assimp/code/MD3Loader.cpp

/*
---------------------------------------------------------------------------
Open Asset Import Library (assimp)
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  following disclaimer.

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*/

/** @file MD3Loader.cpp
 *  @brief Implementation of the MD3 importer class 
 * 
 *  Sources: 
 *     http://www.gamers.org/dEngine/quake3/UQ3S
 *     http://linux.ucla.edu/~phaethon/q3/formats/md3format.html
 *     http://www.heppler.com/shader/shader/
 */


#ifndef ASSIMP_BUILD_NO_MD3_IMPORTER

#include "MD3Loader.h"
#include "SceneCombiner.h"
#include "GenericProperty.h"
#include "RemoveComments.h"
#include "ParsingUtils.h"
#include "Importer.h"
#include "../include/assimp/DefaultLogger.hpp"
#include <boost/scoped_ptr.hpp>
#include "../include/assimp/IOSystem.hpp"
#include "../include/assimp/material.h"
#include "../include/assimp/scene.h"
#include <cctype>



using namespace Assimp;

static const aiImporterDesc desc = {
	"Quake III Mesh Importer",
	"",
	"",
	"",
	aiImporterFlags_SupportBinaryFlavour,
	0,
	0,
	0,
	0,
	"md3" 
};

// ------------------------------------------------------------------------------------------------
// Convert a Q3 shader blend function to the appropriate enum value
Q3Shader::BlendFunc StringToBlendFunc(const std::string& m)
{
	if (m == "GL_ONE") {
		return Q3Shader::BLEND_GL_ONE;
	}
	if (m == "GL_ZERO") {
		return Q3Shader::BLEND_GL_ZERO;
	}
	if (m == "GL_SRC_ALPHA") {
		return Q3Shader::BLEND_GL_SRC_ALPHA;
	}
	if (m == "GL_ONE_MINUS_SRC_ALPHA") {
		return Q3Shader::BLEND_GL_ONE_MINUS_SRC_ALPHA;
	}
	if (m == "GL_ONE_MINUS_DST_COLOR") {
		return Q3Shader::BLEND_GL_ONE_MINUS_DST_COLOR;
	}
	DefaultLogger::get()->error("Q3Shader: Unknown blend function: " + m);
	return Q3Shader::BLEND_NONE;
}

// ------------------------------------------------------------------------------------------------
// Load a Quake 3 shader
bool Q3Shader::LoadShader(ShaderData& fill, const std::string& pFile,IOSystem* io)
{
	boost::scoped_ptr<IOStream> file( io->Open( pFile, "rt"));
	if (!file.get())
		return false; // if we can't access the file, don't worry and return

	DefaultLogger::get()->info("Loading Quake3 shader file " + pFile);

	// read file in memory
	const size_t s = file->FileSize();
	std::vector<char> _buff(s+1);
	file->Read(&_buff[0],s,1);
	_buff[s] = 0;

	// remove comments from it (C++ style)
	CommentRemover::RemoveLineComments("//",&_buff[0]);
	const char* buff = &_buff[0];

	Q3Shader::ShaderDataBlock* curData = NULL;
	Q3Shader::ShaderMapBlock*  curMap  = NULL;

	// read line per line
	for (;SkipSpacesAndLineEnd(&buff);SkipLine(&buff)) {
	
		if (*buff == '{') {
			++buff;

			// append to last section, if any
			if (!curData) {
				DefaultLogger::get()->error("Q3Shader: Unexpected shader section token \'{\'");
				return true; // still no failure, the file is there
			}

			// read this data section
			for (;SkipSpacesAndLineEnd(&buff);SkipLine(&buff)) {
				if (*buff == '{') {
					++buff;
					// add new map section
					curData->maps.push_back(Q3Shader::ShaderMapBlock());
					curMap = &curData->maps.back();

					for (;SkipSpacesAndLineEnd(&buff);SkipLine(&buff)) {
						// 'map' - Specifies texture file name
						if (TokenMatchI(buff,"map",3) || TokenMatchI(buff,"clampmap",8)) {
							curMap->name = GetNextToken(buff);
						}	
						// 'blendfunc' - Alpha blending mode
						else if (TokenMatchI(buff,"blendfunc",9)) {	
							const std::string blend_src = GetNextToken(buff);
							if (blend_src == "add") {
								curMap->blend_src  = Q3Shader::BLEND_GL_ONE;
								curMap->blend_dest = Q3Shader::BLEND_GL_ONE;
							}
							else if (blend_src == "filter") {
								curMap->blend_src  = Q3Shader::BLEND_GL_DST_COLOR;
								curMap->blend_dest = Q3Shader::BLEND_GL_ZERO;
							}
							else if (blend_src == "blend") {
								curMap->blend_src  = Q3Shader::BLEND_GL_SRC_ALPHA;
								curMap->blend_dest = Q3Shader::BLEND_GL_ONE_MINUS_SRC_ALPHA;
							}
							else {
								curMap->blend_src  = StringToBlendFunc(blend_src);
								curMap->blend_dest = StringToBlendFunc(GetNextToken(buff));
							}
						}
						// 'alphafunc' - Alpha testing mode
						else if (TokenMatchI(buff,"alphafunc",9)) {	
							const std::string at = GetNextToken(buff);
							if (at == "GT0") {
								curMap->alpha_test = Q3Shader::AT_GT0;
							}
							else if (at == "LT128") {
								curMap->alpha_test = Q3Shader::AT_LT128;
							}
							else if (at == "GE128") {
								curMap->alpha_test = Q3Shader::AT_GE128;
							}
						}
						else if (*buff == '}') {
							++buff;
							// close this map section
							curMap = NULL;
							break;
						}
					}

