assimp/code/ValidateDataStructure.cpp

/*
---------------------------------------------------------------------------
Open Asset Import Library (assimp)
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/** @file  ValidateDataStructure.cpp
 *  @brief Implementation of the post processing step to validate 
 *    the data structure returned by Assimp.
 */

#include "AssimpPCH.h"

// internal headers
#include "ValidateDataStructure.h"
#include "BaseImporter.h"
#include "fast_atof.h"
#include "ProcessHelper.h"

// CRT headers
#include <stdarg.h>

using namespace Assimp;

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

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

// ------------------------------------------------------------------------------------------------
// Returns whether the processing step is present in the given flag field.
bool ValidateDSProcess::IsActive( unsigned int pFlags) const
{
	return (pFlags & aiProcess_ValidateDataStructure) != 0;
}
// ------------------------------------------------------------------------------------------------
AI_WONT_RETURN void ValidateDSProcess::ReportError(const char* msg,...)
{
	ai_assert(NULL != msg);

	va_list args;
	va_start(args,msg);

	char szBuffer[3000];
	const int iLen = vsprintf(szBuffer,msg,args);
	ai_assert(iLen > 0);

	va_end(args);
#ifdef _DEBUG
	ai_assert( false );
#endif
	throw DeadlyImportError("Validation failed: " + std::string(szBuffer,iLen));
}
// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::ReportWarning(const char* msg,...)
{
	ai_assert(NULL != msg);

	va_list args;
	va_start(args,msg);

	char szBuffer[3000];
	const int iLen = vsprintf(szBuffer,msg,args);
	ai_assert(iLen > 0);

	va_end(args);
	DefaultLogger::get()->warn("Validation warning: " + std::string(szBuffer,iLen));
}

// ------------------------------------------------------------------------------------------------
inline int HasNameMatch(const aiString& in, aiNode* node)
{
	int result = (node->mName == in ? 1 : 0 );
	for (unsigned int i = 0; i < node->mNumChildren;++i)	{
		result += HasNameMatch(in,node->mChildren[i]);
	}
	return result;
}

// ------------------------------------------------------------------------------------------------
template <typename T>
inline void ValidateDSProcess::DoValidation(T** parray, unsigned int size, 
	const char* firstName, const char* secondName)
{
	// validate all entries
	if (size)
	{
		if (!parray)
		{
			ReportError("aiScene::%s is NULL (aiScene::%s is %i)",
				firstName, secondName, size);
		}
		for (unsigned int i = 0; i < size;++i)
		{
			if (!parray[i])
			{
				ReportError("aiScene::%s[%i] is NULL (aiScene::%s is %i)",
					firstName,i,secondName,size);
			}
			Validate(parray[i]);
		}
	}
}

// ------------------------------------------------------------------------------------------------
template <typename T>
inline void ValidateDSProcess::DoValidationEx(T** parray, unsigned int size, 
	const char* firstName, const char* secondName)
{
	// validate all entries
	if (size)
	{
		if (!parray)	{
			ReportError("aiScene::%s is NULL (aiScene::%s is %i)",
				firstName, secondName, size);
		}
		for (unsigned int i = 0; i < size;++i)
		{
			if (!parray[i])
			{
				ReportError("aiScene::%s[%i] is NULL (aiScene::%s is %i)",
					firstName,i,secondName,size);
			}
			Validate(parray[i]);

			// check whether there are duplicate names
			for (unsigned int a = i+1; a < size;++a)
			{
				if (parray[i]->mName == parray[a]->mName)
				{
					this->ReportError("aiScene::%s[%i] has the same name as "
						"aiScene::%s[%i]",firstName, i,secondName, a);
				}
			}
		}
	}
}

// ------------------------------------------------------------------------------------------------
template <typename T>
inline void ValidateDSProcess::DoValidationWithNameCheck(T** array, 
	unsigned int size, const char* firstName, 
	const char* secondName)
{
	// validate all entries
	DoValidationEx(array,size,firstName,secondName);
	
	for (unsigned int i = 0; i < size;++i)
	{
		int res = HasNameMatch(array[i]->mName,mScene->mRootNode);
		if (!res)	{
			ReportError("aiScene::%s[%i] has no corresponding node in the scene graph (%s)",
				firstName,i,array[i]->mName.data);
		}
		else if (1 != res)	{
			ReportError("aiScene::%s[%i]: there are more than one nodes with %s as name",
				firstName,i,array[i]->mName.data);
		}
	}
}

