/*
---------------------------------------------------------------------------
Open Asset Import Library (assimp)
---------------------------------------------------------------------------

Copyright (c) 2006-2012, assimp team

All rights reserved.

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* 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
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  derived from this software without specific prior
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*/

/** @file  IRRLoader.cpp
 *  @brief Implementation of the Irr importer class 
 */

#include "AssimpPCH.h"

#include "IRRLoader.h"
#include "ParsingUtils.h"
#include "fast_atof.h"
#include "GenericProperty.h"

#include "SceneCombiner.h"
#include "StandardShapes.h"
#include "Importer.h"

// We need boost::common_factor to compute the lcm/gcd of a number
#include <boost/math/common_factor_rt.hpp>

using namespace Assimp;
using namespace irr;
using namespace irr::io;


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

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

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool IRRImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const
{
	/* NOTE: A simple check for the file extension is not enough
	 * here. Irrmesh and irr are easy, but xml is too generic
	 * and could be collada, too. So we need to open the file and
	 * search for typical tokens.
	 */
	const std::string extension = GetExtension(pFile);
	
	if (extension == "irr")return true;
	else if (extension == "xml" || checkSig)
	{
		/*  If CanRead() is called in order to check whether we
		 *  support a specific file extension in general pIOHandler
		 *  might be NULL and it's our duty to return true here.
		 */
		if (!pIOHandler)return true;
		const char* tokens[] = {"irr_scene"};
		return SearchFileHeaderForToken(pIOHandler,pFile,tokens,1);
	}
	return false;
}

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

// ------------------------------------------------------------------------------------------------
void IRRImporter::SetupProperties(const Importer* pImp)
{
	// read the output frame rate of all node animation channels
	fps = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_IRR_ANIM_FPS,100);
	if (fps < 10.)	{
		DefaultLogger::get()->error("IRR: Invalid FPS configuration");
		fps = 100;
	}

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

// ------------------------------------------------------------------------------------------------
// Build a mesh tha consists of a single squad (a side of a skybox)
aiMesh* IRRImporter::BuildSingleQuadMesh(const SkyboxVertex& v1,
	const SkyboxVertex& v2,
	const SkyboxVertex& v3,
	const SkyboxVertex& v4)
{
	// allocate and prepare the mesh
	aiMesh* out = new aiMesh();

	out->mPrimitiveTypes = aiPrimitiveType_POLYGON;
	out->mNumFaces = 1;

	// build the face
	out->mFaces    = new aiFace[1];
	aiFace& face   = out->mFaces[0];
	
	face.mNumIndices = 4;
	face.mIndices    = new unsigned int[4];
	for (unsigned int i = 0; i < 4;++i)
		face.mIndices[i] = i;

	out->mNumVertices = 4;

	// copy vertex positions
	aiVector3D* vec = out->mVertices = new aiVector3D[4];
	*vec++ = v1.position;
	*vec++ = v2.position;
	*vec++ = v3.position;
	*vec   = v4.position;

	// copy vertex normals
	vec = out->mNormals = new aiVector3D[4];
	*vec++ = v1.normal;
	*vec++ = v2.normal;
	*vec++ = v3.normal;
	*vec   = v4.normal;

	// copy texture coordinates
	vec = out->mTextureCoords[0] = new aiVector3D[4];
	*vec++ = v1.uv;
	*vec++ = v2.uv;
	*vec++ = v3.uv;
	*vec   = v4.uv;
	return out;
}

// ------------------------------------------------------------------------------------------------
void IRRImporter::BuildSkybox(std::vector<aiMesh*>& meshes, std::vector<aiMaterial*> materials)
{
	// Update the material of the skybox - replace the name and disable shading for skyboxes.
	for (unsigned int i = 0; i < 6;++i)	{
		aiMaterial* out = ( aiMaterial* ) (*(materials.end()-(6-i)));

		aiString s;
		s.length = ::sprintf( s.data, "SkyboxSide_%i",i );
		out->AddProperty(&s,AI_MATKEY_NAME);

		int shading = aiShadingMode_NoShading;
		out->AddProperty(&shading,1,AI_MATKEY_SHADING_MODEL);
	}

	// Skyboxes are much more difficult. They are represented
	// by six single planes with different textures, so we'll
	// need to build six meshes.

	const float l = 10.f; // the size used by Irrlicht

	// FRONT SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex(-l,-l,-l,  0, 0, 1,   1.f,1.f),
		SkyboxVertex( l,-l,-l,  0, 0, 1,   0.f,1.f),
		SkyboxVertex( l, l,-l,  0, 0, 1,   0.f,0.f),
		SkyboxVertex(-l, l,-l,  0, 0, 1,   1.f,0.f)) );
	meshes.back()->mMaterialIndex = materials.size()-6u;

	// LEFT SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex( l,-l,-l,  -1, 0, 0,   1.f,1.f),
		SkyboxVertex( l,-l, l,  -1, 0, 0,   0.f,1.f),
		SkyboxVertex( l, l, l,  -1, 0, 0,   0.f,0.f),
		SkyboxVertex( l, l,-l,  -1, 0, 0,   1.f,0.f)) );
	meshes.back()->mMaterialIndex = materials.size()-5u;

	// BACK SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex( l,-l, l,  0, 0, -1,   1.f,1.f),
		SkyboxVertex(-l,-l, l,  0, 0, -1,   0.f,1.f),
		SkyboxVertex(-l, l, l,  0, 0, -1,   0.f,0.f),
		SkyboxVertex( l, l, l,  0, 0, -1,   1.f,0.f)) );
	meshes.back()->mMaterialIndex = materials.size()-4u;

	// RIGHT SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex(-l,-l, l,  1, 0, 0,   1.f,1.f),
		SkyboxVertex(-l,-l,-l,  1, 0, 0,   0.f,1.f),
		SkyboxVertex(-l, l,-l,  1, 0, 0,   0.f,0.f),
		SkyboxVertex(-l, l, l,  1, 0, 0,   1.f,0.f)) );
	meshes.back()->mMaterialIndex = materials.size()-3u;

	// TOP SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex( l, l,-l,  0, -1, 0,   1.f,1.f),
		SkyboxVertex( l, l, l,  0, -1, 0,   0.f,1.f),
		SkyboxVertex(-l, l, l,  0, -1, 0,   0.f,0.f),
		SkyboxVertex(-l, l,-l,  0, -1, 0,   1.f,0.f)) );
	meshes.back()->mMaterialIndex = materials.size()-2u;