				}
				else if (*buff == '}') {
					++buff;
					curData = NULL;					
					break;
				}

				// 'cull' specifies culling behaviour for the model
				else if (TokenMatchI(buff,"cull",4)) {
					SkipSpaces(&buff);
					if (!ASSIMP_strincmp(buff,"back",4)) {
						curData->cull = Q3Shader::CULL_CCW;
					}
					else if (!ASSIMP_strincmp(buff,"front",5)) {
						curData->cull = Q3Shader::CULL_CW;
					}
					else if (!ASSIMP_strincmp(buff,"none",4) || !ASSIMP_strincmp(buff,"disable",7)) {
						curData->cull = Q3Shader::CULL_NONE;
					}
					else DefaultLogger::get()->error("Q3Shader: Unrecognized cull mode");
				}
			}
		}

		else {
			// add new section
			fill.blocks.push_back(Q3Shader::ShaderDataBlock());
			curData = &fill.blocks.back();

			// get the name of this section
			curData->name = GetNextToken(buff);
		}
	}
	return true;
}

// ------------------------------------------------------------------------------------------------
// Load a Quake 3 skin
bool Q3Shader::LoadSkin(SkinData& fill, const std::string& pFile,IOSystem* io)
{
	boost::scoped_ptr<IOStream> file( io->Open( pFile, "rt"));
	if (!file.get())
		return false; // if we can't access the file, don't worry and return

	DefaultLogger::get()->info("Loading Quake3 skin file " + pFile);

	// read file in memory
	const size_t s = file->FileSize();
	std::vector<char> _buff(s+1);const char* buff = &_buff[0];
	file->Read(&_buff[0],s,1);
	_buff[s] = 0;

	// remove commas
	std::replace(_buff.begin(),_buff.end(),',',' ');

	// read token by token and fill output table
	for (;*buff;) {
		SkipSpacesAndLineEnd(&buff);

		// get first identifier
		std::string ss = GetNextToken(buff);
		
		// ignore tokens starting with tag_
		if (!::strncmp(&ss[0],"tag_",std::min((size_t)4, ss.length())))
			continue;

		fill.textures.push_back(SkinData::TextureEntry());
		SkinData::TextureEntry& s = fill.textures.back();

		s.first  = ss;
		s.second = GetNextToken(buff);
	}
	return true;
}

// ------------------------------------------------------------------------------------------------
// Convert Q3Shader to material
void Q3Shader::ConvertShaderToMaterial(aiMaterial* out, const ShaderDataBlock& shader)
{
	ai_assert(NULL != out);

	/*  IMPORTANT: This is not a real conversion. Actually we're just guessing and
	 *  hacking around to build an aiMaterial that looks nearly equal to the
	 *  original Quake 3 shader. We're missing some important features like
	 *  animatable material properties in our material system, but at least 
	 *  multiple textures should be handled correctly.
	 */ 

	// Two-sided material?
	if (shader.cull == Q3Shader::CULL_NONE) {
		const int twosided = 1;
		out->AddProperty(&twosided,1,AI_MATKEY_TWOSIDED);
	}

	unsigned int cur_emissive = 0, cur_diffuse = 0, cur_lm =0;

	// Iterate through all textures
	for (std::list< Q3Shader::ShaderMapBlock >::const_iterator it = shader.maps.begin(); it != shader.maps.end();++it) {
		
		// CONVERSION BEHAVIOUR:
		//
		//
		// If the texture is additive
		//  - if it is the first texture, assume additive blending for the whole material
		//  - otherwise register it as emissive texture.
		//
		// If the texture is using standard blend (or if the blend mode is unknown)
		//  - if first texture: assume default blending for material
		//  - in any case: set it as diffuse texture
		//
		// If the texture is using 'filter' blending
		//  - take as lightmap
		//
		// Textures with alpha funcs
		//  - aiTextureFlags_UseAlpha is set (otherwise aiTextureFlags_NoAlpha is explicitly set)
		aiString s((*it).name);
		aiTextureType type; unsigned int index;

		if ((*it).blend_src == Q3Shader::BLEND_GL_ONE && (*it).blend_dest == Q3Shader::BLEND_GL_ONE) {
			if (it == shader.maps.begin()) {
				const int additive = aiBlendMode_Additive;
				out->AddProperty(&additive,1,AI_MATKEY_BLEND_FUNC);
				
				index = cur_diffuse++;
				type  = aiTextureType_DIFFUSE;
			}
			else {
				index = cur_emissive++;
				type  = aiTextureType_EMISSIVE;
			}
		}
		else if ((*it).blend_src == Q3Shader::BLEND_GL_DST_COLOR && (*it).blend_dest == Q3Shader::BLEND_GL_ZERO) {
			index = cur_lm++;
			type  = aiTextureType_LIGHTMAP;
		}
		else {
			const int blend = aiBlendMode_Default;
			out->AddProperty(&blend,1,AI_MATKEY_BLEND_FUNC);
			
			index = cur_diffuse++;
			type  = aiTextureType_DIFFUSE;
		}

		// setup texture
		out->AddProperty(&s,AI_MATKEY_TEXTURE(type,index));