// ------------------------------------------------------------------------------------------------
// Executes the post processing step on the given imported data.
void ValidateDSProcess::Execute( aiScene* pScene)
{
	this->mScene = pScene;
	DefaultLogger::get()->debug("ValidateDataStructureProcess begin");
	
	// validate the node graph of the scene
	Validate(pScene->mRootNode);
	
	// validate all meshes
	if (pScene->mNumMeshes) {
		DoValidation(pScene->mMeshes,pScene->mNumMeshes,"mMeshes","mNumMeshes");
	}
	else if (!(mScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))	{
		ReportError("aiScene::mNumMeshes is 0. At least one mesh must be there");
	}
	else if (pScene->mMeshes)	{
		ReportError("aiScene::mMeshes is non-null although there are no meshes");
	}
	
	// validate all animations
	if (pScene->mNumAnimations) {
		DoValidation(pScene->mAnimations,pScene->mNumAnimations,
			"mAnimations","mNumAnimations");
	}
	else if (pScene->mAnimations)	{
		ReportError("aiScene::mAnimations is non-null although there are no animations");
	}

	// validate all cameras
	if (pScene->mNumCameras) {
		DoValidationWithNameCheck(pScene->mCameras,pScene->mNumCameras,
			"mCameras","mNumCameras");
	}
	else if (pScene->mCameras)	{
		ReportError("aiScene::mCameras is non-null although there are no cameras");
	}

	// validate all lights
	if (pScene->mNumLights) {
		DoValidationWithNameCheck(pScene->mLights,pScene->mNumLights,
			"mLights","mNumLights");
	}
	else if (pScene->mLights)	{
		ReportError("aiScene::mLights is non-null although there are no lights");
	}

	// validate all textures
	if (pScene->mNumTextures) {
		DoValidation(pScene->mTextures,pScene->mNumTextures,
			"mTextures","mNumTextures");
	}
	else if (pScene->mTextures)	{
		ReportError("aiScene::mTextures is non-null although there are no textures");
	}
	
	// validate all materials
	if (pScene->mNumMaterials) {
		DoValidation(pScene->mMaterials,pScene->mNumMaterials,"mMaterials","mNumMaterials");
	}
#if 0
	// NOTE: ScenePreprocessor generates a default material if none is there
	else if (!(mScene->mFlags & AI_SCENE_FLAGS_INCOMPLETE))	{
		ReportError("aiScene::mNumMaterials is 0. At least one material must be there");
	}
#endif
	else if (pScene->mMaterials)	{
		ReportError("aiScene::mMaterials is non-null although there are no materials");
	}

//	if (!has)ReportError("The aiScene data structure is empty");
	DefaultLogger::get()->debug("ValidateDataStructureProcess end");
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiLight* pLight)
{
	if (pLight->mType == aiLightSource_UNDEFINED)
		ReportWarning("aiLight::mType is aiLightSource_UNDEFINED");

	if (!pLight->mAttenuationConstant &&
		!pLight->mAttenuationLinear   && 
		!pLight->mAttenuationQuadratic)	{
		ReportWarning("aiLight::mAttenuationXXX - all are zero");
	}

	if (pLight->mAngleInnerCone > pLight->mAngleOuterCone)
		ReportError("aiLight::mAngleInnerCone is larger than aiLight::mAngleOuterCone");

	if (pLight->mColorDiffuse.IsBlack() && pLight->mColorAmbient.IsBlack() 
		&& pLight->mColorSpecular.IsBlack())
	{
		ReportWarning("aiLight::mColorXXX - all are black and won't have any influence");
	}
}
	
// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiCamera* pCamera)
{
	if (pCamera->mClipPlaneFar <= pCamera->mClipPlaneNear)
		ReportError("aiCamera::mClipPlaneFar must be >= aiCamera::mClipPlaneNear");

	// FIX: there are many 3ds files with invalid FOVs. No reason to
	// reject them at all ... a warning is appropriate.
	if (!pCamera->mHorizontalFOV || pCamera->mHorizontalFOV >= (float)AI_MATH_PI)
		ReportWarning("%f is not a valid value for aiCamera::mHorizontalFOV",pCamera->mHorizontalFOV);
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiMesh* pMesh)
{
	// validate the material index of the mesh
	if (mScene->mNumMaterials && pMesh->mMaterialIndex >= mScene->mNumMaterials)
	{
		ReportError("aiMesh::mMaterialIndex is invalid (value: %i maximum: %i)",
			pMesh->mMaterialIndex,mScene->mNumMaterials-1);
	}

