assimp/code/XFileImporter.cpp

/*
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Open Asset Import Library (ASSIMP)
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Copyright (c) 2006-2010, ASSIMP Development Team

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*/
/** @file  XFileImporter.cpp
 *  @brief Implementation of the XFile importer class 
 */

#include "AssimpPCH.h"
#ifndef ASSIMP_BUILD_NO_X_IMPORTER

#include "XFileImporter.h"
#include "XFileParser.h"
#include "ConvertToLHProcess.h"

using namespace Assimp;

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
XFileImporter::XFileImporter()
{}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
XFileImporter::~XFileImporter()
{}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool XFileImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const
{
	std::string extension = GetExtension(pFile);
	if(extension == "x") {
		return true;
	}
	if (!extension.length() || checkSig) {
		uint32_t token[1];
		token[0] = AI_MAKE_MAGIC("xof ");
		return CheckMagicToken(pIOHandler,pFile,token,1,0);
	}
	return false;
}

// ------------------------------------------------------------------------------------------------
void XFileImporter::GetExtensionList(std::set<std::string>& extensions)
{
	extensions.insert("x");
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void XFileImporter::InternReadFile( const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler)
{
	// read file into memory
	boost::scoped_ptr<IOStream> file( pIOHandler->Open( pFile));
	if( file.get() == NULL)
		throw DeadlyImportError( "Failed to open file " + pFile + ".");

	size_t fileSize = file->FileSize();
	if( fileSize < 16)
		throw DeadlyImportError( "XFile is too small.");

	// need to clear members - this method might be called multiple
	// times on a single XFileImporter instance.
	mImportedMats.clear();

	// in the hope that binary files will never start with a BOM ...
	mBuffer.resize( fileSize + 1);
	file->Read( &mBuffer.front(), 1, fileSize);
	ConvertToUTF8(mBuffer);

	// parse the file into a temporary representation
	XFileParser parser( mBuffer);

	// and create the proper return structures out of it
	CreateDataRepresentationFromImport( pScene, parser.GetImportedData());

	// if nothing came from it, report it as error
	if( !pScene->mRootNode)
		throw DeadlyImportError( "XFile is ill-formatted - no content imported.");
}

// ------------------------------------------------------------------------------------------------
// Constructs the return data structure out of the imported data.
void XFileImporter::CreateDataRepresentationFromImport( aiScene* pScene, const XFile::Scene* pData)
{
	// Read the global materials first so that meshes referring to them can find them later
	ConvertMaterials( pScene, pData->mGlobalMaterials);

	// copy nodes, extracting meshes and materials on the way
	pScene->mRootNode = CreateNodes( pScene, NULL, pData->mRootNode);

	// extract animations
	CreateAnimations( pScene, pData);

	// read the global meshes that were stored outside of any node
	if( pData->mGlobalMeshes.size() > 0)
	{
		// create a root node to hold them if there isn't any, yet
		if( pScene->mRootNode == NULL)
		{
			pScene->mRootNode = new aiNode;
			pScene->mRootNode->mName.Set( "$dummy_node");
		}

		// convert all global meshes and store them in the root node.
		// If there was one before, the global meshes now suddenly have its transformation matrix...
		// Don't know what to do there, I don't want to insert another node under the present root node
		// just to avoid this.
		CreateMeshes( pScene, pScene->mRootNode, pData->mGlobalMeshes);
	}

	// Convert everything to OpenGL space... it's the same operation as the conversion back, so we can reuse the step directly
	MakeLeftHandedProcess convertProcess;
	convertProcess.Execute( pScene);

	FlipWindingOrderProcess flipper;
	flipper.Execute(pScene);