	// BOTTOM SIDE
	meshes.push_back( BuildSingleQuadMesh( 
		SkyboxVertex( l,-l, l,  0,  1, 0,   0.f,0.f),
		SkyboxVertex( l,-l,-l,  0,  1, 0,   1.f,0.f),
		SkyboxVertex(-l,-l,-l,  0,  1, 0,   1.f,1.f),
		SkyboxVertex(-l,-l, l,  0,  1, 0,   0.f,1.f)) );
	meshes.back()->mMaterialIndex = materials.size()-1u;
}

// ------------------------------------------------------------------------------------------------
void IRRImporter::CopyMaterial(std::vector<aiMaterial*>& materials,
	std::vector< std::pair<aiMaterial*, unsigned int> >& inmaterials,
	unsigned int& defMatIdx,
	aiMesh* mesh)
{
	if (inmaterials.empty())	{
		// Do we have a default material? If not we need to create one
		if (UINT_MAX == defMatIdx)
		{
			defMatIdx = (unsigned int)materials.size();
			aiMaterial* mat = new aiMaterial();

			aiString s;
			s.Set(AI_DEFAULT_MATERIAL_NAME);
			mat->AddProperty(&s,AI_MATKEY_NAME);

			aiColor3D c(0.6f,0.6f,0.6f);
			mat->AddProperty(&c,1,AI_MATKEY_COLOR_DIFFUSE);
		}
		mesh->mMaterialIndex = defMatIdx;
		return;
	}
	else if (inmaterials.size() > 1)	{
		DefaultLogger::get()->info("IRR: Skipping additional materials");
	}

	mesh->mMaterialIndex = (unsigned int)materials.size();
	materials.push_back(inmaterials[0].first);
}


// ------------------------------------------------------------------------------------------------
inline int ClampSpline(int idx, int size)
{
	return ( idx<0 ? size+idx : ( idx>=size ? idx-size : idx ) );
}

// ------------------------------------------------------------------------------------------------
inline void FindSuitableMultiple(int& angle)
{
	if (angle < 3)angle = 3;
	else if (angle < 10) angle = 10;
	else if (angle < 20) angle = 20;
	else if (angle < 30) angle = 30;
	else
	{
	}
}

// ------------------------------------------------------------------------------------------------
void IRRImporter::ComputeAnimations(Node* root, aiNode* real, std::vector<aiNodeAnim*>& anims)
{
	ai_assert(NULL != root && NULL != real);

	// XXX totally WIP - doesn't produce proper results, need to evaluate
	// whether there's any use for Irrlicht's proprietary scene format
	// outside Irrlicht ...

	if (root->animators.empty()) {
		return;
	}
	unsigned int total = 0;
	for (std::list<Animator>::iterator it = root->animators.begin();it != root->animators.end(); ++it)	{
		if ((*it).type == Animator::UNKNOWN || (*it).type == Animator::OTHER)	{
			DefaultLogger::get()->warn("IRR: Skipping unknown or unsupported animator");
			continue;
		}
		++total;
	}
	if (!total)return;
	else if (1 == total)	{
		DefaultLogger::get()->warn("IRR: Adding dummy nodes to simulate multiple animators");
	}

	// NOTE: 1 tick == i millisecond

	unsigned int cur = 0;
	for (std::list<Animator>::iterator it = root->animators.begin();
		it != root->animators.end(); ++it)
	{
		if ((*it).type == Animator::UNKNOWN || (*it).type == Animator::OTHER)continue;

		Animator& in = *it ;
		aiNodeAnim* anim = new aiNodeAnim();

		if (cur != total-1)	{
			// Build a new name - a prefix instead of a suffix because it is
			// easier to check against
			anim->mNodeName.length = ::sprintf(anim->mNodeName.data,
				"$INST_DUMMY_%i_%s",total-1,
				(root->name.length() ? root->name.c_str() : ""));

			// we'll also need to insert a dummy in the node hierarchy.
			aiNode* dummy = new aiNode();

			for (unsigned int i = 0; i < real->mParent->mNumChildren;++i)
				if (real->mParent->mChildren[i] == real)
					real->mParent->mChildren[i] = dummy;

			dummy->mParent = real->mParent;
			dummy->mName = anim->mNodeName;

			dummy->mNumChildren = 1;
			dummy->mChildren = new aiNode*[dummy->mNumChildren];
			dummy->mChildren[0] = real;

			// the transformation matrix of the dummy node is the identity

			real->mParent = dummy;
		}
		else anim->mNodeName.Set(root->name);
		++cur;

		switch (in.type)	{
		case Animator::ROTATION:
			{
				// -----------------------------------------------------
				// find out how long a full rotation will take
				// This is the least common multiple of 360.f and all 
				// three euler angles. Although we'll surely find a 
				// possible multiple (haha) it could be somewhat large
				// for our purposes. So we need to modify the angles
				// here in order to get good results.
				// -----------------------------------------------------
				int angles[3];
				angles[0] = (int)(in.direction.x*100);
				angles[1] = (int)(in.direction.y*100);
				angles[2] = (int)(in.direction.z*100);

				angles[0] %= 360;
				angles[1] %= 360;
				angles[2] %= 360;

				if ((angles[0]*angles[1]) && (angles[1]*angles[2]))
				{
					FindSuitableMultiple(angles[0]);
					FindSuitableMultiple(angles[1]);
					FindSuitableMultiple(angles[2]);
				}

				int lcm = 360;

				if (angles[0])
					lcm  = boost::math::lcm(lcm,angles[0]);

				if (angles[1])
					lcm  = boost::math::lcm(lcm,angles[1]);

				if (angles[2])
					lcm  = boost::math::lcm(lcm,angles[2]);

				if (360 == lcm)
					break;

#if 0
				// This can be a division through zero, but we don't care
				float f1 = (float)lcm / angles[0];
				float f2 = (float)lcm / angles[1];
				float f3 = (float)lcm / angles[2];
#endif