	Validate(&pMesh->mName);

	for (unsigned int i = 0; i < pMesh->mNumFaces; ++i)
	{
		aiFace& face = pMesh->mFaces[i];

		if (pMesh->mPrimitiveTypes)
		{
			switch (face.mNumIndices)
			{
			case 0:
				ReportError("aiMesh::mFaces[%i].mNumIndices is 0",i);
			case 1:
				if (0 == (pMesh->mPrimitiveTypes & aiPrimitiveType_POINT))
				{
					ReportError("aiMesh::mFaces[%i] is a POINT but aiMesh::mPrimtiveTypes "
						"does not report the POINT flag",i);
				}
				break;
			case 2:
				if (0 == (pMesh->mPrimitiveTypes & aiPrimitiveType_LINE))
				{
					ReportError("aiMesh::mFaces[%i] is a LINE but aiMesh::mPrimtiveTypes "
						"does not report the LINE flag",i);
				}
				break;
			case 3:
				if (0 == (pMesh->mPrimitiveTypes & aiPrimitiveType_TRIANGLE))
				{
					ReportError("aiMesh::mFaces[%i] is a TRIANGLE but aiMesh::mPrimtiveTypes "
						"does not report the TRIANGLE flag",i);
				}
				break;
			default:
				if (0 == (pMesh->mPrimitiveTypes & aiPrimitiveType_POLYGON))
				{
					this->ReportError("aiMesh::mFaces[%i] is a POLYGON but aiMesh::mPrimtiveTypes "
						"does not report the POLYGON flag",i);
				}
				break;
			};
		}

		if (!face.mIndices)
			ReportError("aiMesh::mFaces[%i].mIndices is NULL",i);
	}

	// positions must always be there ...
	if (!pMesh->mNumVertices || (!pMesh->mVertices && !mScene->mFlags))	{
		ReportError("The mesh contains no vertices");
	}

	if (pMesh->mNumVertices > AI_MAX_VERTICES) {
		ReportError("Mesh has too many vertices: %u, but the limit is %u",pMesh->mNumVertices,AI_MAX_VERTICES);
	}
	if (pMesh->mNumFaces > AI_MAX_FACES) {
		ReportError("Mesh has too many faces: %u, but the limit is %u",pMesh->mNumFaces,AI_MAX_FACES);
	}

	// if tangents are there there must also be bitangent vectors ...
	if ((pMesh->mTangents != NULL) != (pMesh->mBitangents != NULL))	{
		ReportError("If there are tangents, bitangent vectors must be present as well");
	}

	// faces, too
	if (!pMesh->mNumFaces || (!pMesh->mFaces && !mScene->mFlags))	{
		ReportError("Mesh contains no faces");
	}

	// now check whether the face indexing layout is correct:
	// unique vertices, pseudo-indexed.
	std::vector<bool> abRefList;
	abRefList.resize(pMesh->mNumVertices,false);
	for (unsigned int i = 0; i < pMesh->mNumFaces;++i)
	{
		aiFace& face = pMesh->mFaces[i];
		if (face.mNumIndices > AI_MAX_FACE_INDICES) {
			ReportError("Face %u has too many faces: %u, but the limit is %u",i,face.mNumIndices,AI_MAX_FACE_INDICES);
		}

		for (unsigned int a = 0; a < face.mNumIndices;++a)
		{
			if (face.mIndices[a] >= pMesh->mNumVertices)	{
				ReportError("aiMesh::mFaces[%i]::mIndices[%i] is out of range",i,a);
			}
			// the MSB flag is temporarily used by the extra verbose
			// mode to tell us that the JoinVerticesProcess might have 
			// been executed already.
			if ( !(this->mScene->mFlags & AI_SCENE_FLAGS_NON_VERBOSE_FORMAT ) && abRefList[face.mIndices[a]])
			{
				ReportError("aiMesh::mVertices[%i] is referenced twice - second "
					"time by aiMesh::mFaces[%i]::mIndices[%i]",face.mIndices[a],i,a);
			}
			abRefList[face.mIndices[a]] = true;
		}
	}

	// check whether there are vertices that aren't referenced by a face
	bool b = false;
	for (unsigned int i = 0; i < pMesh->mNumVertices;++i)	{
		if (!abRefList[i])b = true;
	}
	abRefList.clear();
	if (b)ReportWarning("There are unreferenced vertices");