	// finally: create a dummy material if not material was imported
	if( pScene->mNumMaterials == 0)
	{
		pScene->mNumMaterials = 1;
		// create the Material
		aiMaterial* mat = new aiMaterial;
		int shadeMode = (int) aiShadingMode_Gouraud;
		mat->AddProperty<int>( &shadeMode, 1, AI_MATKEY_SHADING_MODEL);
		// material colours
		int specExp = 1;

		aiColor3D clr = aiColor3D( 0, 0, 0);
		mat->AddProperty( &clr, 1, AI_MATKEY_COLOR_EMISSIVE);
		mat->AddProperty( &clr, 1, AI_MATKEY_COLOR_SPECULAR);

		clr = aiColor3D( 0.5f, 0.5f, 0.5f);
		mat->AddProperty( &clr, 1, AI_MATKEY_COLOR_DIFFUSE);
		mat->AddProperty( &specExp, 1, AI_MATKEY_SHININESS);

		pScene->mMaterials = new aiMaterial*[1];
		pScene->mMaterials[0] = mat;
	}
}

// ------------------------------------------------------------------------------------------------
// Recursively creates scene nodes from the imported hierarchy. 
aiNode* XFileImporter::CreateNodes( aiScene* pScene, aiNode* pParent, const XFile::Node* pNode)
{
	if( !pNode)
		return NULL;

	// create node
	aiNode* node = new aiNode;
	node->mName.length = pNode->mName.length();
	node->mParent = pParent;
	memcpy( node->mName.data, pNode->mName.c_str(), pNode->mName.length());
	node->mName.data[node->mName.length] = 0;
	node->mTransformation = pNode->mTrafoMatrix;

	// convert meshes from the source node 
	CreateMeshes( pScene, node, pNode->mMeshes);

	// handle childs
	if( pNode->mChildren.size() > 0)
	{
		node->mNumChildren = (unsigned int)pNode->mChildren.size();
		node->mChildren = new aiNode* [node->mNumChildren];

		for( unsigned int a = 0; a < pNode->mChildren.size(); a++)
			node->mChildren[a] = CreateNodes( pScene, node, pNode->mChildren[a]);
	}

	return node;
}

// ------------------------------------------------------------------------------------------------
// Creates the meshes for the given node. 
void XFileImporter::CreateMeshes( aiScene* pScene, aiNode* pNode, const std::vector<XFile::Mesh*>& pMeshes)
{
	if( pMeshes.size() == 0)
		return;

	// create a mesh for each mesh-material combination in the source node
	std::vector<aiMesh*> meshes;
	for( unsigned int a = 0; a < pMeshes.size(); a++)
	{
		const XFile::Mesh* sourceMesh = pMeshes[a];
		// first convert its materials so that we can find them when searching by name afterwards
		ConvertMaterials( pScene, sourceMesh->mMaterials);

		unsigned int numMaterials = std::max( (unsigned int)sourceMesh->mMaterials.size(), 1u);
		for( unsigned int b = 0; b < numMaterials; b++)
		{
			// collect the faces belonging to this material
			std::vector<unsigned int> faces;
			unsigned int numVertices = 0;
			if( sourceMesh->mFaceMaterials.size() > 0)
			{
				// if there is a per-face material defined, select the faces with the corresponding material
				for( unsigned int c = 0; c < sourceMesh->mFaceMaterials.size(); c++)
				{
					if( sourceMesh->mFaceMaterials[c] == b)
					{
						faces.push_back( c);
						numVertices += (unsigned int)sourceMesh->mPosFaces[c].mIndices.size();
					}
				}
			} else
			{
				// if there is no per-face material, place everything into one mesh
				for( unsigned int c = 0; c < sourceMesh->mPosFaces.size(); c++)
				{
					faces.push_back( c);
					numVertices += (unsigned int)sourceMesh->mPosFaces[c].mIndices.size();
				}
			}

			// no faces/vertices using this material? strange...
			if( numVertices == 0)
				continue;

			// create a submesh using this material
			aiMesh* mesh = new aiMesh;
			meshes.push_back( mesh);

			// find the material by name in the scene's material list. Either own material
			// or referenced material, it should already be found there
			if( sourceMesh->mFaceMaterials.size() > 0)
			{
				std::map<std::string, unsigned int>::const_iterator matIt = mImportedMats.find( sourceMesh->mMaterials[b].mName);
				if( matIt == mImportedMats.end())
					mesh->mMaterialIndex = 0;
				else
					mesh->mMaterialIndex = matIt->second;
			} else
			{
				mesh->mMaterialIndex = 0;
			}

			// Create properly sized data arrays in the mesh. We store unique vertices per face,
			// as specified 
			mesh->mNumVertices = numVertices;
			mesh->mVertices = new aiVector3D[numVertices];
			mesh->mNumFaces = (unsigned int)faces.size();
			mesh->mFaces = new aiFace[mesh->mNumFaces];

