WIP of assimp integration.

Engine/lib/assimp/code/ObjExporter.h

@@ -0,0 +1,190 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2018, assimp team
+
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the
+following conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----------------------------------------------------------------------
+*/
+
+/** @file ObjExporter.h
+ * Declares the exporter class to write a scene to a Collada file
+ */
+#ifndef AI_OBJEXPORTER_H_INC
+#define AI_OBJEXPORTER_H_INC
+
+#include <assimp/types.h>
+#include <sstream>
+#include <vector>
+#include <map>
+
+struct aiScene;
+struct aiNode;
+struct aiMesh;
+
+namespace Assimp {
+
+// ------------------------------------------------------------------------------------------------
+/** Helper class to export a given scene to an OBJ file. */
+// ------------------------------------------------------------------------------------------------
+class ObjExporter {
+public:
+    /// Constructor for a specific scene to export
+    ObjExporter(const char* filename, const aiScene* pScene, bool noMtl=false);
+    ~ObjExporter();
+    std::string GetMaterialLibName();
+    std::string GetMaterialLibFileName();
+    
+    /// public string-streams to write all output into
+    std::ostringstream mOutput, mOutputMat;
+
+private:
+    // intermediate data structures
+    struct FaceVertex {
+        FaceVertex()
+        : vp()
+        , vn()
+        , vt() {
+            // empty
+        }
+
+        // one-based, 0 means: 'does not exist'
+        unsigned int vp, vn, vt;
+    };
+
+    struct Face {
+        char kind;
+        std::vector<FaceVertex> indices;
+    };
+
+    struct MeshInstance {
+        std::string name, matname;
+        std::vector<Face> faces;
+    };
+
+    void WriteHeader(std::ostringstream& out);
+    void WriteMaterialFile();
+    void WriteGeometryFile(bool noMtl=false);
+    std::string GetMaterialName(unsigned int index);
+    void AddMesh(const aiString& name, const aiMesh* m, const aiMatrix4x4& mat);
+    void AddNode(const aiNode* nd, const aiMatrix4x4& mParent);
+
+private:
+    std::string filename;
+    const aiScene* const pScene;
+
+    struct vertexData {
+        aiVector3D vp;
+        aiColor3D vc; // OBJ does not support 4D color
+    };
+
+    std::vector<aiVector3D> vn, vt;
+    std::vector<aiColor4D> vc;
+    std::vector<vertexData> vp;
+    bool useVc;
+
+    struct vertexDataCompare {
+        bool operator() ( const vertexData& a, const vertexData& b ) const {
+            // position
+            if (a.vp.x < b.vp.x) return true;
+            if (a.vp.x > b.vp.x) return false;
+            if (a.vp.y < b.vp.y) return true;
+            if (a.vp.y > b.vp.y) return false;
+            if (a.vp.z < b.vp.z) return true;
+            if (a.vp.z > b.vp.z) return false;
+
+            // color
+            if (a.vc.r < b.vc.r) return true;
+            if (a.vc.r > b.vc.r) return false;
+            if (a.vc.g < b.vc.g) return true;
+            if (a.vc.g > b.vc.g) return false;
+            if (a.vc.b < b.vc.b) return true;
+            if (a.vc.b > b.vc.b) return false;
+            return false;
+        }
+    };
+
+    struct aiVectorCompare { 
+        bool operator() (const aiVector3D& a, const aiVector3D& b) const { 
+            if(a.x < b.x) return true; 
+            if(a.x > b.x) return false; 
+            if(a.y < b.y) return true; 
+            if(a.y > b.y) return false; 
+            if(a.z < b.z) return true; 
+            return false;
+        }
+    };
+
+    template <class T, class Compare = std::less<T>>
+    class indexMap {
+        int mNextIndex;
+        typedef std::map<T, int, Compare> dataType;
+        dataType vecMap;
+    
+    public:
+        indexMap()
+        : mNextIndex(1) {
+            // empty
+        }
+
+        int getIndex(const T& key) {
+            typename dataType::iterator vertIt = vecMap.find(key);
+            // vertex already exists, so reference it
+            if(vertIt != vecMap.end()){
+                return vertIt->second;
+            }
+            return vecMap[key] = mNextIndex++;
+        };
+
+        void getKeys( std::vector<T>& keys ) {
+            keys.resize(vecMap.size());
+            for(typename dataType::iterator it = vecMap.begin(); it != vecMap.end(); ++it){
+                keys[it->second-1] = it->first;
+            }
+        };
+    };
+
+    indexMap<aiVector3D, aiVectorCompare> mVnMap, mVtMap;
+    indexMap<vertexData, vertexDataCompare> mVpMap;
+    std::vector<MeshInstance> mMeshes;
+
+    // this endl() doesn't flush() the stream
+    const std::string endl;
+};
+
+}
+
+#endif