	// texture channel 2 may not be set if channel 1 is zero ...
	{
		unsigned int i = 0;
		for (;i < AI_MAX_NUMBER_OF_TEXTURECOORDS;++i)
		{
			if (!pMesh->HasTextureCoords(i))break;
		}
		for (;i < AI_MAX_NUMBER_OF_TEXTURECOORDS;++i)
			if (pMesh->HasTextureCoords(i))
			{
				ReportError("Texture coordinate channel %i exists "
					"although the previous channel was NULL.",i);
			}
	}
	// the same for the vertex colors
	{
		unsigned int i = 0;
		for (;i < AI_MAX_NUMBER_OF_COLOR_SETS;++i)
		{
			if (!pMesh->HasVertexColors(i))break;
		}
		for (;i < AI_MAX_NUMBER_OF_COLOR_SETS;++i)
			if (pMesh->HasVertexColors(i))
			{
				ReportError("Vertex color channel %i is exists "
					"although the previous channel was NULL.",i);
			}
	}


	// now validate all bones
	if (pMesh->mNumBones)
	{
		if (!pMesh->mBones)
		{
			ReportError("aiMesh::mBones is NULL (aiMesh::mNumBones is %i)",
				pMesh->mNumBones);
		}
		boost::scoped_array<float> afSum(NULL);
		if (pMesh->mNumVertices)
		{
			afSum.reset(new float[pMesh->mNumVertices]);
			for (unsigned int i = 0; i < pMesh->mNumVertices;++i)
				afSum[i] = 0.0f;
		}

		// check whether there are duplicate bone names
		for (unsigned int i = 0; i < pMesh->mNumBones;++i)
		{
			const aiBone* bone = pMesh->mBones[i];
			if (bone->mNumWeights > AI_MAX_BONE_WEIGHTS) {
				ReportError("Bone %u has too many weights: %u, but the limit is %u",i,bone->mNumWeights,AI_MAX_BONE_WEIGHTS);
			}

			if (!pMesh->mBones[i])
			{
				ReportError("aiMesh::mBones[%i] is NULL (aiMesh::mNumBones is %i)",
					i,pMesh->mNumBones);
			}
			Validate(pMesh,pMesh->mBones[i],afSum.get());

			for (unsigned int a = i+1; a < pMesh->mNumBones;++a)
			{
				if (pMesh->mBones[i]->mName == pMesh->mBones[a]->mName)
				{
					ReportError("aiMesh::mBones[%i] has the same name as "
						"aiMesh::mBones[%i]",i,a);
				}
			}
		}
		// check whether all bone weights for a vertex sum to 1.0 ...
		for (unsigned int i = 0; i < pMesh->mNumVertices;++i)
		{
			if (afSum[i] && (afSum[i] <= 0.94 || afSum[i] >= 1.05))	{
				ReportWarning("aiMesh::mVertices[%i]: bone weight sum != 1.0 (sum is %f)",i,afSum[i]);
			}
		}
	}
	else if (pMesh->mBones)
	{
		ReportError("aiMesh::mBones is non-null although there are no bones");
	}
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiMesh* pMesh,
	const aiBone* pBone,float* afSum)
{
	this->Validate(&pBone->mName);

   	if (!pBone->mNumWeights)	{
		ReportError("aiBone::mNumWeights is zero");
	}

	// check whether all vertices affected by this bone are valid
	for (unsigned int i = 0; i < pBone->mNumWeights;++i)
	{
		if (pBone->mWeights[i].mVertexId >= pMesh->mNumVertices)	{
			ReportError("aiBone::mWeights[%i].mVertexId is out of range",i);
		}
		else if (!pBone->mWeights[i].mWeight || pBone->mWeights[i].mWeight > 1.0f)	{
			ReportWarning("aiBone::mWeights[%i].mWeight has an invalid value",i);
		}
		afSum[pBone->mWeights[i].mVertexId] += pBone->mWeights[i].mWeight;
	}
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiAnimation* pAnimation)
{
	Validate(&pAnimation->mName);

	// validate all materials
	if (pAnimation->mNumChannels)	
	{
		if (!pAnimation->mChannels)	{
			ReportError("aiAnimation::mChannels is NULL (aiAnimation::mNumChannels is %i)",
				pAnimation->mNumChannels);
		}
		for (unsigned int i = 0; i < pAnimation->mNumChannels;++i)
		{
			if (!pAnimation->mChannels[i])
			{
				ReportError("aiAnimation::mChannels[%i] is NULL (aiAnimation::mNumChannels is %i)",
					i, pAnimation->mNumChannels);
			}
			Validate(pAnimation, pAnimation->mChannels[i]);
		}
	}
	else ReportError("aiAnimation::mNumChannels is 0. At least one node animation channel must be there.");