			// normals?
			if( sourceMesh->mNormals.size() > 0)
				mesh->mNormals = new aiVector3D[numVertices];
			// texture coords
			for( unsigned int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS; c++)
			{
				if( sourceMesh->mTexCoords[c].size() > 0)
					mesh->mTextureCoords[c] = new aiVector3D[numVertices];
			}
			// vertex colors
			for( unsigned int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS; c++)
			{
				if( sourceMesh->mColors[c].size() > 0)
					mesh->mColors[c] = new aiColor4D[numVertices];
			}

			// now collect the vertex data of all data streams present in the imported mesh
			unsigned int newIndex = 0;
			std::vector<unsigned int> orgPoints; // from which original point each new vertex stems
			orgPoints.resize( numVertices, 0);

			for( unsigned int c = 0; c < faces.size(); c++)
			{
				unsigned int f = faces[c]; // index of the source face
				const XFile::Face& pf = sourceMesh->mPosFaces[f]; // position source face

				// create face. either triangle or triangle fan depending on the index count
				aiFace& df = mesh->mFaces[c]; // destination face
				df.mNumIndices = (unsigned int)pf.mIndices.size();
				df.mIndices = new unsigned int[ df.mNumIndices];

				// collect vertex data for indices of this face
				for( unsigned int d = 0; d < df.mNumIndices; d++)
				{
					df.mIndices[d] = newIndex; 
					orgPoints[newIndex] = pf.mIndices[d];

					// Position
					mesh->mVertices[newIndex] = sourceMesh->mPositions[pf.mIndices[d]];
					// Normal, if present
					if( mesh->HasNormals())
						mesh->mNormals[newIndex] = sourceMesh->mNormals[sourceMesh->mNormFaces[f].mIndices[d]];

					// texture coord sets
					for( unsigned int e = 0; e < AI_MAX_NUMBER_OF_TEXTURECOORDS; e++)
					{
						if( mesh->HasTextureCoords( e))
						{
							aiVector2D tex = sourceMesh->mTexCoords[e][pf.mIndices[d]];
							mesh->mTextureCoords[e][newIndex] = aiVector3D( tex.x, 1.0f - tex.y, 0.0f);
						}
					}
					// vertex color sets
					for( unsigned int e = 0; e < AI_MAX_NUMBER_OF_COLOR_SETS; e++)
						if( mesh->HasVertexColors( e))
							mesh->mColors[e][newIndex] = sourceMesh->mColors[e][pf.mIndices[d]];

					newIndex++;
				}
			}

			// there should be as much new vertices as we calculated before
			assert( newIndex == numVertices);

			// convert all bones of the source mesh which influence vertices in this newly created mesh
			const std::vector<XFile::Bone>& bones = sourceMesh->mBones;
			std::vector<aiBone*> newBones;
			for( unsigned int c = 0; c < bones.size(); c++)
			{
				const XFile::Bone& obone = bones[c];
				// set up a vertex-linear array of the weights for quick searching if a bone influences a vertex
				std::vector<float> oldWeights( sourceMesh->mPositions.size(), 0.0f);
				for( unsigned int d = 0; d < obone.mWeights.size(); d++)
					oldWeights[obone.mWeights[d].mVertex] = obone.mWeights[d].mWeight;

				// collect all vertex weights that influence a vertex in the new mesh
				std::vector<aiVertexWeight> newWeights;
				newWeights.reserve( numVertices);
				for( unsigned int d = 0; d < orgPoints.size(); d++)
				{
					// does the new vertex stem from an old vertex which was influenced by this bone?
					float w = oldWeights[orgPoints[d]];
					if( w > 0.0f)
						newWeights.push_back( aiVertexWeight( d, w));
				}

				// if the bone has no weights in the newly created mesh, ignore it
				if( newWeights.size() == 0)
					continue;

