att_dim], val);
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+
+  template <typename PT>
+  void TestContentsCopy() {
+    for (uint32_t n_items = 1; n_items <= 1000; n_items *= 10) {
+      for (uint32_t dimensionality = 1; dimensionality < 10;
+           dimensionality += 2) {
+        for (uint32_t att_dimensionality = 1;
+             att_dimensionality <= dimensionality; att_dimensionality += 2) {
+          for (uint32_t offset_dimensionality = 0;
+               offset_dimensionality < dimensionality - att_dimensionality;
+               ++offset_dimensionality) {
+            PointDVector<PT> var(n_items, dimensionality);
+            PointDVector<PT> dest(n_items, dimensionality);
+
+            std::vector<PT> att(n_items * att_dimensionality);
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                att[val * att_dimensionality + att_dim] = val;
+              }
+            }
+            const PT *const attribute_data = att.data();
+
+            var.CopyAttribute(att_dimensionality, offset_dimensionality,
+                              attribute_data);
+
+            for (PT item = 0; item < n_items; item += 1) {
+              dest.CopyItem(var, item, item);
+            }
+
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                ASSERT_EQ(var[val][offset_dimensionality + att_dim], val);
+                ASSERT_EQ(dest[val][offset_dimensionality + att_dim], val);
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  template <typename PT>
+  void TestIterator() {
+    for (uint32_t n_items = 1; n_items <= 1000; n_items *= 10) {
+      for (uint32_t dimensionality = 1; dimensionality < 10;
+           dimensionality += 2) {
+        for (uint32_t att_dimensionality = 1;
+             att_dimensionality <= dimensionality; att_dimensionality += 2) {
+          for (uint32_t offset_dimensionality = 0;
+               offset_dimensionality < dimensionality - att_dimensionality;
+               ++offset_dimensionality) {
+            PointDVector<PT> var(n_items, dimensionality);
+            PointDVector<PT> dest(n_items, dimensionality);
+
+            std::vector<PT> att(n_items * att_dimensionality);
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                att[val * att_dimensionality + att_dim] = val;
+              }
+            }
+            const PT *const attribute_data = att.data();
+
+            var.CopyAttribute(att_dimensionality, offset_dimensionality,
+                              attribute_data);
+
+            for (PT item = 0; item < n_items; item += 1) {
+              dest.CopyItem(var, item, item);
+            }
+
+            auto V0 = var.begin();
+            auto VE = var.end();
+            auto D0 = dest.begin();
+            auto DE = dest.end();
+
+            while (V0 != VE && D0 != DE) {
+              ASSERT_EQ(*D0, *V0);  // compare PseudoPointD
+              // verify elemental values
+              for (auto index = 0; index < dimensionality; index += 1) {
+                ASSERT_EQ((*D0)[index], (*V0)[index]);
+              }
+              ++V0;
+              ++D0;
+            }
+
+            for (PT val = 0; val < n_items; val += 1) {
+              for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+                ASSERT_EQ(var[val][offset_dimensionality + att_dim], val);
+                ASSERT_EQ(dest[val][offset_dimensionality + att_dim], val);
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  template <typename PT>
+  void TestPoint3Iterator() {
+    for (uint32_t n_items = 1; n_items <= 1000; n_items *= 10) {
+      const uint32_t dimensionality = 3;
+      // for (uint32_t dimensionality = 1; dimensionality < 10;
+      //      dimensionality += 2) {
+      const uint32_t att_dimensionality = 3;
+      // for (uint32_t att_dimensionality = 1;
+      //      att_dimensionality <= dimensionality; att_dimensionality += 2) {
+      for (uint32_t offset_dimensionality = 0;
+           offset_dimensionality < dimensionality - att_dimensionality;
+           ++offset_dimensionality) {
+        PointDVector<PT> var(n_items, dimensionality);
+        PointDVector<PT> dest(n_items, dimensionality);
+
+        std::vector<PT> att(n_items * att_dimensionality);
+        std::vector<draco::Point3ui> att3(n_items);
+        for (PT val = 0; val < n_items; val += 1) {
+          att3[val][0] = val;
+          att3[val][1] = val;
+          att3[val][2] = val;
+          for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+            att[val * att_dimensionality + att_dim] = val;
+          }
+        }
+        const PT *const attribute_data = att.data();
+
+        var.CopyAttribute(att_dimensionality, offset_dimensionality,
+                          attribute_data);
+
+        for (PT item = 0; item < n_items; item += 1) {
+          dest.CopyItem(var, item, item);
+        }
+
+        auto aV0 = att3.begin();
+        auto aVE = att3.end();
+        auto V0 = var.begin();
+        auto VE = var.end();
+        auto D0 = dest.begin();
+        auto DE = dest.end();
+
+        while (aV0 != aVE && V0 != VE && D0 != DE) {
+          ASSERT_EQ(*D0, *V0);  // compare PseudoPointD
+          // verify elemental values
+          for (auto index = 0; index < dimensionality; index += 1) {
+            ASSERT_EQ((*D0)[index], (*V0)[index]);
+            ASSERT_EQ((*D0)[index], (*aV0)[index]);
+            ASSERT_EQ((*aV0)[index], (*V0)[index]);
+          }
+          ++aV0;
+          ++V0;
+          ++D0;
+        }
+
+        for (PT val = 0; val < n_items; val += 1) {
+          for (PT att_dim = 0; att_dim < att_dimensionality; att_dim += 1) {
+            ASSERT_EQ(var[val][offset_dimensionality + att_dim], val);
+            ASSERT_EQ(dest[val][offset_dimensionality + att_dim], val);
+          }
+        }
+      }
+    }
+  }
+
+  void TestPseudoPointDSwap() {
+    draco::Point3ui val = {0, 1, 2};
+    draco::Point3ui dest = {10, 11, 12};
+    draco::PseudoPointD<uint32_t> val_src1(&val[0], 3);
+    draco::PseudoPointD<uint32_t> dest_src1(&dest[0], 3);
+
+    ASSERT_EQ(val_src1[0], 0);
+    ASSERT_EQ(val_src1[1], 1);
+    ASSERT_EQ(val_src1[2], 2);
+    ASSERT_EQ(dest_src1[0], 10);
+    ASSERT_EQ(dest_src1[1], 11);
+    ASSERT_EQ(dest_src1[2], 12);
+
+    ASSERT_NE(val_src1, dest_src1);
+
+    swap(val_src1, dest_src1);
+
+    ASSERT_EQ(dest_src1[0], 0);
+    ASSERT_EQ(dest_src1[1], 1);
+    ASSERT_EQ(dest_src1[2], 2);
+    ASSERT_EQ(val_src1[0], 10);
+    ASSERT_EQ(val_src1[1], 11);
+    ASSERT_EQ(val_src1[2], 12);
+
+    ASSERT_NE(val_src1, dest_src1);
+  }
+  void TestPseudoPointDEquality() {
+    draco::Point3ui val = {0, 1, 2};
+    draco::Point3ui dest = {0, 1, 2};
+    draco::PseudoPointD<uint32_t> val_src1(&val[0], 3);
+    draco::PseudoPointD<uint32_t> val_src2(&val[0], 3);
+    draco::PseudoPointD<uint32_t> dest_src1(&dest[0], 3);
+    draco::PseudoPointD<uint32_t> dest_src2(&dest[0], 3);
+
+    ASSERT_EQ(val_src1, val_src1);
+    ASSERT_EQ(val_src1, val_src2);
+    ASSERT_EQ(dest_src1, val_src1);
+    ASSERT_EQ(dest_src1, val_src2);
+    ASSERT_EQ(val_src2, val_src1);
+    ASSERT_EQ(val_src2, val_src2);
+    ASSERT_EQ(dest_src2, val_src1);
+    ASSERT_EQ(dest_src2, val_src2);
+
+    for (auto i = 0; i < 3; i++) {
+      ASSERT_EQ(val_src1[i], val_src1[i]);
+      ASSERT_EQ(val_src1[i], val_src2[i]);
+      ASSERT_EQ(dest_src1[i], val_src1[i]);
+      ASSERT_EQ(dest_src1[i], val_src2[i]);
+      ASSERT_EQ(val_src2[i], val_src1[i]);
+      ASSERT_EQ(val_src2[i], val_src2[i]);
+      ASSERT_EQ(dest_src2[i], val_src1[i]);
+      ASSERT_EQ(dest_src2[i], val_src2[i]);
+    }
+  }
+  void TestPseudoPointDInequality() {
+    draco::Point3ui val = {0, 1, 2};
+    draco::Point3ui dest = {1, 2, 3};
+    draco::PseudoPointD<uint32_t> val_src1(&val[0], 3);
+    draco::PseudoPointD<uint32_t> val_src2(&val[0], 3);
+    draco::PseudoPointD<uint32_t> dest_src1(&dest[0], 3);
+    draco::PseudoPointD<uint32_t> dest_src2(&dest[0], 3);
+
+    ASSERT_EQ(val_src1, val_src1);
+    ASSERT_EQ(val_src1, val_src2);
+    ASSERT_NE(dest_src1, val_src1);
+    ASSERT_NE(dest_src1, val_src2);
+    ASSERT_EQ(val_src2, val_src1);
+    ASSERT_EQ(val_src2, val_src2);
+    ASSERT_NE(dest_src2, val_src1);
+    ASSERT_NE(dest_src2, val_src2);
+
+    for (auto i = 0; i < 3; i++) {
+      ASSERT_EQ(val_src1[i], val_src1[i]);
+      ASSERT_EQ(val_src1[i], val_src2[i]);
+      ASSERT_NE(dest_src1[i], val_src1[i]);
+      ASSERT_NE(dest_src1[i], val_src2[i]);
+      ASSERT_EQ(val_src2[i], val_src1[i]);
+      ASSERT_EQ(val_src2[i], val_src2[i]);
+      ASSERT_NE(dest_src2[i], val_src1[i]);
+      ASSERT_NE(dest_src2[i], val_src2[i]);
+    }
+  }
+};
+
+TEST_F(PointDVectorTest, VectorTest) {
+  TestSize<uint32_t>();
+  TestContentsDiscrete<uint32_t>();
+  TestContentsContiguous<uint32_t>();
+  TestContentsCopy<uint32_t>();
+  TestIterator<uint32_t>();
+  TestPoint3Iterator<uint32_t>();
+}
+TEST_F(PointDVectorTest, PseudoPointDTest) {
+  TestPseudoPointDSwap();
+  TestPseudoPointDEquality();
+  TestPseudoPointDInequality();
+}
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/points_sequencer.h

@@ -0,0 +1,63 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_POINTS_SEQUENCER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_POINTS_SEQUENCER_H_
+
+#include <vector>
+
+#include "draco/attributes/point_attribute.h"
+
+namespace draco {
+
+// Class for generating a sequence of point ids that can be used to encode
+// or decode attribute values in a specific order.
+// See sequential_attribute_encoders/decoders_controller.h for more details.
+class PointsSequencer {
+ public:
+  PointsSequencer() : out_point_ids_(nullptr) {}
+  virtual ~PointsSequencer() = default;
+
+  // Fills the |out_point_ids| with the generated sequence of point ids.
+  bool GenerateSequence(std::vector<PointIndex> *out_point_ids) {
+    out_point_ids_ = out_point_ids;
+    return GenerateSequenceInternal();
+  }
+
+  // Appends a point to the sequence.
+  void AddPointId(PointIndex point_id) { out_point_ids_->push_back(point_id); }
+
+  // Sets the correct mapping between point ids and value ids. I.e., the inverse
+  // of the |out_point_ids|. In general, |out_point_ids_| does not contain
+  // sufficient information to compute the inverse map, because not all point
+  // ids are necessarily contained within the map.
+  // Must be implemented for sequencers that are used by attribute decoders.
+  virtual bool UpdatePointToAttributeIndexMapping(PointAttribute * /* attr */) {
+    return false;
+  }
+
+ protected:
+  // Method that needs to be implemented by the derived classes. The
+  // implementation is responsible for filling |out_point_ids_| with the valid
+  // sequence of point ids.
+  virtual bool GenerateSequenceInternal() = 0;
+  std::vector<PointIndex> *out_point_ids() const { return out_point_ids_; }
+
+ private:
+  std::vector<PointIndex> *out_point_ids_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_POINTS_SEQUENCER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_decoder.h

@@ -0,0 +1,231 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_DECODER_H_
+
+#include <algorithm>
+#include <cmath>
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_shared.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+#include "draco/compression/bit_coders/rans_bit_decoder.h"
+#include "draco/core/varint_decoding.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Decoder for predictions encoded with the constrained multi-parallelogram
+// encoder. See the corresponding encoder for more details about the prediction
+// method.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeConstrainedMultiParallelogramDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeDecoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+
+  explicit MeshPredictionSchemeConstrainedMultiParallelogramDecoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute),
+        selected_mode_(Mode::OPTIMAL_MULTI_PARALLELOGRAM) {}
+  MeshPredictionSchemeConstrainedMultiParallelogramDecoder(
+      const PointAttribute *attribute, const TransformT &transform,
+      const MeshDataT &mesh_data)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        selected_mode_(Mode::OPTIMAL_MULTI_PARALLELOGRAM) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+
+  bool DecodePredictionData(DecoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+
+ private:
+  typedef constrained_multi_parallelogram::Mode Mode;
+  static constexpr int kMaxNumParallelograms =
+      constrained_multi_parallelogram::kMaxNumParallelograms;
+  // Crease edges are used to store whether any given edge should be used for
+  // parallelogram prediction or not. New values are added in the order in which
+  // the edges are processed. For better compression, the flags are stored in
+  // in separate contexts based on the number of available parallelograms at a
+  // given vertex.
+  std::vector<bool> is_crease_edge_[kMaxNumParallelograms];
+  Mode selected_mode_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeConstrainedMultiParallelogramDecoder<
+    DataTypeT, TransformT, MeshDataT>::
+    ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                          int /* size */, int num_components,
+                          const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(num_components);
+
+  // Predicted values for all simple parallelograms encountered at any given
+  // vertex.
+  std::vector<DataTypeT> pred_vals[kMaxNumParallelograms];
+  for (int i = 0; i < kMaxNumParallelograms; ++i) {
+    pred_vals[i].resize(num_components, 0);
+  }
+  this->transform().ComputeOriginalValue(pred_vals[0].data(), in_corr,
+                                         out_data);
+
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+
+  // Current position in the |is_crease_edge_| array for each context.
+  std::vector<int> is_crease_edge_pos(kMaxNumParallelograms, 0);
+
+  // Used to store predicted value for multi-parallelogram prediction.
+  std::vector<DataTypeT> multi_pred_vals(num_components);
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+  for (int p = 1; p < corner_map_size; ++p) {
+    const CornerIndex start_corner_id =
+        this->mesh_data().data_to_corner_map()->at(p);
+
+    CornerIndex corner_id(start_corner_id);
+    int num_parallelograms = 0;
+    bool first_pass = true;
+    while (corner_id != kInvalidCornerIndex) {
+      if (ComputeParallelogramPrediction(
+              p, corner_id, table, *vertex_to_data_map, out_data,
+              num_components, &(pred_vals[num_parallelograms][0]))) {
+        // Parallelogram prediction applied and stored in
+        // |pred_vals[num_parallelograms]|
+        ++num_parallelograms;
+        // Stop processing when we reach the maximum number of allowed
+        // parallelograms.
+        if (num_parallelograms == kMaxNumParallelograms) {
+          break;
+        }
+      }
+
+      // Proceed to the next corner attached to the vertex. First swing left
+      // and if we reach a boundary, swing right from the start corner.
+      if (first_pass) {
+        corner_id = table->SwingLeft(corner_id);
+      } else {
+        corner_id = table->SwingRight(corner_id);
+      }
+      if (corner_id == start_corner_id) {
+        break;
+      }
+      if (corner_id == kInvalidCornerIndex && first_pass) {
+        first_pass = false;
+        corner_id = table->SwingRight(start_corner_id);
+      }
+    }
+
+    // Check which of the available parallelograms are actually used and compute
+    // the final predicted value.
+    int num_used_parallelograms = 0;
+    if (num_parallelograms > 0) {
+      for (int i = 0; i < num_components; ++i) {
+        multi_pred_vals[i] = 0;
+      }
+      // Check which parallelograms are actually used.
+      for (int i = 0; i < num_parallelograms; ++i) {
+        const int context = num_parallelograms - 1;
+        const int pos = is_crease_edge_pos[context]++;
+        if (is_crease_edge_[context].size() <= pos) {
+          return false;
+        }
+        const bool is_crease = is_crease_edge_[context][pos];
+        if (!is_crease) {
+          ++num_used_parallelograms;
+          for (int j = 0; j < num_components; ++j) {
+            multi_pred_vals[j] += pred_vals[i][j];
+          }
+        }
+      }
+    }
+    const int dst_offset = p * num_components;
+    if (num_used_parallelograms == 0) {
+      // No parallelogram was valid.
+      // We use the last decoded point as a reference.
+      const int src_offset = (p - 1) * num_components;
+      this->transform().ComputeOriginalValue(
+          out_data + src_offset, in_corr + dst_offset, out_data + dst_offset);
+    } else {
+      // Compute the correction from the predicted value.
+      for (int c = 0; c < num_components; ++c) {
+        multi_pred_vals[c] /= num_used_parallelograms;
+      }
+      this->transform().ComputeOriginalValue(
+          multi_pred_vals.data(), in_corr + dst_offset, out_data + dst_offset);
+    }
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeConstrainedMultiParallelogramDecoder<
+    DataTypeT, TransformT, MeshDataT>::DecodePredictionData(DecoderBuffer
+                                                                *buffer) {
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (buffer->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 2)) {
+    // Decode prediction mode.
+    uint8_t mode;
+    if (!buffer->Decode(&mode)) {
+      return false;
+    }
+
+    if (mode != Mode::OPTIMAL_MULTI_PARALLELOGRAM) {
+      // Unsupported mode.
+      return false;
+    }
+  }
+#endif
+
+  // Encode selected edges using separate rans bit coder for each context.
+  for (int i = 0; i < kMaxNumParallelograms; ++i) {
+    uint32_t num_flags;
+    if (!DecodeVarint<uint32_t>(&num_flags, buffer)) {
+      return false;
+    }
+    if (num_flags > 0) {
+      is_crease_edge_[i].resize(num_flags);
+      RAnsBitDecoder decoder;
+      if (!decoder.StartDecoding(buffer)) {
+        return false;
+      }
+      for (uint32_t j = 0; j < num_flags; ++j) {
+        is_crease_edge_[i][j] = decoder.DecodeNextBit();
+      }
+      decoder.EndDecoding();
+    }
+  }
+  return MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                     MeshDataT>::DecodePredictionData(buffer);
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_encoder.h

@@ -0,0 +1,414 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_ENCODER_H_
+
+#include <algorithm>
+#include <cmath>
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_shared.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+#include "draco/compression/bit_coders/rans_bit_encoder.h"
+#include "draco/compression/entropy/shannon_entropy.h"
+#include "draco/core/varint_encoding.h"
+
+namespace draco {
+
+// Compared to standard multi-parallelogram, constrained multi-parallelogram can
+// explicitly select which of the available parallelograms are going to be used
+// for the prediction by marking crease edges between two triangles. This
+// requires storing extra data, but it allows the predictor to avoid using
+// parallelograms that would lead to poor predictions. For improved efficiency,
+// our current implementation limits the maximum number of used parallelograms
+// to four, which covers >95% of the cases (on average, there are only two
+// parallelograms available for any given vertex).
+// All bits of the explicitly chosen configuration are stored together in a
+// single context chosen by the total number of parallelograms available to
+// choose from.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeConstrainedMultiParallelogramEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeEncoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+
+  explicit MeshPredictionSchemeConstrainedMultiParallelogramEncoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute),
+        selected_mode_(Mode::OPTIMAL_MULTI_PARALLELOGRAM) {}
+  MeshPredictionSchemeConstrainedMultiParallelogramEncoder(
+      const PointAttribute *attribute, const TransformT &transform,
+      const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        selected_mode_(Mode::OPTIMAL_MULTI_PARALLELOGRAM) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+
+  bool EncodePredictionData(EncoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+
+ private:
+  // Function used to compute number of bits needed to store overhead of the
+  // predictor. In this case, we consider overhead to be all bits that mark
+  // whether a parallelogram should be used for prediction or not. The input
+  // to this method is the total number of parallelograms that were evaluated so
+  // far(total_parallelogram), and the number of parallelograms we decided to
+  // use for prediction (total_used_parallelograms).
+  // Returns number of bits required to store the overhead.
+  int64_t ComputeOverheadBits(int64_t total_used_parallelograms,
+                              int64_t total_parallelogram) const {
+    // For now we assume RAns coding for the bits where the total required size
+    // is directly correlated to the binary entropy of the input stream.
+    // TODO(ostava): This should be generalized in case we use other binary
+    // coding scheme.
+    const double entropy = ComputeBinaryShannonEntropy(
+        static_cast<uint32_t>(total_parallelogram),
+        static_cast<uint32_t>(total_used_parallelograms));
+
+    // Round up to the nearest full bit.
+    return static_cast<int64_t>(
+        ceil(static_cast<double>(total_parallelogram) * entropy));
+  }
+
+  // Struct that contains data used for measuring the error of each available
+  // parallelogram configuration.
+  struct Error {
+    Error() : num_bits(0), residual_error(0) {}
+
+    // Primary metric: number of bits required to store the data as a result of
+    // the selected prediction configuration.
+    int num_bits;
+    // Secondary metric: absolute difference of residuals for the given
+    // configuration.
+    int residual_error;
+
+    bool operator<(const Error &e) const {
+      if (num_bits < e.num_bits) {
+        return true;
+      }
+      if (num_bits > e.num_bits) {
+        return false;
+      }
+      return residual_error < e.residual_error;
+    }
+  };
+
+  // Computes error for predicting |predicted_val| instead of |actual_val|.
+  // Error is computed as the number of bits needed to encode the difference
+  // between the values.
+  Error ComputeError(const DataTypeT *predicted_val,
+                     const DataTypeT *actual_val, int *out_residuals,
+                     int num_components) {
+    Error error;
+
+    for (int i = 0; i < num_components; ++i) {
+      const int dif = (predicted_val[i] - actual_val[i]);
+      error.residual_error += std::abs(dif);
+      out_residuals[i] = dif;
+      // Entropy needs unsigned symbols, so convert the signed difference to an
+      // unsigned symbol.
+      entropy_symbols_[i] = ConvertSignedIntToSymbol(dif);
+    }
+
+    // Generate entropy data for case that this configuration was used.
+    // Note that the entropy stream is NOT updated in this case.
+    const auto entropy_data =
+        entropy_tracker_.Peek(entropy_symbols_.data(), num_components);
+
+    error.num_bits = entropy_tracker_.GetNumberOfDataBits(entropy_data) +
+                     entropy_tracker_.GetNumberOfRAnsTableBits(entropy_data);
+    return error;
+  }
+
+  typedef constrained_multi_parallelogram::Mode Mode;
+  static constexpr int kMaxNumParallelograms =
+      constrained_multi_parallelogram::kMaxNumParallelograms;
+  // Crease edges are used to store whether any given edge should be used for
+  // parallelogram prediction or not. New values are added in the order in which
+  // the edges are processed. For better compression, the flags are stored in
+  // in separate contexts based on the number of available parallelograms at a
+  // given vertex.
+  // TODO(draco-eng) reconsider std::vector<bool> (performance/space).
+  std::vector<bool> is_crease_edge_[kMaxNumParallelograms];
+  Mode selected_mode_;
+
+  ShannonEntropyTracker entropy_tracker_;
+
+  // Temporary storage for symbols that are fed into the |entropy_stream|.
+  // Always contains only |num_components| entries.
+  std::vector<uint32_t> entropy_symbols_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeConstrainedMultiParallelogramEncoder<
+    DataTypeT, TransformT, MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(in_data, size, num_components);
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+
+  // Predicted values for all simple parallelograms encountered at any given
+  // vertex.
+  std::vector<DataTypeT> pred_vals[kMaxNumParallelograms];
+  for (int i = 0; i < kMaxNumParallelograms; ++i) {
+    pred_vals[i].resize(num_components);
+  }
+  // Used to store predicted value for various multi-parallelogram predictions
+  // (combinations of simple parallelogram predictions).
+  std::vector<DataTypeT> multi_pred_vals(num_components);
+  entropy_symbols_.resize(num_components);
+
+  // Struct for holding data about prediction configuration for different sets
+  // of used parallelograms.
+  struct PredictionConfiguration {
+    PredictionConfiguration()
+        : error(), configuration(0), num_used_parallelograms(0) {}
+    Error error;
+    uint8_t configuration;  // Bitfield, 1 use parallelogram, 0 don't use it.
+    int num_used_parallelograms;
+    std::vector<DataTypeT> predicted_value;
+    std::vector<int32_t> residuals;
+  };
+
+  // Bit-field used for computing permutations of excluded edges
+  // (parallelograms).
+  bool exluded_parallelograms[kMaxNumParallelograms];
+
+  // Data about the number of used parallelogram and total number of available
+  // parallelogram for each context. Used to compute overhead needed for storing
+  // the parallelogram choices made by the encoder.
+  int64_t total_used_parallelograms[kMaxNumParallelograms] = {0};
+  int64_t total_parallelograms[kMaxNumParallelograms] = {0};
+
+  std::vector<int> current_residuals(num_components);
+
+  // We start processing the vertices from the end because this prediction uses
+  // data from previous entries that could be overwritten when an entry is
+  // processed.
+  for (int p =
+           static_cast<int>(this->mesh_data().data_to_corner_map()->size()) - 1;
+       p > 0; --p) {
+    const CornerIndex start_corner_id =
+        this->mesh_data().data_to_corner_map()->at(p);
+
+    // Go over all corners attached to the vertex and compute the predicted
+    // value from the parallelograms defined by their opposite faces.
+    CornerIndex corner_id(start_corner_id);
+    int num_parallelograms = 0;
+    bool first_pass = true;
+    while (corner_id != kInvalidCornerIndex) {
+      if (ComputeParallelogramPrediction(
+              p, corner_id, table, *vertex_to_data_map, in_data, num_components,
+              &(pred_vals[num_parallelograms][0]))) {
+        // Parallelogram prediction applied and stored in
+        // |pred_vals[num_parallelograms]|
+        ++num_parallelograms;
+        // Stop processing when we reach the maximum number of allowed
+        // parallelograms.
+        if (num_parallelograms == kMaxNumParallelograms) {
+          break;
+        }
+      }
+
+      // Proceed to the next corner attached to the vertex. First swing left
+      // and if we reach a boundary, swing right from the start corner.
+      if (first_pass) {
+        corner_id = table->SwingLeft(corner_id);
+      } else {
+        corner_id = table->SwingRight(corner_id);
+      }
+      if (corner_id == start_corner_id) {
+        break;
+      }
+      if (corner_id == kInvalidCornerIndex && first_pass) {
+        first_pass = false;
+        corner_id = table->SwingRight(start_corner_id);
+      }
+    }
+
+    // Offset to the target (destination) vertex.
+    const int dst_offset = p * num_components;
+    Error error;
+
+    // Compute all prediction errors for all possible configurations of
+    // available parallelograms.
+
+    // Variable for holding the best configuration that has been found so far.
+    PredictionConfiguration best_prediction;
+
+    // Compute delta coding error (configuration when no parallelogram is
+    // selected).
+    const int src_offset = (p - 1) * num_components;
+    error = ComputeError(in_data + src_offset, in_data + dst_offset,
+                         &current_residuals[0], num_components);
+
+    if (num_parallelograms > 0) {
+      total_parallelograms[num_parallelograms - 1] += num_parallelograms;
+      const int64_t new_overhead_bits =
+          ComputeOverheadBits(total_used_parallelograms[num_parallelograms - 1],
+                              total_parallelograms[num_parallelograms - 1]);
+      error.num_bits += new_overhead_bits;
+    }
+
+    best_prediction.error = error;
+    best_prediction.configuration = 0;
+    best_prediction.num_used_parallelograms = 0;
+    best_prediction.predicted_value.assign(
+        in_data + src_offset, in_data + src_offset + num_components);
+    best_prediction.residuals.assign(current_residuals.begin(),
+                                     current_residuals.end());
+
+    // Compute prediction error for different cases of used parallelograms.
+    for (int num_used_parallelograms = 1;
+         num_used_parallelograms <= num_parallelograms;
+         ++num_used_parallelograms) {
+      // Mark all parallelograms as excluded.
+      std::fill(exluded_parallelograms,
+                exluded_parallelograms + num_parallelograms, true);
+      // TODO(draco-eng) maybe this should be another std::fill.
+      // Mark the first |num_used_parallelograms| as not excluded.
+      for (int j = 0; j < num_used_parallelograms; ++j) {
+        exluded_parallelograms[j] = false;
+      }
+      // Permute over the excluded edges and compute error for each
+      // configuration (permutation of excluded parallelograms).
+      do {
+        // Reset the multi-parallelogram predicted values.
+        for (int j = 0; j < num_components; ++j) {
+          multi_pred_vals[j] = 0;
+        }
+        uint8_t configuration = 0;
+        for (int j = 0; j < num_parallelograms; ++j) {
+          if (exluded_parallelograms[j]) {
+            continue;
+          }
+          for (int c = 0; c < num_components; ++c) {
+            multi_pred_vals[c] += pred_vals[j][c];
+          }
+          // Set jth bit of the configuration.
+          configuration |= (1 << j);
+        }
+
+        for (int j = 0; j < num_components; ++j) {
+          multi_pred_vals[j] /= num_used_parallelograms;
+        }
+        error = ComputeError(multi_pred_vals.data(), in_data + dst_offset,
+                             &current_residuals[0], num_components);
+        if (num_parallelograms > 0) {
+          const int64_t new_overhead_bits = ComputeOverheadBits(
+              total_used_parallelograms[num_parallelograms - 1] +
+                  num_used_parallelograms,
+              total_parallelograms[num_parallelograms - 1]);
+
+          // Add overhead bits to the total error.
+          error.num_bits += new_overhead_bits;
+        }
+        if (error < best_prediction.error) {
+          best_prediction.error = error;
+          best_prediction.configuration = configuration;
+          best_prediction.num_used_parallelograms = num_used_parallelograms;
+          best_prediction.predicted_value.assign(multi_pred_vals.begin(),
+                                                 multi_pred_vals.end());
+          best_prediction.residuals.assign(current_residuals.begin(),
+                                           current_residuals.end());
+        }
+      } while (std::next_permutation(
+          exluded_parallelograms, exluded_parallelograms + num_parallelograms));
+    }
+    if (num_parallelograms > 0) {
+      total_used_parallelograms[num_parallelograms - 1] +=
+          best_prediction.num_used_parallelograms;
+    }
+
+    // Update the entropy stream by adding selected residuals as symbols to the
+    // stream.
+    for (int i = 0; i < num_components; ++i) {
+      entropy_symbols_[i] =
+          ConvertSignedIntToSymbol(best_prediction.residuals[i]);
+    }
+    entropy_tracker_.Push(entropy_symbols_.data(), num_components);
+
+    for (int i = 0; i < num_parallelograms; ++i) {
+      if ((best_prediction.configuration & (1 << i)) == 0) {
+        // Parallelogram not used, mark the edge as crease.
+        is_crease_edge_[num_parallelograms - 1].push_back(true);
+      } else {
+        // Parallelogram used. Add it to the predicted value and mark the
+        // edge as not a crease.
+        is_crease_edge_[num_parallelograms - 1].push_back(false);
+      }
+    }
+    this->transform().ComputeCorrection(in_data + dst_offset,
+                                        best_prediction.predicted_value.data(),
+                                        out_corr + dst_offset);
+  }
+  // First element is always fixed because it cannot be predicted.
+  for (int i = 0; i < num_components; ++i) {
+    pred_vals[0][i] = static_cast<DataTypeT>(0);
+  }
+  this->transform().ComputeCorrection(in_data, pred_vals[0].data(), out_corr);
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeConstrainedMultiParallelogramEncoder<
+    DataTypeT, TransformT, MeshDataT>::EncodePredictionData(EncoderBuffer
+                                                                *buffer) {
+  // Encode selected edges using separate rans bit coder for each context.
+  for (int i = 0; i < kMaxNumParallelograms; ++i) {
+    // |i| is the context based on the number of available parallelograms, which
+    // is always equal to |i + 1|.
+    const int num_used_parallelograms = i + 1;
+    EncodeVarint<uint32_t>(is_crease_edge_[i].size(), buffer);
+    if (is_crease_edge_[i].size()) {
+      RAnsBitEncoder encoder;
+      encoder.StartEncoding();
+      // Encode the crease edge flags in the reverse vertex order that is needed
+      // be the decoder. Note that for the currently supported mode, each vertex
+      // has exactly |num_used_parallelograms| edges that need to be encoded.
+      for (int j = static_cast<int>(is_crease_edge_[i].size()) -
+                   num_used_parallelograms;
+           j >= 0; j -= num_used_parallelograms) {
+        // Go over all edges of the current vertex.
+        for (int k = 0; k < num_used_parallelograms; ++k) {
+          encoder.EncodeBit(is_crease_edge_[i][j + k]);
+        }
+      }
+      encoder.EndEncoding(buffer);
+    }
+  }
+  return MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                     MeshDataT>::EncodePredictionData(buffer);
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_shared.h