		// setup texture flags
		const int use_alpha = ((*it).alpha_test != Q3Shader::AT_NONE ? aiTextureFlags_UseAlpha : aiTextureFlags_IgnoreAlpha);
		out->AddProperty(&use_alpha,1,AI_MATKEY_TEXFLAGS(type,index));
	}
	// If at least one emissive texture was set, set the emissive base color to 1 to ensure
	// the texture is actually displayed.
	if (0 != cur_emissive) {
		aiColor3D one(1.f,1.f,1.f);
		out->AddProperty(&one,1,AI_MATKEY_COLOR_EMISSIVE);
	}
}

// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
MD3Importer::MD3Importer()
: configFrameID  (0)
, configHandleMP (true)
{}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
MD3Importer::~MD3Importer()
{}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool MD3Importer::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const
{
	const std::string extension = GetExtension(pFile);
	if (extension == "md3")
		return true;

	// if check for extension is not enough, check for the magic tokens 
	if (!extension.length() || checkSig) {
		uint32_t tokens[1]; 
		tokens[0] = AI_MD3_MAGIC_NUMBER_LE;
		return CheckMagicToken(pIOHandler,pFile,tokens,1);
	}
	return false;
}

// ------------------------------------------------------------------------------------------------
void MD3Importer::ValidateHeaderOffsets()
{
	// Check magic number
	if (pcHeader->IDENT != AI_MD3_MAGIC_NUMBER_BE &&
		pcHeader->IDENT != AI_MD3_MAGIC_NUMBER_LE)
			throw DeadlyImportError( "Invalid MD3 file: Magic bytes not found");

	// Check file format version
	if (pcHeader->VERSION > 15)
		DefaultLogger::get()->warn( "Unsupported MD3 file version. Continuing happily ...");

	// Check some offset values whether they are valid
	if (!pcHeader->NUM_SURFACES)
		throw DeadlyImportError( "Invalid md3 file: NUM_SURFACES is 0");

	if (pcHeader->OFS_FRAMES >= fileSize || pcHeader->OFS_SURFACES >= fileSize || 
		pcHeader->OFS_EOF > fileSize) {
		throw DeadlyImportError("Invalid MD3 header: some offsets are outside the file");
	}

	if (pcHeader->NUM_FRAMES <= configFrameID )
		throw DeadlyImportError("The requested frame is not existing the file");
}

// ------------------------------------------------------------------------------------------------
void MD3Importer::ValidateSurfaceHeaderOffsets(const MD3::Surface* pcSurf)
{
	// Calculate the relative offset of the surface
	const int32_t ofs = int32_t((const unsigned char*)pcSurf-this->mBuffer);

	// Check whether all data chunks are inside the valid range
	if (pcSurf->OFS_TRIANGLES + ofs + pcSurf->NUM_TRIANGLES * sizeof(MD3::Triangle)	> fileSize  ||
		pcSurf->OFS_SHADERS + ofs + pcSurf->NUM_SHADER * sizeof(MD3::Shader) > fileSize         ||
		pcSurf->OFS_ST + ofs + pcSurf->NUM_VERTICES * sizeof(MD3::TexCoord) > fileSize          ||
		pcSurf->OFS_XYZNORMAL + ofs + pcSurf->NUM_VERTICES * sizeof(MD3::Vertex) > fileSize)	{

		throw DeadlyImportError("Invalid MD3 surface header: some offsets are outside the file");
	}

	// Check whether all requirements for Q3 files are met. We don't
	// care, but probably someone does.
	if (pcSurf->NUM_TRIANGLES > AI_MD3_MAX_TRIANGLES) {
		DefaultLogger::get()->warn("MD3: Quake III triangle limit exceeded");
	}

	if (pcSurf->NUM_SHADER > AI_MD3_MAX_SHADERS) {
		DefaultLogger::get()->warn("MD3: Quake III shader limit exceeded");
	}

	if (pcSurf->NUM_VERTICES > AI_MD3_MAX_VERTS) {
		DefaultLogger::get()->warn("MD3: Quake III vertex limit exceeded");
	}

	if (pcSurf->NUM_FRAMES > AI_MD3_MAX_FRAMES) {
		DefaultLogger::get()->warn("MD3: Quake III frame limit exceeded");
	}
}

// ------------------------------------------------------------------------------------------------
const aiImporterDesc* MD3Importer::GetInfo () const
{
	return &desc;
}

// ------------------------------------------------------------------------------------------------
// Setup configuration properties
void MD3Importer::SetupProperties(const Importer* pImp)
{
	// The 
	// AI_CONFIG_IMPORT_MD3_KEYFRAME option overrides the
	// AI_CONFIG_IMPORT_GLOBAL_KEYFRAME option.
	configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_MD3_KEYFRAME,-1);
	if(static_cast<unsigned int>(-1) == configFrameID) {
		configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_GLOBAL_KEYFRAME,0);
	}

	// AI_CONFIG_IMPORT_MD3_HANDLE_MULTIPART
	configHandleMP = (0 != pImp->GetPropertyInteger(AI_CONFIG_IMPORT_MD3_HANDLE_MULTIPART,1));