				// find out how many time units we'll need for the finest
				// track (in seconds) - this defines the number of output
				// keys (fps * seconds)
				float max  = 0.f;
				if (angles[0])
					max = (float)lcm / angles[0];
				if (angles[1])
					max = std::max(max, (float)lcm / angles[1]);
				if (angles[2])
					max = std::max(max, (float)lcm / angles[2]);

				anim->mNumRotationKeys = (unsigned int)(max*fps);
				anim->mRotationKeys = new aiQuatKey[anim->mNumRotationKeys];

				// begin with a zero angle
				aiVector3D angle;
				for (unsigned int i = 0; i < anim->mNumRotationKeys;++i)
				{
					// build the quaternion for the given euler angles
					aiQuatKey& q = anim->mRotationKeys[i];

					q.mValue = aiQuaternion(angle.x, angle.y, angle.z);
					q.mTime = (double)i;

					// increase the angle
					angle += in.direction;
				}

				// This animation is repeated and repeated ...
				anim->mPostState = anim->mPreState = aiAnimBehaviour_REPEAT;
			}
			break;

		case Animator::FLY_CIRCLE:
			{
				// -----------------------------------------------------
				// Find out how much time we'll need to perform a 
				// full circle. 
				// -----------------------------------------------------
				const double seconds = (1. / in.speed) / 1000.;
				const double tdelta = 1000. / fps;

				anim->mNumPositionKeys = (unsigned int) (fps * seconds);
				anim->mPositionKeys = new aiVectorKey[anim->mNumPositionKeys];

				// from Irrlicht, what else should we do than copying it?
				aiVector3D vecU,vecV;
				if (in.direction.y)	{
					vecV = aiVector3D(50,0,0) ^ in.direction;
				}
				else vecV = aiVector3D(0,50,00) ^ in.direction;
				vecV.Normalize();
				vecU = (vecV ^ in.direction).Normalize();

				// build the output keys
				for (unsigned int i = 0; i < anim->mNumPositionKeys;++i)	{
					aiVectorKey& key = anim->mPositionKeys[i];
					key.mTime = i * tdelta;

					const float t = (float) ( in.speed * key.mTime );
					key.mValue = in.circleCenter  + in.circleRadius * ((vecU*math::cosf(t)) + (vecV*math::sinf(t)));
				}

				// This animation is repeated and repeated ...
				anim->mPostState = anim->mPreState = aiAnimBehaviour_REPEAT;
			}
			break;

		case Animator::FLY_STRAIGHT:
			{
				anim->mPostState = anim->mPreState = (in.loop ? aiAnimBehaviour_REPEAT : aiAnimBehaviour_CONSTANT);
				const double seconds = in.timeForWay / 1000.;
				const double tdelta = 1000. / fps;

				anim->mNumPositionKeys = (unsigned int) (fps * seconds);
				anim->mPositionKeys = new aiVectorKey[anim->mNumPositionKeys];

				aiVector3D diff = in.direction - in.circleCenter;
				const float lengthOfWay = diff.Length();
				diff.Normalize();

				const double timeFactor = lengthOfWay / in.timeForWay;

				// build the output keys
				for (unsigned int i = 0; i < anim->mNumPositionKeys;++i)	{
					aiVectorKey& key = anim->mPositionKeys[i];
					key.mTime = i * tdelta;
					key.mValue = in.circleCenter + diff * float(timeFactor * key.mTime);
				}
			}
			break;

		case Animator::FOLLOW_SPLINE:
			{
				// repeat outside the defined time range
				anim->mPostState = anim->mPreState = aiAnimBehaviour_REPEAT;
				const int size = (int)in.splineKeys.size();
				if (!size)	{
					// We have no point in the spline. That's bad. Really bad.
					DefaultLogger::get()->warn("IRR: Spline animators with no points defined");

					delete anim;anim = NULL;
					break;
				}
				else if (size == 1)	{
					// We have just one point in the spline so we don't need the full calculation
					anim->mNumPositionKeys = 1;
					anim->mPositionKeys = new aiVectorKey[anim->mNumPositionKeys];

					anim->mPositionKeys[0].mValue = in.splineKeys[0].mValue;
					anim->mPositionKeys[0].mTime  = 0.f;
					break;
				}

				unsigned int ticksPerFull = 15;
				anim->mNumPositionKeys = (unsigned int) ( ticksPerFull * fps );
				anim->mPositionKeys = new aiVectorKey[anim->mNumPositionKeys];

				for (unsigned int i = 0; i < anim->mNumPositionKeys;++i)
				{
					aiVectorKey& key = anim->mPositionKeys[i];

					const float dt = (i * in.speed * 0.001f );
					const float u = dt - math::floor(dt);
					const int idx = (int)math::floor(dt) % size;

					// get the 4 current points to evaluate the spline
					const aiVector3D& p0 = in.splineKeys[ ClampSpline( idx - 1, size ) ].mValue;
					const aiVector3D& p1 = in.splineKeys[ ClampSpline( idx + 0, size ) ].mValue; 
					const aiVector3D& p2 = in.splineKeys[ ClampSpline( idx + 1, size ) ].mValue; 
					const aiVector3D& p3 = in.splineKeys[ ClampSpline( idx + 2, size ) ].mValue;

					// compute polynomials
					const float u2 = u*u;
					const float u3 = u2*2;

					const float h1 = 2.0f * u3 - 3.0f * u2 + 1.0f;
					const float h2 = -2.0f * u3 + 3.0f * u3;
					const float h3 = u3 - 2.0f * u3;
					const float h4 = u3 - u2;

					// compute the spline tangents
					const aiVector3D t1 = ( p2 - p0 ) * in.tightness;
					aiVector3D t2 = ( p3 - p1 ) * in.tightness;

					// and use them to get the interpolated point
					t2 = (h1 * p1 + p2 * h2 + t1 * h3 + h4 * t2);

					// build a simple translation matrix from it
					key.mValue = t2;
					key.mTime  = (double) i;
				}
			}
			break;
		default:
			// UNKNOWN , OTHER
			break;
		};
		if (anim)	{
			anims.push_back(anim);
			++total;
		}
	}
}

// ------------------------------------------------------------------------------------------------
// This function is maybe more generic than we'd need it here
void SetupMapping (aiMaterial* mat, aiTextureMapping mode, const aiVector3D& axis = aiVector3D(0.f,0.f,-1.f))
{
	// Check whether there are texture properties defined - setup
	// the desired texture mapping mode for all of them and ignore
	// all UV settings we might encounter. WE HAVE NO UVS!

