Initial implementation of 3DS Exporter. Hierarchy exporting and smoothing groups missing.

code/3DSExporter.cpp

@@ -0,0 +1,498 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2012, 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.
+
+----------------------------------------------------------------------
+*/
+
+#include "AssimpPCH.h"
+
+#ifndef ASSIMP_BUILD_NO_EXPORT
+#ifndef ASSIMP_BUILD_NO_3DS_EXPORTER
+
+#include "3DSExporter.h"
+#include "3DSLoader.h"
+#include "SceneCombiner.h"
+#include "SplitLargeMeshes.h"
+
+using namespace Assimp;
+namespace Assimp	{
+
+namespace {
+
+	//////////////////////////////////////////////////////////////////////////////////////
+	// Scope utility to write a 3DS file chunk.
+	//
+	// Upon construction, the chunk header is written with the chunk type (flags)
+	// filled out, but the chunk size left empty. Upon destruction, the correct chunk
+	// size based on the then-position of the output stream cursor is filled in.
+	class ChunkWriter {
+		enum {
+			  CHUNK_SIZE_NOT_SET = 0xdeadbeef
+			, SIZE_OFFSET        = 2
+		};
+	public:
+
+		ChunkWriter(StreamWriterLE& writer, uint16_t chunk_type)
+			: writer(writer)
+		{
+			chunk_start_pos = writer.GetCurrentPos();
+			writer.PutU2(chunk_type);
+			writer.PutU4(CHUNK_SIZE_NOT_SET);
+		}
+
+		~ChunkWriter() {
+			std::size_t head_pos = writer.GetCurrentPos();
+
+			ai_assert(head_pos > chunk_start_pos);
+			const std::size_t chunk_size = head_pos - chunk_start_pos;
+
+			writer.SetCurrentPos(chunk_start_pos + SIZE_OFFSET);
+			writer.PutU4(chunk_size);
+			writer.SetCurrentPos(head_pos);
+		}
+		
+	private:
+		StreamWriterLE& writer;
+		std::size_t chunk_start_pos;
+	};
+
+
+	// Return an unique name for a given |mesh| attached to |node| that
+	// preserves the mesh's given name if it has one. |index| is the index
+	// of the mesh in |aiScene::mMeshes|.
+	std::string GetMeshName(const aiMesh& mesh, unsigned int index, const aiNode& node) {
+		static const std::string underscore = "_";
+		char postfix[10] = {0};
+		ASSIMP_itoa10(postfix, index);
+
+		std::string result = node.mName.C_Str();
+		if (mesh.mName.length > 0) {
+			result += underscore + mesh.mName.C_Str();
+		}
+		return result + underscore + postfix;
+	}
+
+	// Return an unique name for a given |mat| with original position |index|
+	// in |aiScene::mMaterials|. The name preserves the original material
+	// name if possible.
+	std::string GetMaterialName(const aiMaterial& mat, unsigned int index) {
+		static const std::string underscore = "_";
+		char postfix[10] = {0};
+		ASSIMP_itoa10(postfix, index);
+
+		aiString mat_name;
+		if (AI_SUCCESS == mat.Get(AI_MATKEY_NAME, mat_name)) {
+			return mat_name.C_Str() + underscore + postfix;
+		}
+
+		return "Material" + underscore + postfix;
+	}
+
+	// Collect world transformations for each node
+	void CollectTrafos(const aiNode* node, std::map<const aiNode*, aiMatrix4x4>& trafos) {
+		const aiMatrix4x4& parent = node->mParent ? trafos[node->mParent] : aiMatrix4x4();
+		trafos[node] = parent * node->mTransformation;
+		for (unsigned int i = 0; i < node->mNumChildren; ++i) {
+			CollectTrafos(node->mChildren[i], trafos);
+		}
+	}
+
+	// Generate a flat list of the meshes (by index) assigned to each node
+	void CollectMeshes(const aiNode* node, std::multimap<const aiNode*, unsigned int>& meshes) {
+		for (unsigned int i = 0; i < node->mNumMeshes; ++i) {
+			meshes.insert(std::make_pair(node, node->mMeshes[i]));
+		}
+		for (unsigned int i = 0; i < node->mNumChildren; ++i) {
+			CollectMeshes(node->mChildren[i], meshes);
+		}