	// Animation duration is allowed to be zero in cases where the anim contains only a single key frame.
	// if (!pAnimation->mDuration)this->ReportError("aiAnimation::mDuration is zero");
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::SearchForInvalidTextures(const aiMaterial* pMaterial,
	aiTextureType type)
{
	const char* szType = TextureTypeToString(type);

	// ****************************************************************************
	// Search all keys of the material ...
	// textures must be specified with ascending indices 
	// (e.g. diffuse #2 may not be specified if diffuse #1 is not there ...)
	// ****************************************************************************

	int iNumIndices = 0;
	int iIndex = -1;
	for (unsigned int i = 0; i < pMaterial->mNumProperties;++i)
	{
		aiMaterialProperty* prop = pMaterial->mProperties[i];
		if (!::strcmp(prop->mKey.data,"$tex.file") && prop->mSemantic == type)	{
			iIndex = std::max(iIndex, (int) prop->mIndex);
			++iNumIndices;

			if (aiPTI_String != prop->mType)
				ReportError("Material property %s is expected to be a string",prop->mKey.data);
		}
	}
	if (iIndex +1 != iNumIndices)	{
		ReportError("%s #%i is set, but there are only %i %s textures",
			szType,iIndex,iNumIndices,szType);
	}
	if (!iNumIndices)return;
	std::vector<aiTextureMapping> mappings(iNumIndices);

	// Now check whether all UV indices are valid ...
	bool bNoSpecified = true;
	for (unsigned int i = 0; i < pMaterial->mNumProperties;++i)
	{
		aiMaterialProperty* prop = pMaterial->mProperties[i];
		if (prop->mSemantic != type)continue;

		if ((int)prop->mIndex >= iNumIndices)
		{
			ReportError("Found texture property with index %i, although there "
				"are only %i textures of type %s",
				prop->mIndex, iNumIndices, szType);
		}
			
		if (!::strcmp(prop->mKey.data,"$tex.mapping"))	{
			if (aiPTI_Integer != prop->mType || prop->mDataLength < sizeof(aiTextureMapping))
			{
				ReportError("Material property %s%i is expected to be an integer (size is %i)",
					prop->mKey.data,prop->mIndex,prop->mDataLength);
			}
			mappings[prop->mIndex] = *((aiTextureMapping*)prop->mData);
		}
		else if (!::strcmp(prop->mKey.data,"$tex.uvtrafo"))	{
			if (aiPTI_Float != prop->mType || prop->mDataLength < sizeof(aiUVTransform))
			{
				ReportError("Material property %s%i is expected to be 5 floats large (size is %i)",
					prop->mKey.data,prop->mIndex, prop->mDataLength);
			}
			mappings[prop->mIndex] = *((aiTextureMapping*)prop->mData);
		}
		else if (!::strcmp(prop->mKey.data,"$tex.uvwsrc")) {
			if (aiPTI_Integer != prop->mType || sizeof(int) > prop->mDataLength)
			{
				ReportError("Material property %s%i is expected to be an integer (size is %i)",
					prop->mKey.data,prop->mIndex,prop->mDataLength);
			}
			bNoSpecified = false;

			// Ignore UV indices for texture channels that are not there ...

			// Get the value
			iIndex = *((unsigned int*)prop->mData);