	std::vector<aiMaterialProperty*> p;
	p.reserve(mat->mNumProperties+1);

	for (unsigned int i = 0; i < mat->mNumProperties;++i)
	{
		aiMaterialProperty* prop = mat->mProperties[i];
		if (!::strcmp( prop->mKey.data, "$tex.file"))	{
			// Setup the mapping key
			aiMaterialProperty* m = new aiMaterialProperty();
			m->mKey.Set("$tex.mapping");
			m->mIndex    = prop->mIndex;
			m->mSemantic = prop->mSemantic;
			m->mType     = aiPTI_Integer;

			m->mDataLength = 4;
			m->mData = new char[4];
			*((int*)m->mData) = mode;

			p.push_back(prop);
			p.push_back(m);

			// Setup the mapping axis
			if (mode == aiTextureMapping_CYLINDER || mode == aiTextureMapping_PLANE || mode == aiTextureMapping_SPHERE)	{
				m = new aiMaterialProperty();
				m->mKey.Set("$tex.mapaxis");
				m->mIndex    = prop->mIndex;
				m->mSemantic = prop->mSemantic;
				m->mType     = aiPTI_Float;

				m->mDataLength = 12;
				m->mData = new char[12];
				*((aiVector3D*)m->mData) = axis;
				p.push_back(m);
			}
		}
		else if (! ::strcmp( prop->mKey.data, "$tex.uvwsrc"))	{
			delete mat->mProperties[i];
		}
		else p.push_back(prop);
	}

	if (p.empty())return;

	// rebuild the output array
	if (p.size() > mat->mNumAllocated)	{
		delete[] mat->mProperties;
		mat->mProperties = new aiMaterialProperty*[p.size()*2];

		mat->mNumAllocated = p.size()*2;
	}
	mat->mNumProperties = (unsigned int)p.size();
	::memcpy(mat->mProperties,&p[0],sizeof(void*)*mat->mNumProperties);
}

// ------------------------------------------------------------------------------------------------
void IRRImporter::GenerateGraph(Node* root,aiNode* rootOut ,aiScene* scene,
	BatchLoader& batch,
	std::vector<aiMesh*>&        meshes,
	std::vector<aiNodeAnim*>&    anims,
	std::vector<AttachmentInfo>& attach,
	std::vector<aiMaterial*>&	 materials,
	unsigned int&				 defMatIdx)
{
	unsigned int oldMeshSize = (unsigned int)meshes.size();
	//unsigned int meshTrafoAssign = 0;

	// Now determine the type of the node 
	switch (root->type)
	{
	case Node::ANIMMESH:
	case Node::MESH:
		{
			if (!root->meshPath.length())
				break;

			// Get the loaded mesh from the scene and add it to
			// the list of all scenes to be attached to the 
			// graph we're currently building
			aiScene* scene = batch.GetImport(root->id);
			if (!scene)	{
				DefaultLogger::get()->error("IRR: Unable to load external file: " + root->meshPath);
				break;
			}
			attach.push_back(AttachmentInfo(scene,rootOut));

			// Now combine the material we've loaded for this mesh
			// with the real materials we got from the file. As we
			// don't execute any pp-steps on the file, the numbers
			// should be equal. If they are not, we can impossibly
			// do this  ...
			if (root->materials.size() != (unsigned int)scene->mNumMaterials)	{
				DefaultLogger::get()->warn("IRR: Failed to match imported materials "
					"with the materials found in the IRR scene file");

				break;
			}
			for (unsigned int i = 0; i < scene->mNumMaterials;++i)	{
				// Delete the old material, we don't need it anymore
				delete scene->mMaterials[i];

				std::pair<aiMaterial*, unsigned int>& src = root->materials[i];
				scene->mMaterials[i] = src.first;
			}

			// NOTE: Each mesh should have exactly one material assigned,
			// but we do it in a separate loop if this behaviour changes
			// in future.
			for (unsigned int i = 0; i < scene->mNumMeshes;++i)	{
				// Process material flags 
				aiMesh* mesh = scene->mMeshes[i];


				// If "trans_vertex_alpha" mode is enabled, search all vertex colors 
				// and check whether they have a common alpha value. This is quite
				// often the case so we can simply extract it to a shared oacity
				// value.
				std::pair<aiMaterial*, unsigned int>& src = root->materials[mesh->mMaterialIndex];
				aiMaterial* mat = (aiMaterial*)src.first;

				if (mesh->HasVertexColors(0) && src.second & AI_IRRMESH_MAT_trans_vertex_alpha)
				{
					bool bdo = true;
					for (unsigned int a = 1; a < mesh->mNumVertices;++a)	{

						if (mesh->mColors[0][a].a != mesh->mColors[0][a-1].a)	{
							bdo = false;
							break;
						}
					}
					if (bdo)	{
						DefaultLogger::get()->info("IRR: Replacing mesh vertex alpha with common opacity");

						for (unsigned int a = 0; a < mesh->mNumVertices;++a)
							mesh->mColors[0][a].a = 1.f;

						mat->AddProperty(& mesh->mColors[0][0].a, 1, AI_MATKEY_OPACITY);
					}
				}

				// If we have a second texture coordinate set and a second texture
				// (either lightmap, normalmap, 2layered material) we need to
				// setup the correct UV index for it. The texture can either
				// be diffuse (lightmap & 2layer) or a normal map (normal & parallax)
				if (mesh->HasTextureCoords(1))	{

					int idx = 1;
					if (src.second & (AI_IRRMESH_MAT_solid_2layer | AI_IRRMESH_MAT_lightmap))	{
						mat->AddProperty(&idx,1,AI_MATKEY_UVWSRC_DIFFUSE(0));
					}
					else if (src.second & AI_IRRMESH_MAT_normalmap_solid)	{
						mat->AddProperty(&idx,1,AI_MATKEY_UVWSRC_NORMALS(0));
					}
				}
			}
		}
		break;

	case Node::LIGHT:
	case Node::CAMERA:

		// We're already finished with lights and cameras
		break;


	case Node::SPHERE:
		{
			// Generate the sphere model. Our input parameter to
			// the sphere generation algorithm is the number of
			// subdivisions of each triangle - but here we have
			// the number of poylgons on a specific axis. Just
			// use some hardcoded limits to approximate this ...
			unsigned int mul = root->spherePolyCountX*root->spherePolyCountY;
			if      (mul < 100)mul = 2;
			else if (mul < 300)mul = 3;
			else               mul = 4;

			meshes.push_back(StandardShapes::MakeMesh(mul,
				&StandardShapes::MakeSphere));