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+// Worker function for exporting a scene to 3DS. Prototyped and registered in Exporter.cpp
+void ExportScene3DS(const char* pFile, IOSystem* pIOSystem, const aiScene* pScene)
+{
+	boost::shared_ptr<IOStream> outfile (pIOSystem->Open(pFile, "wb"));
+	if(outfile == NULL) {
+		throw DeadlyExportError("Could not open output .3ds file: " + std::string(pFile));
+	} 
+
+	// TODO: This extra copy should be avoided and all of this made a preprocess
+	// requirement of the 3DS exporter.
+	//
+	// 3DS meshes can be max 0xffff (16 Bit) vertices and faces, respectively.
+	// SplitLargeMeshes can do this, but it requires the correct limit to be set
+	// which is not possible with the current way of specifying preprocess steps
+	// in |Exporter::ExportFormatEntry|.
+	aiScene* scenecopy_tmp;
+	SceneCombiner::CopyScene(&scenecopy_tmp,pScene);
+	std::auto_ptr<aiScene> scenecopy(scenecopy_tmp);
+
+	SplitLargeMeshesProcess_Triangle tri_splitter;
+	tri_splitter.SetLimit(0xffff);
+	tri_splitter.Execute(scenecopy.get());
+
+	SplitLargeMeshesProcess_Vertex vert_splitter;
+	vert_splitter.SetLimit(0xffff);
+	vert_splitter.Execute(scenecopy.get());
+
+	// Invoke the actual exporter 
+	Discreet3DSExporter exporter(outfile, scenecopy.get());
+}
+
+} // end of namespace Assimp
+
+// ------------------------------------------------------------------------------------------------
+Discreet3DSExporter:: Discreet3DSExporter(boost::shared_ptr<IOStream> outfile, const aiScene* scene)
+: scene(scene)
+, writer(outfile)
+{
+	
+	CollectTrafos(scene->mRootNode, trafos);
+	CollectMeshes(scene->mRootNode, meshes);
+
+	ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAIN);
+
+	{
+		ChunkWriter chunk(writer, Discreet3DS::CHUNK_OBJMESH);
+		WriteMeshes();
+		WriteMaterials();
+	}
+
+	{
+		ChunkWriter chunk(writer, Discreet3DS::CHUNK_KEYFRAMER);
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteMaterials()
+{
+	for (unsigned int i = 0; i < scene->mNumMaterials; ++i) {
+		ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_MATERIAL);
+
+		const aiMaterial& mat = *scene->mMaterials[i];
+
+		{
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_MATNAME);
+			const std::string& name = GetMaterialName(mat, i);
+			WriteString(name);
+		}
+
+		aiColor3D color;
+		if (mat.Get(AI_MATKEY_COLOR_DIFFUSE, color) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_DIFFUSE);
+			WriteColor(color);
+		}
+
+		if (mat.Get(AI_MATKEY_COLOR_SPECULAR, color) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_SPECULAR);
+			WriteColor(color);
+		}
+
+		if (mat.Get(AI_MATKEY_COLOR_AMBIENT, color) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_AMBIENT);
+			WriteColor(color);
+		}
+
+		if (mat.Get(AI_MATKEY_COLOR_EMISSIVE, color) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_SELF_ILLUM);
+			WriteColor(color);
+		}
+
+		aiShadingMode shading_mode;
+		if (mat.Get(AI_MATKEY_SHADING_MODEL, shading_mode) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_SHADING);
+
+			Discreet3DS::shadetype3ds shading_mode_out;
+			switch(shading_mode) {
+			case aiShadingMode_Flat:
+			case aiShadingMode_NoShading:
+				shading_mode_out = Discreet3DS::Flat;
+				break;
+
+			case aiShadingMode_Gouraud:
+			case aiShadingMode_Toon:
+			case aiShadingMode_OrenNayar:
+			case aiShadingMode_Minnaert:
+				shading_mode_out = Discreet3DS::Gouraud;
+				break;
+
+			case aiShadingMode_Phong:
+			case aiShadingMode_Blinn:
+			case aiShadingMode_CookTorrance:
+			case aiShadingMode_Fresnel:
+				shading_mode_out = Discreet3DS::Phong;
+				break;
+
+			default:
+				ai_assert(false);
+			};