			// Check whether there is a mesh using this material
			// which has not enough UV channels ...
			for (unsigned int a = 0; a < mScene->mNumMeshes;++a)
			{
				aiMesh* mesh = this->mScene->mMeshes[a];
				if(mesh->mMaterialIndex == (unsigned int)i)
				{
					int iChannels = 0;
					while (mesh->HasTextureCoords(iChannels))++iChannels;
					if (iIndex >= iChannels)
					{
						ReportWarning("Invalid UV index: %i (key %s). Mesh %i has only %i UV channels",
							iIndex,prop->mKey.data,a,iChannels);
					}
				}
			}
		}
	}
	if (bNoSpecified)
	{
		// Assume that all textures are using the first UV channel
		for (unsigned int a = 0; a < mScene->mNumMeshes;++a)
		{
			aiMesh* mesh = mScene->mMeshes[a];
			if(mesh->mMaterialIndex == (unsigned int)iIndex && mappings[0] == aiTextureMapping_UV)
			{
				if (!mesh->mTextureCoords[0])
				{
					// This is a special case ... it could be that the
					// original mesh format intended the use of a special
					// mapping here.
					ReportWarning("UV-mapped texture, but there are no UV coords");
				}
			}
		}
	}
}
// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiMaterial* pMaterial)
{
	// check whether there are material keys that are obviously not legal
	for (unsigned int i = 0; i < pMaterial->mNumProperties;++i)
	{
		const aiMaterialProperty* prop = pMaterial->mProperties[i];
		if (!prop)	{
			ReportError("aiMaterial::mProperties[%i] is NULL (aiMaterial::mNumProperties is %i)",
				i,pMaterial->mNumProperties);
		}
		if (!prop->mDataLength || !prop->mData)	{
			ReportError("aiMaterial::mProperties[%i].mDataLength or "
				"aiMaterial::mProperties[%i].mData is 0",i,i);
		}
		// check all predefined types
		if (aiPTI_String == prop->mType)	{
			// FIX: strings are now stored in a less expensive way, but we can't use the
			// validation routine for 'normal' aiStrings
			uint32_t len;
			if (prop->mDataLength < 5 || prop->mDataLength < 4 + (len=*reinterpret_cast<uint32_t*>(prop->mData)) + 1)	{
				ReportError("aiMaterial::mProperties[%i].mDataLength is "
					"too small to contain a string (%i, needed: %i)",
					i,prop->mDataLength,sizeof(aiString));
			}
			if(prop->mData[prop->mDataLength-1]) {
				ReportError("Missing null-terminator in string material property");
			}
		//	Validate((const aiString*)prop->mData);
		}
		else if (aiPTI_Float == prop->mType)	{
			if (prop->mDataLength < sizeof(float))	{
				ReportError("aiMaterial::mProperties[%i].mDataLength is "
					"too small to contain a float (%i, needed: %i)",
					i,prop->mDataLength,sizeof(float));
			}
		}
		else if (aiPTI_Integer == prop->mType)	{
			if (prop->mDataLength < sizeof(int))	{
				ReportError("aiMaterial::mProperties[%i].mDataLength is "
					"too small to contain an integer (%i, needed: %i)",
					i,prop->mDataLength,sizeof(int));
			}
		}
		// TODO: check whether there is a key with an unknown name ...
	}

	// make some more specific tests 
	float fTemp;
	int iShading;
	if (AI_SUCCESS == aiGetMaterialInteger( pMaterial,AI_MATKEY_SHADING_MODEL,&iShading))	{
		switch ((aiShadingMode)iShading)
		{
		case aiShadingMode_Blinn:
		case aiShadingMode_CookTorrance:
		case aiShadingMode_Phong:

			if (AI_SUCCESS != aiGetMaterialFloat(pMaterial,AI_MATKEY_SHININESS,&fTemp))	{
				ReportWarning("A specular shading model is specified but there is no "
					"AI_MATKEY_SHININESS key");
			}
			if (AI_SUCCESS == aiGetMaterialFloat(pMaterial,AI_MATKEY_SHININESS_STRENGTH,&fTemp) && !fTemp)	{
				ReportWarning("A specular shading model is specified but the value of the "
					"AI_MATKEY_SHININESS_STRENGTH key is 0.0");
			}
			break;
		default: ;
		};
	}

	if (AI_SUCCESS == aiGetMaterialFloat( pMaterial,AI_MATKEY_OPACITY,&fTemp) && (!fTemp || fTemp > 1.01f))	{
		ReportWarning("Invalid opacity value (must be 0 < opacity < 1.0)");
	}