			// Adjust scaling
			root->scaling *= root->sphereRadius/2;

			// Copy one output material
			CopyMaterial(materials, root->materials, defMatIdx, meshes.back());

			// Now adjust this output material - if there is a first texture
			// set, setup spherical UV mapping around the Y axis.
			SetupMapping ( (aiMaterial*) materials.back(), aiTextureMapping_SPHERE);
		}
		break;

	case Node::CUBE:
		{
			// Generate an unit cube first
			meshes.push_back(StandardShapes::MakeMesh(
				&StandardShapes::MakeHexahedron));

			// Adjust scaling
			root->scaling *= root->sphereRadius;

			// Copy one output material
			CopyMaterial(materials, root->materials, defMatIdx, meshes.back());

			// Now adjust this output material - if there is a first texture
			// set, setup cubic UV mapping 
			SetupMapping ( (aiMaterial*) materials.back(), aiTextureMapping_BOX );
		}
		break;


	case Node::SKYBOX:
		{
			// A skybox is defined by six materials
			if (root->materials.size() < 6) {
				DefaultLogger::get()->error("IRR: There should be six materials for a skybox");
				break;
			}

			// copy those materials and generate 6 meshes for our new skybox
			materials.reserve(materials.size() + 6);
			for (unsigned int i = 0; i < 6;++i)
				materials.insert(materials.end(),root->materials[i].first);

			BuildSkybox(meshes,materials);

			// *************************************************************
			// Skyboxes will require a different code path for rendering,
			// so there must be a way for the user to add special support
			// for IRR skyboxes. We add a 'IRR.SkyBox_' prefix to the node.
			// *************************************************************
			root->name = "IRR.SkyBox_" + root->name;
			DefaultLogger::get()->info("IRR: Loading skybox, this will "
				"require special handling to be displayed correctly");
		}
		break;

	case Node::TERRAIN:
		{
			// to support terrains, we'd need to have a texture decoder
			DefaultLogger::get()->error("IRR: Unsupported node - TERRAIN");
		}
		break;
	default:
		// DUMMY
		break;
	};

	// Check whether we added a mesh (or more than one ...). In this case 
	// we'll also need to attach it to the node
	if (oldMeshSize != (unsigned int) meshes.size())	{

		rootOut->mNumMeshes = (unsigned int)meshes.size() - oldMeshSize;
		rootOut->mMeshes    = new unsigned int[rootOut->mNumMeshes];

		for (unsigned int a = 0; a  < rootOut->mNumMeshes;++a)	{
			rootOut->mMeshes[a] = oldMeshSize+a;
		}
	}

	// Setup the name of this node
	rootOut->mName.Set(root->name);

	// Now compute the final local transformation matrix of the
	// node from the given translation, rotation and scaling values.
	// (the rotation is given in Euler angles, XYZ order)
	//std::swap((float&)root->rotation.z,(float&)root->rotation.y);
	rootOut->mTransformation.FromEulerAnglesXYZ(AI_DEG_TO_RAD(root->rotation) );

	// apply scaling
	aiMatrix4x4& mat = rootOut->mTransformation;
	mat.a1 *= root->scaling.x;
	mat.b1 *= root->scaling.x; 
	mat.c1 *= root->scaling.x;
	mat.a2 *= root->scaling.y; 
	mat.b2 *= root->scaling.y; 
	mat.c2 *= root->scaling.y;
	mat.a3 *= root->scaling.z;
	mat.b3 *= root->scaling.z; 
	mat.c3 *= root->scaling.z;

	// apply translation
	mat.a4 += root->position.x; 
	mat.b4 += root->position.y; 
	mat.c4 += root->position.z;

	// now compute animations for the node
	ComputeAnimations(root,rootOut, anims);

	// Add all children recursively. First allocate enough storage
	// for them, then call us again
	rootOut->mNumChildren = (unsigned int)root->children.size();
	if (rootOut->mNumChildren)	{
		
		rootOut->mChildren = new aiNode*[rootOut->mNumChildren];
		for (unsigned int i = 0; i < rootOut->mNumChildren;++i)	{

			aiNode* node = rootOut->mChildren[i] =  new aiNode();
			node->mParent = rootOut;
			GenerateGraph(root->children[i],node,scene,batch,meshes,
				anims,attach,materials,defMatIdx);
		}
	}
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void IRRImporter::InternReadFile( const std::string& pFile, 
	aiScene* pScene, IOSystem* pIOHandler)
{
	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 IRR file " + pFile + "");

	// Construct the irrXML parser
	CIrrXML_IOStreamReader st(file.get());
	reader = createIrrXMLReader((IFileReadCallBack*) &st);

	// The root node of the scene
	Node* root = new Node(Node::DUMMY);
	root->parent = NULL;
	root->name = "<IRRSceneRoot>";

	// Current node parent
	Node* curParent = root;

	// Scenegraph node we're currently working on
	Node* curNode = NULL;

	// List of output cameras
	std::vector<aiCamera*> cameras;

	// List of output lights
	std::vector<aiLight*> lights;

	// Batch loader used to load external models
	BatchLoader batch(pIOHandler);
//	batch.SetBasePath(pFile);
	
	cameras.reserve(5);
	lights.reserve(5);

	bool inMaterials = false, inAnimator = false;
	unsigned int guessedAnimCnt = 0, guessedMeshCnt = 0, guessedMatCnt = 0;