@@ -0,0 +1,34 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_SHARED_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_SHARED_H_
+
+namespace draco {
+
+// Data shared between constrained multi-parallelogram encoder and decoder.
+namespace constrained_multi_parallelogram {
+
+enum Mode {
+  // Selects the optimal multi-parallelogram from up to 4 available
+  // parallelograms.
+  OPTIMAL_MULTI_PARALLELOGRAM = 0,
+};
+
+static constexpr int kMaxNumParallelograms = 4;
+
+}  // namespace constrained_multi_parallelogram
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_CONSTRAINED_MULTI_PARALLELOGRAM_SHARED_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_data.h

@@ -0,0 +1,72 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DATA_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DATA_H_
+
+#include "draco/mesh/corner_table.h"
+#include "draco/mesh/mesh.h"
+
+namespace draco {
+
+// Class stores data about the connectivity data of the mesh and information
+// about how the connectivity was encoded/decoded.
+template <class CornerTableT>
+class MeshPredictionSchemeData {
+ public:
+  typedef CornerTableT CornerTable;
+  MeshPredictionSchemeData()
+      : mesh_(nullptr),
+        corner_table_(nullptr),
+        vertex_to_data_map_(nullptr),
+        data_to_corner_map_(nullptr) {}
+
+  void Set(const Mesh *mesh, const CornerTable *table,
+           const std::vector<CornerIndex> *data_to_corner_map,
+           const std::vector<int32_t> *vertex_to_data_map) {
+    mesh_ = mesh;
+    corner_table_ = table;
+    data_to_corner_map_ = data_to_corner_map;
+    vertex_to_data_map_ = vertex_to_data_map;
+  }
+
+  const Mesh *mesh() const { return mesh_; }
+  const CornerTable *corner_table() const { return corner_table_; }
+  const std::vector<int32_t> *vertex_to_data_map() const {
+    return vertex_to_data_map_;
+  }
+  const std::vector<CornerIndex> *data_to_corner_map() const {
+    return data_to_corner_map_;
+  }
+  bool IsInitialized() const {
+    return mesh_ != nullptr && corner_table_ != nullptr &&
+           vertex_to_data_map_ != nullptr && data_to_corner_map_ != nullptr;
+  }
+
+ private:
+  const Mesh *mesh_;
+  const CornerTable *corner_table_;
+
+  // Mapping between vertices and their encoding order. I.e. when an attribute
+  // entry on a given vertex was encoded.
+  const std::vector<int32_t> *vertex_to_data_map_;
+
+  // Array that stores which corner was processed when a given attribute entry
+  // was encoded or decoded.
+  const std::vector<CornerIndex> *data_to_corner_map_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DATA_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h

@@ -0,0 +1,46 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_data.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder.h"
+
+namespace draco {
+
+// Base class for all mesh prediction scheme decoders that use the mesh
+// connectivity data. |MeshDataT| can be any class that provides the same
+// interface as the PredictionSchemeMeshData class.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeDecoder
+    : public PredictionSchemeDecoder<DataTypeT, TransformT> {
+ public:
+  typedef MeshDataT MeshData;
+  MeshPredictionSchemeDecoder(const PointAttribute *attribute,
+                              const TransformT &transform,
+                              const MeshDataT &mesh_data)
+      : PredictionSchemeDecoder<DataTypeT, TransformT>(attribute, transform),
+        mesh_data_(mesh_data) {}
+
+ protected:
+  const MeshData &mesh_data() const { return mesh_data_; }
+
+ private:
+  MeshData mesh_data_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h

@@ -0,0 +1,46 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_data.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder.h"
+
+namespace draco {
+
+// Base class for all mesh prediction scheme encoders that use the mesh
+// connectivity data. |MeshDataT| can be any class that provides the same
+// interface as the PredictionSchemeMeshData class.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeEncoder
+    : public PredictionSchemeEncoder<DataTypeT, TransformT> {
+ public:
+  typedef MeshDataT MeshData;
+  MeshPredictionSchemeEncoder(const PointAttribute *attribute,
+                              const TransformT &transform,
+                              const MeshDataT &mesh_data)
+      : PredictionSchemeEncoder<DataTypeT, TransformT>(attribute, transform),
+        mesh_data_(mesh_data) {}
+
+ protected:
+  const MeshData &mesh_data() const { return mesh_data_; }
+
+ private:
+  MeshData mesh_data_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_decoder.h

@@ -0,0 +1,172 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_predictor_area.h"
+#include "draco/compression/bit_coders/rans_bit_decoder.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// See MeshPredictionSchemeGeometricNormalEncoder for documentation.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeGeometricNormalDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeGeometricNormalDecoder(const PointAttribute *attribute,
+                                             const TransformT &transform,
+                                             const MeshDataT &mesh_data)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        predictor_(mesh_data) {}
+
+ private:
+  MeshPredictionSchemeGeometricNormalDecoder() {}
+
+ public:
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+
+  bool DecodePredictionData(DecoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_GEOMETRIC_NORMAL;
+  }
+
+  bool IsInitialized() const override {
+    if (!predictor_.IsInitialized()) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    if (!octahedron_tool_box_.IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    predictor_.SetPositionAttribute(*att);
+    return true;
+  }
+  void SetQuantizationBits(int q) {
+    octahedron_tool_box_.SetQuantizationBits(q);
+  }
+
+ private:
+  MeshPredictionSchemeGeometricNormalPredictorArea<DataTypeT, TransformT,
+                                                   MeshDataT>
+      predictor_;
+  OctahedronToolBox octahedron_tool_box_;
+  RAnsBitDecoder flip_normal_bit_decoder_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeGeometricNormalDecoder<
+    DataTypeT, TransformT,
+    MeshDataT>::ComputeOriginalValues(const CorrType *in_corr,
+                                      DataTypeT *out_data, int /* size */,
+                                      int num_components,
+                                      const PointIndex *entry_to_point_id_map) {
+  this->SetQuantizationBits(this->transform().quantization_bits());
+  predictor_.SetEntryToPointIdMap(entry_to_point_id_map);
+  DRACO_DCHECK(this->IsInitialized());
+
+  // Expecting in_data in octahedral coordinates, i.e., portable attribute.
+  DRACO_DCHECK_EQ(num_components, 2);
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+
+  VectorD<int32_t, 3> pred_normal_3d;
+  int32_t pred_normal_oct[2];
+
+  for (int data_id = 0; data_id < corner_map_size; ++data_id) {
+    const CornerIndex corner_id =
+        this->mesh_data().data_to_corner_map()->at(data_id);
+    predictor_.ComputePredictedValue(corner_id, pred_normal_3d.data());
+
+    // Compute predicted octahedral coordinates.
+    octahedron_tool_box_.CanonicalizeIntegerVector(pred_normal_3d.data());
+    DRACO_DCHECK_EQ(pred_normal_3d.AbsSum(),
+                    octahedron_tool_box_.center_value());
+    if (flip_normal_bit_decoder_.DecodeNextBit()) {
+      pred_normal_3d = -pred_normal_3d;
+    }
+    octahedron_tool_box_.IntegerVectorToQuantizedOctahedralCoords(
+        pred_normal_3d.data(), pred_normal_oct, pred_normal_oct + 1);
+
+    const int data_offset = data_id * 2;
+    this->transform().ComputeOriginalValue(
+        pred_normal_oct, in_corr + data_offset, out_data + data_offset);
+  }
+  flip_normal_bit_decoder_.EndDecoding();
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeGeometricNormalDecoder<
+    DataTypeT, TransformT, MeshDataT>::DecodePredictionData(DecoderBuffer
+                                                                *buffer) {
+  // Get data needed for transform
+  if (!this->transform().DecodeTransformData(buffer)) {
+    return false;
+  }
+
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (buffer->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 2)) {
+    uint8_t prediction_mode;
+    if (!buffer->Decode(&prediction_mode)) {
+      return false;
+    }
+
+    if (!predictor_.SetNormalPredictionMode(
+            NormalPredictionMode(prediction_mode))) {
+      return false;
+    }
+  }
+#endif
+
+  // Init normal flips.
+  if (!flip_normal_bit_decoder_.StartDecoding(buffer)) {
+    return false;
+  }
+
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_encoder.h

@@ -0,0 +1,180 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_predictor_area.h"
+#include "draco/compression/bit_coders/rans_bit_encoder.h"
+#include "draco/compression/config/compression_shared.h"
+
+namespace draco {
+
+// Prediction scheme for normals based on the underlying geometry.
+// At a smooth vertices normals are computed by weighting the normals of
+// adjacent faces with the area of these faces. At seams, the same approach
+// applies for seam corners.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeGeometricNormalEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeGeometricNormalEncoder(const PointAttribute *attribute,
+                                             const TransformT &transform,
+                                             const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        predictor_(mesh_data) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+
+  bool EncodePredictionData(EncoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_GEOMETRIC_NORMAL;
+  }
+
+  bool IsInitialized() const override {
+    if (!predictor_.IsInitialized()) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    predictor_.SetPositionAttribute(*att);
+    return true;
+  }
+
+ private:
+  void SetQuantizationBits(int q) {
+    DRACO_DCHECK_GE(q, 2);
+    DRACO_DCHECK_LE(q, 30);
+    octahedron_tool_box_.SetQuantizationBits(q);
+  }
+  MeshPredictionSchemeGeometricNormalPredictorArea<DataTypeT, TransformT,
+                                                   MeshDataT>
+      predictor_;
+
+  OctahedronToolBox octahedron_tool_box_;
+  RAnsBitEncoder flip_normal_bit_encoder_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeGeometricNormalEncoder<DataTypeT, TransformT,
+                                                MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex *entry_to_point_id_map) {
+  this->SetQuantizationBits(this->transform().quantization_bits());
+  predictor_.SetEntryToPointIdMap(entry_to_point_id_map);
+  DRACO_DCHECK(this->IsInitialized());
+  // Expecting in_data in octahedral coordinates, i.e., portable attribute.
+  DRACO_DCHECK_EQ(num_components, 2);
+
+  flip_normal_bit_encoder_.StartEncoding();
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+
+  VectorD<int32_t, 3> pred_normal_3d;
+  VectorD<int32_t, 2> pos_pred_normal_oct;
+  VectorD<int32_t, 2> neg_pred_normal_oct;
+  VectorD<int32_t, 2> pos_correction;
+  VectorD<int32_t, 2> neg_correction;
+  for (int data_id = 0; data_id < corner_map_size; ++data_id) {
+    const CornerIndex corner_id =
+        this->mesh_data().data_to_corner_map()->at(data_id);
+    predictor_.ComputePredictedValue(corner_id, pred_normal_3d.data());
+
+    // Compute predicted octahedral coordinates.
+    octahedron_tool_box_.CanonicalizeIntegerVector(pred_normal_3d.data());
+    DRACO_DCHECK_EQ(pred_normal_3d.AbsSum(),
+                    octahedron_tool_box_.center_value());
+
+    // Compute octahedral coordinates for both possible directions.
+    octahedron_tool_box_.IntegerVectorToQuantizedOctahedralCoords(
+        pred_normal_3d.data(), pos_pred_normal_oct.data(),
+        pos_pred_normal_oct.data() + 1);
+    pred_normal_3d = -pred_normal_3d;
+    octahedron_tool_box_.IntegerVectorToQuantizedOctahedralCoords(
+        pred_normal_3d.data(), neg_pred_normal_oct.data(),
+        neg_pred_normal_oct.data() + 1);
+
+    // Choose the one with the best correction value.
+    const int data_offset = data_id * 2;
+    this->transform().ComputeCorrection(in_data + data_offset,
+                                        pos_pred_normal_oct.data(),
+                                        pos_correction.data());
+    this->transform().ComputeCorrection(in_data + data_offset,
+                                        neg_pred_normal_oct.data(),
+                                        neg_correction.data());
+    pos_correction[0] = octahedron_tool_box_.ModMax(pos_correction[0]);
+    pos_correction[1] = octahedron_tool_box_.ModMax(pos_correction[1]);
+    neg_correction[0] = octahedron_tool_box_.ModMax(neg_correction[0]);
+    neg_correction[1] = octahedron_tool_box_.ModMax(neg_correction[1]);
+    if (pos_correction.AbsSum() < neg_correction.AbsSum()) {
+      flip_normal_bit_encoder_.EncodeBit(false);
+      (out_corr + data_offset)[0] =
+          octahedron_tool_box_.MakePositive(pos_correction[0]);
+      (out_corr + data_offset)[1] =
+          octahedron_tool_box_.MakePositive(pos_correction[1]);
+    } else {
+      flip_normal_bit_encoder_.EncodeBit(true);
+      (out_corr + data_offset)[0] =
+          octahedron_tool_box_.MakePositive(neg_correction[0]);
+      (out_corr + data_offset)[1] =
+          octahedron_tool_box_.MakePositive(neg_correction[1]);
+    }
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeGeometricNormalEncoder<
+    DataTypeT, TransformT, MeshDataT>::EncodePredictionData(EncoderBuffer
+                                                                *buffer) {
+  if (!this->transform().EncodeTransformData(buffer)) {
+    return false;
+  }
+
+  // Encode normal flips.
+  flip_normal_bit_encoder_.EndEncoding(buffer);
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_predictor_area.h

@@ -0,0 +1,117 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_AREA_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_AREA_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_predictor_base.h"
+
+namespace draco {
+
+// This predictor estimates the normal via the surrounding triangles of the
+// given corner. Triangles are weighted according to their area.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeGeometricNormalPredictorArea
+    : public MeshPredictionSchemeGeometricNormalPredictorBase<
+          DataTypeT, TransformT, MeshDataT> {
+  typedef MeshPredictionSchemeGeometricNormalPredictorBase<
+      DataTypeT, TransformT, MeshDataT>
+      Base;
+
+ public:
+  explicit MeshPredictionSchemeGeometricNormalPredictorArea(const MeshDataT &md)
+      : Base(md) {
+    this->SetNormalPredictionMode(TRIANGLE_AREA);
+  };
+  virtual ~MeshPredictionSchemeGeometricNormalPredictorArea() {}
+
+  // Computes predicted octahedral coordinates on a given corner.
+  void ComputePredictedValue(CornerIndex corner_id,
+                             DataTypeT *prediction) override {
+    DRACO_DCHECK(this->IsInitialized());
+    typedef typename MeshDataT::CornerTable CornerTable;
+    const CornerTable *const corner_table = this->mesh_data_.corner_table();
+    // Going to compute the predicted normal from the surrounding triangles
+    // according to the connectivity of the given corner table.
+    VertexCornersIterator<CornerTable> cit(corner_table, corner_id);
+    // Position of central vertex does not change in loop.
+    const VectorD<int64_t, 3> pos_cent = this->GetPositionForCorner(corner_id);
+    // Computing normals for triangles and adding them up.
+
+    VectorD<int64_t, 3> normal;
+    CornerIndex c_next, c_prev;
+    while (!cit.End()) {
+      // Getting corners.
+      if (this->normal_prediction_mode_ == ONE_TRIANGLE) {
+        c_next = corner_table->Next(corner_id);
+        c_prev = corner_table->Previous(corner_id);
+      } else {
+        c_next = corner_table->Next(cit.Corner());
+        c_prev = corner_table->Previous(cit.Corner());
+      }
+      const VectorD<int64_t, 3> pos_next = this->GetPositionForCorner(c_next);
+      const VectorD<int64_t, 3> pos_prev = this->GetPositionForCorner(c_prev);
+
+      // Computing delta vectors to next and prev.
+      const VectorD<int64_t, 3> delta_next = pos_next - pos_cent;
+      const VectorD<int64_t, 3> delta_prev = pos_prev - pos_cent;
+
+      // Computing cross product.
+      const VectorD<int64_t, 3> cross = CrossProduct(delta_next, delta_prev);
+
+      // Prevent signed integer overflows by doing math as unsigned.
+      auto normal_data = reinterpret_cast<uint64_t *>(normal.data());
+      auto cross_data = reinterpret_cast<const uint64_t *>(cross.data());
+      normal_data[0] = normal_data[0] + cross_data[0];
+      normal_data[1] = normal_data[1] + cross_data[1];
+      normal_data[2] = normal_data[2] + cross_data[2];
+
+      cit.Next();
+    }
+
+    // Convert to int32_t, make sure entries are not too large.
+    constexpr int64_t upper_bound = 1 << 29;
+    if (this->normal_prediction_mode_ == ONE_TRIANGLE) {
+      const int32_t abs_sum = static_cast<int32_t>(normal.AbsSum());
+      if (abs_sum > upper_bound) {
+        const int64_t quotient = abs_sum / upper_bound;
+        normal = normal / quotient;
+      }
+    } else {
+      const int64_t abs_sum = normal.AbsSum();
+      if (abs_sum > upper_bound) {
+        const int64_t quotient = abs_sum / upper_bound;
+        normal = normal / quotient;
+      }
+    }
+    DRACO_DCHECK_LE(normal.AbsSum(), upper_bound);
+    prediction[0] = static_cast<int32_t>(normal[0]);
+    prediction[1] = static_cast<int32_t>(normal[1]);
+    prediction[2] = static_cast<int32_t>(normal[2]);
+  }
+  bool SetNormalPredictionMode(NormalPredictionMode mode) override {
+    if (mode == ONE_TRIANGLE) {
+      this->normal_prediction_mode_ = mode;
+      return true;
+    } else if (mode == TRIANGLE_AREA) {
+      this->normal_prediction_mode_ = mode;
+      return true;
+    }
+    return false;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_AREA_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_predictor_base.h

@@ -0,0 +1,96 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_BASE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_BASE_H_
+
+#include <math.h>
+
+#include "draco/attributes/point_attribute.h"
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/math_utils.h"
+#include "draco/core/vector_d.h"
+#include "draco/mesh/corner_table.h"
+#include "draco/mesh/corner_table_iterators.h"
+
+namespace draco {
+
+// Base class for geometric normal predictors using position attribute.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeGeometricNormalPredictorBase {
+ protected:
+  explicit MeshPredictionSchemeGeometricNormalPredictorBase(const MeshDataT &md)
+      : pos_attribute_(nullptr),
+        entry_to_point_id_map_(nullptr),
+        mesh_data_(md) {}
+  virtual ~MeshPredictionSchemeGeometricNormalPredictorBase() {}
+
+ public:
+  void SetPositionAttribute(const PointAttribute &position_attribute) {
+    pos_attribute_ = &position_attribute;
+  }
+  void SetEntryToPointIdMap(const PointIndex *map) {
+    entry_to_point_id_map_ = map;
+  }
+  bool IsInitialized() const {
+    if (pos_attribute_ == nullptr) {
+      return false;
+    }
+    if (entry_to_point_id_map_ == nullptr) {
+      return false;
+    }
+    return true;
+  }
+
+  virtual bool SetNormalPredictionMode(NormalPredictionMode mode) = 0;
+  virtual NormalPredictionMode GetNormalPredictionMode() const {
+    return normal_prediction_mode_;
+  }
+
+ protected:
+  VectorD<int64_t, 3> GetPositionForDataId(int data_id) const {
+    DRACO_DCHECK(this->IsInitialized());
+    const auto point_id = entry_to_point_id_map_[data_id];
+    const auto pos_val_id = pos_attribute_->mapped_index(point_id);
+    VectorD<int64_t, 3> pos;
+    pos_attribute_->ConvertValue(pos_val_id, &pos[0]);
+    return pos;
+  }
+  VectorD<int64_t, 3> GetPositionForCorner(CornerIndex ci) const {
+    DRACO_DCHECK(this->IsInitialized());
+    const auto corner_table = mesh_data_.corner_table();
+    const auto vert_id = corner_table->Vertex(ci).value();
+    const auto data_id = mesh_data_.vertex_to_data_map()->at(vert_id);
+    return GetPositionForDataId(data_id);
+  }
+  VectorD<int32_t, 2> GetOctahedralCoordForDataId(int data_id,
+                                                  const DataTypeT *data) const {
+    DRACO_DCHECK(this->IsInitialized());
+    const int data_offset = data_id * 2;
+    return VectorD<int32_t, 2>(data[data_offset], data[data_offset + 1]);
+  }
+  // Computes predicted octahedral coordinates on a given corner.
+  virtual void ComputePredictedValue(CornerIndex corner_id,
+                                     DataTypeT *prediction) = 0;
+
+  const PointAttribute *pos_attribute_;
+  const PointIndex *entry_to_point_id_map_;
+  MeshDataT mesh_data_;
+  NormalPredictionMode normal_prediction_mode_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_GEOMETRIC_NORMAL_PREDICTOR_BASE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_multi_parallelogram_decoder.h

@@ -0,0 +1,126 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Decoder for predictions encoded by multi-parallelogram encoding scheme.
+// See the corresponding encoder for method description.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeMultiParallelogramDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeDecoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+
+  explicit MeshPredictionSchemeMultiParallelogramDecoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute) {}
+  MeshPredictionSchemeMultiParallelogramDecoder(const PointAttribute *attribute,
+                                                const TransformT &transform,
+                                                const MeshDataT &mesh_data)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_MULTI_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeMultiParallelogramDecoder<DataTypeT, TransformT,
+                                                   MeshDataT>::
+    ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                          int /* size */, int num_components,
+                          const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(num_components);
+
+  // For storage of prediction values (already initialized to zero).
+  std::unique_ptr<DataTypeT[]> pred_vals(new DataTypeT[num_components]());
+  std::unique_ptr<DataTypeT[]> parallelogram_pred_vals(
+      new DataTypeT[num_components]());
+
+  this->transform().ComputeOriginalValue(pred_vals.get(), in_corr, out_data);
+
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+  for (int p = 1; p < corner_map_size; ++p) {
+    const CornerIndex start_corner_id =
+        this->mesh_data().data_to_corner_map()->at(p);
+
+    CornerIndex corner_id(start_corner_id);
+    int num_parallelograms = 0;
+    for (int i = 0; i < num_components; ++i) {
+      pred_vals[i] = static_cast<DataTypeT>(0);
+    }
+    while (corner_id != kInvalidCornerIndex) {
+      if (ComputeParallelogramPrediction(
+              p, corner_id, table, *vertex_to_data_map, out_data,
+              num_components, parallelogram_pred_vals.get())) {
+        for (int c = 0; c < num_components; ++c) {
+          pred_vals[c] += parallelogram_pred_vals[c];
+        }
+        ++num_parallelograms;
+      }
+
+      // Proceed to the next corner attached to the vertex.
+      corner_id = table->SwingRight(corner_id);
+      if (corner_id == start_corner_id) {
+        corner_id = kInvalidCornerIndex;
+      }
+    }
+
+    const int dst_offset = p * num_components;
+    if (num_parallelograms == 0) {
+      // No parallelogram was valid.
+      // We use the last decoded point as a reference.
+      const int src_offset = (p - 1) * num_components;
+      this->transform().ComputeOriginalValue(
+          out_data + src_offset, in_corr + dst_offset, out_data + dst_offset);
+    } else {
+      // Compute the correction from the predicted value.
+      for (int c = 0; c < num_components; ++c) {
+        pred_vals[c] /= num_parallelograms;
+      }
+      this->transform().ComputeOriginalValue(
+          pred_vals.get(), in_corr + dst_offset, out_data + dst_offset);
+    }
+  }
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_DECODER_H_
+#endif

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_multi_parallelogram_encoder.h

@@ -0,0 +1,133 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+
+namespace draco {
+
+// Multi parallelogram prediction predicts attribute values using information
+// from all opposite faces to the predicted vertex, compared to the standard
+// prediction scheme, where only one opposite face is used (see
+// prediction_scheme_parallelogram.h). This approach is generally slower than
+// the standard parallelogram prediction, but it usually results in better
+// prediction (5 - 20% based on the quantization level. Better gains can be
+// achieved when more aggressive quantization is used).
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeMultiParallelogramEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeEncoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+
+  explicit MeshPredictionSchemeMultiParallelogramEncoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute) {}
+  MeshPredictionSchemeMultiParallelogramEncoder(const PointAttribute *attribute,
+                                                const TransformT &transform,
+                                                const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_MULTI_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeMultiParallelogramEncoder<DataTypeT, TransformT,
+                                                   MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(in_data, size, num_components);
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+
+  // For storage of prediction values (already initialized to zero).
+  std::unique_ptr<DataTypeT[]> pred_vals(new DataTypeT[num_components]());
+  std::unique_ptr<DataTypeT[]> parallelogram_pred_vals(
+      new DataTypeT[num_components]());
+
+  // We start processing from the end because this prediction uses data from
+  // previous entries that could be overwritten when an entry is processed.
+  for (int p =
+           static_cast<int>(this->mesh_data().data_to_corner_map()->size() - 1);
+       p > 0; --p) {
+    const CornerIndex start_corner_id =
+        this->mesh_data().data_to_corner_map()->at(p);
+
+    // Go over all corners attached to the vertex and compute the predicted
+    // value from the parallelograms defined by their opposite faces.
+    CornerIndex corner_id(start_corner_id);
+    int num_parallelograms = 0;
+    for (int i = 0; i < num_components; ++i) {
+      pred_vals[i] = static_cast<DataTypeT>(0);
+    }
+    while (corner_id != kInvalidCornerIndex) {
+      if (ComputeParallelogramPrediction(
+              p, corner_id, table, *vertex_to_data_map, in_data, num_components,
+              parallelogram_pred_vals.get())) {
+        for (int c = 0; c < num_components; ++c) {
+          pred_vals[c] += parallelogram_pred_vals[c];
+        }
+        ++num_parallelograms;
+      }
+
+      // Proceed to the next corner attached to the vertex.
+      corner_id = table->SwingRight(corner_id);
+      if (corner_id == start_corner_id) {
+        corner_id = kInvalidCornerIndex;
+      }
+    }
+    const int dst_offset = p * num_components;
+    if (num_parallelograms == 0) {
+      // No parallelogram was valid.
+      // We use the last encoded point as a reference.
+      const int src_offset = (p - 1) * num_components;
+      this->transform().ComputeCorrection(
+          in_data + dst_offset, in_data + src_offset, out_corr + dst_offset);
+    } else {
+      // Compute the correction from the predicted value.
+      for (int c = 0; c < num_components; ++c) {
+        pred_vals[c] /= num_parallelograms;
+      }
+      this->transform().ComputeCorrection(in_data + dst_offset, pred_vals.get(),
+                                          out_corr + dst_offset);
+    }
+  }
+  // First element is always fixed because it cannot be predicted.
+  for (int i = 0; i < num_components; ++i) {
+    pred_vals[i] = static_cast<DataTypeT>(0);
+  }
+  this->transform().ComputeCorrection(in_data, pred_vals.get(), out_corr);
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_MULTI_PARALLELOGRAM_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_decoder.h

@@ -0,0 +1,98 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+
+namespace draco {
+
+// Decoder for attribute values encoded with the standard parallelogram
+// prediction. See the description of the corresponding encoder for more
+// details.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeParallelogramDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeDecoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+  explicit MeshPredictionSchemeParallelogramDecoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute) {}
+  MeshPredictionSchemeParallelogramDecoder(const PointAttribute *attribute,
+                                           const TransformT &transform,
+                                           const MeshDataT &mesh_data)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeParallelogramDecoder<DataTypeT, TransformT,
+                                              MeshDataT>::
+    ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                          int /* size */, int num_components,
+                          const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(num_components);
+
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+
+  // For storage of prediction values (already initialized to zero).
+  std::unique_ptr<DataTypeT[]> pred_vals(new DataTypeT[num_components]());
+
+  // Restore the first value.
+  this->transform().ComputeOriginalValue(pred_vals.get(), in_corr, out_data);
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+  for (int p = 1; p < corner_map_size; ++p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    const int dst_offset = p * num_components;
+    if (!ComputeParallelogramPrediction(p, corner_id, table,
+                                        *vertex_to_data_map, out_data,
+                                        num_components, pred_vals.get())) {
+      // Parallelogram could not be computed, Possible because some of the
+      // vertices are not valid (not encoded yet).
+      // We use the last encoded point as a reference (delta coding).
+      const int src_offset = (p - 1) * num_components;
+      this->transform().ComputeOriginalValue(
+          out_data + src_offset, in_corr + dst_offset, out_data + dst_offset);
+    } else {
+      // Apply the parallelogram prediction.
+      this->transform().ComputeOriginalValue(
+          pred_vals.get(), in_corr + dst_offset, out_data + dst_offset);
+    }
+  }
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_encoder.h