	// AI_CONFIG_IMPORT_MD3_SKIN_NAME
	configSkinFile = (pImp->GetPropertyString(AI_CONFIG_IMPORT_MD3_SKIN_NAME,"default"));

	// AI_CONFIG_IMPORT_MD3_SHADER_SRC
	configShaderFile = (pImp->GetPropertyString(AI_CONFIG_IMPORT_MD3_SHADER_SRC,""));

	// AI_CONFIG_FAVOUR_SPEED
	configSpeedFlag = (0 != pImp->GetPropertyInteger(AI_CONFIG_FAVOUR_SPEED,0));
}

// ------------------------------------------------------------------------------------------------
// Try to read the skin for a MD3 file
void MD3Importer::ReadSkin(Q3Shader::SkinData& fill) const
{
	// skip any postfixes (e.g. lower_1.md3)
	std::string::size_type s = filename.find_last_of('_');
	if (s == std::string::npos) {
		s = filename.find_last_of('.');
		if (s == std::string::npos) {
			s = filename.size();
		}
	}
	ai_assert(s != std::string::npos);

	const std::string skin_file = path + filename.substr(0,s) + "_" + configSkinFile + ".skin";
	Q3Shader::LoadSkin(fill,skin_file,mIOHandler);
}

// ------------------------------------------------------------------------------------------------
// Try to read the shader for a MD3 file
void MD3Importer::ReadShader(Q3Shader::ShaderData& fill) const
{
	// Determine Q3 model name from given path
	const std::string::size_type s = path.find_last_of("\\/",path.length()-2);
	const std::string model_file = path.substr(s+1,path.length()-(s+2));

	// If no specific dir or file is given, use our default search behaviour
	if (!configShaderFile.length()) {
		if(!Q3Shader::LoadShader(fill,path + "..\\..\\..\\scripts\\" + model_file + ".shader",mIOHandler)) {
			Q3Shader::LoadShader(fill,path + "..\\..\\..\\scripts\\" + filename + ".shader",mIOHandler);
		}
	}
	else {
		// If the given string specifies a file, load this file.
		// Otherwise it's a directory.
		const std::string::size_type st = configShaderFile.find_last_of('.');
		if (st == std::string::npos) {
			
			if(!Q3Shader::LoadShader(fill,configShaderFile + model_file + ".shader",mIOHandler)) {
				Q3Shader::LoadShader(fill,configShaderFile + filename + ".shader",mIOHandler);
			}
		}
		else {
			Q3Shader::LoadShader(fill,configShaderFile,mIOHandler);
		}
	}
}

// ------------------------------------------------------------------------------------------------
// Tiny helper to remove a single node from its parent' list
void RemoveSingleNodeFromList(aiNode* nd)
{
	if (!nd || nd->mNumChildren || !nd->mParent)return;
	aiNode* par = nd->mParent;
	for (unsigned int i = 0; i < par->mNumChildren;++i) {
		if (par->mChildren[i] == nd) { 
			--par->mNumChildren;
			for (;i < par->mNumChildren;++i) {
				par->mChildren[i] = par->mChildren[i+1];
			}
			delete nd;
			break;
		}
	}
}

// ------------------------------------------------------------------------------------------------
// Read a multi-part Q3 player model
bool MD3Importer::ReadMultipartFile()
{
	// check whether the file name contains a common postfix, e.g lower_2.md3
	std::string::size_type s = filename.find_last_of('_'), t = filename.find_last_of('.');

	if (t == std::string::npos)
		t = filename.size();
	if (s == std::string::npos)
		s = t;

	const std::string mod_filename = filename.substr(0,s);
	const std::string suffix = filename.substr(s,t-s);

	if (mod_filename == "lower" || mod_filename == "upper" || mod_filename == "head"){
		const std::string lower = path + "lower" + suffix + ".md3";
		const std::string upper = path + "upper" + suffix + ".md3";
		const std::string head  = path + "head"  + suffix + ".md3";

		aiScene* scene_upper = NULL;
		aiScene* scene_lower = NULL;
		aiScene* scene_head = NULL;
		std::string failure;

		aiNode* tag_torso, *tag_head;
		std::vector<AttachmentInfo> attach;

		DefaultLogger::get()->info("Multi part MD3 player model: lower, upper and head parts are joined");

		// ensure we won't try to load ourselves recursively
		BatchLoader::PropertyMap props;
		SetGenericProperty( props.ints, AI_CONFIG_IMPORT_MD3_HANDLE_MULTIPART, 0);

		// now read these three files
		BatchLoader batch(mIOHandler);
		const unsigned int _lower = batch.AddLoadRequest(lower,0,&props);
		const unsigned int _upper = batch.AddLoadRequest(upper,0,&props);
		const unsigned int _head  = batch.AddLoadRequest(head,0,&props);
		batch.LoadAll();

		// now construct a dummy scene to place these three parts in
		aiScene* master   = new aiScene();
		aiNode* nd = master->mRootNode = new aiNode();
		nd->mName.Set("<MD3_Player>");

