update assimp lib

Engine/lib/assimp/code/AssetLib/FBX/FBXConverter.cpp

@@ -2,7 +2,7 @@
 Open Asset Import Library (assimp)
 ----------------------------------------------------------------------
 
-Copyright (c) 2006-2022, assimp team
+Copyright (c) 2006-2024, assimp team
 
 All rights reserved.
 
@@ -55,9 +55,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <assimp/MathFunctions.h>
 #include <assimp/StringComparison.h>
-
 #include <assimp/scene.h>
-
 #include <assimp/CreateAnimMesh.h>
 #include <assimp/StringUtils.h>
 #include <assimp/commonMetaData.h>
@@ -78,6 +76,53 @@ using namespace Util;
 
 #define CONVERT_FBX_TIME(time) static_cast<double>(time) / 46186158000LL
 
+static void correctRootTransform(const aiScene *scene) {
+    if (scene == nullptr) {
+        return;
+    }
+
+    if (scene->mMetaData == nullptr) {
+        return;
+    }
+
+    int32_t UpAxis = 1, UpAxisSign = 1, FrontAxis = 2, FrontAxisSign = 1, CoordAxis = 0, CoordAxisSign = 1;
+    double UnitScaleFactor = 1.0;
+    for (unsigned MetadataIndex = 0; MetadataIndex < scene->mMetaData->mNumProperties; ++MetadataIndex) {
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "UpAxis") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, UpAxis);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "UpAxisSign") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, UpAxisSign);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "FrontAxis") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, FrontAxis);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "FrontAxisSign") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, FrontAxisSign);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "CoordAxis") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, CoordAxis);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "CoordAxisSign") == 0) {
+            scene->mMetaData->Get<int32_t>(MetadataIndex, CoordAxisSign);
+        }
+        if (strcmp(scene->mMetaData->mKeys[MetadataIndex].C_Str(), "UnitScaleFactor") == 0) {
+            scene->mMetaData->Get<double>(MetadataIndex, UnitScaleFactor);
+        }
+    }
+
+    aiVector3D upVec, forwardVec, rightVec;
+    upVec[UpAxis] = UpAxisSign * static_cast<float>(UnitScaleFactor);
+    forwardVec[FrontAxis] = FrontAxisSign * static_cast<float>(UnitScaleFactor);
+    rightVec[CoordAxis] = CoordAxisSign * (float)UnitScaleFactor;
+
+    aiMatrix4x4 mat(rightVec.x, rightVec.y, rightVec.z, 0.0f,
+                    upVec.x, upVec.y, upVec.z, 0.0f,
+                    forwardVec.x, forwardVec.y, forwardVec.z, 0.0f,
+                    0.0f, 0.0f, 0.0f, 1.0f);
+    scene->mRootNode->mTransformation *= mat;
+}
+
 FBXConverter::FBXConverter(aiScene *out, const Document &doc, bool removeEmptyBones) :
         defaultMaterialIndex(),
         mMeshes(),
@@ -93,6 +138,8 @@ FBXConverter::FBXConverter(aiScene *out, const Document &doc, bool removeEmptyBo
         mSceneOut(out),
         doc(doc),
         mRemoveEmptyBones(removeEmptyBones) {
+
+
     // animations need to be converted first since this will
     // populate the node_anim_chain_bits map, which is needed
     // to determine which nodes need to be generated.
@@ -119,7 +166,7 @@ FBXConverter::FBXConverter(aiScene *out, const Document &doc, bool removeEmptyBo
             if (mat) {
 
                 if (materials_converted.find(mat) == materials_converted.end()) {
-                    ConvertMaterial(*mat, 0);
+                    ConvertMaterial(*mat, nullptr);
                 }
             }
         }
@@ -133,6 +180,10 @@ FBXConverter::FBXConverter(aiScene *out, const Document &doc, bool removeEmptyBo
     // need not contain geometry (i.e. camera animations, raw armatures).
     if (out->mNumMeshes == 0) {
         out->mFlags |= AI_SCENE_FLAGS_INCOMPLETE;
+    } else {
+        // Apply the FBX axis metadata unless requested not to
+        if (!doc.Settings().ignoreUpDirection)
+            correctRootTransform(mSceneOut);
     }
 }
 