				// create
				aiBone* nbone = new aiBone;
				newBones.push_back( nbone);
				// copy name and matrix
				nbone->mName.Set( obone.mName);
				nbone->mOffsetMatrix = obone.mOffsetMatrix;
				nbone->mNumWeights = (unsigned int)newWeights.size();
				nbone->mWeights = new aiVertexWeight[nbone->mNumWeights];
				for( unsigned int d = 0; d < newWeights.size(); d++)
					nbone->mWeights[d] = newWeights[d];
			}

			// store the bones in the mesh
			mesh->mNumBones = (unsigned int)newBones.size();
			if( newBones.size() > 0)
			{
				mesh->mBones = new aiBone*[mesh->mNumBones];
				std::copy( newBones.begin(), newBones.end(), mesh->mBones);
			}
		}
	}

	// reallocate scene mesh array to be large enough
	aiMesh** prevArray = pScene->mMeshes;
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes + meshes.size()];
	if( prevArray)
	{
		memcpy( pScene->mMeshes, prevArray, pScene->mNumMeshes * sizeof( aiMesh*));
		delete [] prevArray;
	}

	// allocate mesh index array in the node
	pNode->mNumMeshes = (unsigned int)meshes.size();
	pNode->mMeshes = new unsigned int[pNode->mNumMeshes];

	// store all meshes in the mesh library of the scene and store their indices in the node
	for( unsigned int a = 0; a < meshes.size(); a++)
	{
		pScene->mMeshes[pScene->mNumMeshes] = meshes[a];		
		pNode->mMeshes[a] = pScene->mNumMeshes;
		pScene->mNumMeshes++;
	}
}

// ------------------------------------------------------------------------------------------------
// Converts the animations from the given imported data and creates them in the scene.
void XFileImporter::CreateAnimations( aiScene* pScene, const XFile::Scene* pData)
{
	std::vector<aiAnimation*> newAnims;

	for( unsigned int a = 0; a < pData->mAnims.size(); a++)
	{
		const XFile::Animation* anim = pData->mAnims[a];
		// some exporters mock me with empty animation tags.
		if( anim->mAnims.size() == 0)
			continue;

		// create a new animation to hold the data
		aiAnimation* nanim = new aiAnimation;
		newAnims.push_back( nanim);
		nanim->mName.Set( anim->mName);
		// duration will be determined by the maximum length
		nanim->mDuration = 0;
		nanim->mTicksPerSecond = pData->mAnimTicksPerSecond;
		nanim->mNumChannels = (unsigned int)anim->mAnims.size();
		nanim->mChannels = new aiNodeAnim*[nanim->mNumChannels];

		for( unsigned int b = 0; b < anim->mAnims.size(); b++)
		{
			const XFile::AnimBone* bone = anim->mAnims[b];
			aiNodeAnim* nbone = new aiNodeAnim;
			nbone->mNodeName.Set( bone->mBoneName);
			nanim->mChannels[b] = nbone;

			// keyframes are given as combined transformation matrix keys
			if( bone->mTrafoKeys.size() > 0)
			{
				nbone->mNumPositionKeys = (unsigned int)bone->mTrafoKeys.size();
				nbone->mPositionKeys = new aiVectorKey[nbone->mNumPositionKeys];
				nbone->mNumRotationKeys = (unsigned int)bone->mTrafoKeys.size();
				nbone->mRotationKeys = new aiQuatKey[nbone->mNumRotationKeys];
				nbone->mNumScalingKeys = (unsigned int)bone->mTrafoKeys.size();
				nbone->mScalingKeys = new aiVectorKey[nbone->mNumScalingKeys];

				for( unsigned int c = 0; c < bone->mTrafoKeys.size(); c++)
				{
					// deconstruct each matrix into separate position, rotation and scaling
					double time = bone->mTrafoKeys[c].mTime;
					aiMatrix4x4 trafo = bone->mTrafoKeys[c].mMatrix;

					// extract position
					aiVector3D pos( trafo.a4, trafo.b4, trafo.c4);

					nbone->mPositionKeys[c].mTime = time;
					nbone->mPositionKeys[c].mValue = pos;

					// extract scaling
					aiVector3D scale;
					scale.x = aiVector3D( trafo.a1, trafo.b1, trafo.c1).Length();
					scale.y = aiVector3D( trafo.a2, trafo.b2, trafo.c2).Length();
					scale.z = aiVector3D( trafo.a3, trafo.b3, trafo.c3).Length();
					nbone->mScalingKeys[c].mTime = time;
					nbone->mScalingKeys[c].mValue = scale;