+			writer.PutU2(static_cast<uint16_t>(shading_mode_out));
+		}
+
+
+		float f;
+		if (mat.Get(AI_MATKEY_SHININESS, f) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_SHININESS);
+			WritePercentChunk(f);
+		}
+
+		if (mat.Get(AI_MATKEY_SHININESS_STRENGTH, f) == AI_SUCCESS) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_SHININESS_PERCENT);
+			WritePercentChunk(f);
+		}
+
+		int twosided;
+		if (mat.Get(AI_MATKEY_TWOSIDED, twosided) == AI_SUCCESS && twosided != 0) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAT_TWO_SIDE);
+			// Intentionally no more data - if the chunk exists, the TWOSIDED
+			// flag is assumed to be set.
+		}
+
+		WriteTexture(mat, aiTextureType_DIFFUSE, Discreet3DS::CHUNK_MAT_TEXTURE);
+		WriteTexture(mat, aiTextureType_HEIGHT, Discreet3DS::CHUNK_MAT_BUMPMAP);
+		WriteTexture(mat, aiTextureType_OPACITY, Discreet3DS::CHUNK_MAT_OPACMAP);
+		WriteTexture(mat, aiTextureType_SHININESS, Discreet3DS::CHUNK_MAT_MAT_SHINMAP);
+		WriteTexture(mat, aiTextureType_SPECULAR, Discreet3DS::CHUNK_MAT_SPECMAP);
+		WriteTexture(mat, aiTextureType_EMISSIVE, Discreet3DS::CHUNK_MAT_SELFIMAP);
+		WriteTexture(mat, aiTextureType_REFLECTION, Discreet3DS::CHUNK_MAT_REFLMAP);
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteTexture(const aiMaterial& mat, aiTextureType type, uint16_t chunk_flags) 
+{
+	aiString path;
+	aiTextureMapMode map_mode = aiTextureMapMode_Wrap;
+	float blend = 1.0f;
+	if (mat.GetTexture(type, 0, &path, NULL, NULL, &blend, NULL, &map_mode) != AI_SUCCESS || !path.length) {
+		return;
+	}
+
+	// TODO: handle embedded textures properly
+	if (path.data[0] == '*') {
+		DefaultLogger::get()->error("Ignoring embedded texture for export: " + std::string(path.C_Str()));
+		return;
+	}
+
+	ChunkWriter(writer, chunk_flags);
+	{
+		ChunkWriter(writer, Discreet3DS::CHUNK_MAPFILE);
+		WriteString(path);
+	}
+
+	WritePercentChunk(blend);
+
+	{
+		ChunkWriter(writer, Discreet3DS::CHUNK_MAT_MAP_TILING);
+		uint16_t val = 0; // WRAP
+		if (map_mode == aiTextureMapMode_Mirror) {
+			val = 0x2;
+		}
+		else if (map_mode == aiTextureMapMode_Decal) {
+			val = 0x10;
+		}
+		writer.PutU2(val);
+	}
+	// TODO: export texture transformation (i.e. UV offset, scale, rotation)
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteMeshes()
+{
+	// NOTE: 3DS allows for instances. However:
+	//   i)  not all importers support reading them
+	//   ii) instances are not as flexible as they are in assimp, in particular,
+	//        nodes can carry (and instance) only one mesh.
+	//
+	// This exporter currently deep clones all instanced meshes, i.e. for each mesh
+	// attached to a node a full TRIMESH chunk is written to the file.
+	//
+	// Furthermore, the TRIMESH is transformed into world space so that it will
+	// appear correctly if importers don't read the scene hierarchy at all.
+	for (MeshesByNodeMap::const_iterator it = meshes.begin(); it != meshes.end(); ++it) {
+		const aiNode& node = *(*it).first;
+		const unsigned int mesh_idx = (*it).second;
+
+		const aiMesh& mesh = *scene->mMeshes[mesh_idx];
+
+		// This should not happen if the SLM step is correctly executed
+		// before the scene is handed to the exporter
+		ai_assert(mesh.mNumVertices <= 0xffff);
+		ai_assert(mesh.mNumFaces <= 0xffff);
+
+		const aiMatrix4x4& trafo = trafos[&node];
+
+		ChunkWriter chunk(writer, Discreet3DS::CHUNK_OBJBLOCK);
+
+		// Mesh name is tied to the node it is attached to so it can later be referenced
+		const std::string& name = GetMeshName(mesh, mesh_idx, node);
+		WriteString(name);
+
+
+		// TRIMESH chunk
+		ChunkWriter chunk2(writer, Discreet3DS::CHUNK_TRIMESH);