@@ -196,7 +247,7 @@ struct FBXConverter::PotentialNode {
 /// todo: get bone from stack
 /// todo: make map of aiBone* to aiNode*
 /// then update convert clusters to the new format
-void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node) {
+void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node, const aiMatrix4x4& parent_transform) {
     const std::vector<const Connection *> &conns = doc.GetConnectionsByDestinationSequenced(id, "Model");
 
     std::vector<PotentialNode> nodes;
@@ -227,7 +278,7 @@ void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node)
         if (nullptr != model) {
             nodes_chain.clear();
             post_nodes_chain.clear();
-            aiMatrix4x4 new_abs_transform = parent->mTransformation;
+            aiMatrix4x4 new_abs_transform = parent_transform;
             std::string node_name = FixNodeName(model->Name());
             // even though there is only a single input node, the design of
             // assimp (or rather: the complicated transformation chain that
@@ -261,6 +312,8 @@ void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node)
 
                 child->mParent = last_parent;
                 last_parent = child.mNode;
+
+                new_abs_transform *= child->mTransformation;
             }
 
             // attach geometry
@@ -283,6 +336,8 @@ void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node)
 
                     postnode->mParent = last_parent;
                     last_parent = postnode.mNode;
+
+                    new_abs_transform *= postnode->mTransformation;
                 }
             } else {
                 // free the nodes we allocated as we don't need them
@@ -290,7 +345,7 @@ void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node)
             }
 
             // recursion call - child nodes
-            ConvertNodes(model->ID(), last_parent, root_node);
+            ConvertNodes(model->ID(), last_parent, root_node, new_abs_transform);
 
             if (doc.Settings().readLights) {
                 ConvertLights(*model, node_name);
@@ -305,18 +360,15 @@ void FBXConverter::ConvertNodes(uint64_t id, aiNode *parent, aiNode *root_node)
         }
     }
 
-    if (nodes.size()) {
-        parent->mChildren = new aiNode *[nodes.size()]();
-        parent->mNumChildren = static_cast<unsigned int>(nodes.size());
-
-        for (unsigned int i = 0; i < nodes.size(); ++i)
-        {
-            parent->mChildren[i] = nodes[i].mOwnership.release();
-        }
-        nodes.clear();
-    } else {
+    if (nodes.empty()) {
         parent->mNumChildren = 0;
         parent->mChildren = nullptr;
+    } else {
+        parent->mChildren = new aiNode *[nodes.size()]();
+        parent->mNumChildren = static_cast<unsigned int>(nodes.size());
+        for (unsigned int i = 0; i < nodes.size(); ++i) {
+            parent->mChildren[i] = nodes[i].mOwnership.release();
+        }
     }
 }
 
@@ -424,16 +476,32 @@ void FBXConverter::ConvertCamera(const Camera &cam, const std::string &orig_name
 
     out_camera->mAspect = cam.AspectWidth() / cam.AspectHeight();
 
+    // NOTE: Camera mPosition, mLookAt and mUp must be set to default here.
+    // All transformations to the camera will be handled by its node in the scenegraph.
     out_camera->mPosition = aiVector3D(0.0f);
     out_camera->mLookAt = aiVector3D(1.0f, 0.0f, 0.0f);
     out_camera->mUp = aiVector3D(0.0f, 1.0f, 0.0f);
 
-    out_camera->mHorizontalFOV = AI_DEG_TO_RAD(cam.FieldOfView());
+    // NOTE: Some software (maya) does not put FieldOfView in FBX, so we compute
+    // mHorizontalFOV from FocalLength and FilmWidth with unit conversion.
 