@@ -0,0 +1,111 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h"
+
+namespace draco {
+
+// Parallelogram prediction predicts an attribute value V from three vertices
+// on the opposite face to the predicted vertex. The values on the three
+// vertices are used to construct a parallelogram V' = O - A - B, where O is the
+// value on the opposite vertex, and A, B are values on the shared vertices:
+//     V
+//    / \
+//   /   \
+//  /     \
+// A-------B
+//  \     /
+//   \   /
+//    \ /
+//     O
+//
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeParallelogramEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeEncoder<DataTypeT, TransformT>::CorrType;
+  using CornerTable = typename MeshDataT::CornerTable;
+  explicit MeshPredictionSchemeParallelogramEncoder(
+      const PointAttribute *attribute)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute) {}
+  MeshPredictionSchemeParallelogramEncoder(const PointAttribute *attribute,
+                                           const TransformT &transform,
+                                           const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_PARALLELOGRAM;
+  }
+
+  bool IsInitialized() const override {
+    return this->mesh_data().IsInitialized();
+  }
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeParallelogramEncoder<DataTypeT, TransformT,
+                                              MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex * /* entry_to_point_id_map */) {
+  this->transform().Init(in_data, size, num_components);
+  // For storage of prediction values (already initialized to zero).
+  std::unique_ptr<DataTypeT[]> pred_vals(new DataTypeT[num_components]());
+
+  // We start processing from the end because this prediction uses data from
+  // previous entries that could be overwritten when an entry is processed.
+  const CornerTable *const table = this->mesh_data().corner_table();
+  const std::vector<int32_t> *const vertex_to_data_map =
+      this->mesh_data().vertex_to_data_map();
+  for (int p =
+           static_cast<int>(this->mesh_data().data_to_corner_map()->size() - 1);
+       p > 0; --p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    const int dst_offset = p * num_components;
+    if (!ComputeParallelogramPrediction(p, corner_id, table,
+                                        *vertex_to_data_map, in_data,
+                                        num_components, pred_vals.get())) {
+      // Parallelogram could not be computed, Possible because some of the
+      // vertices are not valid (not encoded yet).
+      // We use the last encoded point as a reference (delta coding).
+      const int src_offset = (p - 1) * num_components;
+      this->transform().ComputeCorrection(
+          in_data + dst_offset, in_data + src_offset, out_corr + dst_offset);
+    } else {
+      // Apply the parallelogram prediction.
+      this->transform().ComputeCorrection(in_data + dst_offset, pred_vals.get(),
+                                          out_corr + dst_offset);
+    }
+  }
+  // First element is always fixed because it cannot be predicted.
+  for (int i = 0; i < num_components; ++i) {
+    pred_vals[i] = static_cast<DataTypeT>(0);
+  }
+  this->transform().ComputeCorrection(in_data, pred_vals.get(), out_corr);
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_shared.h

@@ -0,0 +1,78 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Shared functionality for different parallelogram prediction schemes.
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_SHARED_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_SHARED_H_
+
+#include "draco/mesh/corner_table.h"
+#include "draco/mesh/mesh.h"
+
+namespace draco {
+
+// TODO(draco-eng) consolidate Vertex/next/previous queries to one call
+// (performance).
+template <class CornerTableT>
+inline void GetParallelogramEntries(
+    const CornerIndex ci, const CornerTableT *table,
+    const std::vector<int32_t> &vertex_to_data_map, int *opp_entry,
+    int *next_entry, int *prev_entry) {
+  // One vertex of the input |table| correspond to exactly one attribute value
+  // entry. The |table| can be either CornerTable for per-vertex attributes,
+  // or MeshAttributeCornerTable for attributes with interior seams.
+  *opp_entry = vertex_to_data_map[table->Vertex(ci).value()];
+  *next_entry = vertex_to_data_map[table->Vertex(table->Next(ci)).value()];
+  *prev_entry = vertex_to_data_map[table->Vertex(table->Previous(ci)).value()];
+}
+
+// Computes parallelogram prediction for a given corner and data entry id.
+// The prediction is stored in |out_prediction|.
+// Function returns false when the prediction couldn't be computed, e.g. because
+// not all entry points were available.
+template <class CornerTableT, typename DataTypeT>
+inline bool ComputeParallelogramPrediction(
+    int data_entry_id, const CornerIndex ci, const CornerTableT *table,
+    const std::vector<int32_t> &vertex_to_data_map, const DataTypeT *in_data,
+    int num_components, DataTypeT *out_prediction) {
+  const CornerIndex oci = table->Opposite(ci);
+  if (oci == kInvalidCornerIndex) {
+    return false;
+  }
+  int vert_opp, vert_next, vert_prev;
+  GetParallelogramEntries<CornerTableT>(oci, table, vertex_to_data_map,
+                                        &vert_opp, &vert_next, &vert_prev);
+  if (vert_opp < data_entry_id && vert_next < data_entry_id &&
+      vert_prev < data_entry_id) {
+    // Apply the parallelogram prediction.
+    const int v_opp_off = vert_opp * num_components;
+    const int v_next_off = vert_next * num_components;
+    const int v_prev_off = vert_prev * num_components;
+    for (int c = 0; c < num_components; ++c) {
+      const int64_t in_data_next_off = in_data[v_next_off + c];
+      const int64_t in_data_prev_off = in_data[v_prev_off + c];
+      const int64_t in_data_opp_off = in_data[v_opp_off + c];
+      const int64_t result =
+          (in_data_next_off + in_data_prev_off) - in_data_opp_off;
+
+      out_prediction[c] = static_cast<DataTypeT>(result);
+    }
+    return true;
+  }
+  return false;  // Not all data is available for prediction
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_PARALLELOGRAM_SHARED_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_decoder.h

@@ -0,0 +1,344 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_DECODER_H_
+
+#include <math.h>
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/bit_coders/rans_bit_decoder.h"
+#include "draco/core/varint_decoding.h"
+#include "draco/core/vector_d.h"
+#include "draco/draco_features.h"
+#include "draco/mesh/corner_table.h"
+
+namespace draco {
+
+// Decoder for predictions of UV coordinates encoded by our specialized texture
+// coordinate predictor. See the corresponding encoder for more details. Note
+// that this predictor is not portable and should not be used anymore. See
+// MeshPredictionSchemeTexCoordsPortableEncoder/Decoder for a portable version
+// of this prediction scheme.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeTexCoordsDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeTexCoordsDecoder(const PointAttribute *attribute,
+                                       const TransformT &transform,
+                                       const MeshDataT &mesh_data, int version)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        pos_attribute_(nullptr),
+        entry_to_point_id_map_(nullptr),
+        num_components_(0),
+        version_(version) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+
+  bool DecodePredictionData(DecoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_TEX_COORDS_DEPRECATED;
+  }
+
+  bool IsInitialized() const override {
+    if (pos_attribute_ == nullptr) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (att == nullptr) {
+      return false;
+    }
+    if (att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    pos_attribute_ = att;
+    return true;
+  }
+
+ protected:
+  Vector3f GetPositionForEntryId(int entry_id) const {
+    const PointIndex point_id = entry_to_point_id_map_[entry_id];
+    Vector3f pos;
+    pos_attribute_->ConvertValue(pos_attribute_->mapped_index(point_id),
+                                 &pos[0]);
+    return pos;
+  }
+
+  Vector2f GetTexCoordForEntryId(int entry_id, const DataTypeT *data) const {
+    const int data_offset = entry_id * num_components_;
+    return Vector2f(static_cast<float>(data[data_offset]),
+                    static_cast<float>(data[data_offset + 1]));
+  }
+
+  void ComputePredictedValue(CornerIndex corner_id, const DataTypeT *data,
+                             int data_id);
+
+ private:
+  const PointAttribute *pos_attribute_;
+  const PointIndex *entry_to_point_id_map_;
+  std::unique_ptr<DataTypeT[]> predicted_value_;
+  int num_components_;
+  // Encoded / decoded array of UV flips.
+  std::vector<bool> orientations_;
+  int version_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsDecoder<DataTypeT, TransformT, MeshDataT>::
+    ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                          int /* size */, int num_components,
+                          const PointIndex *entry_to_point_id_map) {
+  num_components_ = num_components;
+  entry_to_point_id_map_ = entry_to_point_id_map;
+  predicted_value_ =
+      std::unique_ptr<DataTypeT[]>(new DataTypeT[num_components]);
+  this->transform().Init(num_components);
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+  for (int p = 0; p < corner_map_size; ++p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    ComputePredictedValue(corner_id, out_data, p);
+
+    const int dst_offset = p * num_components;
+    this->transform().ComputeOriginalValue(
+        predicted_value_.get(), in_corr + dst_offset, out_data + dst_offset);
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsDecoder<DataTypeT, TransformT, MeshDataT>::
+    DecodePredictionData(DecoderBuffer *buffer) {
+  // Decode the delta coded orientations.
+  uint32_t num_orientations = 0;
+  if (buffer->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 2)) {
+    if (!buffer->Decode(&num_orientations)) {
+      return false;
+    }
+  } else {
+    if (!DecodeVarint(&num_orientations, buffer)) {
+      return false;
+    }
+  }
+  if (num_orientations == 0) {
+    return false;
+  }
+  orientations_.resize(num_orientations);
+  bool last_orientation = true;
+  RAnsBitDecoder decoder;
+  if (!decoder.StartDecoding(buffer)) {
+    return false;
+  }
+  for (uint32_t i = 0; i < num_orientations; ++i) {
+    if (!decoder.DecodeNextBit()) {
+      last_orientation = !last_orientation;
+    }
+    orientations_[i] = last_orientation;
+  }
+  decoder.EndDecoding();
+  return MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                     MeshDataT>::DecodePredictionData(buffer);
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+void MeshPredictionSchemeTexCoordsDecoder<DataTypeT, TransformT, MeshDataT>::
+    ComputePredictedValue(CornerIndex corner_id, const DataTypeT *data,
+                          int data_id) {
+  // Compute the predicted UV coordinate from the positions on all corners
+  // of the processed triangle. For the best prediction, the UV coordinates
+  // on the next/previous corners need to be already encoded/decoded.
+  const CornerIndex next_corner_id =
+      this->mesh_data().corner_table()->Next(corner_id);
+  const CornerIndex prev_corner_id =
+      this->mesh_data().corner_table()->Previous(corner_id);
+  // Get the encoded data ids from the next and previous corners.
+  // The data id is the encoding order of the UV coordinates.
+  int next_data_id, prev_data_id;
+
+  int next_vert_id, prev_vert_id;
+  next_vert_id =
+      this->mesh_data().corner_table()->Vertex(next_corner_id).value();
+  prev_vert_id =
+      this->mesh_data().corner_table()->Vertex(prev_corner_id).value();
+
+  next_data_id = this->mesh_data().vertex_to_data_map()->at(next_vert_id);
+  prev_data_id = this->mesh_data().vertex_to_data_map()->at(prev_vert_id);
+
+  if (prev_data_id < data_id && next_data_id < data_id) {
+    // Both other corners have available UV coordinates for prediction.
+    const Vector2f n_uv = GetTexCoordForEntryId(next_data_id, data);
+    const Vector2f p_uv = GetTexCoordForEntryId(prev_data_id, data);
+    if (p_uv == n_uv) {
+      // We cannot do a reliable prediction on degenerated UV triangles.
+      predicted_value_[0] = static_cast<int>(p_uv[0]);
+      predicted_value_[1] = static_cast<int>(p_uv[1]);
+      return;
+    }
+
+    // Get positions at all corners.
+    const Vector3f tip_pos = GetPositionForEntryId(data_id);
+    const Vector3f next_pos = GetPositionForEntryId(next_data_id);
+    const Vector3f prev_pos = GetPositionForEntryId(prev_data_id);
+    // Use the positions of the above triangle to predict the texture coordinate
+    // on the tip corner C.
+    // Convert the triangle into a new coordinate system defined by orthogonal
+    // bases vectors S, T, where S is vector prev_pos - next_pos and T is an
+    // perpendicular vector to S in the same plane as vector the
+    // tip_pos - next_pos.
+    // The transformed triangle in the new coordinate system is then going to
+    // be represented as:
+    //
+    //        1 ^
+    //          |
+    //          |
+    //          |   C
+    //          |  /  \
+    //          | /      \
+    //          |/          \
+    //          N--------------P
+    //          0              1
+    //
+    // Where next_pos point (N) is at position (0, 0), prev_pos point (P) is
+    // at (1, 0). Our goal is to compute the position of the tip_pos point (C)
+    // in this new coordinate space (s, t).
+    //
+    const Vector3f pn = prev_pos - next_pos;
+    const Vector3f cn = tip_pos - next_pos;
+    const float pn_norm2_squared = pn.SquaredNorm();
+    // Coordinate s of the tip corner C is simply the dot product of the
+    // normalized vectors |pn| and |cn| (normalized by the length of |pn|).
+    // Since both of these vectors are normalized, we don't need to perform the
+    // normalization explicitly and instead we can just use the squared norm
+    // of |pn| as a denominator of the resulting dot product of non normalized
+    // vectors.
+    float s, t;
+    // |pn_norm2_squared| can be exactly 0 when the next_pos and prev_pos are
+    // the same positions (e.g. because they were quantized to the same
+    // location).
+    if (version_ < DRACO_BITSTREAM_VERSION(1, 2) || pn_norm2_squared > 0) {
+      s = pn.Dot(cn) / pn_norm2_squared;
+      // To get the coordinate t, we can use formula:
+      //      t = |C-N - (P-N) * s| / |P-N|
+      // Do not use std::sqrt to avoid changes in the bitstream.
+      t = sqrt((cn - pn * s).SquaredNorm() / pn_norm2_squared);
+    } else {
+      s = 0;
+      t = 0;
+    }
+
+    // Now we need to transform the point (s, t) to the texture coordinate space
+    // UV. We know the UV coordinates on points N and P (N_UV and P_UV). Lets
+    // denote P_UV - N_UV = PN_UV. PN_UV is then 2 dimensional vector that can
+    // be used to define transformation from the normalized coordinate system
+    // to the texture coordinate system using a 3x3 affine matrix M:
+    //
+    //  M = | PN_UV[0]  -PN_UV[1]  N_UV[0] |
+    //      | PN_UV[1]   PN_UV[0]  N_UV[1] |
+    //      | 0          0         1       |
+    //
+    // The predicted point C_UV in the texture space is then equal to
+    // C_UV = M * (s, t, 1). Because the triangle in UV space may be flipped
+    // around the PN_UV axis, we also need to consider point C_UV' = M * (s, -t)
+    // as the prediction.
+    const Vector2f pn_uv = p_uv - n_uv;
+    const float pnus = pn_uv[0] * s + n_uv[0];
+    const float pnut = pn_uv[0] * t;
+    const float pnvs = pn_uv[1] * s + n_uv[1];
+    const float pnvt = pn_uv[1] * t;
+    Vector2f predicted_uv;
+
+    // When decoding the data, we already know which orientation to use.
+    const bool orientation = orientations_.back();
+    orientations_.pop_back();
+    if (orientation)
+      predicted_uv = Vector2f(pnus - pnvt, pnvs + pnut);
+    else
+      predicted_uv = Vector2f(pnus + pnvt, pnvs - pnut);
+
+    if (std::is_integral<DataTypeT>::value) {
+      // Round the predicted value for integer types.
+      if (std::isnan(predicted_uv[0])) {
+        predicted_value_[0] = INT_MIN;
+      } else {
+        predicted_value_[0] = static_cast<int>(floor(predicted_uv[0] + 0.5));
+      }
+      if (std::isnan(predicted_uv[1])) {
+        predicted_value_[1] = INT_MIN;
+      } else {
+        predicted_value_[1] = static_cast<int>(floor(predicted_uv[1] + 0.5));
+      }
+    } else {
+      predicted_value_[0] = static_cast<int>(predicted_uv[0]);
+      predicted_value_[1] = static_cast<int>(predicted_uv[1]);
+    }
+    return;
+  }
+  // Else we don't have available textures on both corners. For such case we
+  // can't use positions for predicting the uv value and we resort to delta
+  // coding.
+  int data_offset = 0;
+  if (prev_data_id < data_id) {
+    // Use the value on the previous corner as the prediction.
+    data_offset = prev_data_id * num_components_;
+  }
+  if (next_data_id < data_id) {
+    // Use the value on the next corner as the prediction.
+    data_offset = next_data_id * num_components_;
+  } else {
+    // None of the other corners have a valid value. Use the last encoded value
+    // as the prediction if possible.
+    if (data_id > 0) {
+      data_offset = (data_id - 1) * num_components_;
+    } else {
+      // We are encoding the first value. Predict 0.
+      for (int i = 0; i < num_components_; ++i) {
+        predicted_value_[i] = 0;
+      }
+      return;
+    }
+  }
+  for (int i = 0; i < num_components_; ++i) {
+    predicted_value_[i] = data[data_offset + i];
+  }
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_DECODER_H_
+#endif

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_encoder.h

@@ -0,0 +1,318 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_ENCODER_H_
+
+#include <math.h>
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/bit_coders/rans_bit_encoder.h"
+#include "draco/core/varint_encoding.h"
+#include "draco/core/vector_d.h"
+#include "draco/mesh/corner_table.h"
+
+namespace draco {
+
+// Prediction scheme designed for predicting texture coordinates from known
+// spatial position of vertices. For good parametrization, the ratios between
+// triangle edge lengths should be about the same in both the spatial and UV
+// coordinate spaces, which makes the positions a good predictor for the UV
+// coordinates.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeTexCoordsEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeTexCoordsEncoder(const PointAttribute *attribute,
+                                       const TransformT &transform,
+                                       const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        pos_attribute_(nullptr),
+        entry_to_point_id_map_(nullptr),
+        num_components_(0) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+
+  bool EncodePredictionData(EncoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_TEX_COORDS_DEPRECATED;
+  }
+
+  bool IsInitialized() const override {
+    if (pos_attribute_ == nullptr) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    pos_attribute_ = att;
+    return true;
+  }
+
+ protected:
+  Vector3f GetPositionForEntryId(int entry_id) const {
+    const PointIndex point_id = entry_to_point_id_map_[entry_id];
+    Vector3f pos;
+    pos_attribute_->ConvertValue(pos_attribute_->mapped_index(point_id),
+                                 &pos[0]);
+    return pos;
+  }
+
+  Vector2f GetTexCoordForEntryId(int entry_id, const DataTypeT *data) const {
+    const int data_offset = entry_id * num_components_;
+    return Vector2f(static_cast<float>(data[data_offset]),
+                    static_cast<float>(data[data_offset + 1]));
+  }
+
+  void ComputePredictedValue(CornerIndex corner_id, const DataTypeT *data,
+                             int data_id);
+
+ private:
+  const PointAttribute *pos_attribute_;
+  const PointIndex *entry_to_point_id_map_;
+  std::unique_ptr<DataTypeT[]> predicted_value_;
+  int num_components_;
+  // Encoded / decoded array of UV flips.
+  std::vector<bool> orientations_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsEncoder<DataTypeT, TransformT, MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex *entry_to_point_id_map) {
+  num_components_ = num_components;
+  entry_to_point_id_map_ = entry_to_point_id_map;
+  predicted_value_ =
+      std::unique_ptr<DataTypeT[]>(new DataTypeT[num_components]);
+  this->transform().Init(in_data, size, num_components);
+  // We start processing from the end because this prediction uses data from
+  // previous entries that could be overwritten when an entry is processed.
+  for (int p =
+           static_cast<int>(this->mesh_data().data_to_corner_map()->size()) - 1;
+       p >= 0; --p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    ComputePredictedValue(corner_id, in_data, p);
+
+    const int dst_offset = p * num_components;
+    this->transform().ComputeCorrection(
+        in_data + dst_offset, predicted_value_.get(), out_corr + dst_offset);
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsEncoder<DataTypeT, TransformT, MeshDataT>::
+    EncodePredictionData(EncoderBuffer *buffer) {
+  // Encode the delta-coded orientations using arithmetic coding.
+  const uint32_t num_orientations = static_cast<uint32_t>(orientations_.size());
+  EncodeVarint(num_orientations, buffer);
+  bool last_orientation = true;
+  RAnsBitEncoder encoder;
+  encoder.StartEncoding();
+  for (bool orientation : orientations_) {
+    encoder.EncodeBit(orientation == last_orientation);
+    last_orientation = orientation;
+  }
+  encoder.EndEncoding(buffer);
+  return MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                     MeshDataT>::EncodePredictionData(buffer);
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+void MeshPredictionSchemeTexCoordsEncoder<DataTypeT, TransformT, MeshDataT>::
+    ComputePredictedValue(CornerIndex corner_id, const DataTypeT *data,
+                          int data_id) {
+  // Compute the predicted UV coordinate from the positions on all corners
+  // of the processed triangle. For the best prediction, the UV coordinates
+  // on the next/previous corners need to be already encoded/decoded.
+  const CornerIndex next_corner_id =
+      this->mesh_data().corner_table()->Next(corner_id);
+  const CornerIndex prev_corner_id =
+      this->mesh_data().corner_table()->Previous(corner_id);
+  // Get the encoded data ids from the next and previous corners.
+  // The data id is the encoding order of the UV coordinates.
+  int next_data_id, prev_data_id;
+
+  int next_vert_id, prev_vert_id;
+  next_vert_id =
+      this->mesh_data().corner_table()->Vertex(next_corner_id).value();
+  prev_vert_id =
+      this->mesh_data().corner_table()->Vertex(prev_corner_id).value();
+
+  next_data_id = this->mesh_data().vertex_to_data_map()->at(next_vert_id);
+  prev_data_id = this->mesh_data().vertex_to_data_map()->at(prev_vert_id);
+
+  if (prev_data_id < data_id && next_data_id < data_id) {
+    // Both other corners have available UV coordinates for prediction.
+    const Vector2f n_uv = GetTexCoordForEntryId(next_data_id, data);
+    const Vector2f p_uv = GetTexCoordForEntryId(prev_data_id, data);
+    if (p_uv == n_uv) {
+      // We cannot do a reliable prediction on degenerated UV triangles.
+      predicted_value_[0] = static_cast<int>(p_uv[0]);
+      predicted_value_[1] = static_cast<int>(p_uv[1]);
+      return;
+    }
+
+    // Get positions at all corners.
+    const Vector3f tip_pos = GetPositionForEntryId(data_id);
+    const Vector3f next_pos = GetPositionForEntryId(next_data_id);
+    const Vector3f prev_pos = GetPositionForEntryId(prev_data_id);
+    // Use the positions of the above triangle to predict the texture coordinate
+    // on the tip corner C.
+    // Convert the triangle into a new coordinate system defined by orthogonal
+    // bases vectors S, T, where S is vector prev_pos - next_pos and T is an
+    // perpendicular vector to S in the same plane as vector the
+    // tip_pos - next_pos.
+    // The transformed triangle in the new coordinate system is then going to
+    // be represented as:
+    //
+    //        1 ^
+    //          |
+    //          |
+    //          |   C
+    //          |  /  \
+    //          | /      \
+    //          |/          \
+    //          N--------------P
+    //          0              1
+    //
+    // Where next_pos point (N) is at position (0, 0), prev_pos point (P) is
+    // at (1, 0). Our goal is to compute the position of the tip_pos point (C)
+    // in this new coordinate space (s, t).
+    //
+    const Vector3f pn = prev_pos - next_pos;
+    const Vector3f cn = tip_pos - next_pos;
+    const float pn_norm2_squared = pn.SquaredNorm();
+    // Coordinate s of the tip corner C is simply the dot product of the
+    // normalized vectors |pn| and |cn| (normalized by the length of |pn|).
+    // Since both of these vectors are normalized, we don't need to perform the
+    // normalization explicitly and instead we can just use the squared norm
+    // of |pn| as a denominator of the resulting dot product of non normalized
+    // vectors.
+    float s, t;
+    // |pn_norm2_squared| can be exactly 0 when the next_pos and prev_pos are
+    // the same positions (e.g. because they were quantized to the same
+    // location).
+    if (pn_norm2_squared > 0) {
+      s = pn.Dot(cn) / pn_norm2_squared;
+      // To get the coordinate t, we can use formula:
+      //      t = |C-N - (P-N) * s| / |P-N|
+      // Do not use std::sqrt to avoid changes in the bitstream.
+      t = sqrt((cn - pn * s).SquaredNorm() / pn_norm2_squared);
+    } else {
+      s = 0;
+      t = 0;
+    }
+
+    // Now we need to transform the point (s, t) to the texture coordinate space
+    // UV. We know the UV coordinates on points N and P (N_UV and P_UV). Lets
+    // denote P_UV - N_UV = PN_UV. PN_UV is then 2 dimensional vector that can
+    // be used to define transformation from the normalized coordinate system
+    // to the texture coordinate system using a 3x3 affine matrix M:
+    //
+    //  M = | PN_UV[0]  -PN_UV[1]  N_UV[0] |
+    //      | PN_UV[1]   PN_UV[0]  N_UV[1] |
+    //      | 0          0         1       |
+    //
+    // The predicted point C_UV in the texture space is then equal to
+    // C_UV = M * (s, t, 1). Because the triangle in UV space may be flipped
+    // around the PN_UV axis, we also need to consider point C_UV' = M * (s, -t)
+    // as the prediction.
+    const Vector2f pn_uv = p_uv - n_uv;
+    const float pnus = pn_uv[0] * s + n_uv[0];
+    const float pnut = pn_uv[0] * t;
+    const float pnvs = pn_uv[1] * s + n_uv[1];
+    const float pnvt = pn_uv[1] * t;
+    Vector2f predicted_uv;
+
+    // When encoding compute both possible vectors and determine which one
+    // results in a better prediction.
+    const Vector2f predicted_uv_0(pnus - pnvt, pnvs + pnut);
+    const Vector2f predicted_uv_1(pnus + pnvt, pnvs - pnut);
+    const Vector2f c_uv = GetTexCoordForEntryId(data_id, data);
+    if ((c_uv - predicted_uv_0).SquaredNorm() <
+        (c_uv - predicted_uv_1).SquaredNorm()) {
+      predicted_uv = predicted_uv_0;
+      orientations_.push_back(true);
+    } else {
+      predicted_uv = predicted_uv_1;
+      orientations_.push_back(false);
+    }
+    if (std::is_integral<DataTypeT>::value) {
+      // Round the predicted value for integer types.
+      predicted_value_[0] = static_cast<int>(floor(predicted_uv[0] + 0.5));
+      predicted_value_[1] = static_cast<int>(floor(predicted_uv[1] + 0.5));
+    } else {
+      predicted_value_[0] = static_cast<int>(predicted_uv[0]);
+      predicted_value_[1] = static_cast<int>(predicted_uv[1]);
+    }
+    return;
+  }
+  // Else we don't have available textures on both corners. For such case we
+  // can't use positions for predicting the uv value and we resort to delta
+  // coding.
+  int data_offset = 0;
+  if (prev_data_id < data_id) {
+    // Use the value on the previous corner as the prediction.
+    data_offset = prev_data_id * num_components_;
+  }
+  if (next_data_id < data_id) {
+    // Use the value on the next corner as the prediction.
+    data_offset = next_data_id * num_components_;
+  } else {
+    // None of the other corners have a valid value. Use the last encoded value
+    // as the prediction if possible.
+    if (data_id > 0) {
+      data_offset = (data_id - 1) * num_components_;
+    } else {
+      // We are encoding the first value. Predict 0.
+      for (int i = 0; i < num_components_; ++i) {
+        predicted_value_[i] = 0;
+      }
+      return;
+    }
+  }
+  for (int i = 0; i < num_components_; ++i) {
+    predicted_value_[i] = data[data_offset + i];
+  }
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_decoder.h

@@ -0,0 +1,143 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_predictor.h"
+#include "draco/compression/bit_coders/rans_bit_decoder.h"
+
+namespace draco {
+
+// Decoder for predictions of UV coordinates encoded by our specialized and
+// portable texture coordinate predictor. See the corresponding encoder for more
+// details.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeTexCoordsPortableDecoder
+    : public MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeTexCoordsPortableDecoder(const PointAttribute *attribute,
+                                               const TransformT &transform,
+                                               const MeshDataT &mesh_data)
+      : MeshPredictionSchemeDecoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        predictor_(mesh_data) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+
+  bool DecodePredictionData(DecoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_TEX_COORDS_PORTABLE;
+  }
+
+  bool IsInitialized() const override {
+    if (!predictor_.IsInitialized()) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (!att || att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    predictor_.SetPositionAttribute(*att);
+    return true;
+  }
+
+ private:
+  MeshPredictionSchemeTexCoordsPortablePredictor<DataTypeT, MeshDataT>
+      predictor_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsPortableDecoder<
+    DataTypeT, TransformT,
+    MeshDataT>::ComputeOriginalValues(const CorrType *in_corr,
+                                      DataTypeT *out_data, int /* size */,
+                                      int num_components,
+                                      const PointIndex *entry_to_point_id_map) {
+  if (num_components != MeshPredictionSchemeTexCoordsPortablePredictor<
+                            DataTypeT, MeshDataT>::kNumComponents) {
+    return false;
+  }
+  predictor_.SetEntryToPointIdMap(entry_to_point_id_map);
+  this->transform().Init(num_components);
+
+  const int corner_map_size =
+      static_cast<int>(this->mesh_data().data_to_corner_map()->size());
+  for (int p = 0; p < corner_map_size; ++p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    if (!predictor_.template ComputePredictedValue<false>(corner_id, out_data,
+                                                          p)) {
+      return false;
+    }
+
+    const int dst_offset = p * num_components;
+    this->transform().ComputeOriginalValue(predictor_.predicted_value(),
+                                           in_corr + dst_offset,
+                                           out_data + dst_offset);
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsPortableDecoder<
+    DataTypeT, TransformT, MeshDataT>::DecodePredictionData(DecoderBuffer
+                                                                *buffer) {
+  // Decode the delta coded orientations.
+  int32_t num_orientations = 0;
+  if (!buffer->Decode(&num_orientations) || num_orientations < 0) {
+    return false;
+  }
+  predictor_.ResizeOrientations(num_orientations);
+  bool last_orientation = true;
+  RAnsBitDecoder decoder;
+  if (!decoder.StartDecoding(buffer)) {
+    return false;
+  }
+  for (int i = 0; i < num_orientations; ++i) {
+    if (!decoder.DecodeNextBit()) {
+      last_orientation = !last_orientation;
+    }
+    predictor_.set_orientation(i, last_orientation);
+  }
+  decoder.EndDecoding();
+  return MeshPredictionSchemeDecoder<DataTypeT, TransformT,
+                                     MeshDataT>::DecodePredictionData(buffer);
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_encoder.h