	// Parse the XML file
	while (reader->read())	{
		switch (reader->getNodeType())	{
		case EXN_ELEMENT:
			
			if (!ASSIMP_stricmp(reader->getNodeName(),"node"))	{
				// ***********************************************************************
				/*  What we're going to do with the node depends
				 *  on its type:
				 *
				 *  "mesh" - Load a mesh from an external file
				 *  "cube" - Generate a cube 
				 *  "skybox" - Generate a skybox
				 *  "light" - A light source
				 *  "sphere" - Generate a sphere mesh
				 *  "animatedMesh" - Load an animated mesh from an external file
				 *    and join its animation channels with ours.
				 *  "empty" - A dummy node
				 *  "camera" - A camera
				 *  "terrain" - a terrain node (data comes from a heightmap)
				 *  "billboard", ""
				 *
				 *  Each of these nodes can be animated and all can have multiple
				 *  materials assigned (except lights, cameras and dummies, of course).
				 */
				// ***********************************************************************
				const char* sz = reader->getAttributeValueSafe("type");
				Node* nd;
				if (!ASSIMP_stricmp(sz,"mesh") || !ASSIMP_stricmp(sz,"octTree"))	{
					// OctTree's and meshes are treated equally
					nd = new Node(Node::MESH);
				}
				else if (!ASSIMP_stricmp(sz,"cube"))	{
					nd = new Node(Node::CUBE);
					++guessedMeshCnt;
					// meshes.push_back(StandardShapes::MakeMesh(&StandardShapes::MakeHexahedron));
				}
				else if (!ASSIMP_stricmp(sz,"skybox"))	{
					nd = new Node(Node::SKYBOX);
					guessedMeshCnt += 6;
				}
				else if (!ASSIMP_stricmp(sz,"camera"))	{
					nd = new Node(Node::CAMERA);

					// Setup a temporary name for the camera
					aiCamera* cam = new aiCamera();
					cam->mName.Set( nd->name );
					cameras.push_back(cam);
				}
				else if (!ASSIMP_stricmp(sz,"light"))	{
					nd = new Node(Node::LIGHT);

					// Setup a temporary name for the light
					aiLight* cam = new aiLight();
					cam->mName.Set( nd->name );
					lights.push_back(cam);
				}
				else if (!ASSIMP_stricmp(sz,"sphere"))	{
					nd = new Node(Node::SPHERE);
					++guessedMeshCnt;
				}
				else if (!ASSIMP_stricmp(sz,"animatedMesh"))	{
					nd = new Node(Node::ANIMMESH);
				}
				else if (!ASSIMP_stricmp(sz,"empty"))	{
					nd = new Node(Node::DUMMY);
				}
				else if (!ASSIMP_stricmp(sz,"terrain"))	{
					nd = new Node(Node::TERRAIN);
				}
				else if (!ASSIMP_stricmp(sz,"billBoard"))	{
					// We don't support billboards, so ignore them
					DefaultLogger::get()->error("IRR: Billboards are not supported by Assimp");
					nd = new Node(Node::DUMMY);
				}
				else	{
					DefaultLogger::get()->warn("IRR: Found unknown node: " + std::string(sz));

					/*  We skip the contents of nodes we don't know.
					 *  We parse the transformation and all animators 
					 *  and skip the rest.
					 */
					nd = new Node(Node::DUMMY);
				}

				/* Attach the newly created node to the scenegraph
				 */
				curNode = nd;
				nd->parent = curParent;
				curParent->children.push_back(nd);
			}
			else if (!ASSIMP_stricmp(reader->getNodeName(),"materials"))	{
				inMaterials = true;
			}
			else if (!ASSIMP_stricmp(reader->getNodeName(),"animators"))	{
				inAnimator = true;
			}
			else if (!ASSIMP_stricmp(reader->getNodeName(),"attributes"))	{
				/*  We should have a valid node here
				 *  FIX: no ... the scene root node is also contained in an attributes block
				 */
				if (!curNode)	{
#if 0
					DefaultLogger::get()->error("IRR: Encountered <attributes> element, but "
						"there is no node active");
#endif
					continue;
				}

				Animator* curAnim = NULL;

				// Materials can occur for nearly any type of node
				if (inMaterials && curNode->type != Node::DUMMY)	{
					/*  This is a material description - parse it!
					 */
					curNode->materials.push_back(std::pair< aiMaterial*, unsigned int > () );
					std::pair< aiMaterial*, unsigned int >& p = curNode->materials.back();

					p.first = ParseMaterial(p.second);

					++guessedMatCnt;
					continue;
				}
				else if (inAnimator)	{
					/*  This is an animation path - add a new animator
					 *  to the list.
					 */
					curNode->animators.push_back(Animator());
					curAnim = & curNode->animators.back();

					++guessedAnimCnt;
				}

				/*  Parse all elements in the attributes block 
				 *  and process them.
				 */
				while (reader->read())	{
					if (reader->getNodeType() == EXN_ELEMENT)	{
						if (!ASSIMP_stricmp(reader->getNodeName(),"vector3d"))	{
							VectorProperty prop;
							ReadVectorProperty(prop);

							if (inAnimator)	{
								if (curAnim->type == Animator::ROTATION && prop.name == "Rotation")	{
									// We store the rotation euler angles in 'direction'
									curAnim->direction = prop.value;
								}
								else if (curAnim->type == Animator::FOLLOW_SPLINE)	{
									// Check whether the vector follows the PointN naming scheme,
									// here N is the ONE-based index of the point
									if (prop.name.length() >= 6 && prop.name.substr(0,5) == "Point")	{
										// Add a new key to the list
										curAnim->splineKeys.push_back(aiVectorKey());
										aiVectorKey& key = curAnim->splineKeys.back();

										// and parse its properties
										key.mValue = prop.value;
										key.mTime  = strtoul10(&prop.name[5]);
									}
								}
								else if (curAnim->type == Animator::FLY_CIRCLE)	{
									if (prop.name == "Center")	{
										curAnim->circleCenter = prop.value;
									}
									else if (prop.name == "Direction")	{
										curAnim->direction = prop.value;

										// From Irrlicht's source - a workaround for backward compatibility with Irrlicht 1.1
										if (curAnim->direction == aiVector3D())	{
											curAnim->direction = aiVector3D(0.f,1.f,0.f);
										}
										else curAnim->direction.Normalize();
									}
								}
								else if (curAnim->type == Animator::FLY_STRAIGHT)	{
									if (prop.name == "Start")	{
										// We reuse the field here
										curAnim->circleCenter = prop.value;
									}
									else if (prop.name == "End")	{
										// We reuse the field here
										curAnim->direction = prop.value;
									}
								}
							}
							else	{
								if (prop.name == "Position")	{
									curNode->position = prop.value;
								}
								else if (prop.name == "Rotation")	{
									curNode->rotation = prop.value;
								}
								else if (prop.name == "Scale")	{
									curNode->scaling = prop.value;
								}
								else if (Node::CAMERA == curNode->type)
								{
									aiCamera* cam = cameras.back();
									if (prop.name == "Target")	{
										cam->mLookAt = prop.value;
									}
									else if (prop.name == "UpVector")	{
										cam->mUp = prop.value;
									}
								}
							}
						}
						else if (!ASSIMP_stricmp(reader->getNodeName(),"bool"))	{
							BoolProperty prop;
							ReadBoolProperty(prop);