-    out_camera->mClipPlaneNear = cam.NearPlane();
-    out_camera->mClipPlaneFar = cam.FarPlane();
+    // TODO: This is not a complete solution for how FBX cameras can be stored.
+    // TODO: Incorporate non-square pixel aspect ratio.
+    // TODO: FBX aperture mode might be storing vertical FOV in need of conversion with aspect ratio.
+
+    float fov_deg = cam.FieldOfView();
+    // If FOV not specified in file, compute using FilmWidth and FocalLength.
+    if (fov_deg == kFovUnknown) {
+        float film_width_inches = cam.FilmWidth();
+        float focal_length_mm = cam.FocalLength();
+        ASSIMP_LOG_VERBOSE_DEBUG("FBX FOV unspecified. Computing from FilmWidth (", film_width_inches, "inches) and FocalLength (", focal_length_mm, "mm).");
+        double half_fov_rad = std::atan2(film_width_inches * 25.4 * 0.5, focal_length_mm);
+        out_camera->mHorizontalFOV = static_cast<float>(half_fov_rad);
+    } else {
+        // FBX fov is full-view degrees. We want half-view radians.
+        out_camera->mHorizontalFOV = AI_DEG_TO_RAD(fov_deg) * 0.5f;
+    }
 
-    out_camera->mHorizontalFOV = AI_DEG_TO_RAD(cam.FieldOfView());
     out_camera->mClipPlaneNear = cam.NearPlane();
     out_camera->mClipPlaneFar = cam.FarPlane();
 }
@@ -562,16 +630,17 @@ void FBXConverter::GetRotationMatrix(Model::RotOrder mode, const aiVector3D &rot
     bool is_id[3] = { true, true, true };
 
     aiMatrix4x4 temp[3];
-    if (std::fabs(rotation.z) > angle_epsilon) {
-        aiMatrix4x4::RotationZ(AI_DEG_TO_RAD(rotation.z), temp[2]);
+    const auto rot = AI_DEG_TO_RAD(rotation);
+    if (std::fabs(rot.z) > angle_epsilon) {
+        aiMatrix4x4::RotationZ(rot.z, temp[2]);
         is_id[2] = false;
     }
-    if (std::fabs(rotation.y) > angle_epsilon) {
-        aiMatrix4x4::RotationY(AI_DEG_TO_RAD(rotation.y), temp[1]);
+    if (std::fabs(rot.y) > angle_epsilon) {
+        aiMatrix4x4::RotationY(rot.y, temp[1]);
         is_id[1] = false;
     }
-    if (std::fabs(rotation.x) > angle_epsilon) {
-        aiMatrix4x4::RotationX(AI_DEG_TO_RAD(rotation.x), temp[0]);
+    if (std::fabs(rot.x) > angle_epsilon) {
+        aiMatrix4x4::RotationX(rot.x, temp[0]);
         is_id[0] = false;
     }
 
@@ -643,13 +712,12 @@ void FBXConverter::GetRotationMatrix(Model::RotOrder mode, const aiVector3D &rot
 bool FBXConverter::NeedsComplexTransformationChain(const Model &model) {
     const PropertyTable &props = model.Props();
 
-    const auto zero_epsilon = ai_epsilon;
+    const auto zero_epsilon = Math::getEpsilon<ai_real>();
     const aiVector3D all_ones(1.0f, 1.0f, 1.0f);
     for (size_t i = 0; i < TransformationComp_MAXIMUM; ++i) {
         const TransformationComp comp = static_cast<TransformationComp>(i);
 
-        if (comp == TransformationComp_Rotation || comp == TransformationComp_Scaling || comp == TransformationComp_Translation ||
-            comp == TransformationComp_PreRotation || comp == TransformationComp_PostRotation) {
+        if (comp == TransformationComp_Rotation || comp == TransformationComp_Scaling || comp == TransformationComp_Translation) {
             continue;
         }
 