@@ -0,0 +1,133 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_predictor.h"
+#include "draco/compression/bit_coders/rans_bit_encoder.h"
+
+namespace draco {
+
+// Prediction scheme designed for predicting texture coordinates from known
+// spatial position of vertices. For isometric parametrizations, the ratios
+// between triangle edge lengths should be about the same in both the spatial
+// and UV coordinate spaces, which makes the positions a good predictor for the
+// UV coordinates. Note that this may not be the optimal approach for other
+// parametrizations such as projective ones.
+template <typename DataTypeT, class TransformT, class MeshDataT>
+class MeshPredictionSchemeTexCoordsPortableEncoder
+    : public MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT> {
+ public:
+  using CorrType = typename MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                                        MeshDataT>::CorrType;
+  MeshPredictionSchemeTexCoordsPortableEncoder(const PointAttribute *attribute,
+                                               const TransformT &transform,
+                                               const MeshDataT &mesh_data)
+      : MeshPredictionSchemeEncoder<DataTypeT, TransformT, MeshDataT>(
+            attribute, transform, mesh_data),
+        predictor_(mesh_data) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+
+  bool EncodePredictionData(EncoderBuffer *buffer) override;
+
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return MESH_PREDICTION_TEX_COORDS_PORTABLE;
+  }
+
+  bool IsInitialized() const override {
+    if (!predictor_.IsInitialized()) {
+      return false;
+    }
+    if (!this->mesh_data().IsInitialized()) {
+      return false;
+    }
+    return true;
+  }
+
+  int GetNumParentAttributes() const override { return 1; }
+
+  GeometryAttribute::Type GetParentAttributeType(int i) const override {
+    DRACO_DCHECK_EQ(i, 0);
+    (void)i;
+    return GeometryAttribute::POSITION;
+  }
+
+  bool SetParentAttribute(const PointAttribute *att) override {
+    if (att->attribute_type() != GeometryAttribute::POSITION) {
+      return false;  // Invalid attribute type.
+    }
+    if (att->num_components() != 3) {
+      return false;  // Currently works only for 3 component positions.
+    }
+    predictor_.SetPositionAttribute(*att);
+    return true;
+  }
+
+ private:
+  MeshPredictionSchemeTexCoordsPortablePredictor<DataTypeT, MeshDataT>
+      predictor_;
+};
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsPortableEncoder<DataTypeT, TransformT,
+                                                  MeshDataT>::
+    ComputeCorrectionValues(const DataTypeT *in_data, CorrType *out_corr,
+                            int size, int num_components,
+                            const PointIndex *entry_to_point_id_map) {
+  predictor_.SetEntryToPointIdMap(entry_to_point_id_map);
+  this->transform().Init(in_data, size, num_components);
+  // We start processing from the end because this prediction uses data from
+  // previous entries that could be overwritten when an entry is processed.
+  for (int p =
+           static_cast<int>(this->mesh_data().data_to_corner_map()->size() - 1);
+       p >= 0; --p) {
+    const CornerIndex corner_id = this->mesh_data().data_to_corner_map()->at(p);
+    predictor_.template ComputePredictedValue<true>(corner_id, in_data, p);
+
+    const int dst_offset = p * num_components;
+    this->transform().ComputeCorrection(in_data + dst_offset,
+                                        predictor_.predicted_value(),
+                                        out_corr + dst_offset);
+  }
+  return true;
+}
+
+template <typename DataTypeT, class TransformT, class MeshDataT>
+bool MeshPredictionSchemeTexCoordsPortableEncoder<
+    DataTypeT, TransformT, MeshDataT>::EncodePredictionData(EncoderBuffer
+                                                                *buffer) {
+  // Encode the delta-coded orientations using arithmetic coding.
+  const int32_t num_orientations = predictor_.num_orientations();
+  buffer->Encode(num_orientations);
+  bool last_orientation = true;
+  RAnsBitEncoder encoder;
+  encoder.StartEncoding();
+  for (int i = 0; i < num_orientations; ++i) {
+    const bool orientation = predictor_.orientation(i);
+    encoder.EncodeBit(orientation == last_orientation);
+    last_orientation = orientation;
+  }
+  encoder.EndEncoding(buffer);
+  return MeshPredictionSchemeEncoder<DataTypeT, TransformT,
+                                     MeshDataT>::EncodePredictionData(buffer);
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_predictor.h

@@ -0,0 +1,263 @@
+// Copyright 2017 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_PREDICTOR_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_PREDICTOR_H_
+
+#include <math.h>
+
+#include "draco/attributes/point_attribute.h"
+#include "draco/core/math_utils.h"
+#include "draco/core/vector_d.h"
+#include "draco/mesh/corner_table.h"
+
+namespace draco {
+
+// Predictor functionality used for portable UV prediction by both encoder and
+// decoder.
+template <typename DataTypeT, class MeshDataT>
+class MeshPredictionSchemeTexCoordsPortablePredictor {
+ public:
+  static constexpr int kNumComponents = 2;
+
+  explicit MeshPredictionSchemeTexCoordsPortablePredictor(const MeshDataT &md)
+      : pos_attribute_(nullptr),
+        entry_to_point_id_map_(nullptr),
+        mesh_data_(md) {}
+  void SetPositionAttribute(const PointAttribute &position_attribute) {
+    pos_attribute_ = &position_attribute;
+  }
+  void SetEntryToPointIdMap(const PointIndex *map) {
+    entry_to_point_id_map_ = map;
+  }
+  bool IsInitialized() const { return pos_attribute_ != nullptr; }
+
+  VectorD<int64_t, 3> GetPositionForEntryId(int entry_id) const {
+    const PointIndex point_id = entry_to_point_id_map_[entry_id];
+    VectorD<int64_t, 3> pos;
+    pos_attribute_->ConvertValue(pos_attribute_->mapped_index(point_id),
+                                 &pos[0]);
+    return pos;
+  }
+
+  VectorD<int64_t, 2> GetTexCoordForEntryId(int entry_id,
+                                            const DataTypeT *data) const {
+    const int data_offset = entry_id * kNumComponents;
+    return VectorD<int64_t, 2>(data[data_offset], data[data_offset + 1]);
+  }
+
+  // Computes predicted UV coordinates on a given corner. The coordinates are
+  // stored in |predicted_value_| member.
+  template <bool is_encoder_t>
+  bool ComputePredictedValue(CornerIndex corner_id, const DataTypeT *data,
+                             int data_id);
+
+  const DataTypeT *predicted_value() const { return predicted_value_; }
+  bool orientation(int i) const { return orientations_[i]; }
+  void set_orientation(int i, bool v) { orientations_[i] = v; }
+  size_t num_orientations() const { return orientations_.size(); }
+  void ResizeOrientations(int num_orientations) {
+    orientations_.resize(num_orientations);
+  }
+
+ private:
+  const PointAttribute *pos_attribute_;
+  const PointIndex *entry_to_point_id_map_;
+  DataTypeT predicted_value_[kNumComponents];
+  // Encoded / decoded array of UV flips.
+  // TODO(ostava): We should remove this and replace this with in-place encoding
+  // and decoding to avoid unnecessary copy.
+  std::vector<bool> orientations_;
+  MeshDataT mesh_data_;
+};
+
+template <typename DataTypeT, class MeshDataT>
+template <bool is_encoder_t>
+bool MeshPredictionSchemeTexCoordsPortablePredictor<
+    DataTypeT, MeshDataT>::ComputePredictedValue(CornerIndex corner_id,
+                                                 const DataTypeT *data,
+                                                 int data_id) {
+  // Compute the predicted UV coordinate from the positions on all corners
+  // of the processed triangle. For the best prediction, the UV coordinates
+  // on the next/previous corners need to be already encoded/decoded.
+  const CornerIndex next_corner_id = mesh_data_.corner_table()->Next(corner_id);
+  const CornerIndex prev_corner_id =
+      mesh_data_.corner_table()->Previous(corner_id);
+  // Get the encoded data ids from the next and previous corners.
+  // The data id is the encoding order of the UV coordinates.
+  int next_data_id, prev_data_id;
+
+  int next_vert_id, prev_vert_id;
+  next_vert_id = mesh_data_.corner_table()->Vertex(next_corner_id).value();
+  prev_vert_id = mesh_data_.corner_table()->Vertex(prev_corner_id).value();
+
+  next_data_id = mesh_data_.vertex_to_data_map()->at(next_vert_id);
+  prev_data_id = mesh_data_.vertex_to_data_map()->at(prev_vert_id);
+
+  if (prev_data_id < data_id && next_data_id < data_id) {
+    // Both other corners have available UV coordinates for prediction.
+    const VectorD<int64_t, 2> n_uv = GetTexCoordForEntryId(next_data_id, data);
+    const VectorD<int64_t, 2> p_uv = GetTexCoordForEntryId(prev_data_id, data);
+    if (p_uv == n_uv) {
+      // We cannot do a reliable prediction on degenerated UV triangles.
+      predicted_value_[0] = p_uv[0];
+      predicted_value_[1] = p_uv[1];
+      return true;
+    }
+
+    // Get positions at all corners.
+    const VectorD<int64_t, 3> tip_pos = GetPositionForEntryId(data_id);
+    const VectorD<int64_t, 3> next_pos = GetPositionForEntryId(next_data_id);
+    const VectorD<int64_t, 3> prev_pos = GetPositionForEntryId(prev_data_id);
+    // We use the positions of the above triangle to predict the texture
+    // coordinate on the tip corner C.
+    // To convert the triangle into the UV coordinate system we first compute
+    // position X on the vector |prev_pos - next_pos| that is the projection of
+    // point C onto vector |prev_pos - next_pos|:
+    //
+    //              C
+    //             /.  \
+    //            / .     \
+    //           /  .        \
+    //          N---X----------P
+    //
+    // Where next_pos is point (N), prev_pos is point (P) and tip_pos is the
+    // position of predicted coordinate (C).
+    //
+    const VectorD<int64_t, 3> pn = prev_pos - next_pos;
+    const uint64_t pn_norm2_squared = pn.SquaredNorm();
+    if (pn_norm2_squared != 0) {
+      // Compute the projection of C onto PN by computing dot product of CN with
+      // PN and normalizing it by length of PN. This gives us a factor |s| where
+      // |s = PN.Dot(CN) / PN.SquaredNorm2()|. This factor can be used to
+      // compute X in UV space |X_UV| as |X_UV = N_UV + s * PN_UV|.
+      const VectorD<int64_t, 3> cn = tip_pos - next_pos;
+      const int64_t cn_dot_pn = pn.Dot(cn);
+
+      const VectorD<int64_t, 2> pn_uv = p_uv - n_uv;
+      // Because we perform all computations with integers, we don't explicitly
+      // compute the normalized factor |s|, but rather we perform all operations
+      // over UV vectors in a non-normalized coordinate system scaled with a
+      // scaling factor |pn_norm2_squared|:
+      //
+      //      x_uv = X_UV * PN.Norm2Squared()
+      //
+      const VectorD<int64_t, 2> x_uv =
+          n_uv * pn_norm2_squared + (cn_dot_pn * pn_uv);
+
+      const int64_t pn_absmax_element =
+          std::max(std::max(std::abs(pn[0]), std::abs(pn[1])), std::abs(pn[2]));
+      if (cn_dot_pn > std::numeric_limits<int64_t>::max() / pn_absmax_element) {
+        // return false if squared length calculation would overflow.
+        return false;
+      }
+
+      // Compute squared length of vector CX in position coordinate system:
+      const VectorD<int64_t, 3> x_pos =
+          next_pos + (cn_dot_pn * pn) / pn_norm2_squared;
+      const uint64_t cx_norm2_squared = (tip_pos - x_pos).SquaredNorm();
+
+      // Compute vector CX_UV in the uv space by rotating vector PN_UV by 90
+      // degrees and scaling it with factor CX.Norm2() / PN.Norm2():
+      //
+      //     CX_UV = (CX.Norm2() / PN.Norm2()) * Rot(PN_UV)
+      //
+      // To preserve precision, we perform all operations in scaled space as
+      // explained above, so we want the final vector to be:
+      //
+      //     cx_uv = CX_UV * PN.Norm2Squared()
+      //
+      // We can then rewrite the formula as:
+      //
+      //     cx_uv = CX.Norm2() * PN.Norm2() * Rot(PN_UV)
+      //
+      VectorD<int64_t, 2> cx_uv(pn_uv[1], -pn_uv[0]);  // Rotated PN_UV.
+      // Compute CX.Norm2() * PN.Norm2()
+      const uint64_t norm_squared =
+          IntSqrt(cx_norm2_squared * pn_norm2_squared);
+      // Final cx_uv in the scaled coordinate space.
+      cx_uv = cx_uv * norm_squared;
+
+      // Predicted uv coordinate is then computed by either adding or
+      // subtracting CX_UV to/from X_UV.
+      VectorD<int64_t, 2> predicted_uv;
+      if (is_encoder_t) {
+        // When encoding, compute both possible vectors and determine which one
+        // results in a better prediction.
+        // Both vectors need to be transformed back from the scaled space to
+        // the real UV coordinate space.
+        const VectorD<int64_t, 2> predicted_uv_0((x_uv + cx_uv) /
+                                                 pn_norm2_squared);
+        const VectorD<int64_t, 2> predicted_uv_1((x_uv - cx_uv) /
+                                                 pn_norm2_squared);
+        const VectorD<int64_t, 2> c_uv = GetTexCoordForEntryId(data_id, data);
+        if ((c_uv - predicted_uv_0).SquaredNorm() <
+            (c_uv - predicted_uv_1).SquaredNorm()) {
+          predicted_uv = predicted_uv_0;
+          orientations_.push_back(true);
+        } else {
+          predicted_uv = predicted_uv_1;
+          orientations_.push_back(false);
+        }
+      } else {
+        // When decoding the data, we already know which orientation to use.
+        if (orientations_.empty()) {
+          return false;
+        }
+        const bool orientation = orientations_.back();
+        orientations_.pop_back();
+        if (orientation) {
+          predicted_uv = (x_uv + cx_uv) / pn_norm2_squared;
+        } else {
+          predicted_uv = (x_uv - cx_uv) / pn_norm2_squared;
+        }
+      }
+      predicted_value_[0] = static_cast<int>(predicted_uv[0]);
+      predicted_value_[1] = static_cast<int>(predicted_uv[1]);
+      return true;
+    }
+  }
+  // Else we don't have available textures on both corners or the position data
+  // is invalid. For such cases we can't use positions for predicting the uv
+  // value and we resort to delta coding.
+  int data_offset = 0;
+  if (prev_data_id < data_id) {
+    // Use the value on the previous corner as the prediction.
+    data_offset = prev_data_id * kNumComponents;
+  }
+  if (next_data_id < data_id) {
+    // Use the value on the next corner as the prediction.
+    data_offset = next_data_id * kNumComponents;
+  } else {
+    // None of the other corners have a valid value. Use the last encoded value
+    // as the prediction if possible.
+    if (data_id > 0) {
+      data_offset = (data_id - 1) * kNumComponents;
+    } else {
+      // We are encoding the first value. Predict 0.
+      for (int i = 0; i < kNumComponents; ++i) {
+        predicted_value_[i] = 0;
+      }
+      return true;
+    }
+  }
+  for (int i = 0; i < kNumComponents; ++i) {
+    predicted_value_[i] = data[data_offset + i];
+  }
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_MESH_PREDICTION_SCHEME_TEX_COORDS_PORTABLE_PREDICTOR_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_decoder.h

@@ -0,0 +1,90 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_H_
+
+#include <type_traits>
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder_interface.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoding_transform.h"
+
+// Prediction schemes can be used during encoding and decoding of vertex
+// attributes to predict attribute values based on the previously
+// encoded/decoded data. The differences between the original and predicted
+// attribute values are used to compute correction values that can be usually
+// encoded with fewer bits compared to the original data.
+namespace draco {
+
+// Abstract base class for typed prediction schemes. It provides basic access
+// to the encoded attribute and to the supplied prediction transform.
+template <typename DataTypeT,
+          class TransformT =
+              PredictionSchemeDecodingTransform<DataTypeT, DataTypeT>>
+class PredictionSchemeDecoder : public PredictionSchemeTypedDecoderInterface<
+                                    DataTypeT, typename TransformT::CorrType> {
+ public:
+  typedef DataTypeT DataType;
+  typedef TransformT Transform;
+  // Correction type needs to be defined in the prediction transform class.
+  typedef typename Transform::CorrType CorrType;
+  explicit PredictionSchemeDecoder(const PointAttribute *attribute)
+      : PredictionSchemeDecoder(attribute, Transform()) {}
+  PredictionSchemeDecoder(const PointAttribute *attribute,
+                          const Transform &transform)
+      : attribute_(attribute), transform_(transform) {}
+
+  bool DecodePredictionData(DecoderBuffer *buffer) override {
+    if (!transform_.DecodeTransformData(buffer)) {
+      return false;
+    }
+    return true;
+  }
+
+  const PointAttribute *GetAttribute() const override { return attribute(); }
+
+  // Returns the number of parent attributes that are needed for the prediction.
+  int GetNumParentAttributes() const override { return 0; }
+
+  // Returns the type of each of the parent attribute.
+  GeometryAttribute::Type GetParentAttributeType(int /* i */) const override {
+    return GeometryAttribute::INVALID;
+  }
+
+  // Sets the required parent attribute.
+  bool SetParentAttribute(const PointAttribute * /* att */) override {
+    return false;
+  }
+
+  bool AreCorrectionsPositive() override {
+    return transform_.AreCorrectionsPositive();
+  }
+
+  PredictionSchemeTransformType GetTransformType() const override {
+    return transform_.GetType();
+  }
+
+ protected:
+  inline const PointAttribute *attribute() const { return attribute_; }
+  inline const Transform &transform() const { return transform_; }
+  inline Transform &transform() { return transform_; }
+
+ private:
+  const PointAttribute *attribute_;
+  Transform transform_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_decoder_factory.h

@@ -0,0 +1,194 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Functions for creating prediction schemes for decoders using the provided
+// prediction method id.
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_FACTORY_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_FACTORY_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_decoder.h"
+#include "draco/draco_features.h"
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_decoder.h"
+#endif
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_multi_parallelogram_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_delta_decoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_factory.h"
+#include "draco/compression/mesh/mesh_decoder.h"
+
+namespace draco {
+
+// Factory class for creating mesh prediction schemes. The factory implements
+// operator() that is used to create an appropriate mesh prediction scheme in
+// CreateMeshPredictionScheme() function in prediction_scheme_factory.h
+template <typename DataTypeT>
+struct MeshPredictionSchemeDecoderFactory {
+  // Operator () specialized for the wrap transform. Wrap transform can be used
+  // for all mesh prediction schemes. The specialization is done in compile time
+  // to prevent instantiations of unneeded combinations of prediction schemes +
+  // prediction transforms.
+  template <class TransformT, class MeshDataT,
+            PredictionSchemeTransformType Method>
+  struct DispatchFunctor {
+    std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>> operator()(
+        PredictionSchemeMethod method, const PointAttribute *attribute,
+        const TransformT &transform, const MeshDataT &mesh_data,
+        uint16_t bitstream_version) {
+      if (method == MESH_PREDICTION_PARALLELOGRAM) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeParallelogramDecoder<DataTypeT, TransformT,
+                                                         MeshDataT>(
+                attribute, transform, mesh_data));
+      }
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+      else if (method == MESH_PREDICTION_MULTI_PARALLELOGRAM) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeMultiParallelogramDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+#endif
+      else if (method == MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeConstrainedMultiParallelogramDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+      else if (method == MESH_PREDICTION_TEX_COORDS_DEPRECATED) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeTexCoordsDecoder<DataTypeT, TransformT,
+                                                     MeshDataT>(
+                attribute, transform, mesh_data, bitstream_version));
+      }
+#endif
+      else if (method == MESH_PREDICTION_TEX_COORDS_PORTABLE) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeTexCoordsPortableDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+      else if (method == MESH_PREDICTION_GEOMETRIC_NORMAL) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeGeometricNormalDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+#endif
+      return nullptr;
+    }
+  };
+
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+  // Operator () specialized for normal octahedron transforms. These transforms
+  // are currently used only by the geometric normal prediction scheme (the
+  // transform is also used by delta coding, but delta predictor is not
+  // constructed in this function).
+  template <class TransformT, class MeshDataT>
+  struct DispatchFunctor<TransformT, MeshDataT,
+                         PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON_CANONICALIZED> {
+    std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>> operator()(
+        PredictionSchemeMethod method, const PointAttribute *attribute,
+        const TransformT &transform, const MeshDataT &mesh_data,
+        uint16_t bitstream_version) {
+      if (method == MESH_PREDICTION_GEOMETRIC_NORMAL) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeGeometricNormalDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+      return nullptr;
+    }
+  };
+  template <class TransformT, class MeshDataT>
+  struct DispatchFunctor<TransformT, MeshDataT,
+                         PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON> {
+    std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>> operator()(
+        PredictionSchemeMethod method, const PointAttribute *attribute,
+        const TransformT &transform, const MeshDataT &mesh_data,
+        uint16_t bitstream_version) {
+      if (method == MESH_PREDICTION_GEOMETRIC_NORMAL) {
+        return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+            new MeshPredictionSchemeGeometricNormalDecoder<
+                DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                  mesh_data));
+      }
+      return nullptr;
+    }
+  };
+#endif
+
+  template <class TransformT, class MeshDataT>
+  std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>> operator()(
+      PredictionSchemeMethod method, const PointAttribute *attribute,
+      const TransformT &transform, const MeshDataT &mesh_data,
+      uint16_t bitstream_version) {
+    return DispatchFunctor<TransformT, MeshDataT, TransformT::GetType()>()(
+        method, attribute, transform, mesh_data, bitstream_version);
+  }
+};
+
+// Creates a prediction scheme for a given decoder and given prediction method.
+// The prediction schemes are automatically initialized with decoder specific
+// data if needed.
+template <typename DataTypeT, class TransformT>
+std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>
+CreatePredictionSchemeForDecoder(PredictionSchemeMethod method, int att_id,
+                                 const PointCloudDecoder *decoder,
+                                 const TransformT &transform) {
+  if (method == PREDICTION_NONE) {
+    return nullptr;
+  }
+  const PointAttribute *const att = decoder->point_cloud()->attribute(att_id);
+  if (decoder->GetGeometryType() == TRIANGULAR_MESH) {
+    // Cast the decoder to mesh decoder. This is not necessarily safe if there
+    // is some other decoder decides to use TRIANGULAR_MESH as the return type,
+    // but unfortunately there is not nice work around for this without using
+    // RTTI (double dispatch and similar concepts will not work because of the
+    // template nature of the prediction schemes).
+    const MeshDecoder *const mesh_decoder =
+        static_cast<const MeshDecoder *>(decoder);
+
+    auto ret = CreateMeshPredictionScheme<
+        MeshDecoder, PredictionSchemeDecoder<DataTypeT, TransformT>,
+        MeshPredictionSchemeDecoderFactory<DataTypeT>>(
+        mesh_decoder, method, att_id, transform, decoder->bitstream_version());
+    if (ret) {
+      return ret;
+    }
+    // Otherwise try to create another prediction scheme.
+  }
+  // Create delta decoder.
+  return std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>(
+      new PredictionSchemeDeltaDecoder<DataTypeT, TransformT>(att, transform));
+}
+
+// Create a prediction scheme using a default transform constructor.
+template <typename DataTypeT, class TransformT>
+std::unique_ptr<PredictionSchemeDecoder<DataTypeT, TransformT>>
+CreatePredictionSchemeForDecoder(PredictionSchemeMethod method, int att_id,
+                                 const PointCloudDecoder *decoder) {
+  return CreatePredictionSchemeForDecoder<DataTypeT, TransformT>(
+      method, att_id, decoder, TransformT());
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_FACTORY_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_decoder_interface.h

@@ -0,0 +1,53 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_INTERFACE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_INTERFACE_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_interface.h"
+#include "draco/core/decoder_buffer.h"
+
+// Prediction schemes can be used during encoding and decoding of attributes
+// to predict attribute values based on the previously encoded/decoded data.
+// See prediction_scheme.h for more details.
+namespace draco {
+
+// Abstract interface for all prediction schemes used during attribute encoding.
+class PredictionSchemeDecoderInterface : public PredictionSchemeInterface {
+ public:
+  // Method that can be used to decode any prediction scheme specific data
+  // from the input buffer.
+  virtual bool DecodePredictionData(DecoderBuffer *buffer) = 0;
+};
+
+// A specialized version of the prediction scheme interface for specific
+// input and output data types.
+// |entry_to_point_id_map| is the mapping between value entries to point ids
+// of the associated point cloud, where one entry is defined as |num_components|
+// values of the |in_data|.
+// DataTypeT is the data type of input and predicted values.
+// CorrTypeT is the data type used for storing corrected values.
+template <typename DataTypeT, typename CorrTypeT = DataTypeT>
+class PredictionSchemeTypedDecoderInterface
+    : public PredictionSchemeDecoderInterface {
+ public:
+  // Reverts changes made by the prediction scheme during encoding.
+  virtual bool ComputeOriginalValues(
+      const CorrTypeT *in_corr, DataTypeT *out_data, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) = 0;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODER_INTERFACE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_decoding_transform.h

@@ -0,0 +1,65 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODING_TRANSFORM_H_
+
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/decoder_buffer.h"
+
+namespace draco {
+
+// PredictionSchemeDecodingTransform is used to transform predicted values and
+// correction values into the final original attribute values.
+// DataTypeT is the data type of predicted values.
+// CorrTypeT is the data type used for storing corrected values. It allows
+// transforms to store corrections into a different type or format compared to
+// the predicted data.
+template <typename DataTypeT, typename CorrTypeT>
+class PredictionSchemeDecodingTransform {
+ public:
+  typedef CorrTypeT CorrType;
+  PredictionSchemeDecodingTransform() : num_components_(0) {}
+
+  void Init(int num_components) { num_components_ = num_components; }
+
+  // Computes the original value from the input predicted value and the decoded
+  // corrections. The default implementation is equal to std:plus.
+  inline void ComputeOriginalValue(const DataTypeT *predicted_vals,
+                                   const CorrTypeT *corr_vals,
+                                   DataTypeT *out_original_vals) const {
+    static_assert(std::is_same<DataTypeT, CorrTypeT>::value,
+                  "For the default prediction transform, correction and input "
+                  "data must be of the same type.");
+    for (int i = 0; i < num_components_; ++i) {
+      out_original_vals[i] = predicted_vals[i] + corr_vals[i];
+    }
+  }
+
+  // Decodes any transform specific data. Called before Init() method.
+  bool DecodeTransformData(DecoderBuffer * /* buffer */) { return true; }
+
+  // Should return true if all corrected values are guaranteed to be positive.
+  bool AreCorrectionsPositive() const { return false; }
+
+ protected:
+  int num_components() const { return num_components_; }
+
+ private:
+  int num_components_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DECODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_delta_decoder.h

@@ -0,0 +1,65 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder.h"
+
+namespace draco {
+
+// Decoder for values encoded with delta coding. See the corresponding encoder
+// for more details.
+template <typename DataTypeT, class TransformT>
+class PredictionSchemeDeltaDecoder
+    : public PredictionSchemeDecoder<DataTypeT, TransformT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeDecoder<DataTypeT, TransformT>::CorrType;
+  // Initialized the prediction scheme.
+  explicit PredictionSchemeDeltaDecoder(const PointAttribute *attribute)
+      : PredictionSchemeDecoder<DataTypeT, TransformT>(attribute) {}
+  PredictionSchemeDeltaDecoder(const PointAttribute *attribute,
+                               const TransformT &transform)
+      : PredictionSchemeDecoder<DataTypeT, TransformT>(attribute, transform) {}
+
+  bool ComputeOriginalValues(const CorrType *in_corr, DataTypeT *out_data,
+                             int size, int num_components,
+                             const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return PREDICTION_DIFFERENCE;
+  }
+  bool IsInitialized() const override { return true; }
+};
+
+template <typename DataTypeT, class TransformT>
+bool PredictionSchemeDeltaDecoder<DataTypeT, TransformT>::ComputeOriginalValues(
+    const CorrType *in_corr, DataTypeT *out_data, int size, int num_components,
+    const PointIndex *) {
+  this->transform().Init(num_components);
+  // Decode the original value for the first element.
+  std::unique_ptr<DataTypeT[]> zero_vals(new DataTypeT[num_components]());
+  this->transform().ComputeOriginalValue(zero_vals.get(), in_corr, out_data);
+
+  // Decode data from the front using D(i) = D(i) + D(i - 1).
+  for (int i = num_components; i < size; i += num_components) {
+    this->transform().ComputeOriginalValue(out_data + i - num_components,
+                                           in_corr + i, out_data + i);
+  }
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_delta_encoder.h

@@ -0,0 +1,69 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder.h"
+
+namespace draco {
+
+// Basic prediction scheme based on computing backward differences between
+// stored attribute values (also known as delta-coding). Usually works better
+// than the reference point prediction scheme, because nearby values are often
+// encoded next to each other.
+template <typename DataTypeT, class TransformT>
+class PredictionSchemeDeltaEncoder
+    : public PredictionSchemeEncoder<DataTypeT, TransformT> {
+ public:
+  using CorrType =
+      typename PredictionSchemeEncoder<DataTypeT, TransformT>::CorrType;
+  // Initialized the prediction scheme.
+  explicit PredictionSchemeDeltaEncoder(const PointAttribute *attribute)
+      : PredictionSchemeEncoder<DataTypeT, TransformT>(attribute) {}
+  PredictionSchemeDeltaEncoder(const PointAttribute *attribute,
+                               const TransformT &transform)
+      : PredictionSchemeEncoder<DataTypeT, TransformT>(attribute, transform) {}
+
+  bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrType *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) override;
+  PredictionSchemeMethod GetPredictionMethod() const override {
+    return PREDICTION_DIFFERENCE;
+  }
+  bool IsInitialized() const override { return true; }
+};
+
+template <typename DataTypeT, class TransformT>
+bool PredictionSchemeDeltaEncoder<
+    DataTypeT, TransformT>::ComputeCorrectionValues(const DataTypeT *in_data,
+                                                    CorrType *out_corr,
+                                                    int size,
+                                                    int num_components,
+                                                    const PointIndex *) {
+  this->transform().Init(in_data, size, num_components);
+  // Encode data from the back using D(i) = D(i) - D(i - 1).
+  for (int i = size - num_components; i > 0; i -= num_components) {
+    this->transform().ComputeCorrection(
+        in_data + i, in_data + i - num_components, out_corr + i);
+  }
+  // Encode correction for the first element.
+  std::unique_ptr<DataTypeT[]> zero_vals(new DataTypeT[num_components]());
+  this->transform().ComputeCorrection(in_data, zero_vals.get(), out_corr);
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_DELTA_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_encoder.h