		// ... and get them. We need all of them.
		scene_lower = batch.GetImport(_lower);
		if (!scene_lower) {
			DefaultLogger::get()->error("M3D: Failed to read multi part model, lower.md3 fails to load");
			failure = "lower";
			goto error_cleanup;
		}

		scene_upper = batch.GetImport(_upper);
		if (!scene_upper) {
			DefaultLogger::get()->error("M3D: Failed to read multi part model, upper.md3 fails to load");
			failure = "upper";
			goto error_cleanup;
		}

		scene_head  = batch.GetImport(_head);
		if (!scene_head) {
			DefaultLogger::get()->error("M3D: Failed to read multi part model, head.md3 fails to load");
			failure = "head";
			goto error_cleanup;
		}

		// build attachment infos. search for typical Q3 tags

		// original root
		scene_lower->mRootNode->mName.Set("lower");
		attach.push_back(AttachmentInfo(scene_lower, nd));

		// tag_torso
		tag_torso = scene_lower->mRootNode->FindNode("tag_torso");
		if (!tag_torso) {
			DefaultLogger::get()->error("M3D: Failed to find attachment tag for multi part model: tag_torso expected");
			goto error_cleanup;
		}
		scene_upper->mRootNode->mName.Set("upper");
		attach.push_back(AttachmentInfo(scene_upper,tag_torso));

		// tag_head
		tag_head = scene_upper->mRootNode->FindNode("tag_head");
		if (!tag_head) {
			DefaultLogger::get()->error("M3D: Failed to find attachment tag for multi part model: tag_head expected");
			goto error_cleanup;
		}
		scene_head->mRootNode->mName.Set("head");
		attach.push_back(AttachmentInfo(scene_head,tag_head));

		// Remove tag_head and tag_torso from all other model parts ...
		// this ensures (together with AI_INT_MERGE_SCENE_GEN_UNIQUE_NAMES_IF_NECESSARY)
		// that tag_torso/tag_head is also the name of the (unique) output node
		RemoveSingleNodeFromList (scene_upper->mRootNode->FindNode("tag_torso"));
		RemoveSingleNodeFromList (scene_head-> mRootNode->FindNode("tag_head" ));

		// Undo the rotations which we applied to the coordinate systems. We're
		// working in global Quake space here
		scene_head->mRootNode->mTransformation  = aiMatrix4x4();
		scene_lower->mRootNode->mTransformation = aiMatrix4x4();
		scene_upper->mRootNode->mTransformation = aiMatrix4x4();

		// and merge the scenes
		SceneCombiner::MergeScenes(&mScene,master, attach,
			AI_INT_MERGE_SCENE_GEN_UNIQUE_NAMES          |
			AI_INT_MERGE_SCENE_GEN_UNIQUE_MATNAMES       |
			AI_INT_MERGE_SCENE_RESOLVE_CROSS_ATTACHMENTS |
			(!configSpeedFlag ? AI_INT_MERGE_SCENE_GEN_UNIQUE_NAMES_IF_NECESSARY : 0));

		// Now rotate the whole scene 90 degrees around the x axis to convert to internal coordinate system
		mScene->mRootNode->mTransformation = aiMatrix4x4(1.f,0.f,0.f,0.f,
			0.f,0.f,1.f,0.f,0.f,-1.f,0.f,0.f,0.f,0.f,0.f,1.f);

		return true;

error_cleanup:
		delete scene_upper;
		delete scene_lower;
		delete scene_head;
		delete master;

		if (failure == mod_filename) {
			throw DeadlyImportError("MD3: failure to read multipart host file");
		}
	}
	return false;
}

// ------------------------------------------------------------------------------------------------
// Convert a MD3 path to a proper value
void MD3Importer::ConvertPath(const char* texture_name, const char* header_name, std::string& out) const
{
	// If the MD3's internal path itself and the given path are using
	// the same directory, remove it completely to get right output paths.
	const char* end1 = ::strrchr(header_name,'\\');
	if (!end1)end1   = ::strrchr(header_name,'/');

	const char* end2 = ::strrchr(texture_name,'\\');
	if (!end2)end2   = ::strrchr(texture_name,'/');

	// HACK: If the paths starts with "models", ignore the
	// next two hierarchy levels, it specifies just the model name.
	// Ignored by Q3, it might be not equal to the real model location.
	if (end2)	{

		size_t len2;
		const size_t len1 = (size_t)(end1 - header_name);
		if (!ASSIMP_strincmp(texture_name,"models",6) && (texture_name[6] == '/' || texture_name[6] == '\\')) {
			len2 = 6; // ignore the seventh - could be slash or backslash

			if (!header_name[0]) {
				// Use the file name only
				out = end2+1;
				return;
			}
		}
		else len2 = std::min (len1, (size_t)(end2 - texture_name ));
		if (!ASSIMP_strincmp(texture_name,header_name,len2)) {
			// Use the file name only
			out = end2+1;
			return;
		}
	}
	// Use the full path
	out = texture_name;
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void MD3Importer::InternReadFile( const std::string& pFile, 
	aiScene* pScene, IOSystem* pIOHandler)
{
	mFile = pFile;
	mScene = pScene;
	mIOHandler = pIOHandler;

	// get base path and file name
	// todo ... move to PathConverter
	std::string::size_type s = mFile.find_last_of("/\\");
	if (s == std::string::npos) {
		s = 0;
	}
	else ++s;
	filename = mFile.substr(s), path = mFile.substr(0,s);
	for( std::string::iterator it = filename .begin(); it != filename.end(); ++it)
		*it = tolower( *it);