@@ -876,8 +944,12 @@ void FBXConverter::SetupNodeMetadata(const Model &model, aiNode &nd) {
             data->Set(index++, prop.first, interpretedBool->Value());
         } else if (const TypedProperty<int> *interpretedInt = prop.second->As<TypedProperty<int>>()) {
             data->Set(index++, prop.first, interpretedInt->Value());
+        } else if (const TypedProperty<uint32_t> *interpretedUInt = prop.second->As<TypedProperty<uint32_t>>()) {
+            data->Set(index++, prop.first, interpretedUInt->Value());
         } else if (const TypedProperty<uint64_t> *interpretedUint64 = prop.second->As<TypedProperty<uint64_t>>()) {
             data->Set(index++, prop.first, interpretedUint64->Value());
+        } else if (const TypedProperty<int64_t> *interpretedint64 = prop.second->As<TypedProperty<int64_t>>()) {
+            data->Set(index++, prop.first, interpretedint64->Value());
         } else if (const TypedProperty<float> *interpretedFloat = prop.second->As<TypedProperty<float>>()) {
             data->Set(index++, prop.first, interpretedFloat->Value());
         } else if (const TypedProperty<std::string> *interpretedString = prop.second->As<TypedProperty<std::string>>()) {
@@ -1179,19 +1251,27 @@ unsigned int FBXConverter::ConvertMeshSingleMaterial(const MeshGeometry &mesh, c
     std::vector<aiAnimMesh *> animMeshes;
     for (const BlendShape *blendShape : mesh.GetBlendShapes()) {
         for (const BlendShapeChannel *blendShapeChannel : blendShape->BlendShapeChannels()) {
-            const std::vector<const ShapeGeometry *> &shapeGeometries = blendShapeChannel->GetShapeGeometries();
-            for (size_t i = 0; i < shapeGeometries.size(); i++) {
-                aiAnimMesh *animMesh = aiCreateAnimMesh(out_mesh);
-                const ShapeGeometry *shapeGeometry = shapeGeometries.at(i);
-                const std::vector<aiVector3D> &curVertices = shapeGeometry->GetVertices();
-                const std::vector<aiVector3D> &curNormals = shapeGeometry->GetNormals();
-                const std::vector<unsigned int> &curIndices = shapeGeometry->GetIndices();
+            const auto& shapeGeometries = blendShapeChannel->GetShapeGeometries();
+            for (const ShapeGeometry *shapeGeometry : shapeGeometries) {
+                const auto &curNormals = shapeGeometry->GetNormals();
+                aiAnimMesh *animMesh = aiCreateAnimMesh(out_mesh, true, !curNormals.empty());
+                const auto &curVertices = shapeGeometry->GetVertices();
+                const auto &curIndices = shapeGeometry->GetIndices();
                 //losing channel name if using shapeGeometry->Name()
-                animMesh->mName.Set(FixAnimMeshName(blendShapeChannel->Name()));
+                // if blendShapeChannel Name is empty or doesn't have a ".", add geoMetryName;
+                auto aniName = FixAnimMeshName(blendShapeChannel->Name());
+                auto geoMetryName = FixAnimMeshName(shapeGeometry->Name());
+                if (aniName.empty()) {
+                    aniName = geoMetryName;
+                }
+                else if (aniName.find('.') == aniName.npos) {
+                    aniName += "." + geoMetryName;
+                }
+                animMesh->mName.Set(aniName);
                 for (size_t j = 0; j < curIndices.size(); j++) {
                     const unsigned int curIndex = curIndices.at(j);
                     aiVector3D vertex = curVertices.at(j);
-                    aiVector3D normal = curNormals.at(j);
+                    aiVector3D normal = curNormals.empty() ? aiVector3D() : curNormals.at(j);
                     unsigned int count = 0;
                     const unsigned int *outIndices = mesh.ToOutputVertexIndex(curIndex, count);
                     for (unsigned int k = 0; k < count; k++) {
@@ -1409,18 +1489,17 @@ unsigned int FBXConverter::ConvertMeshMultiMaterial(const MeshGeometry &mesh, co
     std::vector<aiAnimMesh *> animMeshes;
     for (const BlendShape *blendShape : mesh.GetBlendShapes()) {
         for (const BlendShapeChannel *blendShapeChannel : blendShape->BlendShapeChannels()) {
-            const std::vector<const ShapeGeometry *> &shapeGeometries = blendShapeChannel->GetShapeGeometries();
-            for (size_t i = 0; i < shapeGeometries.size(); i++) {
-                aiAnimMesh *animMesh = aiCreateAnimMesh(out_mesh);
-                const ShapeGeometry *shapeGeometry = shapeGeometries.at(i);
-                const std::vector<aiVector3D> &curVertices = shapeGeometry->GetVertices();
-                const std::vector<aiVector3D> &curNormals = shapeGeometry->GetNormals();
-                const std::vector<unsigned int> &curIndices = shapeGeometry->GetIndices();
+            const auto& shapeGeometries = blendShapeChannel->GetShapeGeometries();
+            for (const ShapeGeometry *shapeGeometry : shapeGeometries) {
+                const auto& curNormals = shapeGeometry->GetNormals();
+                aiAnimMesh *animMesh = aiCreateAnimMesh(out_mesh, true, !curNormals.empty());
+                const auto& curVertices = shapeGeometry->GetVertices();
+                const auto& curIndices = shapeGeometry->GetIndices();
                 animMesh->mName.Set(FixAnimMeshName(shapeGeometry->Name()));
                 for (size_t j = 0; j < curIndices.size(); j++) {
                     unsigned int curIndex = curIndices.at(j);
                     aiVector3D vertex = curVertices.at(j);
-                    aiVector3D normal = curNormals.at(j);
+                    aiVector3D normal = curNormals.empty() ? aiVector3D() : curNormals.at(j);
                     unsigned int count = 0;
                     const unsigned int *outIndices = mesh.ToOutputVertexIndex(curIndex, count);
                     for (unsigned int k = 0; k < count; k++) {
@@ -1458,7 +1537,9 @@ static void copyBoneToSkeletonBone(aiMesh *mesh, aiBone *bone, aiSkeletonBone *s
     skeletonBone->mWeights = bone->mWeights;
     skeletonBone->mOffsetMatrix = bone->mOffsetMatrix;
     skeletonBone->mMeshId = mesh;
+#ifndef ASSIMP_BUILD_NO_ARMATUREPOPULATE_PROCESS
     skeletonBone->mNode = bone->mNode;
+#endif
     skeletonBone->mParent = -1;
 }
 