@@ -0,0 +1,90 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_H_
+
+#include <type_traits>
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_interface.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoding_transform.h"
+
+// Prediction schemes can be used during encoding and decoding of vertex
+// attributes to predict attribute values based on the previously
+// encoded/decoded data. The differences between the original and predicted
+// attribute values are used to compute correction values that can be usually
+// encoded with fewer bits compared to the original data.
+namespace draco {
+
+// Abstract base class for typed prediction schemes. It provides basic access
+// to the encoded attribute and to the supplied prediction transform.
+template <typename DataTypeT,
+          class TransformT =
+              PredictionSchemeEncodingTransform<DataTypeT, DataTypeT>>
+class PredictionSchemeEncoder : public PredictionSchemeTypedEncoderInterface<
+                                    DataTypeT, typename TransformT::CorrType> {
+ public:
+  typedef DataTypeT DataType;
+  typedef TransformT Transform;
+  // Correction type needs to be defined in the prediction transform class.
+  typedef typename Transform::CorrType CorrType;
+  explicit PredictionSchemeEncoder(const PointAttribute *attribute)
+      : PredictionSchemeEncoder(attribute, Transform()) {}
+  PredictionSchemeEncoder(const PointAttribute *attribute,
+                          const Transform &transform)
+      : attribute_(attribute), transform_(transform) {}
+
+  bool EncodePredictionData(EncoderBuffer *buffer) override {
+    if (!transform_.EncodeTransformData(buffer)) {
+      return false;
+    }
+    return true;
+  }
+
+  const PointAttribute *GetAttribute() const override { return attribute(); }
+
+  // Returns the number of parent attributes that are needed for the prediction.
+  int GetNumParentAttributes() const override { return 0; }
+
+  // Returns the type of each of the parent attribute.
+  GeometryAttribute::Type GetParentAttributeType(int /* i */) const override {
+    return GeometryAttribute::INVALID;
+  }
+
+  // Sets the required parent attribute.
+  bool SetParentAttribute(const PointAttribute * /* att */) override {
+    return false;
+  }
+
+  bool AreCorrectionsPositive() override {
+    return transform_.AreCorrectionsPositive();
+  }
+
+  PredictionSchemeTransformType GetTransformType() const override {
+    return transform_.GetType();
+  }
+
+ protected:
+  inline const PointAttribute *attribute() const { return attribute_; }
+  inline const Transform &transform() const { return transform_; }
+  inline Transform &transform() { return transform_; }
+
+ private:
+  const PointAttribute *attribute_;
+  Transform transform_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.cc

@@ -0,0 +1,85 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.h"
+
+namespace draco {
+
+PredictionSchemeMethod SelectPredictionMethod(
+    int att_id, const PointCloudEncoder *encoder) {
+  if (encoder->options()->GetSpeed() >= 10) {
+    // Selected fastest, though still doing some compression.
+    return PREDICTION_DIFFERENCE;
+  }
+  if (encoder->GetGeometryType() == TRIANGULAR_MESH) {
+    // Use speed setting to select the best encoding method.
+    const PointAttribute *const att = encoder->point_cloud()->attribute(att_id);
+    if (att->attribute_type() == GeometryAttribute::TEX_COORD) {
+      if (encoder->options()->GetSpeed() < 4) {
+        // Use texture coordinate prediction for speeds 0, 1, 2, 3.
+        return MESH_PREDICTION_TEX_COORDS_PORTABLE;
+      }
+    }
+    if (att->attribute_type() == GeometryAttribute::NORMAL) {
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+      if (encoder->options()->GetSpeed() < 4) {
+        // Use geometric normal prediction for speeds 0, 1, 2, 3.
+        // For this prediction, the position attribute needs to be either
+        // integer or quantized as well.
+        const int pos_att_id = encoder->point_cloud()->GetNamedAttributeId(
+            GeometryAttribute::POSITION);
+        const PointAttribute *const pos_att =
+            encoder->point_cloud()->GetNamedAttribute(
+                GeometryAttribute::POSITION);
+        if (pos_att && (IsDataTypeIntegral(pos_att->data_type()) ||
+                        encoder->options()->GetAttributeInt(
+                            pos_att_id, "quantization_bits", -1) > 0)) {
+          return MESH_PREDICTION_GEOMETRIC_NORMAL;
+        }
+      }
+#endif
+      return PREDICTION_DIFFERENCE;  // default
+    }
+    // Handle other attribute types.
+    if (encoder->options()->GetSpeed() >= 8) {
+      return PREDICTION_DIFFERENCE;
+    }
+    if (encoder->options()->GetSpeed() >= 2 ||
+        encoder->point_cloud()->num_points() < 40) {
+      // Parallelogram prediction is used for speeds 2 - 7 or when the overhead
+      // of using constrained multi-parallelogram would be too high.
+      return MESH_PREDICTION_PARALLELOGRAM;
+    }
+    // Multi-parallelogram is used for speeds 0, 1.
+    return MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM;
+  }
+  // Default option is delta coding.
+  return PREDICTION_DIFFERENCE;
+}
+
+// Returns the preferred prediction scheme based on the encoder options.
+PredictionSchemeMethod GetPredictionMethodFromOptions(
+    int att_id, const EncoderOptions &options) {
+  const int pred_type =
+      options.GetAttributeInt(att_id, "prediction_scheme", -1);
+  if (pred_type == -1) {
+    return PREDICTION_UNDEFINED;
+  }
+  if (pred_type < 0 || pred_type >= NUM_PREDICTION_SCHEMES) {
+    return PREDICTION_NONE;
+  }
+  return static_cast<PredictionSchemeMethod>(pred_type);
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.h

@@ -0,0 +1,129 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Functions for creating prediction schemes for encoders using the provided
+// prediction method id.
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_FACTORY_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_FACTORY_H_
+
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_constrained_multi_parallelogram_encoder.h"
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_geometric_normal_encoder.h"
+#endif
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_multi_parallelogram_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_parallelogram_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_tex_coords_portable_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_delta_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_factory.h"
+#include "draco/compression/mesh/mesh_encoder.h"
+
+namespace draco {
+
+// Selects a prediction method based on the input geometry type and based on the
+// encoder options.
+PredictionSchemeMethod SelectPredictionMethod(int att_id,
+                                              const PointCloudEncoder *encoder);
+
+// Factory class for creating mesh prediction schemes.
+template <typename DataTypeT>
+struct MeshPredictionSchemeEncoderFactory {
+  template <class TransformT, class MeshDataT>
+  std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>> operator()(
+      PredictionSchemeMethod method, const PointAttribute *attribute,
+      const TransformT &transform, const MeshDataT &mesh_data,
+      uint16_t bitstream_version) {
+    if (method == MESH_PREDICTION_PARALLELOGRAM) {
+      return std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>(
+          new MeshPredictionSchemeParallelogramEncoder<DataTypeT, TransformT,
+                                                       MeshDataT>(
+              attribute, transform, mesh_data));
+    } else if (method == MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM) {
+      return std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>(
+          new MeshPredictionSchemeConstrainedMultiParallelogramEncoder<
+              DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                mesh_data));
+    } else if (method == MESH_PREDICTION_TEX_COORDS_PORTABLE) {
+      return std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>(
+          new MeshPredictionSchemeTexCoordsPortableEncoder<
+              DataTypeT, TransformT, MeshDataT>(attribute, transform,
+                                                mesh_data));
+    }
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+    else if (method == MESH_PREDICTION_GEOMETRIC_NORMAL) {
+      return std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>(
+          new MeshPredictionSchemeGeometricNormalEncoder<DataTypeT, TransformT,
+                                                         MeshDataT>(
+              attribute, transform, mesh_data));
+    }
+#endif
+    return nullptr;
+  }
+};
+
+// Creates a prediction scheme for a given encoder and given prediction method.
+// The prediction schemes are automatically initialized with encoder specific
+// data if needed.
+template <typename DataTypeT, class TransformT>
+std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>
+CreatePredictionSchemeForEncoder(PredictionSchemeMethod method, int att_id,
+                                 const PointCloudEncoder *encoder,
+                                 const TransformT &transform) {
+  const PointAttribute *const att = encoder->point_cloud()->attribute(att_id);
+  if (method == PREDICTION_UNDEFINED) {
+    method = SelectPredictionMethod(att_id, encoder);
+  }
+  if (method == PREDICTION_NONE) {
+    return nullptr;  // No prediction is used.
+  }
+  if (encoder->GetGeometryType() == TRIANGULAR_MESH) {
+    // Cast the encoder to mesh encoder. This is not necessarily safe if there
+    // is some other encoder decides to use TRIANGULAR_MESH as the return type,
+    // but unfortunately there is not nice work around for this without using
+    // RTTI (double dispatch and similar concepts will not work because of the
+    // template nature of the prediction schemes).
+    const MeshEncoder *const mesh_encoder =
+        static_cast<const MeshEncoder *>(encoder);
+    auto ret = CreateMeshPredictionScheme<
+        MeshEncoder, PredictionSchemeEncoder<DataTypeT, TransformT>,
+        MeshPredictionSchemeEncoderFactory<DataTypeT>>(
+        mesh_encoder, method, att_id, transform, kDracoMeshBitstreamVersion);
+    if (ret) {
+      return ret;
+    }
+    // Otherwise try to create another prediction scheme.
+  }
+  // Create delta encoder.
+  return std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>(
+      new PredictionSchemeDeltaEncoder<DataTypeT, TransformT>(att, transform));
+}
+
+// Create a prediction scheme using a default transform constructor.
+template <typename DataTypeT, class TransformT>
+std::unique_ptr<PredictionSchemeEncoder<DataTypeT, TransformT>>
+CreatePredictionSchemeForEncoder(PredictionSchemeMethod method, int att_id,
+                                 const PointCloudEncoder *encoder) {
+  return CreatePredictionSchemeForEncoder<DataTypeT, TransformT>(
+      method, att_id, encoder, TransformT());
+}
+
+// Returns the preferred prediction scheme based on the encoder options.
+PredictionSchemeMethod GetPredictionMethodFromOptions(
+    int att_id, const EncoderOptions &options);
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_FACTORY_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_interface.h

@@ -0,0 +1,55 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_INTERFACE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_INTERFACE_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_interface.h"
+#include "draco/core/encoder_buffer.h"
+
+// Prediction schemes can be used during encoding and decoding of attributes
+// to predict attribute values based on the previously encoded/decoded data.
+// See prediction_scheme.h for more details.
+namespace draco {
+
+// Abstract interface for all prediction schemes used during attribute encoding.
+class PredictionSchemeEncoderInterface : public PredictionSchemeInterface {
+ public:
+  // Method that can be used to encode any prediction scheme specific data
+  // into the output buffer.
+  virtual bool EncodePredictionData(EncoderBuffer *buffer) = 0;
+};
+
+// A specialized version of the prediction scheme interface for specific
+// input and output data types.
+// |entry_to_point_id_map| is the mapping between value entries to point ids
+// of the associated point cloud, where one entry is defined as |num_components|
+// values of the |in_data|.
+// DataTypeT is the data type of input and predicted values.
+// CorrTypeT is the data type used for storing corrected values.
+template <typename DataTypeT, typename CorrTypeT = DataTypeT>
+class PredictionSchemeTypedEncoderInterface
+    : public PredictionSchemeEncoderInterface {
+ public:
+  // Applies the prediction scheme when encoding the attribute.
+  // |in_data| contains value entries to be encoded.
+  // |out_corr| is an output array containing the to be encoded corrections.
+  virtual bool ComputeCorrectionValues(
+      const DataTypeT *in_data, CorrTypeT *out_corr, int size,
+      int num_components, const PointIndex *entry_to_point_id_map) = 0;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODER_INTERFACE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_encoding_transform.h

@@ -0,0 +1,77 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODING_TRANSFORM_H_
+
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/encoder_buffer.h"
+
+namespace draco {
+
+// PredictionSchemeEncodingTransform is used to transform predicted values into
+// correction values.
+// CorrTypeT is the data type used for storing corrected values. It allows
+// transforms to store corrections into a different type or format compared to
+// the predicted data.
+template <typename DataTypeT, typename CorrTypeT>
+class PredictionSchemeEncodingTransform {
+ public:
+  typedef CorrTypeT CorrType;
+  PredictionSchemeEncodingTransform() : num_components_(0) {}
+
+  PredictionSchemeTransformType GetType() const {
+    return PREDICTION_TRANSFORM_DELTA;
+  }
+
+  // Performs any custom initialization of the transform for the encoder.
+  // |size| = total number of values in |orig_data| (i.e., number of entries *
+  // number of components).
+  void Init(const DataTypeT * /* orig_data */, int /* size */,
+            int num_components) {
+    num_components_ = num_components;
+  }
+
+  // Computes the corrections based on the input original values and the
+  // predicted values. The correction is always computed for all components
+  // of the input element. |val_id| is the id of the input value
+  // (i.e., element_id * num_components). The default implementation is equal to
+  // std::minus.
+  inline void ComputeCorrection(const DataTypeT *original_vals,
+                                const DataTypeT *predicted_vals,
+                                CorrTypeT *out_corr_vals) {
+    static_assert(std::is_same<DataTypeT, CorrTypeT>::value,
+                  "For the default prediction transform, correction and input "
+                  "data must be of the same type.");
+    for (int i = 0; i < num_components_; ++i) {
+      out_corr_vals[i] = original_vals[i] - predicted_vals[i];
+    }
+  }
+
+  // Encode any transform specific data.
+  bool EncodeTransformData(EncoderBuffer * /* buffer */) { return true; }
+
+  // Should return true if all corrected values are guaranteed to be positive.
+  bool AreCorrectionsPositive() const { return false; }
+
+ protected:
+  int num_components() const { return num_components_; }
+
+ private:
+  int num_components_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_ENCODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_factory.h

@@ -0,0 +1,85 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Functions for creating prediction schemes from a provided prediction method
+// name. The functions in this file can create only basic prediction schemes
+// that don't require any encoder or decoder specific data. To create more
+// sophisticated prediction schemes, use functions from either
+// prediction_scheme_encoder_factory.h  or,
+// prediction_scheme_decoder_factory.h.
+
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_FACTORY_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_FACTORY_H_
+
+#include "draco/compression/attributes/mesh_attribute_indices_encoding_data.h"
+#include "draco/compression/attributes/prediction_schemes/mesh_prediction_scheme_data.h"
+#include "draco/compression/config/compression_shared.h"
+#include "draco/mesh/mesh_attribute_corner_table.h"
+
+namespace draco {
+
+template <class EncodingDataSourceT, class PredictionSchemeT,
+          class MeshPredictionSchemeFactoryT>
+std::unique_ptr<PredictionSchemeT> CreateMeshPredictionScheme(
+    const EncodingDataSourceT *source, PredictionSchemeMethod method,
+    int att_id, const typename PredictionSchemeT::Transform &transform,
+    uint16_t bitstream_version) {
+  const PointAttribute *const att = source->point_cloud()->attribute(att_id);
+  if (source->GetGeometryType() == TRIANGULAR_MESH &&
+      (method == MESH_PREDICTION_PARALLELOGRAM ||
+       method == MESH_PREDICTION_MULTI_PARALLELOGRAM ||
+       method == MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM ||
+       method == MESH_PREDICTION_TEX_COORDS_PORTABLE ||
+       method == MESH_PREDICTION_GEOMETRIC_NORMAL ||
+       method == MESH_PREDICTION_TEX_COORDS_DEPRECATED)) {
+    const CornerTable *const ct = source->GetCornerTable();
+    const MeshAttributeIndicesEncodingData *const encoding_data =
+        source->GetAttributeEncodingData(att_id);
+    if (ct == nullptr || encoding_data == nullptr) {
+      // No connectivity data found.
+      return nullptr;
+    }
+    // Connectivity data exists.
+    const MeshAttributeCornerTable *const att_ct =
+        source->GetAttributeCornerTable(att_id);
+    if (att_ct != nullptr) {
+      typedef MeshPredictionSchemeData<MeshAttributeCornerTable> MeshData;
+      MeshData md;
+      md.Set(source->mesh(), att_ct,
+             &encoding_data->encoded_attribute_value_index_to_corner_map,
+             &encoding_data->vertex_to_encoded_attribute_value_index_map);
+      MeshPredictionSchemeFactoryT factory;
+      auto ret = factory(method, att, transform, md, bitstream_version);
+      if (ret) {
+        return ret;
+      }
+    } else {
+      typedef MeshPredictionSchemeData<CornerTable> MeshData;
+      MeshData md;
+      md.Set(source->mesh(), ct,
+             &encoding_data->encoded_attribute_value_index_to_corner_map,
+             &encoding_data->vertex_to_encoded_attribute_value_index_map);
+      MeshPredictionSchemeFactoryT factory;
+      auto ret = factory(method, att, transform, md, bitstream_version);
+      if (ret) {
+        return ret;
+      }
+    }
+  }
+  return nullptr;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_FACTORY_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_interface.h

@@ -0,0 +1,60 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_INTERFACE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_INTERFACE_H_
+
+#include "draco/attributes/point_attribute.h"
+#include "draco/compression/config/compression_shared.h"
+
+// Prediction schemes can be used during encoding and decoding of attributes
+// to predict attribute values based on the previously encoded/decoded data.
+// See prediction_scheme.h for more details.
+namespace draco {
+
+// Abstract interface for all prediction schemes used during attribute encoding.
+class PredictionSchemeInterface {
+ public:
+  virtual ~PredictionSchemeInterface() = default;
+  virtual PredictionSchemeMethod GetPredictionMethod() const = 0;
+
+  // Returns the encoded attribute.
+  virtual const PointAttribute *GetAttribute() const = 0;
+
+  // Returns true when the prediction scheme is initialized with all data it
+  // needs.
+  virtual bool IsInitialized() const = 0;
+
+  // Returns the number of parent attributes that are needed for the prediction.
+  virtual int GetNumParentAttributes() const = 0;
+
+  // Returns the type of each of the parent attribute.
+  virtual GeometryAttribute::Type GetParentAttributeType(int i) const = 0;
+
+  // Sets the required parent attribute.
+  // Returns false if the attribute doesn't meet the requirements of the
+  // prediction scheme.
+  virtual bool SetParentAttribute(const PointAttribute *att) = 0;
+
+  // Method should return true if the prediction scheme guarantees that all
+  // correction values are always positive (or at least non-negative).
+  virtual bool AreCorrectionsPositive() = 0;
+
+  // Returns the transform type used by the prediction scheme.
+  virtual PredictionSchemeTransformType GetTransformType() const = 0;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_INTERFACE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_decoding_transform.h

@@ -0,0 +1,118 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_DECODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_DECODING_TRANSFORM_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_transform_base.h"
+#include "draco/core/decoder_buffer.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+
+namespace draco {
+
+// Class for converting correction values transformed by the canonicalized
+// normal octahedron transform back to the original values. See the
+// corresponding encoder for more details.
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronCanonicalizedDecodingTransform
+    : public PredictionSchemeNormalOctahedronCanonicalizedTransformBase<
+          DataTypeT> {
+ public:
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT CorrType;
+  typedef DataTypeT DataType;
+
+  PredictionSchemeNormalOctahedronCanonicalizedDecodingTransform() {}
+
+  // Dummy to fulfill concept.
+  void Init(int num_components) {}
+
+  bool DecodeTransformData(DecoderBuffer *buffer) {
+    DataTypeT max_quantized_value, center_value;
+    if (!buffer->Decode(&max_quantized_value)) {
+      return false;
+    }
+    if (!buffer->Decode(&center_value)) {
+      return false;
+    }
+    (void)center_value;
+    if (!this->set_max_quantized_value(max_quantized_value)) {
+      return false;
+    }
+    // Account for reading wrong values, e.g., due to fuzzing.
+    if (this->quantization_bits() < 2) {
+      return false;
+    }
+    if (this->quantization_bits() > 30) {
+      return false;
+    }
+    return true;
+  }
+
+  inline void ComputeOriginalValue(const DataType *pred_vals,
+                                   const CorrType *corr_vals,
+                                   DataType *out_orig_vals) const {
+    DRACO_DCHECK_LE(pred_vals[0], 2 * this->center_value());
+    DRACO_DCHECK_LE(pred_vals[1], 2 * this->center_value());
+    DRACO_DCHECK_LE(corr_vals[0], 2 * this->center_value());
+    DRACO_DCHECK_LE(corr_vals[1], 2 * this->center_value());
+
+    DRACO_DCHECK_LE(0, pred_vals[0]);
+    DRACO_DCHECK_LE(0, pred_vals[1]);
+    DRACO_DCHECK_LE(0, corr_vals[0]);
+    DRACO_DCHECK_LE(0, corr_vals[1]);
+
+    const Point2 pred = Point2(pred_vals[0], pred_vals[1]);
+    const Point2 corr = Point2(corr_vals[0], corr_vals[1]);
+    const Point2 orig = ComputeOriginalValue(pred, corr);
+
+    out_orig_vals[0] = orig[0];
+    out_orig_vals[1] = orig[1];
+  }
+
+ private:
+  Point2 ComputeOriginalValue(Point2 pred, Point2 corr) const {
+    const Point2 t(this->center_value(), this->center_value());
+    pred = pred - t;
+    const bool pred_is_in_diamond = this->IsInDiamond(pred[0], pred[1]);
+    if (!pred_is_in_diamond) {
+      this->InvertDiamond(&pred[0], &pred[1]);
+    }
+    const bool pred_is_in_bottom_left = this->IsInBottomLeft(pred);
+    const int32_t rotation_count = this->GetRotationCount(pred);
+    if (!pred_is_in_bottom_left) {
+      pred = this->RotatePoint(pred, rotation_count);
+    }
+    Point2 orig = pred + corr;
+    orig[0] = this->ModMax(orig[0]);
+    orig[1] = this->ModMax(orig[1]);
+    if (!pred_is_in_bottom_left) {
+      const int32_t reverse_rotation_count = (4 - rotation_count) % 4;
+      orig = this->RotatePoint(orig, reverse_rotation_count);
+    }
+    if (!pred_is_in_diamond) {
+      this->InvertDiamond(&orig[0], &orig[1]);
+    }
+    orig = orig + t;
+    return orig;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_DECODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_encoding_transform.h

@@ -0,0 +1,116 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_ENCODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_ENCODING_TRANSFORM_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_transform_base.h"
+#include "draco/core/encoder_buffer.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+
+namespace draco {
+
+// The transform works on octahedral coordinates for normals. The square is
+// subdivided into four inner triangles (diamond) and four outer triangles. The
+// inner triangles are associated with the upper part of the octahedron and the
+// outer triangles are associated with the lower part.
+// Given a prediction value P and the actual value Q that should be encoded,
+// this transform first checks if P is outside the diamond. If so, the outer
+// triangles are flipped towards the inside and vice versa. Then it checks if p
+// is in the bottom left quadrant. If it is not, it rotates p and q accordingly.
+// The actual correction value is then based on the mapped and rotated P and Q
+// values. The inversion tends to result in shorter correction vectors and the
+// rotation makes it so that all long correction values are positive, reducing
+// the possible value range of the correction values and increasing the
+// occurrences of positive large correction values, which helps the entropy
+// encoder. This is possible since P is also known by the decoder, see also
+// ComputeCorrection and ComputeOriginalValue functions.
+// Note that the tile is not periodic, which implies that the outer edges can
+// not be identified, which requires us to use an odd number of values on each
+// axis.
+// DataTypeT is expected to be some integral type.
+//
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronCanonicalizedEncodingTransform
+    : public PredictionSchemeNormalOctahedronCanonicalizedTransformBase<
+          DataTypeT> {
+ public:
+  typedef PredictionSchemeNormalOctahedronCanonicalizedTransformBase<DataTypeT>
+      Base;
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT CorrType;
+  typedef DataTypeT DataType;
+
+  // We expect the mod value to be of the form 2^b-1.
+  explicit PredictionSchemeNormalOctahedronCanonicalizedEncodingTransform(
+      DataType max_quantized_value)
+      : Base(max_quantized_value) {}
+
+  // Dummy function to fulfill concept.
+  void Init(const DataTypeT *orig_data, int size, int num_components) {}
+
+  bool EncodeTransformData(EncoderBuffer *buffer) {
+    buffer->Encode(this->max_quantized_value());
+    buffer->Encode(this->center_value());
+    return true;
+  }
+
+  inline void ComputeCorrection(const DataType *orig_vals,
+                                const DataType *pred_vals,
+                                CorrType *out_corr_vals) const {
+    DRACO_DCHECK_LE(pred_vals[0], this->center_value() * 2);
+    DRACO_DCHECK_LE(pred_vals[1], this->center_value() * 2);
+    DRACO_DCHECK_LE(orig_vals[0], this->center_value() * 2);
+    DRACO_DCHECK_LE(orig_vals[1], this->center_value() * 2);
+    DRACO_DCHECK_LE(0, pred_vals[0]);
+    DRACO_DCHECK_LE(0, pred_vals[1]);
+    DRACO_DCHECK_LE(0, orig_vals[0]);
+    DRACO_DCHECK_LE(0, orig_vals[1]);
+
+    const Point2 orig = Point2(orig_vals[0], orig_vals[1]);
+    const Point2 pred = Point2(pred_vals[0], pred_vals[1]);
+    const Point2 corr = ComputeCorrection(orig, pred);
+
+    out_corr_vals[0] = corr[0];
+    out_corr_vals[1] = corr[1];
+  }
+
+ private:
+  Point2 ComputeCorrection(Point2 orig, Point2 pred) const {
+    const Point2 t(this->center_value(), this->center_value());
+    orig = orig - t;
+    pred = pred - t;
+    if (!this->IsInDiamond(pred[0], pred[1])) {
+      this->InvertDiamond(&orig[0], &orig[1]);
+      this->InvertDiamond(&pred[0], &pred[1]);
+    }
+    if (!this->IsInBottomLeft(pred)) {
+      const int32_t rotation_count = this->GetRotationCount(pred);
+      orig = this->RotatePoint(orig, rotation_count);
+      pred = this->RotatePoint(pred, rotation_count);
+    }
+    Point2 corr = orig - pred;
+    corr[0] = this->MakePositive(corr[0]);
+    corr[1] = this->MakePositive(corr[1]);
+    return corr;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_ENCODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_transform_base.h

@@ -0,0 +1,102 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_TRANSFORM_BASE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_TRANSFORM_BASE_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_transform_base.h"
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/bit_utils.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+
+namespace draco {
+
+// Base class containing shared functionality used by both encoding and decoding
+// canonicalized normal octahedron prediction scheme transforms. See the
+// encoding transform for more details about the method.
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronCanonicalizedTransformBase
+    : public PredictionSchemeNormalOctahedronTransformBase<DataTypeT> {
+ public:
+  typedef PredictionSchemeNormalOctahedronTransformBase<DataTypeT> Base;
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT DataType;
+
+  PredictionSchemeNormalOctahedronCanonicalizedTransformBase() : Base() {}
+  // We expect the mod value to be of the form 2^b-1.
+  explicit PredictionSchemeNormalOctahedronCanonicalizedTransformBase(
+      DataType mod_value)
+      : Base(mod_value) {}
+
+  static constexpr PredictionSchemeTransformType GetType() {
+    return PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON_CANONICALIZED;
+  }
+
+  int32_t GetRotationCount(Point2 pred) const {
+    const DataType sign_x = pred[0];
+    const DataType sign_y = pred[1];
+
+    int32_t rotation_count = 0;
+    if (sign_x == 0) {
+      if (sign_y == 0) {
+        rotation_count = 0;
+      } else if (sign_y > 0) {
+        rotation_count = 3;
+      } else {
+        rotation_count = 1;
+      }
+    } else if (sign_x > 0) {
+      if (sign_y >= 0) {
+        rotation_count = 2;
+      } else {
+        rotation_count = 1;
+      }
+    } else {
+      if (sign_y <= 0) {
+        rotation_count = 0;
+      } else {
+        rotation_count = 3;
+      }
+    }
+    return rotation_count;
+  }
+
+  Point2 RotatePoint(Point2 p, int32_t rotation_count) const {
+    switch (rotation_count) {
+      case 1:
+        return Point2(p[1], -p[0]);
+      case 2:
+        return Point2(-p[0], -p[1]);
+      case 3:
+        return Point2(-p[1], p[0]);
+      default:
+        return p;
+    }
+  }
+
+  bool IsInBottomLeft(const Point2 &p) const {
+    if (p[0] == 0 && p[1] == 0) {
+      return true;
+    }
+    return (p[0] < 0 && p[1] <= 0);
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_CANONICALIZED_TRANSFORM_BASE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_transform_test.cc