					// reconstruct rotation matrix without scaling
					aiMatrix3x3 rotmat( 
						trafo.a1 / scale.x, trafo.a2 / scale.y, trafo.a3 / scale.z,
						trafo.b1 / scale.x, trafo.b2 / scale.y, trafo.b3 / scale.z,
						trafo.c1 / scale.x, trafo.c2 / scale.y, trafo.c3 / scale.z);

					// and convert it into a quaternion
					nbone->mRotationKeys[c].mTime = time;
					nbone->mRotationKeys[c].mValue = aiQuaternion( rotmat);
				}

				// longest lasting key sequence determines duration
				nanim->mDuration = std::max( nanim->mDuration, bone->mTrafoKeys.back().mTime);
			} else
			{
				// separate key sequences for position, rotation, scaling
				nbone->mNumPositionKeys = (unsigned int)bone->mPosKeys.size(); 
				nbone->mPositionKeys = new aiVectorKey[nbone->mNumPositionKeys];
				for( unsigned int c = 0; c < nbone->mNumPositionKeys; c++)
				{
					aiVector3D pos = bone->mPosKeys[c].mValue;

					nbone->mPositionKeys[c].mTime = bone->mPosKeys[c].mTime;
					nbone->mPositionKeys[c].mValue = pos;
				}

				// rotation
				nbone->mNumRotationKeys = (unsigned int)bone->mRotKeys.size(); 
				nbone->mRotationKeys = new aiQuatKey[nbone->mNumRotationKeys];
				for( unsigned int c = 0; c < nbone->mNumRotationKeys; c++)
				{
					aiMatrix3x3 rotmat = bone->mRotKeys[c].mValue.GetMatrix();

					nbone->mRotationKeys[c].mTime = bone->mRotKeys[c].mTime;
					nbone->mRotationKeys[c].mValue = aiQuaternion( rotmat);
					nbone->mRotationKeys[c].mValue.w *= -1.0f; // needs quat inversion
				}

				// scaling
				nbone->mNumScalingKeys = (unsigned int)bone->mScaleKeys.size(); 
				nbone->mScalingKeys = new aiVectorKey[nbone->mNumScalingKeys];
				for( unsigned int c = 0; c < nbone->mNumScalingKeys; c++)
					nbone->mScalingKeys[c] = bone->mScaleKeys[c];

				// longest lasting key sequence determines duration
				if( bone->mPosKeys.size() > 0)
					nanim->mDuration = std::max( nanim->mDuration, bone->mPosKeys.back().mTime);
				if( bone->mRotKeys.size() > 0)
					nanim->mDuration = std::max( nanim->mDuration, bone->mRotKeys.back().mTime);
				if( bone->mScaleKeys.size() > 0)
					nanim->mDuration = std::max( nanim->mDuration, bone->mScaleKeys.back().mTime);
			}
		}
	}

	// store all converted animations in the scene
	if( newAnims.size() > 0)
	{
		pScene->mNumAnimations = (unsigned int)newAnims.size();
		pScene->mAnimations = new aiAnimation* [pScene->mNumAnimations];
		for( unsigned int a = 0; a < newAnims.size(); a++)
			pScene->mAnimations[a] = newAnims[a];
	}
}

// ------------------------------------------------------------------------------------------------
// Converts all materials in the given array and stores them in the scene's material list.
void XFileImporter::ConvertMaterials( aiScene* pScene, const std::vector<XFile::Material>& pMaterials)
{
	// count the non-referrer materials in the array
	unsigned int numMaterials = 0;
	for( unsigned int a = 0; a < pMaterials.size(); a++)
		if( !pMaterials[a].mIsReference)
			numMaterials++;

	if( numMaterials == 0)
		return;

	// resize the scene's material list to offer enough space for the new materials
	aiMaterial** prevMats = pScene->mMaterials;
	pScene->mMaterials = new aiMaterial*[pScene->mNumMaterials + numMaterials];
	if( prevMats)
	{
		memcpy( pScene->mMaterials, prevMats, pScene->mNumMaterials * sizeof( aiMaterial*));
		delete [] prevMats;
	}