							if (inAnimator && curAnim->type == Animator::FLY_CIRCLE && prop.name == "Loop")	{
								curAnim->loop = prop.value;
							}
						}
						else if (!ASSIMP_stricmp(reader->getNodeName(),"float"))	{
							FloatProperty prop;
							ReadFloatProperty(prop);

							if (inAnimator)	{
								// The speed property exists for several animators
								if (prop.name == "Speed")	{
									curAnim->speed = prop.value;
								}
								else if (curAnim->type == Animator::FLY_CIRCLE && prop.name == "Radius")	{
									curAnim->circleRadius = prop.value;
								}
								else if (curAnim->type == Animator::FOLLOW_SPLINE && prop.name == "Tightness")	{
									curAnim->tightness = prop.value;
								}
							}
							else	{
								if (prop.name == "FramesPerSecond" && Node::ANIMMESH == curNode->type)	{
									curNode->framesPerSecond = prop.value;
								}
								else if (Node::CAMERA == curNode->type)	{	
									/*  This is the vertical, not the horizontal FOV.
									*  We need to compute the right FOV from the
									*  screen aspect which we don't know yet.
									*/
									if (prop.name == "Fovy")	{
										cameras.back()->mHorizontalFOV  = prop.value;
									}
									else if (prop.name == "Aspect")	{
										cameras.back()->mAspect = prop.value;
									}
									else if (prop.name == "ZNear")	{
										cameras.back()->mClipPlaneNear = prop.value;
									}
									else if (prop.name == "ZFar")	{
										cameras.back()->mClipPlaneFar = prop.value;
									}
								}
								else if (Node::LIGHT == curNode->type)	{	
									/*  Additional light information
									 */
									if (prop.name == "Attenuation")	{
										lights.back()->mAttenuationLinear  = prop.value;
									}
									else if (prop.name == "OuterCone")	{
										lights.back()->mAngleOuterCone =  AI_DEG_TO_RAD( prop.value );
									}
									else if (prop.name == "InnerCone")	{
										lights.back()->mAngleInnerCone =  AI_DEG_TO_RAD( prop.value );
									}
								}
								// radius of the sphere to be generated -
								// or alternatively, size of the cube
								else if ((Node::SPHERE == curNode->type && prop.name == "Radius") 
									|| (Node::CUBE == curNode->type   && prop.name == "Size" ))	{
									
										curNode->sphereRadius = prop.value;
								}
							}
						}
						else if (!ASSIMP_stricmp(reader->getNodeName(),"int"))	{
							IntProperty prop;
							ReadIntProperty(prop);

							if (inAnimator)	{
								if (curAnim->type == Animator::FLY_STRAIGHT && prop.name == "TimeForWay")	{
									curAnim->timeForWay = prop.value;
								}
							}
							else	{
								// sphere polgon numbers in each direction
								if (Node::SPHERE == curNode->type)	{

									if (prop.name == "PolyCountX")	{
										curNode->spherePolyCountX = prop.value;
									}
									else if (prop.name == "PolyCountY")	{
										curNode->spherePolyCountY = prop.value;
									}
								}
							}
						}
						else if (!ASSIMP_stricmp(reader->getNodeName(),"string") ||!ASSIMP_stricmp(reader->getNodeName(),"enum"))	{
							StringProperty prop;
							ReadStringProperty(prop);
							if (prop.value.length())	{
								if (prop.name == "Name")	{
									curNode->name = prop.value;

									/*  If we're either a camera or a light source
									 *  we need to update the name in the aiLight/
									 *  aiCamera structure, too.
									 */
									if (Node::CAMERA == curNode->type)	{
										cameras.back()->mName.Set(prop.value);
									}
									else if (Node::LIGHT == curNode->type)	{
										lights.back()->mName.Set(prop.value);
									}
								}
								else if (Node::LIGHT == curNode->type && "LightType" == prop.name)
								{
									if (prop.value == "Spot")
										lights.back()->mType = aiLightSource_SPOT;
									else if (prop.value == "Point")
										lights.back()->mType = aiLightSource_POINT;
									else if (prop.value == "Directional")
										lights.back()->mType = aiLightSource_DIRECTIONAL;
									else
									{
										// We won't pass the validation with aiLightSourceType_UNDEFINED,
										// so we remove the light and replace it with a silly dummy node
										delete lights.back();
										lights.pop_back();
										curNode->type = Node::DUMMY;

										DefaultLogger::get()->error("Ignoring light of unknown type: " + prop.value);
									}
								}
								else if ((prop.name == "Mesh" && Node::MESH == curNode->type) ||
									Node::ANIMMESH == curNode->type)
								{
									/*  This is the file name of the mesh - either
									 *  animated or not. We need to make sure we setup
									 *  the correct postprocessing settings here.
									 */
									unsigned int pp = 0;
									BatchLoader::PropertyMap map;

									/* If the mesh is a static one remove all animations from the impor data
									 */
									if (Node::ANIMMESH != curNode->type)	{
										pp |= aiProcess_RemoveComponent;
										SetGenericProperty<int>(map.ints,AI_CONFIG_PP_RVC_FLAGS,
											aiComponent_ANIMATIONS | aiComponent_BONEWEIGHTS);
									}

									/*  TODO: maybe implement the protection against recursive
									*  loading calls directly in BatchLoader? The current
									*  implementation is not absolutely safe. A LWS and an IRR
									*  file referencing each other *could* cause the system to
									*  recurse forever.
									*/

									const std::string extension = GetExtension(prop.value);
									if ("irr" == extension)	{
										DefaultLogger::get()->error("IRR: Can't load another IRR file recursively");
									}
									else
									{
										curNode->id = batch.AddLoadRequest(prop.value,pp,&map);
										curNode->meshPath = prop.value;
									}
								}
								else if (inAnimator && prop.name == "Type")
								{
									// type of the animator
									if (prop.value == "rotation")	{
										curAnim->type = Animator::ROTATION;
									}
									else if (prop.value == "flyCircle")	{
										curAnim->type = Animator::FLY_CIRCLE;
									}
									else if (prop.value == "flyStraight")	{
										curAnim->type = Animator::FLY_CIRCLE;
									}
									else if (prop.value == "followSpline")	{
										curAnim->type = Animator::FOLLOW_SPLINE;
									}
									else	{
										DefaultLogger::get()->warn("IRR: Ignoring unknown animator: "
											+ prop.value);

										curAnim->type = Animator::UNKNOWN;
									}
								}
							}
						}
					}
					else if (reader->getNodeType() == EXN_ELEMENT_END && !ASSIMP_stricmp(reader->getNodeName(),"attributes"))	{
						break;
					}
				}
			}
			break;

		case EXN_ELEMENT_END:
		