@@ -0,0 +1,192 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_encoding_transform.h"
+#include "draco/core/draco_test_base.h"
+
+namespace {
+
+class PredictionSchemeNormalOctahedronCanonicalizedTransformTest
+    : public ::testing::Test {
+ protected:
+  typedef draco::PredictionSchemeNormalOctahedronCanonicalizedEncodingTransform<
+      int32_t>
+      Transform;
+  typedef Transform::Point2 Point2;
+
+  void TestComputeCorrection(const Transform &transform, const int32_t &ox,
+                             const int32_t &oy, const int32_t &px,
+                             const int32_t &py, const int32_t &cx,
+                             const int32_t &cy) {
+    const int32_t o[2] = {ox + 7, oy + 7};
+    const int32_t p[2] = {px + 7, py + 7};
+    int32_t corr[2] = {500, 500};
+    transform.ComputeCorrection(o, p, corr);
+    ASSERT_EQ(corr[0], (cx + 15) % 15);
+    ASSERT_EQ(corr[1], (cy + 15) % 15);
+  }
+
+  void TestGetRotationCount(const Transform &transform, const Point2 &pred,
+                            const int32_t &rot_dir) {
+    const int32_t rotation_count = transform.GetRotationCount(pred);
+    ASSERT_EQ(rot_dir, rotation_count);
+  }
+
+  void TestRotateRepresentation(const Transform &transform, const Point2 &org,
+                                const Point2 &pred, const Point2 &rot_org,
+                                const Point2 &rot_pred) {
+    const int32_t rotation_count = transform.GetRotationCount(pred);
+    const Point2 res_org = transform.RotatePoint(org, rotation_count);
+    const Point2 res_pred = transform.RotatePoint(pred, rotation_count);
+    ASSERT_EQ(rot_org[0], res_org[0]);
+    ASSERT_EQ(rot_org[1], res_org[1]);
+    ASSERT_EQ(rot_pred[0], res_pred[0]);
+    ASSERT_EQ(rot_pred[1], res_pred[1]);
+  }
+};
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest, Init) {
+  const Transform transform(15);
+  ASSERT_TRUE(transform.AreCorrectionsPositive());
+}
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest,
+       IsInBottomLeft) {
+  const Transform transform(15);
+  ASSERT_TRUE(transform.IsInBottomLeft(Point2(0, 0)));
+  ASSERT_TRUE(transform.IsInBottomLeft(Point2(-1, -1)));
+  ASSERT_TRUE(transform.IsInBottomLeft(Point2(-7, -7)));
+
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(1, 1)));
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(7, 7)));
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(-1, 1)));
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(-7, 7)));
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(1, -1)));
+  ASSERT_FALSE(transform.IsInBottomLeft(Point2(7, -7)));
+}
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest,
+       GetRotationCount) {
+  const Transform transform(15);
+  TestGetRotationCount(transform, Point2(1, 2), 2);    // top right
+  TestGetRotationCount(transform, Point2(-1, 2), 3);   // top left
+  TestGetRotationCount(transform, Point2(1, -2), 1);   // bottom right
+  TestGetRotationCount(transform, Point2(-1, -2), 0);  // bottom left
+  TestGetRotationCount(transform, Point2(0, 2), 3);    // top left
+  TestGetRotationCount(transform, Point2(0, -2), 1);   // bottom right
+  TestGetRotationCount(transform, Point2(2, 0), 2);    // top right
+  TestGetRotationCount(transform, Point2(-2, 0), 0);   // bottom left
+  TestGetRotationCount(transform, Point2(0, 0), 0);    // bottom left
+}
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest,
+       RotateRepresentation) {
+  const Transform transform(15);
+  // p top left; shift clockwise by 3
+  TestRotateRepresentation(transform, Point2(1, 2), Point2(-3, 1),
+                           Point2(-2, 1), Point2(-1, -3));  // q top right
+  TestRotateRepresentation(transform, Point2(-1, -2), Point2(-3, 1),
+                           Point2(2, -1), Point2(-1, -3));  // q bottom left
+  TestRotateRepresentation(transform, Point2(1, -2), Point2(-3, 1),
+                           Point2(2, 1), Point2(-1, -3));  // q bottom right
+  TestRotateRepresentation(transform, Point2(-1, 2), Point2(-3, 1),
+                           Point2(-2, -1), Point2(-1, -3));  // q top left
+  // p top right; shift clockwise by 2 (flip)
+  TestRotateRepresentation(transform, Point2(1, 1), Point2(1, 3),
+                           Point2(-1, -1), Point2(-1, -3));  // q top right
+  TestRotateRepresentation(transform, Point2(-1, -2), Point2(1, 3),
+                           Point2(1, 2), Point2(-1, -3));  // q bottom left
+  TestRotateRepresentation(transform, Point2(-1, 2), Point2(1, 3),
+                           Point2(1, -2), Point2(-1, -3));  // q top left
+  TestRotateRepresentation(transform, Point2(1, -2), Point2(1, 3),
+                           Point2(-1, 2), Point2(-1, -3));  // q bottom right
+  // p bottom right; shift clockwise by 1
+  TestRotateRepresentation(transform, Point2(1, 2), Point2(3, -1),
+                           Point2(2, -1), Point2(-1, -3));  // q top right
+  TestRotateRepresentation(transform, Point2(1, -2), Point2(3, -1),
+                           Point2(-2, -1), Point2(-1, -3));  // q bottom right
+  TestRotateRepresentation(transform, Point2(-1, -2), Point2(3, -1),
+                           Point2(-2, 1), Point2(-1, -3));  // q bottom left
+  TestRotateRepresentation(transform, Point2(-1, 2), Point2(3, -1),
+                           Point2(2, 1), Point2(-1, -3));  // q top left
+  // p bottom left; no change
+  TestRotateRepresentation(transform, Point2(1, 2), Point2(-1, -3),
+                           Point2(1, 2), Point2(-1, -3));  // q top right
+  TestRotateRepresentation(transform, Point2(-1, 2), Point2(-1, -3),
+                           Point2(-1, 2), Point2(-1, -3));  // q top left
+  TestRotateRepresentation(transform, Point2(1, -2), Point2(-1, -3),
+                           Point2(1, -2), Point2(-1, -3));  // q bottom right
+  TestRotateRepresentation(transform, Point2(-1, -2), Point2(-1, -3),
+                           Point2(-1, -2), Point2(-1, -3));  // q bottom left
+}
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest,
+       ComputeCorrection) {
+  const Transform transform(15);
+  TestComputeCorrection(transform, 0, 0, 0, 0, 0, 0);
+  TestComputeCorrection(transform, 1, 1, 1, 1, 0, 0);
+  // inside diamond; p top right
+  TestComputeCorrection(transform, 3, 4, 1, 2, -2, -2);  // q top right
+  TestComputeCorrection(transform, -3, 4, 1, 2, 4, -2);  // q top left
+  TestComputeCorrection(transform, 3, -4, 1, 2, -2, 6);  // q bottom right
+  TestComputeCorrection(transform, -3, -4, 1, 2, 4, 6);  // q bottom left
+  // inside diamond; p top left
+  TestComputeCorrection(transform, 3, 4, -1, 2, -2, 4);    // q top right
+  TestComputeCorrection(transform, -3, 4, -1, 2, -2, -2);  // q top left
+  TestComputeCorrection(transform, 3, -4, -1, 2, 6, 4);    // q bottom right
+  TestComputeCorrection(transform, -3, -4, -1, 2, 6, -2);  // q bottom left
+  // inside diamond; p bottom right
+  TestComputeCorrection(transform, 3, 4, 1, -2, 6, -2);    // q top right
+  TestComputeCorrection(transform, -3, 4, 1, -2, 6, 4);    // q top left
+  TestComputeCorrection(transform, 3, -4, 1, -2, -2, -2);  // q bottom right
+  TestComputeCorrection(transform, -3, -4, 1, -2, -2, 4);  // q bottom left
+  // inside diamond; p bottom left
+  TestComputeCorrection(transform, 3, 4, -1, -2, 4, 6);      // q top right
+  TestComputeCorrection(transform, -3, 4, -1, -2, -2, 6);    // q top left
+  TestComputeCorrection(transform, 3, -4, -1, -2, 4, -2);    // q bottom right
+  TestComputeCorrection(transform, -3, -4, -1, -2, -2, -2);  // q bottom left
+  // outside diamond; p top right
+  TestComputeCorrection(transform, 1, 2, 5, 4, -2, -4);    // q top right
+  TestComputeCorrection(transform, -1, 2, 5, 4, -7, -4);   // q top left
+  TestComputeCorrection(transform, 1, -2, 5, 4, -2, -7);   // q bottom right
+  TestComputeCorrection(transform, -1, -2, 5, 4, -7, -7);  // q bottom left
+  // outside diamond; p top left
+  TestComputeCorrection(transform, 1, 2, -5, 4, -4, -7);    // q top right
+  TestComputeCorrection(transform, -1, 2, -5, 4, -4, -2);   // q top left
+  TestComputeCorrection(transform, 1, -2, -5, 4, -7, -7);   // q bottom right
+  TestComputeCorrection(transform, -1, -2, -5, 4, -7, -2);  // q bottom left
+  // outside diamond; p bottom right
+  TestComputeCorrection(transform, 1, 2, 5, -4, -7, -2);    // q top right
+  TestComputeCorrection(transform, -1, 2, 5, -4, -7, -7);   // q top left
+  TestComputeCorrection(transform, 1, -2, 5, -4, -4, -2);   // q bottom right
+  TestComputeCorrection(transform, -1, -2, 5, -4, -4, -7);  // q bottom left
+  // outside diamond; p bottom left
+  TestComputeCorrection(transform, 1, 2, -5, -4, -7, -7);    // q top right
+  TestComputeCorrection(transform, -1, 2, -5, -4, -2, -7);   // q top left
+  TestComputeCorrection(transform, 1, -2, -5, -4, -7, -4);   // q bottom right
+  TestComputeCorrection(transform, -1, -2, -5, -4, -2, -4);  // q bottom left
+
+  TestComputeCorrection(transform, -1, -2, 7, 7, -5, -6);
+  TestComputeCorrection(transform, 0, 0, 7, 7, 7, 7);
+  TestComputeCorrection(transform, -1, -2, 0, -2, 0, 1);
+}
+
+TEST_F(PredictionSchemeNormalOctahedronCanonicalizedTransformTest, Interface) {
+  const Transform transform(15);
+  ASSERT_EQ(transform.max_quantized_value(), 15);
+  ASSERT_EQ(transform.center_value(), 7);
+  ASSERT_EQ(transform.quantization_bits(), 4);
+}
+
+}  // namespace

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_decoding_transform.h

@@ -0,0 +1,103 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_DECODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_DECODING_TRANSFORM_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_transform_base.h"
+#include "draco/core/decoder_buffer.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Class for converting correction values transformed by the octahedral normal
+// transform back to the original values. See the corresponding encoder for more
+// details.
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronDecodingTransform
+    : public PredictionSchemeNormalOctahedronTransformBase<DataTypeT> {
+ public:
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT CorrType;
+  typedef DataTypeT DataType;
+
+  PredictionSchemeNormalOctahedronDecodingTransform() {}
+
+  // Dummy function to fulfill concept.
+  void Init(int num_components) {}
+  bool DecodeTransformData(DecoderBuffer *buffer) {
+    DataTypeT max_quantized_value, center_value;
+    if (!buffer->Decode(&max_quantized_value)) {
+      return false;
+    }
+    if (buffer->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 2)) {
+      if (!buffer->Decode(&center_value)) {
+        return false;
+      }
+    }
+    (void)center_value;
+    return this->set_max_quantized_value(max_quantized_value);
+  }
+
+  inline void ComputeOriginalValue(const DataType *pred_vals,
+                                   const CorrType *corr_vals,
+                                   DataType *out_orig_vals) const {
+    DRACO_DCHECK_LE(pred_vals[0], 2 * this->center_value());
+    DRACO_DCHECK_LE(pred_vals[1], 2 * this->center_value());
+    DRACO_DCHECK_LE(corr_vals[0], 2 * this->center_value());
+    DRACO_DCHECK_LE(corr_vals[1], 2 * this->center_value());
+
+    DRACO_DCHECK_LE(0, pred_vals[0]);
+    DRACO_DCHECK_LE(0, pred_vals[1]);
+    DRACO_DCHECK_LE(0, corr_vals[0]);
+    DRACO_DCHECK_LE(0, corr_vals[1]);
+
+    const Point2 pred = Point2(pred_vals[0], pred_vals[1]);
+    const Point2 corr = Point2(corr_vals[0], corr_vals[1]);
+    const Point2 orig = ComputeOriginalValue(pred, corr);
+
+    out_orig_vals[0] = orig[0];
+    out_orig_vals[1] = orig[1];
+  }
+
+ private:
+  Point2 ComputeOriginalValue(Point2 pred, const Point2 &corr) const {
+    const Point2 t(this->center_value(), this->center_value());
+    pred = pred - t;
+
+    const bool pred_is_in_diamond = this->IsInDiamond(pred[0], pred[1]);
+    if (!pred_is_in_diamond) {
+      this->InvertDiamond(&pred[0], &pred[1]);
+    }
+    Point2 orig = pred + corr;
+    orig[0] = this->ModMax(orig[0]);
+    orig[1] = this->ModMax(orig[1]);
+    if (!pred_is_in_diamond) {
+      this->InvertDiamond(&orig[0], &orig[1]);
+    }
+    orig = orig + t;
+    return orig;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_DECODING_TRANSFORM_H_
+#endif

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_encoding_transform.h

@@ -0,0 +1,105 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_ENCODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_ENCODING_TRANSFORM_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_transform_base.h"
+#include "draco/core/encoder_buffer.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+
+namespace draco {
+
+// The transform works on octahedral coordinates for normals. The square is
+// subdivided into four inner triangles (diamond) and four outer triangles. The
+// inner triangles are associated with the upper part of the octahedron and the
+// outer triangles are associated with the lower part.
+// Given a prediction value P and the actual value Q that should be encoded,
+// this transform first checks if P is outside the diamond. If so, the outer
+// triangles are flipped towards the inside and vice versa. The actual
+// correction value is then based on the mapped P and Q values. This tends to
+// result in shorter correction vectors.
+// This is possible since the P value is also known by the decoder, see also
+// ComputeCorrection and ComputeOriginalValue functions.
+// Note that the tile is not periodic, which implies that the outer edges can
+// not be identified, which requires us to use an odd number of values on each
+// axis.
+// DataTypeT is expected to be some integral type.
+//
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronEncodingTransform
+    : public PredictionSchemeNormalOctahedronTransformBase<DataTypeT> {
+ public:
+  typedef PredictionSchemeNormalOctahedronTransformBase<DataTypeT> Base;
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT CorrType;
+  typedef DataTypeT DataType;
+
+  // We expect the mod value to be of the form 2^b-1.
+  explicit PredictionSchemeNormalOctahedronEncodingTransform(
+      DataType max_quantized_value)
+      : Base(max_quantized_value) {}
+
+  void Init(const DataTypeT *orig_data, int size, int num_components) {}
+
+  bool EncodeTransformData(EncoderBuffer *buffer) {
+    buffer->Encode(this->max_quantized_value());
+    return true;
+  }
+
+  inline void ComputeCorrection(const DataType *orig_vals,
+                                const DataType *pred_vals,
+                                CorrType *out_corr_vals) const {
+    DRACO_DCHECK_LE(pred_vals[0], this->center_value() * 2);
+    DRACO_DCHECK_LE(pred_vals[1], this->center_value() * 2);
+    DRACO_DCHECK_LE(orig_vals[0], this->center_value() * 2);
+    DRACO_DCHECK_LE(orig_vals[1], this->center_value() * 2);
+    DRACO_DCHECK_LE(0, pred_vals[0]);
+    DRACO_DCHECK_LE(0, pred_vals[1]);
+    DRACO_DCHECK_LE(0, orig_vals[0]);
+    DRACO_DCHECK_LE(0, orig_vals[1]);
+
+    const Point2 orig = Point2(orig_vals[0], orig_vals[1]);
+    const Point2 pred = Point2(pred_vals[0], pred_vals[1]);
+    const Point2 corr = ComputeCorrection(orig, pred);
+
+    out_corr_vals[0] = corr[0];
+    out_corr_vals[1] = corr[1];
+  }
+
+ private:
+  Point2 ComputeCorrection(Point2 orig, Point2 pred) const {
+    const Point2 t(this->center_value(), this->center_value());
+    orig = orig - t;
+    pred = pred - t;
+
+    if (!this->IsInDiamond(pred[0], pred[1])) {
+      this->InvertDiamond(&orig[0], &orig[1]);
+      this->InvertDiamond(&pred[0], &pred[1]);
+    }
+
+    Point2 corr = orig - pred;
+    corr[0] = this->MakePositive(corr[0]);
+    corr[1] = this->MakePositive(corr[1]);
+    return corr;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_ENCODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_transform_base.h

@@ -0,0 +1,90 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_TRANSFORM_BASE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_TRANSFORM_BASE_H_
+
+#include <cmath>
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/bit_utils.h"
+#include "draco/core/macros.h"
+#include "draco/core/vector_d.h"
+
+namespace draco {
+
+// Base class containing shared functionality used by both encoding and decoding
+// octahedral normal prediction scheme transforms. See the encoding transform
+// for more details about the method.
+template <typename DataTypeT>
+class PredictionSchemeNormalOctahedronTransformBase {
+ public:
+  typedef VectorD<DataTypeT, 2> Point2;
+  typedef DataTypeT DataType;
+
+  PredictionSchemeNormalOctahedronTransformBase() {}
+  // We expect the mod value to be of the form 2^b-1.
+  explicit PredictionSchemeNormalOctahedronTransformBase(
+      DataType max_quantized_value) {
+    this->set_max_quantized_value(max_quantized_value);
+  }
+
+  static constexpr PredictionSchemeTransformType GetType() {
+    return PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON;
+  }
+
+  // We can return true as we keep correction values positive.
+  bool AreCorrectionsPositive() const { return true; }
+
+  inline DataTypeT max_quantized_value() const {
+    return octahedron_tool_box_.max_quantized_value();
+  }
+  inline DataTypeT center_value() const {
+    return octahedron_tool_box_.center_value();
+  }
+  inline int32_t quantization_bits() const {
+    return octahedron_tool_box_.quantization_bits();
+  }
+
+ protected:
+  inline bool set_max_quantized_value(DataTypeT max_quantized_value) {
+    if (max_quantized_value % 2 == 0) {
+      return false;
+    }
+    int q = MostSignificantBit(max_quantized_value) + 1;
+    return octahedron_tool_box_.SetQuantizationBits(q);
+  }
+
+  bool IsInDiamond(DataTypeT s, DataTypeT t) const {
+    return octahedron_tool_box_.IsInDiamond(s, t);
+  }
+  void InvertDiamond(DataTypeT *s, DataTypeT *t) const {
+    return octahedron_tool_box_.InvertDiamond(s, t);
+  }
+
+  int32_t ModMax(int32_t x) const { return octahedron_tool_box_.ModMax(x); }
+
+  // For correction values.
+  int32_t MakePositive(int32_t x) const {
+    return octahedron_tool_box_.MakePositive(x);
+  }
+
+ private:
+  OctahedronToolBox octahedron_tool_box_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_NORMAL_OCTAHEDRON_TRANSFORM_BASE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_transform_test.cc

@@ -0,0 +1,71 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_encoding_transform.h"
+#include "draco/core/draco_test_base.h"
+
+namespace {
+
+class PredictionSchemeNormalOctahedronTransformTest : public ::testing::Test {
+ protected:
+  typedef draco::PredictionSchemeNormalOctahedronEncodingTransform<int32_t>
+      Transform;
+  typedef Transform::Point2 Point2;
+
+  void TestComputeCorrection(const Transform &transform, const int32_t &ox,
+                             const int32_t &oy, const int32_t &px,
+                             const int32_t &py, const int32_t &cx,
+                             const int32_t &cy) {
+    const int32_t o[2] = {ox + 7, oy + 7};
+    const int32_t p[2] = {px + 7, py + 7};
+    int32_t corr[2] = {500, 500};
+    transform.ComputeCorrection(o, p, corr);
+    ASSERT_EQ(corr[0], (cx + 15) % 15);
+    ASSERT_EQ(corr[1], (cy + 15) % 15);
+  }
+};
+
+TEST_F(PredictionSchemeNormalOctahedronTransformTest, Init) {
+  const Transform transform(15);
+  ASSERT_TRUE(transform.AreCorrectionsPositive());
+}
+
+TEST_F(PredictionSchemeNormalOctahedronTransformTest, ComputeCorrections) {
+  const Transform transform(15);
+  // checks inside diamond
+  TestComputeCorrection(transform, 0, 0, 0, 0, 0, 0);
+  TestComputeCorrection(transform, 1, 1, 1, 1, 0, 0);
+  TestComputeCorrection(transform, 3, 4, 1, 1, 2, 3);
+  TestComputeCorrection(transform, -1, -1, -1, -1, 0, 0);
+  TestComputeCorrection(transform, -3, -4, -1, -1, -2, -3);
+  // checks outside diamond
+  TestComputeCorrection(transform, 4, 4, 4, 4, 0, 0);
+  TestComputeCorrection(transform, 5, 6, 4, 4, -2, -1);
+  TestComputeCorrection(transform, 3, 2, 4, 4, 2, 1);
+  // checks on outer edges
+  TestComputeCorrection(transform, 7, 7, 4, 4, -3, -3);
+  TestComputeCorrection(transform, 6, 7, 4, 4, -3, -2);
+  TestComputeCorrection(transform, -6, 7, 4, 4, -3, -2);
+  TestComputeCorrection(transform, 7, 6, 4, 4, -2, -3);
+  TestComputeCorrection(transform, 7, -6, 4, 4, -2, -3);
+}
+
+TEST_F(PredictionSchemeNormalOctahedronTransformTest, Interface) {
+  const Transform transform(15);
+  ASSERT_EQ(transform.max_quantized_value(), 15);
+  ASSERT_EQ(transform.center_value(), 7);
+  ASSERT_EQ(transform.quantization_bits(), 4);
+}
+
+}  // namespace

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_decoding_transform.h

@@ -0,0 +1,88 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_DECODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_DECODING_TRANSFORM_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.h"
+#include "draco/core/decoder_buffer.h"
+
+namespace draco {
+
+// PredictionSchemeWrapDecodingTransform unwraps values encoded with the
+// PredictionSchemeWrapEncodingTransform.
+// See prediction_scheme_wrap_transform_base.h for more details about the
+// method.
+template <typename DataTypeT, typename CorrTypeT = DataTypeT>
+class PredictionSchemeWrapDecodingTransform
+    : public PredictionSchemeWrapTransformBase<DataTypeT> {
+ public:
+  typedef CorrTypeT CorrType;
+  PredictionSchemeWrapDecodingTransform() {}
+
+  // Computes the original value from the input predicted value and the decoded
+  // corrections. Values out of the bounds of the input values are unwrapped.
+  inline void ComputeOriginalValue(const DataTypeT *predicted_vals,
+                                   const CorrTypeT *corr_vals,
+                                   DataTypeT *out_original_vals) const {
+    // For now we assume both |DataTypeT| and |CorrTypeT| are equal.
+    static_assert(std::is_same<DataTypeT, CorrTypeT>::value,
+                  "Predictions and corrections must have the same type.");
+
+    // The only valid implementation right now is for int32_t.
+    static_assert(std::is_same<DataTypeT, int32_t>::value,
+                  "Only int32_t is supported for predicted values.");
+
+    predicted_vals = this->ClampPredictedValue(predicted_vals);
+
+    // Perform the wrapping using unsigned coordinates to avoid potential signed
+    // integer overflows caused by malformed input.
+    const uint32_t *const uint_predicted_vals =
+        reinterpret_cast<const uint32_t *>(predicted_vals);
+    const uint32_t *const uint_corr_vals =
+        reinterpret_cast<const uint32_t *>(corr_vals);
+    for (int i = 0; i < this->num_components(); ++i) {
+      out_original_vals[i] =
+          static_cast<DataTypeT>(uint_predicted_vals[i] + uint_corr_vals[i]);
+      if (out_original_vals[i] > this->max_value()) {
+        out_original_vals[i] -= this->max_dif();
+      } else if (out_original_vals[i] < this->min_value()) {
+        out_original_vals[i] += this->max_dif();
+      }
+    }
+  }
+
+  bool DecodeTransformData(DecoderBuffer *buffer) {
+    DataTypeT min_value, max_value;
+    if (!buffer->Decode(&min_value)) {
+      return false;
+    }
+    if (!buffer->Decode(&max_value)) {
+      return false;
+    }
+    if (min_value > max_value) {
+      return false;
+    }
+    this->set_min_value(min_value);
+    this->set_max_value(max_value);
+    if (!this->InitCorrectionBounds()) {
+      return false;
+    }
+    return true;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_DECODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_encoding_transform.h

@@ -0,0 +1,81 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_ENCODING_TRANSFORM_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_ENCODING_TRANSFORM_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.h"
+#include "draco/core/encoder_buffer.h"
+
+namespace draco {
+
+// PredictionSchemeWrapEncodingTransform wraps input values using the wrapping
+// scheme described in: prediction_scheme_wrap_transform_base.h .
+template <typename DataTypeT, typename CorrTypeT = DataTypeT>
+class PredictionSchemeWrapEncodingTransform
+    : public PredictionSchemeWrapTransformBase<DataTypeT> {
+ public:
+  typedef CorrTypeT CorrType;
+  PredictionSchemeWrapEncodingTransform() {}
+
+  void Init(const DataTypeT *orig_data, int size, int num_components) {
+    PredictionSchemeWrapTransformBase<DataTypeT>::Init(num_components);
+    // Go over the original values and compute the bounds.
+    if (size == 0) {
+      return;
+    }
+    DataTypeT min_value = orig_data[0];
+    DataTypeT max_value = min_value;
+    for (int i = 1; i < size; ++i) {
+      if (orig_data[i] < min_value) {
+        min_value = orig_data[i];
+      } else if (orig_data[i] > max_value) {
+        max_value = orig_data[i];
+      }
+    }
+    this->set_min_value(min_value);
+    this->set_max_value(max_value);
+    this->InitCorrectionBounds();
+  }
+
+  // Computes the corrections based on the input original value and the
+  // predicted value. Out of bound correction values are wrapped around the max
+  // range of input values.
+  inline void ComputeCorrection(const DataTypeT *original_vals,
+                                const DataTypeT *predicted_vals,
+                                CorrTypeT *out_corr_vals) const {
+    for (int i = 0; i < this->num_components(); ++i) {
+      predicted_vals = this->ClampPredictedValue(predicted_vals);
+      out_corr_vals[i] = original_vals[i] - predicted_vals[i];
+      // Wrap around if needed.
+      DataTypeT &corr_val = out_corr_vals[i];
+      if (corr_val < this->min_correction()) {
+        corr_val += this->max_dif();
+      } else if (corr_val > this->max_correction()) {
+        corr_val -= this->max_dif();
+      }
+    }
+  }
+
+  bool EncodeTransformData(EncoderBuffer *buffer) {
+    // Store the input value range as it is needed by the decoder.
+    buffer->Encode(this->min_value());
+    buffer->Encode(this->max_value());
+    return true;
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_ENCODING_TRANSFORM_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_transform_base.h

@@ -0,0 +1,120 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_
+
+#include <limits>
+#include <vector>
+
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/macros.h"
+
+namespace draco {
+
+// PredictionSchemeWrapTransform uses the min and max bounds of the original
+// data to wrap stored correction values around these bounds centered at 0,
+// i.e., when the range of the original values O is between <MIN, MAX> and
+// N = MAX-MIN, we can then store any correction X = O - P, as:
+//        X + N,   if X < -N / 2
+//        X - N,   if X > N / 2
+//        X        otherwise
+// To unwrap this value, the decoder then simply checks whether the final
+// corrected value F = P + X is out of the bounds of the input values.
+// All out of bounds values are unwrapped using
+//        F + N,   if F < MIN
+//        F - N,   if F > MAX
+// This wrapping can reduce the number of unique values, which translates to a
+// better entropy of the stored values and better compression rates.
+template <typename DataTypeT>
+class PredictionSchemeWrapTransformBase {
+ public:
+  PredictionSchemeWrapTransformBase()
+      : num_components_(0),
+        min_value_(0),
+        max_value_(0),
+        max_dif_(0),
+        max_correction_(0),
+        min_correction_(0) {}
+
+  static constexpr PredictionSchemeTransformType GetType() {
+    return PREDICTION_TRANSFORM_WRAP;
+  }
+
+  void Init(int num_components) {
+    num_components_ = num_components;
+    clamped_value_.resize(num_components);
+  }
+
+  bool AreCorrectionsPositive() const { return false; }
+
+  inline const DataTypeT *ClampPredictedValue(
+      const DataTypeT *predicted_val) const {
+    for (int i = 0; i < this->num_components(); ++i) {
+      if (predicted_val[i] > max_value_) {
+        clamped_value_[i] = max_value_;
+      } else if (predicted_val[i] < min_value_) {
+        clamped_value_[i] = min_value_;
+      } else {
+        clamped_value_[i] = predicted_val[i];
+      }
+    }
+    return &clamped_value_[0];
+  }
+
+  // TODO(hemmer): Consider refactoring to avoid this dummy.
+  int quantization_bits() const {
+    DRACO_DCHECK(false);
+    return -1;
+  }
+
+ protected:
+  bool InitCorrectionBounds() {
+    const int64_t dif =
+        static_cast<int64_t>(max_value_) - static_cast<int64_t>(min_value_);
+    if (dif < 0 || dif >= std::numeric_limits<DataTypeT>::max()) {
+      return false;
+    }
+    max_dif_ = 1 + static_cast<DataTypeT>(dif);
+    max_correction_ = max_dif_ / 2;
+    min_correction_ = -max_correction_;
+    if ((max_dif_ & 1) == 0) {
+      max_correction_ -= 1;
+    }
+    return true;
+  }
+
+  inline int num_components() const { return num_components_; }
+  inline DataTypeT min_value() const { return min_value_; }
+  inline void set_min_value(const DataTypeT &v) { min_value_ = v; }
+  inline DataTypeT max_value() const { return max_value_; }
+  inline void set_max_value(const DataTypeT &v) { max_value_ = v; }
+  inline DataTypeT max_dif() const { return max_dif_; }
+  inline DataTypeT min_correction() const { return min_correction_; }
+  inline DataTypeT max_correction() const { return max_correction_; }
+
+ private:
+  int num_components_;
+  DataTypeT min_value_;
+  DataTypeT max_value_;
+  DataTypeT max_dif_;
+  DataTypeT max_correction_;
+  DataTypeT min_correction_;
+  // This is in fact just a tmp variable to avoid reallocation.
+  mutable std::vector<DataTypeT> clamped_value_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_PREDICTION_SCHEMES_PREDICTION_SCHEME_WRAP_TRANSFORM_BASE_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_decoder.cc

@@ -0,0 +1,118 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_attribute_decoder.h"
+
+namespace draco {
+
+SequentialAttributeDecoder::SequentialAttributeDecoder()
+    : decoder_(nullptr), attribute_(nullptr), attribute_id_(-1) {}
+
+bool SequentialAttributeDecoder::Init(PointCloudDecoder *decoder,
+                                      int attribute_id) {
+  decoder_ = decoder;
+  attribute_ = decoder->point_cloud()->attribute(attribute_id);
+  attribute_id_ = attribute_id;
+  return true;
+}
+
+bool SequentialAttributeDecoder::InitializeStandalone(
+    PointAttribute *attribute) {
+  attribute_ = attribute;
+  attribute_id_ = -1;
+  return true;
+}
+
+bool SequentialAttributeDecoder::DecodePortableAttribute(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  if (attribute_->num_components() <= 0 ||
+      !attribute_->Reset(point_ids.size())) {
+    return false;
+  }
+  if (!DecodeValues(point_ids, in_buffer)) {
+    return false;
+  }
+  return true;
+}
+
+bool SequentialAttributeDecoder::DecodeDataNeededByPortableTransform(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  // Default implementation does not apply any transform.
+  return true;
+}
+
+bool SequentialAttributeDecoder::TransformAttributeToOriginalFormat(
+    const std::vector<PointIndex> &point_ids) {
+  // Default implementation does not apply any transform.
+  return true;
+}
+
+const PointAttribute *SequentialAttributeDecoder::GetPortableAttribute() {
+  // If needed, copy point to attribute value index mapping from the final
+  // attribute to the portable attribute.
+  if (!attribute_->is_mapping_identity() && portable_attribute_ &&
+      portable_attribute_->is_mapping_identity()) {
+    portable_attribute_->SetExplicitMapping(attribute_->indices_map_size());
+    for (PointIndex i(0);
+         i < static_cast<uint32_t>(attribute_->indices_map_size()); ++i) {
+      portable_attribute_->SetPointMapEntry(i, attribute_->mapped_index(i));
+    }
+  }
+  return portable_attribute_.get();
+}
+
+bool SequentialAttributeDecoder::InitPredictionScheme(
+    PredictionSchemeInterface *ps) {
+  for (int i = 0; i < ps->GetNumParentAttributes(); ++i) {
+    const int att_id = decoder_->point_cloud()->GetNamedAttributeId(
+        ps->GetParentAttributeType(i));
+    if (att_id == -1) {
+      return false;  // Requested attribute does not exist.
+    }
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+    if (decoder_->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 0)) {
+      if (!ps->SetParentAttribute(decoder_->point_cloud()->attribute(att_id))) {
+        return false;
+      }
+    } else
+#endif
+    {
+      const PointAttribute *const pa = decoder_->GetPortableAttribute(att_id);
+      if (pa == nullptr || !ps->SetParentAttribute(pa)) {
+        return false;
+      }
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeDecoder::DecodeValues(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  const int32_t num_values = static_cast<uint32_t>(point_ids.size());
+  const int entry_size = static_cast<int>(attribute_->byte_stride());
+  std::unique_ptr<uint8_t[]> value_data_ptr(new uint8_t[entry_size]);
+  uint8_t *const value_data = value_data_ptr.get();
+  int out_byte_pos = 0;
+  // Decode raw attribute values in their original format.
+  for (int i = 0; i < num_values; ++i) {
+    if (!in_buffer->Decode(value_data, entry_size)) {
+      return false;
+    }
+    attribute_->buffer()->Write(out_byte_pos, value_data, entry_size);
+    out_byte_pos += entry_size;
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_decoder.h