@@ -1566,7 +1647,7 @@ void FBXConverter::ConvertWeights(aiMesh *out, const MeshGeometry &geo, const ai
         out->mBones = nullptr;
         out->mNumBones = 0;
         return;
-    } 
+    }
 
     out->mBones = new aiBone *[bones.size()]();
     out->mNumBones = static_cast<unsigned int>(bones.size());
@@ -1575,7 +1656,7 @@ void FBXConverter::ConvertWeights(aiMesh *out, const MeshGeometry &geo, const ai
 
 void FBXConverter::ConvertCluster(std::vector<aiBone*> &local_mesh_bones, const Cluster *cluster,
         std::vector<size_t> &out_indices, std::vector<size_t> &index_out_indices,
-        std::vector<size_t> &count_out_indices, const aiMatrix4x4 & /* absolute_transform*/,
+        std::vector<size_t> &count_out_indices, const aiMatrix4x4 &absolute_transform,
         aiNode *) {
     ai_assert(cluster != nullptr); // make sure cluster valid
 
@@ -1592,16 +1673,16 @@ void FBXConverter::ConvertCluster(std::vector<aiBone*> &local_mesh_bones, const
         bone = new aiBone();
         bone->mName = bone_name;
 
-        bone->mOffsetMatrix = cluster->Transform();
+        //bone->mOffsetMatrix = cluster->Transform();
         // store local transform link for post processing
-        /*
+
         bone->mOffsetMatrix = cluster->TransformLink();
         bone->mOffsetMatrix.Inverse();
 
-        aiMatrix4x4 matrix = (aiMatrix4x4)absolute_transform;
+        const aiMatrix4x4 matrix = (aiMatrix4x4)absolute_transform;
 
         bone->mOffsetMatrix = bone->mOffsetMatrix * matrix; // * mesh_offset
-        */
+
         //
         // Now calculate the aiVertexWeights
         //
@@ -1784,7 +1865,7 @@ aiString FBXConverter::GetTexturePath(const Texture *tex) {
                 // We need to load all textures before referencing them, as FBX file format order may reference a texture before loading it
                 // This may occur on this case too, it has to be studied
                 path.data[0] = '*';
-                path.length = 1 + ASSIMP_itoa10(path.data + 1, MAXLEN - 1, index);
+                path.length = 1 + ASSIMP_itoa10(path.data + 1, AI_MAXLEN - 1, index);
             }
         }
     }
@@ -2052,6 +2133,10 @@ void FBXConverter::SetTextureProperties(aiMaterial *out_mat, const TextureMap &_
     TrySetTextureProperties(out_mat, _textures, "Maya|emissionColor", aiTextureType_EMISSION_COLOR, mesh);
     TrySetTextureProperties(out_mat, _textures, "Maya|metalness", aiTextureType_METALNESS, mesh);
     TrySetTextureProperties(out_mat, _textures, "Maya|diffuseRoughness", aiTextureType_DIFFUSE_ROUGHNESS, mesh);
+    TrySetTextureProperties(out_mat, _textures, "Maya|base", aiTextureType_MAYA_BASE, mesh);
+    TrySetTextureProperties(out_mat, _textures, "Maya|specular", aiTextureType_MAYA_SPECULAR, mesh);
+    TrySetTextureProperties(out_mat, _textures, "Maya|specularColor", aiTextureType_MAYA_SPECULAR_COLOR, mesh);
+    TrySetTextureProperties(out_mat, _textures, "Maya|specularRoughness", aiTextureType_MAYA_SPECULAR_ROUGHNESS, mesh);
 