	// Load multi-part model file, if necessary
	if (configHandleMP) {
		if (ReadMultipartFile())
			return;
	}

	boost::scoped_ptr<IOStream> file( pIOHandler->Open( pFile));

	// Check whether we can read from the file
	if( file.get() == NULL)
		throw DeadlyImportError( "Failed to open MD3 file " + pFile + ".");

	// Check whether the md3 file is large enough to contain the header
	fileSize = (unsigned int)file->FileSize();
	if( fileSize < sizeof(MD3::Header))
		throw DeadlyImportError( "MD3 File is too small.");

	// Allocate storage and copy the contents of the file to a memory buffer
	std::vector<unsigned char> mBuffer2 (fileSize);
	file->Read( &mBuffer2[0], 1, fileSize);
	mBuffer = &mBuffer2[0];

	pcHeader = (BE_NCONST MD3::Header*)mBuffer;

	// Ensure correct endianess
#ifdef AI_BUILD_BIG_ENDIAN

	AI_SWAP4(pcHeader->VERSION);
	AI_SWAP4(pcHeader->FLAGS);
	AI_SWAP4(pcHeader->IDENT);
	AI_SWAP4(pcHeader->NUM_FRAMES);
	AI_SWAP4(pcHeader->NUM_SKINS);
	AI_SWAP4(pcHeader->NUM_SURFACES);
	AI_SWAP4(pcHeader->NUM_TAGS);
	AI_SWAP4(pcHeader->OFS_EOF);
	AI_SWAP4(pcHeader->OFS_FRAMES);
	AI_SWAP4(pcHeader->OFS_SURFACES);
	AI_SWAP4(pcHeader->OFS_TAGS);

#endif

	// Validate the file header
	ValidateHeaderOffsets();

	// Navigate to the list of surfaces
	BE_NCONST MD3::Surface* pcSurfaces = (BE_NCONST MD3::Surface*)(mBuffer + pcHeader->OFS_SURFACES);

	// Navigate to the list of tags
	BE_NCONST MD3::Tag* pcTags = (BE_NCONST MD3::Tag*)(mBuffer + pcHeader->OFS_TAGS);

	// Allocate output storage
	pScene->mNumMeshes = pcHeader->NUM_SURFACES;
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];

	pScene->mNumMaterials = pcHeader->NUM_SURFACES;
	pScene->mMaterials = new aiMaterial*[pScene->mNumMeshes];

	// Set arrays to zero to ensue proper destruction if an exception is raised
	::memset(pScene->mMeshes,0,pScene->mNumMeshes*sizeof(aiMesh*));
	::memset(pScene->mMaterials,0,pScene->mNumMaterials*sizeof(aiMaterial*));

	// Now read possible skins from .skin file
	Q3Shader::SkinData skins;
	ReadSkin(skins);

	// And check whether we can locate a shader file for this model
	Q3Shader::ShaderData shaders;
	ReadShader(shaders);

	// Adjust all texture paths in the shader
	const char* header_name = pcHeader->NAME;
	if (!shaders.blocks.empty()) {
		for (std::list< Q3Shader::ShaderDataBlock >::iterator dit = shaders.blocks.begin(); dit != shaders.blocks.end(); ++dit) {
			ConvertPath((*dit).name.c_str(),header_name,(*dit).name);

			for (std::list< Q3Shader::ShaderMapBlock >::iterator mit = (*dit).maps.begin(); mit != (*dit).maps.end(); ++mit) {
				ConvertPath((*mit).name.c_str(),header_name,(*mit).name);
			}
		}
	}

	// Read all surfaces from the file
	unsigned int iNum = pcHeader->NUM_SURFACES;
	unsigned int iNumMaterials = 0;
	while (iNum-- > 0)	{

		// Ensure correct endianess
#ifdef AI_BUILD_BIG_ENDIAN

		AI_SWAP4(pcSurfaces->FLAGS);
		AI_SWAP4(pcSurfaces->IDENT);
		AI_SWAP4(pcSurfaces->NUM_FRAMES);
		AI_SWAP4(pcSurfaces->NUM_SHADER);
		AI_SWAP4(pcSurfaces->NUM_TRIANGLES);
		AI_SWAP4(pcSurfaces->NUM_VERTICES);
		AI_SWAP4(pcSurfaces->OFS_END);
		AI_SWAP4(pcSurfaces->OFS_SHADERS);
		AI_SWAP4(pcSurfaces->OFS_ST);
		AI_SWAP4(pcSurfaces->OFS_TRIANGLES);
		AI_SWAP4(pcSurfaces->OFS_XYZNORMAL);

#endif

		// Validate the surface header
		ValidateSurfaceHeaderOffsets(pcSurfaces);

		// Navigate to the vertex list of the surface
		BE_NCONST MD3::Vertex* pcVertices = (BE_NCONST MD3::Vertex*)
			(((uint8_t*)pcSurfaces) + pcSurfaces->OFS_XYZNORMAL);

		// Navigate to the triangle list of the surface
		BE_NCONST MD3::Triangle* pcTriangles = (BE_NCONST MD3::Triangle*)
			(((uint8_t*)pcSurfaces) + pcSurfaces->OFS_TRIANGLES);