@@ -0,0 +1,86 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_interface.h"
+#include "draco/compression/point_cloud/point_cloud_decoder.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// A base class for decoding attribute values encoded by the
+// SequentialAttributeEncoder.
+class SequentialAttributeDecoder {
+ public:
+  SequentialAttributeDecoder();
+  virtual ~SequentialAttributeDecoder() = default;
+
+  virtual bool Init(PointCloudDecoder *decoder, int attribute_id);
+
+  // Initialization for a specific attribute. This can be used mostly for
+  // standalone decoding of an attribute without an PointCloudDecoder.
+  virtual bool InitializeStandalone(PointAttribute *attribute);
+
+  // Performs lossless decoding of the portable attribute data.
+  virtual bool DecodePortableAttribute(const std::vector<PointIndex> &point_ids,
+                                       DecoderBuffer *in_buffer);
+
+  // Decodes any data needed to revert portable transform of the decoded
+  // attribute.
+  virtual bool DecodeDataNeededByPortableTransform(
+      const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer);
+
+  // Reverts transformation performed by encoder in
+  // SequentialAttributeEncoder::TransformAttributeToPortableFormat() method.
+  virtual bool TransformAttributeToOriginalFormat(
+      const std::vector<PointIndex> &point_ids);
+
+  const PointAttribute *GetPortableAttribute();
+
+  const PointAttribute *attribute() const { return attribute_; }
+  PointAttribute *attribute() { return attribute_; }
+  int attribute_id() const { return attribute_id_; }
+  PointCloudDecoder *decoder() const { return decoder_; }
+
+ protected:
+  // Should be used to initialize newly created prediction scheme.
+  // Returns false when the initialization failed (in which case the scheme
+  // cannot be used).
+  virtual bool InitPredictionScheme(PredictionSchemeInterface *ps);
+
+  // The actual implementation of the attribute decoding. Should be overridden
+  // for specialized decoders.
+  virtual bool DecodeValues(const std::vector<PointIndex> &point_ids,
+                            DecoderBuffer *in_buffer);
+
+  void SetPortableAttribute(std::unique_ptr<PointAttribute> att) {
+    portable_attribute_ = std::move(att);
+  }
+
+  PointAttribute *portable_attribute() { return portable_attribute_.get(); }
+
+ private:
+  PointCloudDecoder *decoder_;
+  PointAttribute *attribute_;
+  int attribute_id_;
+
+  // Storage for decoded portable attribute (after lossless decoding).
+  std::unique_ptr<PointAttribute> portable_attribute_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_decoders_controller.cc

@@ -0,0 +1,149 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_attribute_decoders_controller.h"
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+#include "draco/compression/attributes/sequential_normal_attribute_decoder.h"
+#endif
+#include "draco/compression/attributes/sequential_quantization_attribute_decoder.h"
+#include "draco/compression/config/compression_shared.h"
+
+namespace draco {
+
+SequentialAttributeDecodersController::SequentialAttributeDecodersController(
+    std::unique_ptr<PointsSequencer> sequencer)
+    : sequencer_(std::move(sequencer)) {}
+
+bool SequentialAttributeDecodersController::DecodeAttributesDecoderData(
+    DecoderBuffer *buffer) {
+  if (!AttributesDecoder::DecodeAttributesDecoderData(buffer)) {
+    return false;
+  }
+  // Decode unique ids of all sequential encoders and create them.
+  const int32_t num_attributes = GetNumAttributes();
+  sequential_decoders_.resize(num_attributes);
+  for (int i = 0; i < num_attributes; ++i) {
+    uint8_t decoder_type;
+    if (!buffer->Decode(&decoder_type)) {
+      return false;
+    }
+    // Create the decoder from the id.
+    sequential_decoders_[i] = CreateSequentialDecoder(decoder_type);
+    if (!sequential_decoders_[i]) {
+      return false;
+    }
+    if (!sequential_decoders_[i]->Init(GetDecoder(), GetAttributeId(i))) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeDecodersController::DecodeAttributes(
+    DecoderBuffer *buffer) {
+  if (!sequencer_ || !sequencer_->GenerateSequence(&point_ids_)) {
+    return false;
+  }
+  // Initialize point to attribute value mapping for all decoded attributes.
+  const int32_t num_attributes = GetNumAttributes();
+  for (int i = 0; i < num_attributes; ++i) {
+    PointAttribute *const pa =
+        GetDecoder()->point_cloud()->attribute(GetAttributeId(i));
+    if (!sequencer_->UpdatePointToAttributeIndexMapping(pa)) {
+      return false;
+    }
+  }
+  return AttributesDecoder::DecodeAttributes(buffer);
+}
+
+bool SequentialAttributeDecodersController::DecodePortableAttributes(
+    DecoderBuffer *in_buffer) {
+  const int32_t num_attributes = GetNumAttributes();
+  for (int i = 0; i < num_attributes; ++i) {
+    if (!sequential_decoders_[i]->DecodePortableAttribute(point_ids_,
+                                                          in_buffer)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeDecodersController::
+    DecodeDataNeededByPortableTransforms(DecoderBuffer *in_buffer) {
+  const int32_t num_attributes = GetNumAttributes();
+  for (int i = 0; i < num_attributes; ++i) {
+    if (!sequential_decoders_[i]->DecodeDataNeededByPortableTransform(
+            point_ids_, in_buffer)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeDecodersController::
+    TransformAttributesToOriginalFormat() {
+  const int32_t num_attributes = GetNumAttributes();
+  for (int i = 0; i < num_attributes; ++i) {
+    // Check whether the attribute transform should be skipped.
+    if (GetDecoder()->options()) {
+      const PointAttribute *const attribute =
+          sequential_decoders_[i]->attribute();
+      const PointAttribute *const portable_attribute =
+          sequential_decoders_[i]->GetPortableAttribute();
+      if (portable_attribute &&
+          GetDecoder()->options()->GetAttributeBool(
+              attribute->attribute_type(), "skip_attribute_transform", false)) {
+        // Attribute transform should not be performed. In this case, we replace
+        // the output geometry attribute with the portable attribute.
+        // TODO(ostava): We can potentially avoid this copy by introducing a new
+        // mechanism that would allow to use the final attributes as portable
+        // attributes for predictors that may need them.
+        sequential_decoders_[i]->attribute()->CopyFrom(*portable_attribute);
+        continue;
+      }
+    }
+    if (!sequential_decoders_[i]->TransformAttributeToOriginalFormat(
+            point_ids_)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+std::unique_ptr<SequentialAttributeDecoder>
+SequentialAttributeDecodersController::CreateSequentialDecoder(
+    uint8_t decoder_type) {
+  switch (decoder_type) {
+    case SEQUENTIAL_ATTRIBUTE_ENCODER_GENERIC:
+      return std::unique_ptr<SequentialAttributeDecoder>(
+          new SequentialAttributeDecoder());
+    case SEQUENTIAL_ATTRIBUTE_ENCODER_INTEGER:
+      return std::unique_ptr<SequentialAttributeDecoder>(
+          new SequentialIntegerAttributeDecoder());
+    case SEQUENTIAL_ATTRIBUTE_ENCODER_QUANTIZATION:
+      return std::unique_ptr<SequentialAttributeDecoder>(
+          new SequentialQuantizationAttributeDecoder());
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+    case SEQUENTIAL_ATTRIBUTE_ENCODER_NORMALS:
+      return std::unique_ptr<SequentialNormalAttributeDecoder>(
+          new SequentialNormalAttributeDecoder());
+#endif
+    default:
+      break;
+  }
+  // Unknown or unsupported decoder type.
+  return nullptr;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_decoders_controller.h

@@ -0,0 +1,61 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODERS_CONTROLLER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODERS_CONTROLLER_H_
+
+#include "draco/compression/attributes/attributes_decoder.h"
+#include "draco/compression/attributes/points_sequencer.h"
+#include "draco/compression/attributes/sequential_attribute_decoder.h"
+
+namespace draco {
+
+// A basic implementation of an attribute decoder that decodes data encoded by
+// the SequentialAttributeEncodersController class. The
+// SequentialAttributeDecodersController creates a single
+// AttributeIndexedValuesDecoder for each of the decoded attribute, where the
+// type of the values decoder is determined by the unique identifier that was
+// encoded by the encoder.
+class SequentialAttributeDecodersController : public AttributesDecoder {
+ public:
+  explicit SequentialAttributeDecodersController(
+      std::unique_ptr<PointsSequencer> sequencer);
+
+  bool DecodeAttributesDecoderData(DecoderBuffer *buffer) override;
+  bool DecodeAttributes(DecoderBuffer *buffer) override;
+  const PointAttribute *GetPortableAttribute(
+      int32_t point_attribute_id) override {
+    const int32_t loc_id = GetLocalIdForPointAttribute(point_attribute_id);
+    if (loc_id < 0) {
+      return nullptr;
+    }
+    return sequential_decoders_[loc_id]->GetPortableAttribute();
+  }
+
+ protected:
+  bool DecodePortableAttributes(DecoderBuffer *in_buffer) override;
+  bool DecodeDataNeededByPortableTransforms(DecoderBuffer *in_buffer) override;
+  bool TransformAttributesToOriginalFormat() override;
+  virtual std::unique_ptr<SequentialAttributeDecoder> CreateSequentialDecoder(
+      uint8_t decoder_type);
+
+ private:
+  std::vector<std::unique_ptr<SequentialAttributeDecoder>> sequential_decoders_;
+  std::vector<PointIndex> point_ids_;
+  std::unique_ptr<PointsSequencer> sequencer_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_DECODERS_CONTROLLER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_encoder.cc

@@ -0,0 +1,108 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_attribute_encoder.h"
+
+namespace draco {
+
+SequentialAttributeEncoder::SequentialAttributeEncoder()
+    : encoder_(nullptr),
+      attribute_(nullptr),
+      attribute_id_(-1),
+      is_parent_encoder_(false) {}
+
+bool SequentialAttributeEncoder::Init(PointCloudEncoder *encoder,
+                                      int attribute_id) {
+  encoder_ = encoder;
+  attribute_ = encoder_->point_cloud()->attribute(attribute_id);
+  attribute_id_ = attribute_id;
+  return true;
+}
+
+bool SequentialAttributeEncoder::InitializeStandalone(
+    PointAttribute *attribute) {
+  attribute_ = attribute;
+  attribute_id_ = -1;
+  return true;
+}
+
+bool SequentialAttributeEncoder::TransformAttributeToPortableFormat(
+    const std::vector<PointIndex> &point_ids) {
+  // Default implementation doesn't transform the input data.
+  return true;
+}
+
+bool SequentialAttributeEncoder::EncodePortableAttribute(
+    const std::vector<PointIndex> &point_ids, EncoderBuffer *out_buffer) {
+  // Lossless encoding of the input values.
+  if (!EncodeValues(point_ids, out_buffer)) {
+    return false;
+  }
+  return true;
+}
+
+bool SequentialAttributeEncoder::EncodeDataNeededByPortableTransform(
+    EncoderBuffer *out_buffer) {
+  // Default implementation doesn't transform the input data.
+  return true;
+}
+
+bool SequentialAttributeEncoder::EncodeValues(
+    const std::vector<PointIndex> &point_ids, EncoderBuffer *out_buffer) {
+  const int entry_size = static_cast<int>(attribute_->byte_stride());
+  const std::unique_ptr<uint8_t[]> value_data_ptr(new uint8_t[entry_size]);
+  uint8_t *const value_data = value_data_ptr.get();
+  // Encode all attribute values in their native raw format.
+  for (uint32_t i = 0; i < point_ids.size(); ++i) {
+    const AttributeValueIndex entry_id = attribute_->mapped_index(point_ids[i]);
+    attribute_->GetValue(entry_id, value_data);
+    out_buffer->Encode(value_data, entry_size);
+  }
+  return true;
+}
+
+void SequentialAttributeEncoder::MarkParentAttribute() {
+  is_parent_encoder_ = true;
+}
+
+bool SequentialAttributeEncoder::InitPredictionScheme(
+    PredictionSchemeInterface *ps) {
+  for (int i = 0; i < ps->GetNumParentAttributes(); ++i) {
+    const int att_id = encoder_->point_cloud()->GetNamedAttributeId(
+        ps->GetParentAttributeType(i));
+    if (att_id == -1) {
+      return false;  // Requested attribute does not exist.
+    }
+    parent_attributes_.push_back(att_id);
+    encoder_->MarkParentAttribute(att_id);
+  }
+  return true;
+}
+
+bool SequentialAttributeEncoder::SetPredictionSchemeParentAttributes(
+    PredictionSchemeInterface *ps) {
+  for (int i = 0; i < ps->GetNumParentAttributes(); ++i) {
+    const int att_id = encoder_->point_cloud()->GetNamedAttributeId(
+        ps->GetParentAttributeType(i));
+    if (att_id == -1) {
+      return false;  // Requested attribute does not exist.
+    }
+    if (!ps->SetParentAttribute(encoder_->GetPortableAttribute(att_id))) {
+      return false;
+    }
+  }
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_encoder.h

@@ -0,0 +1,134 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_interface.h"
+#include "draco/compression/point_cloud/point_cloud_encoder.h"
+
+namespace draco {
+
+// A base class for encoding attribute values of a single attribute using a
+// given sequence of point ids. The default implementation encodes all attribute
+// values directly to the buffer but derived classes can perform any custom
+// encoding (such as quantization) by overriding the EncodeValues() method.
+class SequentialAttributeEncoder {
+ public:
+  SequentialAttributeEncoder();
+  virtual ~SequentialAttributeEncoder() = default;
+
+  // Method that can be used for custom initialization of an attribute encoder,
+  // such as creation of prediction schemes and initialization of attribute
+  // encoder dependencies.
+  // |encoder| is the parent PointCloudEncoder,
+  // |attribute_id| is the id of the attribute that is being encoded by this
+  // encoder.
+  // This method is automatically called by the PointCloudEncoder after all
+  // attribute encoders are created and it should not be called explicitly from
+  // other places.
+  virtual bool Init(PointCloudEncoder *encoder, int attribute_id);
+
+  // Initialization for a specific attribute. This can be used mostly for
+  // standalone encoding of an attribute without an PointCloudEncoder.
+  virtual bool InitializeStandalone(PointAttribute *attribute);
+
+  // Transforms attribute data into format that is going to be encoded
+  // losslessly. The transform itself can be lossy.
+  virtual bool TransformAttributeToPortableFormat(
+      const std::vector<PointIndex> &point_ids);
+
+  // Performs lossless encoding of the transformed attribute data.
+  virtual bool EncodePortableAttribute(const std::vector<PointIndex> &point_ids,
+                                       EncoderBuffer *out_buffer);
+
+  // Encodes any data related to the portable attribute transform.
+  virtual bool EncodeDataNeededByPortableTransform(EncoderBuffer *out_buffer);
+
+  virtual bool IsLossyEncoder() const { return false; }
+
+  int NumParentAttributes() const {
+    return static_cast<int>(parent_attributes_.size());
+  }
+  int GetParentAttributeId(int i) const { return parent_attributes_[i]; }
+
+  const PointAttribute *GetPortableAttribute() const {
+    if (portable_attribute_ != nullptr) {
+      return portable_attribute_.get();
+    }
+    return attribute();
+  }
+
+  // Called when this attribute encoder becomes a parent encoder of another
+  // encoder.
+  void MarkParentAttribute();
+
+  virtual uint8_t GetUniqueId() const {
+    return SEQUENTIAL_ATTRIBUTE_ENCODER_GENERIC;
+  }
+
+  const PointAttribute *attribute() const { return attribute_; }
+  int attribute_id() const { return attribute_id_; }
+  PointCloudEncoder *encoder() const { return encoder_; }
+
+ protected:
+  // Should be used to initialize newly created prediction scheme.
+  // Returns false when the initialization failed (in which case the scheme
+  // cannot be used).
+  virtual bool InitPredictionScheme(PredictionSchemeInterface *ps);
+
+  // Sets parent attributes for a given prediction scheme. Must be called
+  // after all prediction schemes are initialized, but before the prediction
+  // scheme is used.
+  virtual bool SetPredictionSchemeParentAttributes(
+      PredictionSchemeInterface *ps);
+
+  // Encodes all attribute values in the specified order. Should be overridden
+  // for specialized  encoders.
+  virtual bool EncodeValues(const std::vector<PointIndex> &point_ids,
+                            EncoderBuffer *out_buffer);
+
+  bool is_parent_encoder() const { return is_parent_encoder_; }
+
+  void SetPortableAttribute(std::unique_ptr<PointAttribute> att) {
+    portable_attribute_ = std::move(att);
+  }
+
+  // Returns a mutable attribute that should be filled by derived encoders with
+  // the transformed version of the attribute data. To get a public const
+  // version, use the GetPortableAttribute() method.
+  PointAttribute *portable_attribute() { return portable_attribute_.get(); }
+
+ private:
+  PointCloudEncoder *encoder_;
+  const PointAttribute *attribute_;
+  int attribute_id_;
+
+  // List of attribute encoders that need to be encoded before this attribute.
+  // E.g. The parent attributes may be used to predict values used by this
+  // attribute encoder.
+  std::vector<int32_t> parent_attributes_;
+
+  bool is_parent_encoder_;
+
+  // Attribute that stores transformed data from the source attribute after it
+  // is processed through the ApplyTransform() method. Attribute data stored
+  // within this attribute is guaranteed to be encoded losslessly and it can be
+  // safely used for prediction of other attributes.
+  std::unique_ptr<PointAttribute> portable_attribute_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_encoders_controller.cc

@@ -0,0 +1,159 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_attribute_encoders_controller.h"
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+#include "draco/compression/attributes/sequential_normal_attribute_encoder.h"
+#endif
+#include "draco/compression/attributes/sequential_quantization_attribute_encoder.h"
+#include "draco/compression/point_cloud/point_cloud_encoder.h"
+
+namespace draco {
+
+SequentialAttributeEncodersController::SequentialAttributeEncodersController(
+    std::unique_ptr<PointsSequencer> sequencer)
+    : sequencer_(std::move(sequencer)) {}
+
+SequentialAttributeEncodersController::SequentialAttributeEncodersController(
+    std::unique_ptr<PointsSequencer> sequencer, int point_attrib_id)
+    : AttributesEncoder(point_attrib_id), sequencer_(std::move(sequencer)) {}
+
+bool SequentialAttributeEncodersController::Init(PointCloudEncoder *encoder,
+                                                 const PointCloud *pc) {
+  if (!AttributesEncoder::Init(encoder, pc)) {
+    return false;
+  }
+  if (!CreateSequentialEncoders()) {
+    return false;
+  }
+  // Initialize all value encoders.
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    const int32_t att_id = GetAttributeId(i);
+    if (!sequential_encoders_[i]->Init(encoder, att_id)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeEncodersController::EncodeAttributesEncoderData(
+    EncoderBuffer *out_buffer) {
+  if (!AttributesEncoder::EncodeAttributesEncoderData(out_buffer)) {
+    return false;
+  }
+  // Encode a unique id of every sequential encoder.
+  for (uint32_t i = 0; i < sequential_encoders_.size(); ++i) {
+    out_buffer->Encode(sequential_encoders_[i]->GetUniqueId());
+  }
+  return true;
+}
+
+bool SequentialAttributeEncodersController::EncodeAttributes(
+    EncoderBuffer *buffer) {
+  if (!sequencer_ || !sequencer_->GenerateSequence(&point_ids_)) {
+    return false;
+  }
+  return AttributesEncoder::EncodeAttributes(buffer);
+}
+
+bool SequentialAttributeEncodersController::
+    TransformAttributesToPortableFormat() {
+  for (uint32_t i = 0; i < sequential_encoders_.size(); ++i) {
+    if (!sequential_encoders_[i]->TransformAttributeToPortableFormat(
+            point_ids_)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeEncodersController::EncodePortableAttributes(
+    EncoderBuffer *out_buffer) {
+  for (uint32_t i = 0; i < sequential_encoders_.size(); ++i) {
+    if (!sequential_encoders_[i]->EncodePortableAttribute(point_ids_,
+                                                          out_buffer)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeEncodersController::
+    EncodeDataNeededByPortableTransforms(EncoderBuffer *out_buffer) {
+  for (uint32_t i = 0; i < sequential_encoders_.size(); ++i) {
+    if (!sequential_encoders_[i]->EncodeDataNeededByPortableTransform(
+            out_buffer)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SequentialAttributeEncodersController::CreateSequentialEncoders() {
+  sequential_encoders_.resize(num_attributes());
+  for (uint32_t i = 0; i < num_attributes(); ++i) {
+    sequential_encoders_[i] = CreateSequentialEncoder(i);
+    if (sequential_encoders_[i] == nullptr) {
+      return false;
+    }
+    if (i < sequential_encoder_marked_as_parent_.size()) {
+      if (sequential_encoder_marked_as_parent_[i]) {
+        sequential_encoders_[i]->MarkParentAttribute();
+      }
+    }
+  }
+  return true;
+}
+
+std::unique_ptr<SequentialAttributeEncoder>
+SequentialAttributeEncodersController::CreateSequentialEncoder(int i) {
+  const int32_t att_id = GetAttributeId(i);
+  const PointAttribute *const att = encoder()->point_cloud()->attribute(att_id);
+
+  switch (att->data_type()) {
+    case DT_UINT8:
+    case DT_INT8:
+    case DT_UINT16:
+    case DT_INT16:
+    case DT_UINT32:
+    case DT_INT32:
+      return std::unique_ptr<SequentialAttributeEncoder>(
+          new SequentialIntegerAttributeEncoder());
+    case DT_FLOAT32:
+      if (encoder()->options()->GetAttributeInt(att_id, "quantization_bits",
+                                                -1) > 0) {
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+        if (att->attribute_type() == GeometryAttribute::NORMAL) {
+          // We currently only support normals with float coordinates
+          // and must be quantized.
+          return std::unique_ptr<SequentialAttributeEncoder>(
+              new SequentialNormalAttributeEncoder());
+        } else {
+#endif
+          return std::unique_ptr<SequentialAttributeEncoder>(
+              new SequentialQuantizationAttributeEncoder());
+#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
+        }
+#endif
+      }
+      break;
+    default:
+      break;
+  }
+  // Return the default attribute encoder.
+  return std::unique_ptr<SequentialAttributeEncoder>(
+      new SequentialAttributeEncoder());
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_attribute_encoders_controller.h

@@ -0,0 +1,115 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODERS_CONTROLLER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODERS_CONTROLLER_H_
+
+#include "draco/compression/attributes/attributes_encoder.h"
+#include "draco/compression/attributes/points_sequencer.h"
+#include "draco/compression/attributes/sequential_attribute_encoder.h"
+
+namespace draco {
+
+// A basic implementation of an attribute encoder that can be used to encode
+// an arbitrary set of attributes. The encoder creates a sequential attribute
+// encoder for each encoded attribute (see sequential_attribute_encoder.h) and
+// then it encodes all attribute values in an order defined by a point sequence
+// generated in the GeneratePointSequence() method. The default implementation
+// generates a linear sequence of all points, but derived classes can generate
+// any custom sequence.
+class SequentialAttributeEncodersController : public AttributesEncoder {
+ public:
+  explicit SequentialAttributeEncodersController(
+      std::unique_ptr<PointsSequencer> sequencer);
+  SequentialAttributeEncodersController(
+      std::unique_ptr<PointsSequencer> sequencer, int point_attrib_id);
+
+  bool Init(PointCloudEncoder *encoder, const PointCloud *pc) override;
+  bool EncodeAttributesEncoderData(EncoderBuffer *out_buffer) override;
+  bool EncodeAttributes(EncoderBuffer *buffer) override;
+  uint8_t GetUniqueId() const override { return BASIC_ATTRIBUTE_ENCODER; }
+
+  int NumParentAttributes(int32_t point_attribute_id) const override {
+    const int32_t loc_id = GetLocalIdForPointAttribute(point_attribute_id);
+    if (loc_id < 0) {
+      return 0;
+    }
+    return sequential_encoders_[loc_id]->NumParentAttributes();
+  }
+
+  int GetParentAttributeId(int32_t point_attribute_id,
+                           int32_t parent_i) const override {
+    const int32_t loc_id = GetLocalIdForPointAttribute(point_attribute_id);
+    if (loc_id < 0) {
+      return -1;
+    }
+    return sequential_encoders_[loc_id]->GetParentAttributeId(parent_i);
+  }
+
+  bool MarkParentAttribute(int32_t point_attribute_id) override {
+    const int32_t loc_id = GetLocalIdForPointAttribute(point_attribute_id);
+    if (loc_id < 0) {
+      return false;
+    }
+    // Mark the attribute encoder as parent (even when if it is not created
+    // yet).
+    if (sequential_encoder_marked_as_parent_.size() <= loc_id) {
+      sequential_encoder_marked_as_parent_.resize(loc_id + 1, false);
+    }
+    sequential_encoder_marked_as_parent_[loc_id] = true;
+
+    if (sequential_encoders_.size() <= loc_id) {
+      return true;  // Sequential encoders not generated yet.
+    }
+    sequential_encoders_[loc_id]->MarkParentAttribute();
+    return true;
+  }
+
+  const PointAttribute *GetPortableAttribute(
+      int32_t point_attribute_id) override {
+    const int32_t loc_id = GetLocalIdForPointAttribute(point_attribute_id);
+    if (loc_id < 0) {
+      return nullptr;
+    }
+    return sequential_encoders_[loc_id]->GetPortableAttribute();
+  }
+
+ protected:
+  bool TransformAttributesToPortableFormat() override;
+  bool EncodePortableAttributes(EncoderBuffer *out_buffer) override;
+  bool EncodeDataNeededByPortableTransforms(EncoderBuffer *out_buffer) override;
+
+  // Creates all sequential encoders (one for each attribute associated with the
+  // encoder).
+  virtual bool CreateSequentialEncoders();
+
+  // Create a sequential encoder for a given attribute based on the attribute
+  // type
+  // and the provided encoder options.
+  virtual std::unique_ptr<SequentialAttributeEncoder> CreateSequentialEncoder(
+      int i);
+
+ private:
+  std::vector<std::unique_ptr<SequentialAttributeEncoder>> sequential_encoders_;
+
+  // Flag for each sequential attribute encoder indicating whether it was marked
+  // as parent attribute or not.
+  std::vector<bool> sequential_encoder_marked_as_parent_;
+  std::vector<PointIndex> point_ids_;
+  std::unique_ptr<PointsSequencer> sequencer_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_ATTRIBUTE_ENCODERS_CONTROLLER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_integer_attribute_decoder.cc

@@ -0,0 +1,240 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_integer_attribute_decoder.h"
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder_factory.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_decoding_transform.h"
+#include "draco/compression/entropy/symbol_decoding.h"
+
+namespace draco {
+
+SequentialIntegerAttributeDecoder::SequentialIntegerAttributeDecoder() {}
+
+bool SequentialIntegerAttributeDecoder::Init(PointCloudDecoder *decoder,
+                                             int attribute_id) {
+  if (!SequentialAttributeDecoder::Init(decoder, attribute_id)) {
+    return false;
+  }
+  return true;
+}
+
+bool SequentialIntegerAttributeDecoder::TransformAttributeToOriginalFormat(
+    const std::vector<PointIndex> &point_ids) {
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (decoder() &&
+      decoder()->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 0)) {
+    return true;  // Don't revert the transform here for older files.
+  }
+#endif
+  return StoreValues(static_cast<uint32_t>(point_ids.size()));
+}
+
+bool SequentialIntegerAttributeDecoder::DecodeValues(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  // Decode prediction scheme.
+  int8_t prediction_scheme_method;
+  if (!in_buffer->Decode(&prediction_scheme_method)) {
+    return false;
+  }
+  if (prediction_scheme_method != PREDICTION_NONE) {
+    int8_t prediction_transform_type;
+    if (!in_buffer->Decode(&prediction_transform_type)) {
+      return false;
+    }
+    // Check that decoded prediction scheme transform type is valid.
+    if (prediction_transform_type < PREDICTION_TRANSFORM_NONE ||
+        prediction_transform_type >= NUM_PREDICTION_SCHEME_TRANSFORM_TYPES) {
+      return false;
+    }
+    prediction_scheme_ = CreateIntPredictionScheme(
+        static_cast<PredictionSchemeMethod>(prediction_scheme_method),
+        static_cast<PredictionSchemeTransformType>(prediction_transform_type));
+  }
+
+  if (prediction_scheme_) {
+    if (!InitPredictionScheme(prediction_scheme_.get())) {
+      return false;
+    }
+  }
+
+  if (!DecodeIntegerValues(point_ids, in_buffer)) {
+    return false;
+  }
+
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  const int32_t num_values = static_cast<uint32_t>(point_ids.size());
+  if (decoder() &&
+      decoder()->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 0)) {
+    // For older files, revert the transform right after we decode the data.
+    if (!StoreValues(num_values)) {
+      return false;
+    }
+  }
+#endif
+  return true;
+}
+
+std::unique_ptr<PredictionSchemeTypedDecoderInterface<int32_t>>
+SequentialIntegerAttributeDecoder::CreateIntPredictionScheme(
+    PredictionSchemeMethod method,
+    PredictionSchemeTransformType transform_type) {
+  if (transform_type != PREDICTION_TRANSFORM_WRAP) {
+    return nullptr;  // For now we support only wrap transform.
+  }
+  return CreatePredictionSchemeForDecoder<
+      int32_t, PredictionSchemeWrapDecodingTransform<int32_t>>(
+      method, attribute_id(), decoder());
+}
+
+bool SequentialIntegerAttributeDecoder::DecodeIntegerValues(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  const int num_components = GetNumValueComponents();
+  if (num_components <= 0) {
+    return false;
+  }
+  const size_t num_entries = point_ids.size();
+  const size_t num_values = num_entries * num_components;
+  PreparePortableAttribute(static_cast<int>(num_entries), num_components);
+  int32_t *const portable_attribute_data = GetPortableAttributeData();
+  if (portable_attribute_data == nullptr) {
+    return false;
+  }
+  uint8_t compressed;
+  if (!in_buffer->Decode(&compressed)) {
+    return false;
+  }
+  if (compressed > 0) {
+    // Decode compressed values.
+    if (!DecodeSymbols(static_cast<uint32_t>(num_values), num_components,
+                       in_buffer,
+                       reinterpret_cast<uint32_t *>(portable_attribute_data))) {
+      return false;
+    }
+  } else {
+    // Decode the integer data directly.
+    // Get the number of bytes for a given entry.
+    uint8_t num_bytes;
+    if (!in_buffer->Decode(&num_bytes)) {
+      return false;
+    }
+    if (num_bytes == DataTypeLength(DT_INT32)) {
+      if (portable_attribute()->buffer()->data_size() <
+          sizeof(int32_t) * num_values) {
+        return false;
+      }
+      if (!in_buffer->Decode(portable_attribute_data,
+                             sizeof(int32_t) * num_values)) {
+        return false;
+      }
+    } else {
+      if (portable_attribute()->buffer()->data_size() <
+          num_bytes * num_values) {
+        return false;
+      }
+      if (in_buffer->remaining_size() <
+          static_cast<int64_t>(num_bytes) * static_cast<int64_t>(num_values)) {
+        return false;
+      }
+      for (size_t i = 0; i < num_values; ++i) {
+        if (!in_buffer->Decode(portable_attribute_data + i, num_bytes))
+          return false;
+      }
+    }
+  }
+
+  if (num_values > 0 && (prediction_scheme_ == nullptr ||
+                         !prediction_scheme_->AreCorrectionsPositive())) {
+    // Convert the values back to the original signed format.
+    ConvertSymbolsToSignedInts(
+        reinterpret_cast<const uint32_t *>(portable_attribute_data),
+        static_cast<int>(num_values), portable_attribute_data);
+  }
+
+  // If the data was encoded with a prediction scheme, we must revert it.
+  if (prediction_scheme_) {
+    if (!prediction_scheme_->DecodePredictionData(in_buffer)) {
+      return false;
+    }
+
+    if (num_values > 0) {
+      if (!prediction_scheme_->ComputeOriginalValues(
+              portable_attribute_data, portable_attribute_data,
+              static_cast<int>(num_values), num_components, point_ids.data())) {
+        return false;
+      }
+    }
+  }
+  return true;
+}
+
+bool SequentialIntegerAttributeDecoder::StoreValues(uint32_t num_values) {
+  switch (attribute()->data_type()) {
+    case DT_UINT8:
+      StoreTypedValues<uint8_t>(num_values);
+      break;
+    case DT_INT8:
+      StoreTypedValues<int8_t>(num_values);
+      break;
+    case DT_UINT16:
+      StoreTypedValues<uint16_t>(num_values);
+      break;
+    case DT_INT16:
+      StoreTypedValues<int16_t>(num_values);
+      break;
+    case DT_UINT32:
+      StoreTypedValues<uint32_t>(num_values);
+      break;
+    case DT_INT32:
+      StoreTypedValues<int32_t>(num_values);
+      break;
+    default:
+      return false;
+  }
+  return true;
+}
+
+template <typename AttributeTypeT>
+void SequentialIntegerAttributeDecoder::StoreTypedValues(uint32_t num_values) {
+  const int num_components = attribute()->num_components();
+  const int entry_size = sizeof(AttributeTypeT) * num_components;
+  const std::unique_ptr<AttributeTypeT[]> att_val(
+      new AttributeTypeT[num_components]);
+  const int32_t *const portable_attribute_data = GetPortableAttributeData();
+  int val_id = 0;
+  int out_byte_pos = 0;
+  for (uint32_t i = 0; i < num_values; ++i) {
+    for (int c = 0; c < num_components; ++c) {
+      const AttributeTypeT value =
+          static_cast<AttributeTypeT>(portable_attribute_data[val_id++]);
+      att_val[c] = value;
+    }
+    // Store the integer value into the attribute buffer.
+    attribute()->buffer()->Write(out_byte_pos, att_val.get(), entry_size);
+    out_byte_pos += entry_size;
+  }
+}
+
+void SequentialIntegerAttributeDecoder::PreparePortableAttribute(
+    int num_entries, int num_components) {
+  GeometryAttribute va;
+  va.Init(attribute()->attribute_type(), nullptr, num_components, DT_INT32,
+          false, num_components * DataTypeLength(DT_INT32), 0);
+  std::unique_ptr<PointAttribute> port_att(new PointAttribute(va));
+  port_att->SetIdentityMapping();
+  port_att->Reset(num_entries);
+  SetPortableAttribute(std::move(port_att));
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_integer_attribute_decoder.h