     // Maya stingray
     TrySetTextureProperties(out_mat, _textures, "Maya|TEX_color_map", aiTextureType_BASE_COLOR, mesh);
@@ -2364,7 +2449,7 @@ void FBXConverter::SetShadingPropertiesRaw(aiMaterial *out_mat, const PropertyTa
 
                 // setup texture reference string (copied from ColladaLoader::FindFilenameForEffectTexture)
                 path.data[0] = '*';
-                path.length = 1 + ASSIMP_itoa10(path.data + 1, MAXLEN - 1, index);
+                path.length = 1 + ASSIMP_itoa10(path.data + 1, AI_MAXLEN - 1, index);
             }
 
             out_mat->AddProperty(&path, (name + "|file").c_str(), aiTextureType_UNKNOWN, 0);
@@ -2730,7 +2815,7 @@ void FBXConverter::ProcessMorphAnimDatas(std::map<std::string, morphAnimData *>
                                 auto geoIt = std::find(model->GetGeometry().begin(), model->GetGeometry().end(), geo);
                                 auto geoIndex = static_cast<unsigned int>(std::distance(model->GetGeometry().begin(), geoIt));
                                 auto name = aiString(FixNodeName(model->Name() + "*"));
-                                name.length = 1 + ASSIMP_itoa10(name.data + name.length, MAXLEN - 1, geoIndex);
+                                name.length = 1 + ASSIMP_itoa10(name.data + name.length, AI_MAXLEN - 1, geoIndex);
                                 morphAnimData *animData;
                                 auto animIt = morphAnimDatas->find(name.C_Str());
                                 if (animIt == morphAnimDatas->end()) {
@@ -3197,7 +3282,6 @@ aiNodeAnim* FBXConverter::GenerateSimpleNodeAnim(const std::string& name,
     aiVector3D defTranslate = PropertyGet(props, "Lcl Translation", aiVector3D(0.f, 0.f, 0.f));
     aiVector3D defRotation = PropertyGet(props, "Lcl Rotation", aiVector3D(0.f, 0.f, 0.f));
     aiVector3D defScale = PropertyGet(props, "Lcl Scaling", aiVector3D(1.f, 1.f, 1.f));
-    aiQuaternion defQuat = EulerToQuaternion(defRotation, rotOrder);
 
     aiVectorKey* outTranslations = new aiVectorKey[keyCount];
     aiQuatKey* outRotations = new aiQuatKey[keyCount];
@@ -3215,6 +3299,7 @@ aiNodeAnim* FBXConverter::GenerateSimpleNodeAnim(const std::string& name,
     if (keyframeLists[TransformationComp_Rotation].size() > 0) {
         InterpolateKeys(outRotations, keytimes, keyframeLists[TransformationComp_Rotation], defRotation, maxTime, minTime, rotOrder);
     } else {
+        aiQuaternion defQuat = EulerToQuaternion(defRotation, rotOrder);
         for (size_t i = 0; i < keyCount; ++i) {
             outRotations[i].mTime = CONVERT_FBX_TIME(keytimes[i]) * anim_fps;
             outRotations[i].mValue = defQuat;
@@ -3231,7 +3316,7 @@ aiNodeAnim* FBXConverter::GenerateSimpleNodeAnim(const std::string& name,
     }
 
     bool ok = false;
-    
+
     const auto zero_epsilon = ai_epsilon;
 
     const aiVector3D& preRotation = PropertyGet<aiVector3D>(props, "PreRotation", ok);