		// Navigate to the texture coordinate list of the surface
		BE_NCONST MD3::TexCoord* pcUVs = (BE_NCONST MD3::TexCoord*)
			(((uint8_t*)pcSurfaces) + pcSurfaces->OFS_ST);

		// Navigate to the shader list of the surface
		BE_NCONST MD3::Shader* pcShaders = (BE_NCONST MD3::Shader*)
			(((uint8_t*)pcSurfaces) + pcSurfaces->OFS_SHADERS);

		// If the submesh is empty ignore it
		if (0 == pcSurfaces->NUM_VERTICES || 0 == pcSurfaces->NUM_TRIANGLES)
		{
			pcSurfaces = (BE_NCONST MD3::Surface*)(((uint8_t*)pcSurfaces) + pcSurfaces->OFS_END);
			pScene->mNumMeshes--;
			continue;
		}

		// Allocate output mesh
		pScene->mMeshes[iNum] = new aiMesh();
		aiMesh* pcMesh = pScene->mMeshes[iNum];

		std::string _texture_name;
		const char* texture_name = NULL;

		// Check whether we have a texture record for this surface in the .skin file
		std::list< Q3Shader::SkinData::TextureEntry >::iterator it = std::find( 
			skins.textures.begin(), skins.textures.end(), pcSurfaces->NAME );

		if (it != skins.textures.end()) {
			texture_name = &*( _texture_name = (*it).second).begin();
			DefaultLogger::get()->debug("MD3: Assigning skin texture " + (*it).second + " to surface " + pcSurfaces->NAME);
			(*it).resolved = true; // mark entry as resolved
		}

		// Get the first shader (= texture?) assigned to the surface
		if (!texture_name && pcSurfaces->NUM_SHADER)	{
			texture_name = pcShaders->NAME;
		}

		std::string convertedPath;
		if (texture_name) {
			ConvertPath(texture_name,header_name,convertedPath);
		}

		const Q3Shader::ShaderDataBlock* shader = NULL;

		// Now search the current shader for a record with this name (
		// excluding texture file extension)
		if (!shaders.blocks.empty()) {

			std::string::size_type s = convertedPath.find_last_of('.');
			if (s == std::string::npos)
				s = convertedPath.length();

			const std::string without_ext = convertedPath.substr(0,s);
			std::list< Q3Shader::ShaderDataBlock >::const_iterator dit = std::find(shaders.blocks.begin(),shaders.blocks.end(),without_ext);
			if (dit != shaders.blocks.end()) {
				// Hurra, wir haben einen. Tolle Sache.
				shader = &*dit;
				DefaultLogger::get()->info("Found shader record for " +without_ext );
			}
			else DefaultLogger::get()->warn("Unable to find shader record for " +without_ext );
		}

		aiMaterial* pcHelper = new aiMaterial();

		const int iMode = (int)aiShadingMode_Gouraud;
		pcHelper->AddProperty<int>(&iMode, 1, AI_MATKEY_SHADING_MODEL);

		// Add a small ambient color value - Quake 3 seems to have one
		aiColor3D clr;
		clr.b = clr.g = clr.r = 0.05f;
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_AMBIENT);

		clr.b = clr.g = clr.r = 1.0f;
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_DIFFUSE);
		pcHelper->AddProperty<aiColor3D>(&clr, 1,AI_MATKEY_COLOR_SPECULAR);

		// use surface name + skin_name as material name
		aiString name;
		name.Set("MD3_[" + configSkinFile + "][" + pcSurfaces->NAME + "]");
		pcHelper->AddProperty(&name,AI_MATKEY_NAME);

		if (!shader) {
			// Setup dummy texture file name to ensure UV coordinates are kept during postprocessing
			aiString szString;
			if (convertedPath.length())	{
				szString.Set(convertedPath);
			}
			else	{
				DefaultLogger::get()->warn("Texture file name has zero length. Using default name");
				szString.Set("dummy_texture.bmp");
			}
			pcHelper->AddProperty(&szString,AI_MATKEY_TEXTURE_DIFFUSE(0));

			// prevent transparency by default
			int no_alpha = aiTextureFlags_IgnoreAlpha;
			pcHelper->AddProperty(&no_alpha,1,AI_MATKEY_TEXFLAGS_DIFFUSE(0));
		}
		else {
			Q3Shader::ConvertShaderToMaterial(pcHelper,*shader);
		}

		pScene->mMaterials[iNumMaterials] = (aiMaterial*)pcHelper;
		pcMesh->mMaterialIndex = iNumMaterials++;

			// Ensure correct endianess
#ifdef AI_BUILD_BIG_ENDIAN

		for (uint32_t i = 0; i < pcSurfaces->NUM_VERTICES;++i)	{
			AI_SWAP2( pcVertices[i].NORMAL );
			AI_SWAP2( pcVertices[i].X );
			AI_SWAP2( pcVertices[i].Y );
			AI_SWAP2( pcVertices[i].Z );

			AI_SWAP4( pcUVs[i].U );
			AI_SWAP4( pcUVs[i].U );
		}
		for (uint32_t i = 0; i < pcSurfaces->NUM_TRIANGLES;++i)	{
			AI_SWAP4(pcTriangles[i].INDEXES[0]);
			AI_SWAP4(pcTriangles[i].INDEXES[1]);
			AI_SWAP4(pcTriangles[i].INDEXES[2]);
		}