@@ -0,0 +1,76 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_DECODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder.h"
+#include "draco/compression/attributes/sequential_attribute_decoder.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Decoder for attributes encoded with the SequentialIntegerAttributeEncoder.
+class SequentialIntegerAttributeDecoder : public SequentialAttributeDecoder {
+ public:
+  SequentialIntegerAttributeDecoder();
+  bool Init(PointCloudDecoder *decoder, int attribute_id) override;
+
+  bool TransformAttributeToOriginalFormat(
+      const std::vector<PointIndex> &point_ids) override;
+
+ protected:
+  bool DecodeValues(const std::vector<PointIndex> &point_ids,
+                    DecoderBuffer *in_buffer) override;
+  virtual bool DecodeIntegerValues(const std::vector<PointIndex> &point_ids,
+                                   DecoderBuffer *in_buffer);
+
+  // Returns a prediction scheme that should be used for decoding of the
+  // integer values.
+  virtual std::unique_ptr<PredictionSchemeTypedDecoderInterface<int32_t>>
+  CreateIntPredictionScheme(PredictionSchemeMethod method,
+                            PredictionSchemeTransformType transform_type);
+
+  // Returns the number of integer attribute components. In general, this
+  // can be different from the number of components of the input attribute.
+  virtual int32_t GetNumValueComponents() const {
+    return attribute()->num_components();
+  }
+
+  // Called after all integer values are decoded. The implementation should
+  // use this method to store the values into the attribute.
+  virtual bool StoreValues(uint32_t num_values);
+
+  void PreparePortableAttribute(int num_entries, int num_components);
+
+  int32_t *GetPortableAttributeData() {
+    if (portable_attribute()->size() == 0) {
+      return nullptr;
+    }
+    return reinterpret_cast<int32_t *>(
+        portable_attribute()->GetAddress(AttributeValueIndex(0)));
+  }
+
+ private:
+  // Stores decoded values into the attribute with a data type AttributeTypeT.
+  template <typename AttributeTypeT>
+  void StoreTypedValues(uint32_t num_values);
+
+  std::unique_ptr<PredictionSchemeTypedDecoderInterface<int32_t>>
+      prediction_scheme_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_integer_attribute_encoder.cc

@@ -0,0 +1,233 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_integer_attribute_encoder.h"
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_wrap_encoding_transform.h"
+#include "draco/compression/entropy/symbol_encoding.h"
+#include "draco/core/bit_utils.h"
+
+namespace draco {
+
+SequentialIntegerAttributeEncoder::SequentialIntegerAttributeEncoder() {}
+
+bool SequentialIntegerAttributeEncoder::Init(PointCloudEncoder *encoder,
+                                             int attribute_id) {
+  if (!SequentialAttributeEncoder::Init(encoder, attribute_id)) {
+    return false;
+  }
+  if (GetUniqueId() == SEQUENTIAL_ATTRIBUTE_ENCODER_INTEGER) {
+    // When encoding integers, this encoder currently works only for integer
+    // attributes up to 32 bits.
+    switch (attribute()->data_type()) {
+      case DT_INT8:
+      case DT_UINT8:
+      case DT_INT16:
+      case DT_UINT16:
+      case DT_INT32:
+      case DT_UINT32:
+        break;
+      default:
+        return false;
+    }
+  }
+  // Init prediction scheme.
+  const PredictionSchemeMethod prediction_scheme_method =
+      GetPredictionMethodFromOptions(attribute_id, *encoder->options());
+
+  prediction_scheme_ = CreateIntPredictionScheme(prediction_scheme_method);
+
+  if (prediction_scheme_ && !InitPredictionScheme(prediction_scheme_.get())) {
+    prediction_scheme_ = nullptr;
+  }
+
+  return true;
+}
+
+bool SequentialIntegerAttributeEncoder::TransformAttributeToPortableFormat(
+    const std::vector<PointIndex> &point_ids) {
+  if (encoder()) {
+    if (!PrepareValues(point_ids, encoder()->point_cloud()->num_points())) {
+      return false;
+    }
+  } else {
+    if (!PrepareValues(point_ids, 0)) {
+      return false;
+    }
+  }
+
+  // Update point to attribute mapping with the portable attribute if the
+  // attribute is a parent attribute (for now, we can skip it otherwise).
+  if (is_parent_encoder()) {
+    // First create map between original attribute value indices and new ones
+    // (determined by the encoding order).
+    const PointAttribute *const orig_att = attribute();
+    PointAttribute *const portable_att = portable_attribute();
+    IndexTypeVector<AttributeValueIndex, AttributeValueIndex>
+        value_to_value_map(orig_att->size());
+    for (int i = 0; i < point_ids.size(); ++i) {
+      value_to_value_map[orig_att->mapped_index(point_ids[i])] =
+          AttributeValueIndex(i);
+    }
+    if (portable_att->is_mapping_identity()) {
+      portable_att->SetExplicitMapping(encoder()->point_cloud()->num_points());
+    }
+    // Go over all points of the original attribute and update the mapping in
+    // the portable attribute.
+    for (PointIndex i(0); i < encoder()->point_cloud()->num_points(); ++i) {
+      portable_att->SetPointMapEntry(
+          i, value_to_value_map[orig_att->mapped_index(i)]);
+    }
+  }
+  return true;
+}
+
+std::unique_ptr<PredictionSchemeTypedEncoderInterface<int32_t>>
+SequentialIntegerAttributeEncoder::CreateIntPredictionScheme(
+    PredictionSchemeMethod method) {
+  return CreatePredictionSchemeForEncoder<
+      int32_t, PredictionSchemeWrapEncodingTransform<int32_t>>(
+      method, attribute_id(), encoder());
+}
+
+bool SequentialIntegerAttributeEncoder::EncodeValues(
+    const std::vector<PointIndex> &point_ids, EncoderBuffer *out_buffer) {
+  // Initialize general quantization data.
+  const PointAttribute *const attrib = attribute();
+  if (attrib->size() == 0) {
+    return true;
+  }
+
+  int8_t prediction_scheme_method = PREDICTION_NONE;
+  if (prediction_scheme_) {
+    if (!SetPredictionSchemeParentAttributes(prediction_scheme_.get())) {
+      return false;
+    }
+    prediction_scheme_method =
+        static_cast<int8_t>(prediction_scheme_->GetPredictionMethod());
+  }
+  out_buffer->Encode(prediction_scheme_method);
+  if (prediction_scheme_) {
+    out_buffer->Encode(
+        static_cast<int8_t>(prediction_scheme_->GetTransformType()));
+  }
+
+  const int num_components = portable_attribute()->num_components();
+  const int num_values =
+      static_cast<int>(num_components * portable_attribute()->size());
+  const int32_t *const portable_attribute_data = GetPortableAttributeData();
+
+  // We need to keep the portable data intact, but several encoding steps can
+  // result in changes of this data, e.g., by applying prediction schemes that
+  // change the data in place. To preserve the portable data we store and
+  // process all encoded data in a separate array.
+  std::vector<int32_t> encoded_data(num_values);
+
+  // All integer values are initialized. Process them using the prediction
+  // scheme if we have one.
+  if (prediction_scheme_) {
+    prediction_scheme_->ComputeCorrectionValues(
+        portable_attribute_data, &encoded_data[0], num_values, num_components,
+        point_ids.data());
+  }
+
+  if (prediction_scheme_ == nullptr ||
+      !prediction_scheme_->AreCorrectionsPositive()) {
+    const int32_t *const input =
+        prediction_scheme_ ? encoded_data.data() : portable_attribute_data;
+    ConvertSignedIntsToSymbols(input, num_values,
+                               reinterpret_cast<uint32_t *>(&encoded_data[0]));
+  }
+
+  if (encoder() == nullptr || encoder()->options()->GetGlobalBool(
+                                  "use_built_in_attribute_compression", true)) {
+    out_buffer->Encode(static_cast<uint8_t>(1));
+    Options symbol_encoding_options;
+    if (encoder() != nullptr) {
+      SetSymbolEncodingCompressionLevel(&symbol_encoding_options,
+                                        10 - encoder()->options()->GetSpeed());
+    }
+    if (!EncodeSymbols(reinterpret_cast<uint32_t *>(encoded_data.data()),
+                       static_cast<int>(point_ids.size()) * num_components,
+                       num_components, &symbol_encoding_options, out_buffer)) {
+      return false;
+    }
+  } else {
+    // No compression. Just store the raw integer values, using the number of
+    // bytes as needed.
+
+    // To compute the maximum bit-length, first OR all values.
+    uint32_t masked_value = 0;
+    for (uint32_t i = 0; i < static_cast<uint32_t>(num_values); ++i) {
+      masked_value |= encoded_data[i];
+    }
+    // Compute the msb of the ORed value.
+    int value_msb_pos = 0;
+    if (masked_value != 0) {
+      value_msb_pos = MostSignificantBit(masked_value);
+    }
+    const int num_bytes = 1 + value_msb_pos / 8;
+
+    out_buffer->Encode(static_cast<uint8_t>(0));
+    out_buffer->Encode(static_cast<uint8_t>(num_bytes));
+
+    if (num_bytes == DataTypeLength(DT_INT32)) {
+      out_buffer->Encode(encoded_data.data(), sizeof(int32_t) * num_values);
+    } else {
+      for (uint32_t i = 0; i < static_cast<uint32_t>(num_values); ++i) {
+        out_buffer->Encode(encoded_data.data() + i, num_bytes);
+      }
+    }
+  }
+  if (prediction_scheme_) {
+    prediction_scheme_->EncodePredictionData(out_buffer);
+  }
+  return true;
+}
+
+bool SequentialIntegerAttributeEncoder::PrepareValues(
+    const std::vector<PointIndex> &point_ids, int num_points) {
+  // Convert all values to int32_t format.
+  const PointAttribute *const attrib = attribute();
+  const int num_components = attrib->num_components();
+  const int num_entries = static_cast<int>(point_ids.size());
+  PreparePortableAttribute(num_entries, num_components, num_points);
+  int32_t dst_index = 0;
+  int32_t *const portable_attribute_data = GetPortableAttributeData();
+  for (PointIndex pi : point_ids) {
+    const AttributeValueIndex att_id = attrib->mapped_index(pi);
+    if (!attrib->ConvertValue<int32_t>(att_id,
+                                       portable_attribute_data + dst_index)) {
+      return false;
+    }
+    dst_index += num_components;
+  }
+  return true;
+}
+
+void SequentialIntegerAttributeEncoder::PreparePortableAttribute(
+    int num_entries, int num_components, int num_points) {
+  GeometryAttribute va;
+  va.Init(attribute()->attribute_type(), nullptr, num_components, DT_INT32,
+          false, num_components * DataTypeLength(DT_INT32), 0);
+  std::unique_ptr<PointAttribute> port_att(new PointAttribute(va));
+  port_att->Reset(num_entries);
+  SetPortableAttribute(std::move(port_att));
+  if (num_points) {
+    portable_attribute()->SetExplicitMapping(num_points);
+  }
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_integer_attribute_encoder.h

@@ -0,0 +1,67 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_ENCODER_H_
+
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder.h"
+#include "draco/compression/attributes/sequential_attribute_encoder.h"
+
+namespace draco {
+
+// Attribute encoder designed for lossless encoding of integer attributes. The
+// attribute values can be pre-processed by a prediction scheme and compressed
+// with a built-in entropy coder.
+class SequentialIntegerAttributeEncoder : public SequentialAttributeEncoder {
+ public:
+  SequentialIntegerAttributeEncoder();
+  uint8_t GetUniqueId() const override {
+    return SEQUENTIAL_ATTRIBUTE_ENCODER_INTEGER;
+  }
+
+  bool Init(PointCloudEncoder *encoder, int attribute_id) override;
+  bool TransformAttributeToPortableFormat(
+      const std::vector<PointIndex> &point_ids) override;
+
+ protected:
+  bool EncodeValues(const std::vector<PointIndex> &point_ids,
+                    EncoderBuffer *out_buffer) override;
+
+  // Returns a prediction scheme that should be used for encoding of the
+  // integer values.
+  virtual std::unique_ptr<PredictionSchemeTypedEncoderInterface<int32_t>>
+  CreateIntPredictionScheme(PredictionSchemeMethod method);
+
+  // Prepares the integer values that are going to be encoded.
+  virtual bool PrepareValues(const std::vector<PointIndex> &point_ids,
+                             int num_points);
+
+  void PreparePortableAttribute(int num_entries, int num_components,
+                                int num_points);
+
+  int32_t *GetPortableAttributeData() {
+    return reinterpret_cast<int32_t *>(
+        portable_attribute()->GetAddress(AttributeValueIndex(0)));
+  }
+
+ private:
+  // Optional prediction scheme can be used to modify the integer values in
+  // order to make them easier to compress.
+  std::unique_ptr<PredictionSchemeTypedEncoderInterface<int32_t>>
+      prediction_scheme_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_INTEGER_ATTRIBUTE_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_integer_attribute_encoding_test.cc

@@ -0,0 +1,64 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include <numeric>
+
+#include "draco/compression/attributes/sequential_integer_attribute_decoder.h"
+#include "draco/compression/attributes/sequential_integer_attribute_encoder.h"
+#include "draco/compression/config/compression_shared.h"
+#include "draco/core/draco_test_base.h"
+
+namespace draco {
+
+class SequentialIntegerAttributeEncodingTest : public ::testing::Test {
+ protected:
+};
+
+TEST_F(SequentialIntegerAttributeEncodingTest, DoesCompress) {
+  // This test verifies that IntegerEncoding encodes and decodes the given data.
+  const std::vector<int32_t> values{1,   8,  7,  5, 5,   5, 9,
+                                    155, -6, -9, 9, 125, 1, 0};
+  PointAttribute pa;
+  pa.Init(GeometryAttribute::GENERIC, 1, DT_INT32, false, values.size());
+  for (uint32_t i = 0; i < values.size(); ++i) {
+    pa.SetAttributeValue(AttributeValueIndex(i), &values[i]);
+  }
+  // List of point ids from 0 to point_ids.size() - 1.
+  std::vector<PointIndex> point_ids(values.size());
+  std::iota(point_ids.begin(), point_ids.end(), 0);
+
+  EncoderBuffer out_buf;
+  SequentialIntegerAttributeEncoder ie;
+  ASSERT_TRUE(ie.InitializeStandalone(&pa));
+  ASSERT_TRUE(ie.TransformAttributeToPortableFormat(point_ids));
+  ASSERT_TRUE(ie.EncodePortableAttribute(point_ids, &out_buf));
+  ASSERT_TRUE(ie.EncodeDataNeededByPortableTransform(&out_buf));
+
+  DecoderBuffer in_buf;
+  in_buf.Init(out_buf.data(), out_buf.size());
+  in_buf.set_bitstream_version(kDracoMeshBitstreamVersion);
+  SequentialIntegerAttributeDecoder id;
+  ASSERT_TRUE(id.InitializeStandalone(&pa));
+  ASSERT_TRUE(id.DecodePortableAttribute(point_ids, &in_buf));
+  ASSERT_TRUE(id.DecodeDataNeededByPortableTransform(point_ids, &in_buf));
+  ASSERT_TRUE(id.TransformAttributeToOriginalFormat(point_ids));
+
+  for (uint32_t i = 0; i < values.size(); ++i) {
+    int32_t entry_val;
+    pa.GetValue(AttributeValueIndex(i), &entry_val);
+    ASSERT_EQ(entry_val, values[i]);
+  }
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_normal_attribute_decoder.cc

@@ -0,0 +1,76 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_normal_attribute_decoder.h"
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+
+namespace draco {
+
+SequentialNormalAttributeDecoder::SequentialNormalAttributeDecoder() {}
+
+bool SequentialNormalAttributeDecoder::Init(PointCloudDecoder *decoder,
+                                            int attribute_id) {
+  if (!SequentialIntegerAttributeDecoder::Init(decoder, attribute_id)) {
+    return false;
+  }
+  // Currently, this encoder works only for 3-component normal vectors.
+  if (attribute()->num_components() != 3) {
+    return false;
+  }
+  // Also the data type must be DT_FLOAT32.
+  if (attribute()->data_type() != DT_FLOAT32) {
+    return false;
+  }
+  return true;
+}
+
+bool SequentialNormalAttributeDecoder::DecodeIntegerValues(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (decoder()->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 0)) {
+    // Note: in older bitstreams, we do not have a PortableAttribute() decoded
+    // at this stage so we cannot pass it down to the DecodeParameters() call.
+    // It still works fine for octahedral transform because it does not need to
+    // use any data from the attribute.
+    if (!octahedral_transform_.DecodeParameters(*attribute(), in_buffer)) {
+      return false;
+    }
+  }
+#endif
+  return SequentialIntegerAttributeDecoder::DecodeIntegerValues(point_ids,
+                                                                in_buffer);
+}
+
+bool SequentialNormalAttributeDecoder::DecodeDataNeededByPortableTransform(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  if (decoder()->bitstream_version() >= DRACO_BITSTREAM_VERSION(2, 0)) {
+    // For newer file version, decode attribute transform data here.
+    if (!octahedral_transform_.DecodeParameters(*GetPortableAttribute(),
+                                                in_buffer)) {
+      return false;
+    }
+  }
+
+  // Store the decoded transform data in portable attribute.
+  return octahedral_transform_.TransferToAttribute(portable_attribute());
+}
+
+bool SequentialNormalAttributeDecoder::StoreValues(uint32_t num_points) {
+  // Convert all quantized values back to floats.
+  return octahedral_transform_.InverseTransformAttribute(
+      *GetPortableAttribute(), attribute());
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_normal_attribute_decoder.h

@@ -0,0 +1,83 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_DECODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_DECODER_H_
+
+#include "draco/attributes/attribute_octahedron_transform.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_decoder_factory.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_decoding_transform.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_decoding_transform.h"
+#include "draco/compression/attributes/sequential_integer_attribute_decoder.h"
+#include "draco/draco_features.h"
+
+namespace draco {
+
+// Decoder for attributes encoded with SequentialNormalAttributeEncoder.
+class SequentialNormalAttributeDecoder
+    : public SequentialIntegerAttributeDecoder {
+ public:
+  SequentialNormalAttributeDecoder();
+  bool Init(PointCloudDecoder *decoder, int attribute_id) override;
+
+ protected:
+  int32_t GetNumValueComponents() const override {
+    return 2;  // We quantize everything into two components.
+  }
+  bool DecodeIntegerValues(const std::vector<PointIndex> &point_ids,
+                           DecoderBuffer *in_buffer) override;
+  bool DecodeDataNeededByPortableTransform(
+      const std::vector<PointIndex> &point_ids,
+      DecoderBuffer *in_buffer) override;
+  bool StoreValues(uint32_t num_points) override;
+
+ private:
+  AttributeOctahedronTransform octahedral_transform_;
+
+  std::unique_ptr<PredictionSchemeTypedDecoderInterface<int32_t>>
+  CreateIntPredictionScheme(
+      PredictionSchemeMethod method,
+      PredictionSchemeTransformType transform_type) override {
+    switch (transform_type) {
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+      case PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON: {
+        typedef PredictionSchemeNormalOctahedronDecodingTransform<int32_t>
+            Transform;
+        // At this point the decoder has not read the quantization bits,
+        // which is why we must construct the transform by default.
+        // See Transform.DecodeTransformData for more details.
+        return CreatePredictionSchemeForDecoder<int32_t, Transform>(
+            method, attribute_id(), decoder());
+      }
+#endif
+      case PREDICTION_TRANSFORM_NORMAL_OCTAHEDRON_CANONICALIZED: {
+        typedef PredictionSchemeNormalOctahedronCanonicalizedDecodingTransform<
+            int32_t>
+            Transform;
+        // At this point the decoder has not read the quantization bits,
+        // which is why we must construct the transform by default.
+        // See Transform.DecodeTransformData for more details.
+        return CreatePredictionSchemeForDecoder<int32_t, Transform>(
+            method, attribute_id(), decoder());
+      }
+      default:
+        return nullptr;  // Currently, we support only octahedron transform and
+                         // octahedron transform canonicalized.
+    }
+  }
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_DECODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_normal_attribute_encoder.cc

@@ -0,0 +1,57 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_normal_attribute_encoder.h"
+
+#include "draco/compression/attributes/normal_compression_utils.h"
+
+namespace draco {
+
+bool SequentialNormalAttributeEncoder::Init(PointCloudEncoder *encoder,
+                                            int attribute_id) {
+  if (!SequentialIntegerAttributeEncoder::Init(encoder, attribute_id))
+    return false;
+  // Currently this encoder works only for 3-component normal vectors.
+  if (attribute()->num_components() != 3) {
+    return false;
+  }
+
+  // Initialize AttributeOctahedronTransform.
+  const int quantization_bits = encoder->options()->GetAttributeInt(
+      attribute_id, "quantization_bits", -1);
+  if (quantization_bits < 1) {
+    return false;
+  }
+  attribute_octahedron_transform_.SetParameters(quantization_bits);
+  return true;
+}
+
+bool SequentialNormalAttributeEncoder::EncodeDataNeededByPortableTransform(
+    EncoderBuffer *out_buffer) {
+  return attribute_octahedron_transform_.EncodeParameters(out_buffer);
+}
+
+bool SequentialNormalAttributeEncoder::PrepareValues(
+    const std::vector<PointIndex> &point_ids, int num_points) {
+  auto portable_att = attribute_octahedron_transform_.InitTransformedAttribute(
+      *(attribute()), point_ids.size());
+  if (!attribute_octahedron_transform_.TransformAttribute(
+          *(attribute()), point_ids, portable_att.get())) {
+    return false;
+  }
+  SetPortableAttribute(std::move(portable_att));
+  return true;
+}
+
+}  // namespace draco

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_normal_attribute_encoder.h

@@ -0,0 +1,82 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_ENCODER_H_
+#define DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_ENCODER_H_
+
+#include "draco/attributes/attribute_octahedron_transform.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.h"
+#include "draco/compression/attributes/prediction_schemes/prediction_scheme_normal_octahedron_canonicalized_encoding_transform.h"
+#include "draco/compression/attributes/sequential_integer_attribute_encoder.h"
+#include "draco/compression/config/compression_shared.h"
+
+namespace draco {
+
+// Class for encoding normal vectors using an octahedral encoding, see Cigolle
+// et al.'14 “A Survey of Efficient Representations for Independent Unit
+// Vectors”. Compared to the basic quantization encoder, this encoder results
+// in a better compression rate under the same accuracy settings. Note that this
+// encoder doesn't preserve the lengths of input vectors, therefore it will not
+// work correctly when the input values are not normalized.
+class SequentialNormalAttributeEncoder
+    : public SequentialIntegerAttributeEncoder {
+ public:
+  uint8_t GetUniqueId() const override {
+    return SEQUENTIAL_ATTRIBUTE_ENCODER_NORMALS;
+  }
+  bool IsLossyEncoder() const override { return true; }
+
+  bool EncodeDataNeededByPortableTransform(EncoderBuffer *out_buffer) override;
+
+ protected:
+  bool Init(PointCloudEncoder *encoder, int attribute_id) override;
+
+  // Put quantized values in portable attribute for sequential encoding.
+  bool PrepareValues(const std::vector<PointIndex> &point_ids,
+                     int num_points) override;
+
+  std::unique_ptr<PredictionSchemeTypedEncoderInterface<int32_t>>
+  CreateIntPredictionScheme(PredictionSchemeMethod /* method */) override {
+    typedef PredictionSchemeNormalOctahedronCanonicalizedEncodingTransform<
+        int32_t>
+        Transform;
+    const int32_t quantization_bits = encoder()->options()->GetAttributeInt(
+        attribute_id(), "quantization_bits", -1);
+    const int32_t max_value = (1 << quantization_bits) - 1;
+    const Transform transform(max_value);
+    const PredictionSchemeMethod default_prediction_method =
+        SelectPredictionMethod(attribute_id(), encoder());
+    const int32_t prediction_method = encoder()->options()->GetAttributeInt(
+        attribute_id(), "prediction_scheme", default_prediction_method);
+
+    if (prediction_method == MESH_PREDICTION_GEOMETRIC_NORMAL) {
+      return CreatePredictionSchemeForEncoder<int32_t, Transform>(
+          MESH_PREDICTION_GEOMETRIC_NORMAL, attribute_id(), encoder(),
+          transform);
+    }
+    if (prediction_method == PREDICTION_DIFFERENCE) {
+      return CreatePredictionSchemeForEncoder<int32_t, Transform>(
+          PREDICTION_DIFFERENCE, attribute_id(), encoder(), transform);
+    }
+    DRACO_DCHECK(false);  // Should never be reached.
+    return nullptr;
+  }
+
+  // Used for the conversion to quantized normals in octahedral format.
+  AttributeOctahedronTransform attribute_octahedron_transform_;
+};
+
+}  // namespace draco
+
+#endif  // DRACO_COMPRESSION_ATTRIBUTES_SEQUENTIAL_NORMAL_ATTRIBUTE_ENCODER_H_

Engine/lib/assimp/contrib/draco/src/draco/compression/attributes/sequential_quantization_attribute_decoder.cc

@@ -0,0 +1,88 @@
+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#include "draco/compression/attributes/sequential_quantization_attribute_decoder.h"
+
+#include "draco/core/quantization_utils.h"
+
+namespace draco {
+
+SequentialQuantizationAttributeDecoder::
+    SequentialQuantizationAttributeDecoder() {}
+
+bool SequentialQuantizationAttributeDecoder::Init(PointCloudDecoder *decoder,
+                                                  int attribute_id) {
+  if (!SequentialIntegerAttributeDecoder::Init(decoder, attribute_id)) {
+    return false;
+  }
+  const PointAttribute *const attribute =
+      decoder->point_cloud()->attribute(attribute_id);
+  // Currently we can quantize only floating point arguments.
+  if (attribute->data_type() != DT_FLOAT32) {
+    return false;
+  }
+  return true;
+}
+
+bool SequentialQuantizationAttributeDecoder::DecodeIntegerValues(
+    const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+#ifdef DRACO_BACKWARDS_COMPATIBILITY_SUPPORTED
+  if (decoder()->bitstream_version() < DRACO_BITSTREAM_VERSION(2, 0) &&
+      !DecodeQuantizedDataInfo()) {
+    return false;
+  }
+#endif
+  return SequentialIntegerAttributeDecoder::DecodeIntegerValues(point_ids,
+                                                                in_buffer);
+}
+
+bool SequentialQuantizationAttributeDecoder::
+    DecodeDataNeededByPortableTransform(
+        const std::vector<PointIndex> &point_ids, DecoderBuffer *in_buffer) {
+  if (decoder()->bitstream_version() >= DRACO_BITSTREAM_VERSION(2, 0)) {
+    // Decode quantization data here only for files with bitstream version 2.0+
+    if (!DecodeQuantizedDataInfo()) {
+      return false;
+    }
+  }
+
+  // Store the decoded transform data in portable attribute;
+  return quantization_transform_.TransferToAttribute(portable_attribute());
+}
+
+bool SequentialQuantizationAttributeDecoder::StoreValues(uint32_t num_points) {
+  return DequantizeValues(num_points);
+}
+
+bool SequentialQuantizationAttributeDecoder::DecodeQuantizedDataInfo() {
+  // Get attribute used as source for decoding.
+  auto att = GetPortableAttribute();
+  if (att == nullptr) {
+    // This should happen only in the backward compatibility mode. It will still
+    // work fine for this case because the only thing the quantization transform
+    // cares about is the number of components that is the same for both source
+    // and target attributes.
+    att = attribute();
+  }
+  return quantization_transform_.DecodeParameters(*att, decoder()->buffer());
+}
+
+bool SequentialQuantizationAttributeDecoder::DequantizeValues(
+    uint32_t num_values) {
+  // Convert all quantized values back to floats.
+  return quantization_transform_.InverseTransformAttribute(
+      *GetPortableAttribute(), attribute());
+}
+
+}  // namespace draco