+
+		// Vertices in world space
+		{
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_VERTLIST);
+
+			const uint16_t count = static_cast<uint16_t>(mesh.mNumVertices);
+			writer.PutU2(count);
+			for (unsigned int i = 0; i < mesh.mNumVertices; ++i) {
+				const aiVector3D& v = trafo * mesh.mVertices[i];
+				writer.PutF4(v.x);
+				writer.PutF4(v.y);
+				writer.PutF4(v.z);
+			}
+		}
+
+		// UV coordinates
+		if (mesh.HasTextureCoords(0)) {
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_MAPLIST);
+			const uint16_t count = static_cast<uint16_t>(mesh.mNumVertices);
+			writer.PutU2(count);
+
+			for (unsigned int i = 0; i < mesh.mNumVertices; ++i) {
+				const aiVector3D& v = mesh.mTextureCoords[0][i];
+				writer.PutF4(v.x);
+				writer.PutF4(v.y);
+			}
+		}
+
+		// Faces (indices)
+		{
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_FACELIST);
+
+			ai_assert(mesh.mNumFaces <= 0xffff);
+
+			// Count triangles, discard lines and points
+			uint16_t count = 0;
+			for (unsigned int i = 0; i < mesh.mNumFaces; ++i) {
+				const aiFace& f = mesh.mFaces[i];
+				if (f.mNumIndices < 3) {
+					continue;
+				}
+				// TRIANGULATE step is a pre-requisite so we should not see polys here
+				ai_assert(f.mNumIndices == 3);
+				++count;
+			}
+
+			writer.PutU2(count);
+			for (unsigned int i = 0; i < mesh.mNumFaces; ++i) {
+				const aiFace& f = mesh.mFaces[i];
+				if (f.mNumIndices < 3) {
+					continue;
+				}
+
+				for (unsigned int j = 0; j < 3; ++j) {
+					ai_assert(f.mIndices[j] <= 0xffff);
+					writer.PutI2(static_cast<uint16_t>(f.mIndices[j]));
+				}
+
+				// Edge visibility flag
+				writer.PutI2(0x0);
+			}
+
+			// TODO: write smoothing groups (CHUNK_SMOOLIST)
+
+			WriteFaceMaterialChunk(mesh);
+		}
+
+		// Transformation matrix by which the mesh vertices have been pre-transformed with.
+		{
+			ChunkWriter chunk(writer, Discreet3DS::CHUNK_TRMATRIX);
+			for (unsigned int r = 0; r < 4; ++r) {
+				for (unsigned int c = 0; c < 3; ++c) {
+					writer.PutF4(trafo[r][c]);
+				}
+			}
+		}
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteFaceMaterialChunk(const aiMesh& mesh)
+{
+	ChunkWriter chunk(writer, Discreet3DS::CHUNK_FACEMAT);
+	const std::string& name = GetMaterialName(*scene->mMaterials[mesh.mMaterialIndex], mesh.mMaterialIndex);
+	WriteString(name);
+
+	// Because assimp splits meshes by material, only a single
+	// FACEMAT chunk needs to be written
+	ai_assert(mesh.mNumFaces <= 0xffff);
+	const uint16_t count = static_cast<uint16_t>(mesh.mNumFaces);
+	writer.PutU2(count);
+
+	for (unsigned int i = 0; i < mesh.mNumFaces; ++i) {
+		writer.PutU2(static_cast<uint16_t>(i));
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteString(const std::string& s) {
+	for (std::string::const_iterator it = s.begin(); it != s.end(); ++it) {
+		writer.PutI1(*it);
+	}
+	writer.PutI1('\0');
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteString(const aiString& s) {
+	for (std::size_t i = 0; i < s.length; ++i) {
+		writer.PutI1(s.data[i]);
+	}
+	writer.PutI1('\0');
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WriteColor(const aiColor3D& color) {
+	ChunkWriter chunk(writer, Discreet3DS::CHUNK_RGBF);
+	writer.PutF4(color.r);
+	writer.PutF4(color.g);
+	writer.PutF4(color.b);
+}
+
+// ------------------------------------------------------------------------------------------------
+void Discreet3DSExporter::WritePercentChunk(float f) {
+	ChunkWriter chunk(writer, Discreet3DS::CHUNK_PERCENTF);
+	writer.PutF4(f);
+}
+
+
+#endif // ASSIMP_BUILD_NO_3DS_EXPORTER
+#endif // ASSIMP_BUILD_NO_EXPORT