#endif

		// Fill mesh information
		pcMesh->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;

		pcMesh->mNumVertices		= pcSurfaces->NUM_TRIANGLES*3;
		pcMesh->mNumFaces			= pcSurfaces->NUM_TRIANGLES;
		pcMesh->mFaces				= new aiFace[pcSurfaces->NUM_TRIANGLES];
		pcMesh->mNormals			= new aiVector3D[pcMesh->mNumVertices];
		pcMesh->mVertices			= new aiVector3D[pcMesh->mNumVertices];
		pcMesh->mTextureCoords[0]	= new aiVector3D[pcMesh->mNumVertices];
		pcMesh->mNumUVComponents[0] = 2;

		// Fill in all triangles
		unsigned int iCurrent = 0;
		for (unsigned int i = 0; i < (unsigned int)pcSurfaces->NUM_TRIANGLES;++i)	{
			pcMesh->mFaces[i].mIndices = new unsigned int[3];
			pcMesh->mFaces[i].mNumIndices = 3;

			//unsigned int iTemp = iCurrent;
			for (unsigned int c = 0; c < 3;++c,++iCurrent)	{
				pcMesh->mFaces[i].mIndices[c] = iCurrent;

				// Read vertices
				aiVector3D& vec = pcMesh->mVertices[iCurrent];
				vec.x = pcVertices[ pcTriangles->INDEXES[c]].X*AI_MD3_XYZ_SCALE;
				vec.y = pcVertices[ pcTriangles->INDEXES[c]].Y*AI_MD3_XYZ_SCALE;
				vec.z = pcVertices[ pcTriangles->INDEXES[c]].Z*AI_MD3_XYZ_SCALE;

				// Convert the normal vector to uncompressed float3 format
				aiVector3D& nor = pcMesh->mNormals[iCurrent];
				LatLngNormalToVec3(pcVertices[pcTriangles->INDEXES[c]].NORMAL,(float*)&nor);

				// Read texture coordinates
				pcMesh->mTextureCoords[0][iCurrent].x = pcUVs[ pcTriangles->INDEXES[c]].U;
				pcMesh->mTextureCoords[0][iCurrent].y = 1.0f-pcUVs[ pcTriangles->INDEXES[c]].V;
			}
			// Flip face order if necessary
			if (!shader || shader->cull == Q3Shader::CULL_CW) {
				std::swap(pcMesh->mFaces[i].mIndices[2],pcMesh->mFaces[i].mIndices[1]);
			}
			pcTriangles++;
		}
	
		// Go to the next surface
		pcSurfaces = (BE_NCONST MD3::Surface*)(((unsigned char*)pcSurfaces) + pcSurfaces->OFS_END);
	}

	// For debugging purposes: check whether we found matches for all entries in the skins file
	if (!DefaultLogger::isNullLogger()) {
		for (std::list< Q3Shader::SkinData::TextureEntry>::const_iterator it = skins.textures.begin();it != skins.textures.end(); ++it) {
			if (!(*it).resolved) {
				DefaultLogger::get()->error("MD3: Failed to match skin " + (*it).first + " to surface " + (*it).second);
			}
		}
	}

	if (!pScene->mNumMeshes)
		throw DeadlyImportError( "MD3: File contains no valid mesh");
	pScene->mNumMaterials = iNumMaterials;

	// Now we need to generate an empty node graph
	pScene->mRootNode = new aiNode("<MD3Root>");
	pScene->mRootNode->mNumMeshes = pScene->mNumMeshes;
	pScene->mRootNode->mMeshes = new unsigned int[pScene->mNumMeshes];

	// Attach tiny children for all tags
	if (pcHeader->NUM_TAGS) {
		pScene->mRootNode->mNumChildren = pcHeader->NUM_TAGS;
		pScene->mRootNode->mChildren = new aiNode*[pcHeader->NUM_TAGS];

		for (unsigned int i = 0; i < pcHeader->NUM_TAGS; ++i, ++pcTags) {

			aiNode* nd = pScene->mRootNode->mChildren[i] = new aiNode();
			nd->mName.Set((const char*)pcTags->NAME);
			nd->mParent = pScene->mRootNode;

			AI_SWAP4(pcTags->origin.x);
			AI_SWAP4(pcTags->origin.y);
			AI_SWAP4(pcTags->origin.z);

			// Copy local origin, again flip z,y
			nd->mTransformation.a4 = pcTags->origin.x;
			nd->mTransformation.b4 = pcTags->origin.y;
			nd->mTransformation.c4 = pcTags->origin.z;

			// Copy rest of transformation (need to transpose to match row-order matrix)
			for (unsigned int a = 0; a < 3;++a) {
				for (unsigned int m = 0; m < 3;++m) {
					nd->mTransformation[m][a] = pcTags->orientation[a][m];
					AI_SWAP4(nd->mTransformation[m][a]);
				}
			}
		}
	}

	for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
		pScene->mRootNode->mMeshes[i] = i;

	// Now rotate the whole scene 90 degrees around the x axis to convert to internal coordinate system
	pScene->mRootNode->mTransformation = aiMatrix4x4(1.f,0.f,0.f,0.f,
		0.f,0.f,1.f,0.f,0.f,-1.f,0.f,0.f,0.f,0.f,0.f,1.f);
}

#endif // !! ASSIMP_BUILD_NO_MD3_IMPORTER