	// Check whether there are invalid texture keys
	// TODO: that's a relict of the past, where texture type and index were baked
	// into the material string ... we could do that in one single pass.
	SearchForInvalidTextures(pMaterial,aiTextureType_DIFFUSE);
	SearchForInvalidTextures(pMaterial,aiTextureType_SPECULAR);
	SearchForInvalidTextures(pMaterial,aiTextureType_AMBIENT);
	SearchForInvalidTextures(pMaterial,aiTextureType_EMISSIVE);
	SearchForInvalidTextures(pMaterial,aiTextureType_OPACITY);
	SearchForInvalidTextures(pMaterial,aiTextureType_SHININESS);
	SearchForInvalidTextures(pMaterial,aiTextureType_HEIGHT);
	SearchForInvalidTextures(pMaterial,aiTextureType_NORMALS);
	SearchForInvalidTextures(pMaterial,aiTextureType_DISPLACEMENT);
	SearchForInvalidTextures(pMaterial,aiTextureType_LIGHTMAP);
	SearchForInvalidTextures(pMaterial,aiTextureType_REFLECTION);
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiTexture* pTexture)
{
	// the data section may NEVER be NULL
	if (!pTexture->pcData)	{
		ReportError("aiTexture::pcData is NULL");
	}
	if (pTexture->mHeight)
	{
		if (!pTexture->mWidth)ReportError("aiTexture::mWidth is zero "
			"(aiTexture::mHeight is %i, uncompressed texture)",pTexture->mHeight);
	}
	else 
	{
		if (!pTexture->mWidth) {
			ReportError("aiTexture::mWidth is zero (compressed texture)");
		}
		if ('\0' != pTexture->achFormatHint[3]) {
			ReportWarning("aiTexture::achFormatHint must be zero-terminated");
		}
		else if ('.'  == pTexture->achFormatHint[0])	{
			ReportWarning("aiTexture::achFormatHint should contain a file extension "
				"without a leading dot (format hint: %s).",pTexture->achFormatHint);
		}
	}

	const char* sz = pTexture->achFormatHint;
 	if ((sz[0] >= 'A' && sz[0] <= 'Z') ||
		(sz[1] >= 'A' && sz[1] <= 'Z') ||
		(sz[2] >= 'A' && sz[2] <= 'Z') ||
		(sz[3] >= 'A' && sz[3] <= 'Z'))	{
		ReportError("aiTexture::achFormatHint contains non-lowercase letters");
	}
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiAnimation* pAnimation,
	 const aiNodeAnim* pNodeAnim)
{
	Validate(&pNodeAnim->mNodeName);

	if (!pNodeAnim->mNumPositionKeys && !pNodeAnim->mScalingKeys && !pNodeAnim->mNumRotationKeys)
		ReportError("Empty node animation channel");

	// otherwise check whether one of the keys exceeds the total duration of the animation
	if (pNodeAnim->mNumPositionKeys)
	{
		if (!pNodeAnim->mPositionKeys)
		{
			this->ReportError("aiNodeAnim::mPositionKeys is NULL (aiNodeAnim::mNumPositionKeys is %i)",
				pNodeAnim->mNumPositionKeys);
		}
		double dLast = -10e10;
		for (unsigned int i = 0; i < pNodeAnim->mNumPositionKeys;++i)
		{
			// ScenePreprocessor will compute the duration if still the default value
			// (Aramis) Add small epsilon, comparison tended to fail if max_time == duration,
			//  seems to be due the compilers register usage/width.
			if (pAnimation->mDuration > 0. && pNodeAnim->mPositionKeys[i].mTime > pAnimation->mDuration+0.001)
			{
				ReportError("aiNodeAnim::mPositionKeys[%i].mTime (%.5f) is larger "
					"than aiAnimation::mDuration (which is %.5f)",i,
					(float)pNodeAnim->mPositionKeys[i].mTime,
					(float)pAnimation->mDuration);
			}
			if (i && pNodeAnim->mPositionKeys[i].mTime <= dLast)
			{
				ReportWarning("aiNodeAnim::mPositionKeys[%i].mTime (%.5f) is smaller "
					"than aiAnimation::mPositionKeys[%i] (which is %.5f)",i,
					(float)pNodeAnim->mPositionKeys[i].mTime,
					i-1, (float)dLast);
			}
			dLast = pNodeAnim->mPositionKeys[i].mTime;
		}
	}
	// rotation keys
	if (pNodeAnim->mNumRotationKeys)
	{
		if (!pNodeAnim->mRotationKeys)
		{
			this->ReportError("aiNodeAnim::mRotationKeys is NULL (aiNodeAnim::mNumRotationKeys is %i)",
				pNodeAnim->mNumRotationKeys);
		}
		double dLast = -10e10;
		for (unsigned int i = 0; i < pNodeAnim->mNumRotationKeys;++i)
		{
			if (pAnimation->mDuration > 0. && pNodeAnim->mRotationKeys[i].mTime > pAnimation->mDuration+0.001)
			{
				ReportError("aiNodeAnim::mRotationKeys[%i].mTime (%.5f) is larger "
					"than aiAnimation::mDuration (which is %.5f)",i,
					(float)pNodeAnim->mRotationKeys[i].mTime,
					(float)pAnimation->mDuration);
			}
			if (i && pNodeAnim->mRotationKeys[i].mTime <= dLast)
			{
				ReportWarning("aiNodeAnim::mRotationKeys[%i].mTime (%.5f) is smaller "
					"than aiAnimation::mRotationKeys[%i] (which is %.5f)",i,
					(float)pNodeAnim->mRotationKeys[i].mTime,
					i-1, (float)dLast);
			}
			dLast = pNodeAnim->mRotationKeys[i].mTime;
		}
	}
	// scaling keys
	if (pNodeAnim->mNumScalingKeys)
	{
		if (!pNodeAnim->mScalingKeys)	{
			ReportError("aiNodeAnim::mScalingKeys is NULL (aiNodeAnim::mNumScalingKeys is %i)",
				pNodeAnim->mNumScalingKeys);
		}
		double dLast = -10e10;
		for (unsigned int i = 0; i < pNodeAnim->mNumScalingKeys;++i)
		{
			if (pAnimation->mDuration > 0. && pNodeAnim->mScalingKeys[i].mTime > pAnimation->mDuration+0.001)
			{
				ReportError("aiNodeAnim::mScalingKeys[%i].mTime (%.5f) is larger "
					"than aiAnimation::mDuration (which is %.5f)",i,
					(float)pNodeAnim->mScalingKeys[i].mTime,
					(float)pAnimation->mDuration);
			}
			if (i && pNodeAnim->mScalingKeys[i].mTime <= dLast)
			{
				ReportWarning("aiNodeAnim::mScalingKeys[%i].mTime (%.5f) is smaller "
					"than aiAnimation::mScalingKeys[%i] (which is %.5f)",i,
					(float)pNodeAnim->mScalingKeys[i].mTime,
					i-1, (float)dLast);
			}
			dLast = pNodeAnim->mScalingKeys[i].mTime;
		}
	}