			// If we reached the end of a node, we need to continue processing its parent
			if (!ASSIMP_stricmp(reader->getNodeName(),"node"))	{
				if (!curNode)	{
					// currently is no node set. We need to go
					// back in the node hierarchy
					if (!curParent)	{
						curParent = root;
						DefaultLogger::get()->error("IRR: Too many closing <node> elements");
					}
					else curParent = curParent->parent;
				}
				else curNode = NULL;
			}
			// clear all flags
			else if (!ASSIMP_stricmp(reader->getNodeName(),"materials"))	{
				inMaterials = false;
			}
			else if (!ASSIMP_stricmp(reader->getNodeName(),"animators"))	{
				inAnimator = false;
			}
			break;

		default:
			// GCC complains that not all enumeration values are handled
			break;
		}
	}

	/*  Now iterate through all cameras and compute their final (horizontal) FOV
	 */
	for (std::vector<aiCamera*>::iterator it = cameras.begin(), end = cameras.end();it != end; ++it)	{
		aiCamera* cam = *it;

		// screen aspect could be missing
		if (cam->mAspect)	{
			cam->mHorizontalFOV *= cam->mAspect;
		}
		else DefaultLogger::get()->warn("IRR: Camera aspect is not given, can't compute horizontal FOV");
	}

	batch.LoadAll();

	/* Allocate a tempoary scene data structure
	 */
	aiScene* tempScene = new aiScene();
	tempScene->mRootNode = new aiNode();
	tempScene->mRootNode->mName.Set("<IRRRoot>");

	/* Copy the cameras to the output array
	 */
	if (!cameras.empty())	{
		tempScene->mNumCameras = (unsigned int)cameras.size();
		tempScene->mCameras = new aiCamera*[tempScene->mNumCameras];
		::memcpy(tempScene->mCameras,&cameras[0],sizeof(void*)*tempScene->mNumCameras);
	}

	/* Copy the light sources to the output array
	 */
	if (!lights.empty())	{
		tempScene->mNumLights = (unsigned int)lights.size();
		tempScene->mLights = new aiLight*[tempScene->mNumLights];
		::memcpy(tempScene->mLights,&lights[0],sizeof(void*)*tempScene->mNumLights);
	}

	// temporary data
	std::vector< aiNodeAnim*>		anims;
	std::vector< aiMaterial*>		materials;
	std::vector< AttachmentInfo >	attach;
	std::vector<aiMesh*>			meshes;

	// try to guess how much storage we'll need
	anims.reserve     (guessedAnimCnt + (guessedAnimCnt >> 2));
	meshes.reserve    (guessedMeshCnt + (guessedMeshCnt >> 2));
	materials.reserve (guessedMatCnt  + (guessedMatCnt >> 2));

	/* Now process our scenegraph recursively: generate final
	 * meshes and generate animation channels for all nodes.
	 */
	unsigned int defMatIdx = UINT_MAX;
	GenerateGraph(root,tempScene->mRootNode, tempScene,
		batch, meshes, anims, attach, materials, defMatIdx);

	if (!anims.empty())
	{
		tempScene->mNumAnimations = 1;
		tempScene->mAnimations = new aiAnimation*[tempScene->mNumAnimations];
		aiAnimation* an = tempScene->mAnimations[0] = new aiAnimation();

		// ***********************************************************
		// This is only the global animation channel of the scene.
		// If there are animated models, they will have separate 
		// animation channels in the scene. To display IRR scenes
		// correctly, users will need to combine the global anim
		// channel with all the local animations they want to play
		// ***********************************************************
		an->mName.Set("Irr_GlobalAnimChannel");

		// copy all node animation channels to the global channel
		an->mNumChannels = (unsigned int)anims.size();
		an->mChannels = new aiNodeAnim*[an->mNumChannels];
		::memcpy(an->mChannels, & anims [0], sizeof(void*)*an->mNumChannels);
	}
	if (!meshes.empty())	{
		// copy all meshes to the temporary scene
		tempScene->mNumMeshes = (unsigned int)meshes.size();
		tempScene->mMeshes = new aiMesh*[tempScene->mNumMeshes];
		::memcpy(tempScene->mMeshes,&meshes[0],tempScene->mNumMeshes*
			sizeof(void*));
	}

	/* Copy all materials to the output array
	 */
	if (!materials.empty())	{
		tempScene->mNumMaterials = (unsigned int)materials.size();
		tempScene->mMaterials = new aiMaterial*[tempScene->mNumMaterials];
		::memcpy(tempScene->mMaterials,&materials[0],sizeof(void*)*
			tempScene->mNumMaterials);
	}

	/*  Now merge all sub scenes and attach them to the correct
	 *  attachment points in the scenegraph.
	 */
	SceneCombiner::MergeScenes(&pScene,tempScene,attach,
		AI_INT_MERGE_SCENE_GEN_UNIQUE_NAMES | (!configSpeedFlag ? (
		AI_INT_MERGE_SCENE_GEN_UNIQUE_NAMES_IF_NECESSARY | AI_INT_MERGE_SCENE_GEN_UNIQUE_MATNAMES) : 0));


	/*  If we have no meshes | no materials now set the INCOMPLETE
	 *  scene flag. This is necessary if we failed to load all
	 *  models from external files
	 */
	if (!pScene->mNumMeshes || !pScene->mNumMaterials)	{
		DefaultLogger::get()->warn("IRR: No meshes loaded, setting AI_SCENE_FLAGS_INCOMPLETE");
		pScene->mFlags |= AI_SCENE_FLAGS_INCOMPLETE;
	}

	/* Finished ... everything destructs automatically and all 
	 * temporary scenes have already been deleted by MergeScenes()
	 */
	return;
}