	// convert all the materials given in the array
	for( unsigned int a = 0; a < pMaterials.size(); a++)
	{
		const XFile::Material& oldMat = pMaterials[a];
		if( oldMat.mIsReference)
			continue;

		aiMaterial* mat = new aiMaterial;
		aiString name;
		name.Set( oldMat.mName);
		mat->AddProperty( &name, AI_MATKEY_NAME);

		// Shading model: hardcoded to PHONG, there is no such information in an XFile
		// FIX (aramis): If the specular exponent is 0, use gouraud shading. This is a bugfix
		// for some models in the SDK (e.g. good old tiny.x)
		int shadeMode = (int)oldMat.mSpecularExponent == 0.0f 
			? aiShadingMode_Gouraud : aiShadingMode_Phong;

		mat->AddProperty<int>( &shadeMode, 1, AI_MATKEY_SHADING_MODEL);
		// material colours
		// FIX: Setup this as ambient not as emissive color
		mat->AddProperty( &oldMat.mEmissive, 1, AI_MATKEY_COLOR_AMBIENT);
		mat->AddProperty( &oldMat.mDiffuse, 1, AI_MATKEY_COLOR_DIFFUSE);
		mat->AddProperty( &oldMat.mSpecular, 1, AI_MATKEY_COLOR_SPECULAR);
		mat->AddProperty( &oldMat.mSpecularExponent, 1, AI_MATKEY_SHININESS);


		// texture, if there is one
		if (1 == oldMat.mTextures.size())
		{
			const XFile::TexEntry& otex = oldMat.mTextures.back();
			if (otex.mName.length())
			{
				// if there is only one texture assume it contains the diffuse color
				aiString tex( otex.mName);
				if( otex.mIsNormalMap)
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_NORMALS(0));
				else
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_DIFFUSE(0));
			}
		}
		else
		{
			// Otherwise ... try to search for typical strings in the
			// texture's file name like 'bump' or 'diffuse'
			unsigned int iHM = 0,iNM = 0,iDM = 0,iSM = 0,iAM = 0,iEM = 0;
			for( unsigned int b = 0; b < oldMat.mTextures.size(); b++)
			{
				const XFile::TexEntry& otex = oldMat.mTextures[b];
				std::string sz = otex.mName;
				if (!sz.length())continue;


				// find the file name
				//const size_t iLen = sz.length();
				std::string::size_type s = sz.find_last_of("\\/");
				if (std::string::npos == s)
					s = 0;

				// cut off the file extension
				std::string::size_type sExt = sz.find_last_of('.');
				if (std::string::npos != sExt){
					sz[sExt] = '\0';
				}

				// convert to lower case for easier comparision
				for( unsigned int c = 0; c < sz.length(); c++)
					if( isalpha( sz[c]))
						sz[c] = tolower( sz[c]);


				// Place texture filename property under the corresponding name
				aiString tex( oldMat.mTextures[b].mName);

				// bump map
				if (std::string::npos != sz.find("bump", s) || std::string::npos != sz.find("height", s))
				{
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_HEIGHT(iHM++));
				} else
				if (otex.mIsNormalMap || std::string::npos != sz.find( "normal", s) || std::string::npos != sz.find("nm", s))
				{
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_NORMALS(iNM++));
				} else
				if (std::string::npos != sz.find( "spec", s) || std::string::npos != sz.find( "glanz", s))
				{
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_SPECULAR(iSM++));
				} else
				if (std::string::npos != sz.find( "ambi", s) || std::string::npos != sz.find( "env", s))
				{
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_AMBIENT(iAM++));
				} else
				if (std::string::npos != sz.find( "emissive", s) || std::string::npos != sz.find( "self", s))
				{
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_EMISSIVE(iEM++));
				} else
				{
					// Assume it is a diffuse texture
					mat->AddProperty( &tex, AI_MATKEY_TEXTURE_DIFFUSE(iDM++));
				}
			}
		}

		pScene->mMaterials[pScene->mNumMaterials] = mat;
		mImportedMats[oldMat.mName] = pScene->mNumMaterials;
		pScene->mNumMaterials++;
	}
}

#endif // !! ASSIMP_BUILD_NO_X_IMPORTER