	if (!pNodeAnim->mNumScalingKeys && !pNodeAnim->mNumRotationKeys &&
		!pNodeAnim->mNumPositionKeys)
	{
		ReportError("A node animation channel must have at least one subtrack");
	}
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiNode* pNode)
{
	if (!pNode)ReportError("A node of the scenegraph is NULL");
	if (pNode != mScene->mRootNode && !pNode->mParent)
		this->ReportError("A node has no valid parent (aiNode::mParent is NULL)");

	this->Validate(&pNode->mName);

	// validate all meshes
	if (pNode->mNumMeshes)
	{
		if (!pNode->mMeshes)
		{
			ReportError("aiNode::mMeshes is NULL (aiNode::mNumMeshes is %i)",
				pNode->mNumMeshes);
		}
		std::vector<bool> abHadMesh;
		abHadMesh.resize(mScene->mNumMeshes,false);
		for (unsigned int i = 0; i < pNode->mNumMeshes;++i)
		{
			if (pNode->mMeshes[i] >= mScene->mNumMeshes)
			{
				ReportError("aiNode::mMeshes[%i] is out of range (maximum is %i)",
					pNode->mMeshes[i],mScene->mNumMeshes-1);
			}
			if (abHadMesh[pNode->mMeshes[i]])
			{
				ReportError("aiNode::mMeshes[%i] is already referenced by this node (value: %i)",
					i,pNode->mMeshes[i]);
			}
			abHadMesh[pNode->mMeshes[i]] = true;
		}
	}
	if (pNode->mNumChildren)
	{
		if (!pNode->mChildren)	{
			ReportError("aiNode::mChildren is NULL (aiNode::mNumChildren is %i)",
				pNode->mNumChildren);
		}
		for (unsigned int i = 0; i < pNode->mNumChildren;++i)	{
			Validate(pNode->mChildren[i]);
		}
	}
}

// ------------------------------------------------------------------------------------------------
void ValidateDSProcess::Validate( const aiString* pString)
{
	if (pString->length > MAXLEN)
	{
		this->ReportError("aiString::length is too large (%i, maximum is %i)",
			pString->length,MAXLEN);
	}
	const char* sz = pString->data;
	while (true)
	{
		if ('\0' == *sz)
		{
			if (pString->length != (unsigned int)(sz-pString->data))
				ReportError("aiString::data is invalid: the terminal zero is at a wrong offset");
			break;
		}
		else if (sz >= &pString->data[MAXLEN])
			ReportError("aiString::data is invalid. There is no terminal character");
		++sz;
	}
}