code/3DSExporter.h

@@ -0,0 +1,92 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2012, 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 3DSExporter.h
+ * 3DS Exporter Main Header
+ */
+#ifndef AI_3DSEXPORTER_H_INC
+#define AI_3DSEXPORTER_H_INC
+
+#include <map>
+
+#include "StreamWriter.h"
+
+struct aiScene;
+struct aiNode;
+
+namespace Assimp	
+{
+
+// ------------------------------------------------------------------------------------------------
+/** Helper class to export a given scene to a 3DS file. */
+// ------------------------------------------------------------------------------------------------
+class Discreet3DSExporter
+{
+public:
+	Discreet3DSExporter(boost::shared_ptr<IOStream> outfile, const aiScene* pScene);
+
+private:
+
+	void WriteMeshes();
+	void WriteMaterials();
+	void WriteTexture(const aiMaterial& mat, aiTextureType type, uint16_t chunk_flags);
+
+	void WriteFaceMaterialChunk(const aiMesh& mesh);
+
+	void WriteString(const std::string& s);
+	void WriteString(const aiString& s);
+	void WriteColor(const aiColor3D& color);
+	void WritePercentChunk(float f);
+
+private:
+
+	const aiScene* const scene;
+	StreamWriterLE writer;
+
+	std::map<const aiNode*, aiMatrix4x4> trafos;
+
+	typedef std::multimap<const aiNode*, unsigned int> MeshesByNodeMap;
+	MeshesByNodeMap meshes;
+
+};
+
+}
+
+#endif

code/CMakeLists.txt

@@ -111,6 +111,7 @@ SET( Common_SRCS
 	MemoryIOWrapper.h
 	ParsingUtils.h
 	StreamReader.h
+	StreamWriter.h
 	StringComparison.h
 	SGSpatialSort.cpp
 	SGSpatialSort.h
@@ -151,6 +152,8 @@ SET( 3DS_SRCS
 	3DSHelper.h
 	3DSLoader.cpp
 	3DSLoader.h
+	3DSExporter.h
+	3DSExporter.cpp
 )
 SOURCE_GROUP(3DS FILES ${3DS_SRCS})
 

code/Exporter.cpp

@@ -78,7 +78,7 @@ void ExportSceneObj(const char*,IOSystem*, const aiScene*);
 void ExportSceneSTL(const char*,IOSystem*, const aiScene*);
 void ExportSceneSTLBinary(const char*,IOSystem*, const aiScene*);
 void ExportScenePly(const char*,IOSystem*, const aiScene*);
-void ExportScene3DS(const char*, IOSystem*, const aiScene*) {}
+void ExportScene3DS(const char*, IOSystem*, const aiScene*);
 
 // ------------------------------------------------------------------------------------------------
 // global array of all export formats which Assimp supports in its current build
@@ -90,7 +90,7 @@ Exporter::ExportFormatEntry gExporters[] =
 
 #ifndef ASSIMP_BUILD_NO_FXILE_EXPORTER
 	Exporter::ExportFormatEntry( "x", "X Files", "x", &ExportSceneXFile,
-	aiProcess_MakeLeftHanded | aiProcess_FlipWindingOrder | aiProcess_FlipUVs),
+		aiProcess_MakeLeftHanded | aiProcess_FlipWindingOrder | aiProcess_FlipUVs),
 #endif
 
 #ifndef ASSIMP_BUILD_NO_OBJ_EXPORTER
@@ -113,9 +113,10 @@ Exporter::ExportFormatEntry gExporters[] =
 	),
 #endif
 
-//#ifndef ASSIMP_BUILD_NO_3DS_EXPORTER
-//	ExportFormatEntry( "3ds", "Autodesk 3DS (legacy format)", "3ds" , &ExportScene3DS),
-//#endif
+#ifndef ASSIMP_BUILD_NO_3DS_EXPORTER
+	Exporter::ExportFormatEntry( "3ds", "Autodesk 3DS (legacy)", "3ds" , &ExportScene3DS,
+		aiProcess_Triangulate | aiProcess_SortByPType | aiProcess_JoinIdenticalVertices),
+#endif
 };
 
 #define ASSIMP_NUM_EXPORTERS (sizeof(gExporters)/sizeof(gExporters[0]))

code/StreamWriter.h

@@ -80,6 +80,7 @@ public:
 	StreamWriter(boost::shared_ptr<IOStream> stream, bool le = false)
 		: stream(stream)
 		, le(le)
+		, cursor()
 	{
 		ai_assert(stream); 
 		buffer.reserve(INITIAL_CAPACITY);
@@ -89,6 +90,7 @@ public:
 	StreamWriter(IOStream* stream, bool le = false)
 		: stream(boost::shared_ptr<IOStream>(stream))
 		, le(le)
+		, cursor()
 	{
 		ai_assert(stream);
 		buffer.reserve(INITIAL_CAPACITY);