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DX11 C++ DX11 - Assimp - Mesh not Loading properly...

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Hi guys!


I've recently implemented Assimp with DirectX 11, now when I load a mesh with no submeshes, everything is fine. But when a mesh has submeshes, it pretty much get's a bad result.


Here's how I load my mesh using Assimp:



	Group<Group<MESH_STRUCT>> meshData;
	Group<Group<DWORD>> indices;

	Group<std::string> textures;




A function called GetData of the namespace AssimpIntegration:

FMESH_DATA AssimpIntegration::GetData(string &pFile, bool convLeftHanded, int maxSM)
	// Create an instance of the Importer class
	Assimp::Importer importer;
	// And have it read the given file with some example postprocessing
	// Usually - if speed is not the most important aspect for you - you'll 
	// propably to request more postprocessing than we do in this example.

	int cls = 0x0;
	if (convLeftHanded)
		cls = aiProcess_ConvertToLeftHanded;

	const aiScene* scene = importer.ReadFile( pFile, aiProcess_GenNormals | aiProcess_FindInstances | aiProcess_CalcTangentSpace | cls );
	// If the import failed, report it
	if (!scene)
		char* error = (char*)importer.GetErrorString();
		CE_ERROR(error, "Assimp Error");

	// Now we can access the file's contents. 
	Group<MESH_STRUCT> Vertices;
	Group<DWORD> indices;

	///////////////////////////////////PROCESS MESH///////////////////////////////////////////


	if (scene->HasAnimations())
		aiAnimation *anim = scene->mAnimations[0];

			aiVector3D position = anim->mChannels[0]->mPositionKeys[i].mValue;

			key.position = D3DXVECTOR3(position.x, position.y, position.z);


	D3DXVECTOR3 norms;
	float tanx, tany, tanz;
	float bitanx, bitany, bitanz;

	FOREACH (scene->mNumMeshes)
		if (i >= maxSM)

		aiMesh *mesh = scene->mMeshes[i];

		if (mesh->HasPositions())
			for (int v = 0; v != mesh->mNumVertices; v++)
				norms = D3DXVECTOR3(0,0,0);
				if (mesh->HasNormals())
					norms =  D3DXVECTOR3(mesh->mNormals[v].x,mesh->mNormals[v].y,mesh->mNormals[v].z);
				tanx = tany = tanz = 0;
				bitanx = bitany = bitanz = 0;

				if (mesh->HasTangentsAndBitangents())
					tanx = mesh->mTangents[v].x; tany = mesh->mTangents[v].y; tanz = mesh->mTangents[v].z;
					bitanx = mesh->mBitangents[v].x; bitany = mesh->mBitangents[v].y; bitanz = mesh->mBitangents[v].z;

					tanx, // TANGENTS

				if (mesh->HasTextureCoords(0))
					Vertices.back().U = mesh->mTextureCoords[0][v].x;
					Vertices.back().V = mesh->mTextureCoords[0][v].y;

			for (int f = 0; f != mesh->mNumFaces; f++)
				for (int index = 0; index != mesh->mFaces[f].mNumIndices; index++)


		// Set the required textures
		const aiMaterial* pMaterial = scene->mMaterials[mesh->mMaterialIndex];

		if (pMaterial->GetTextureCount(aiTextureType_DIFFUSE) > 0) {
			aiString Path;

			if (pMaterial->GetTexture(aiTextureType_DIFFUSE, 0, &Path, NULL, NULL, NULL, NULL, NULL) == AI_SUCCESS) {
				std::string FullPath = Path.data;

				if (FullPath.find("\\") != string::npos)
					FullPath = FullPath.substr(FullPath.find_last_of("\\")+1, FullPath.length() - (FullPath.length() - FullPath.find_last_of("\\")-1));
				else if (FullPath.find("/") != string::npos)
					FullPath = FullPath.substr(FullPath.find_last_of("//")+1, FullPath.length() - (FullPath.length() - FullPath.find_last_of("//")-1));

				string rFile = pFile;

				if (pFile.find("\\") != string::npos)
					rFile = pFile.substr(0, pFile.find_last_of("\\")+1);
					rFile = pFile.substr(0, pFile.find_last_of("/")+1);

				FullPath = rFile + FullPath;


	return data;



In my Mesh class:

// Get the buffer from assimp loader
	FMESH_DATA data = AssimpIntegration::GetData(filename, convLeftHanded, maxSM);
	fMeshData = data;

		fMeshData.Keys[i].position.x *= scalation.x;
		fMeshData.Keys[i].position.y *= scalation.y;
		fMeshData.Keys[i].position.z *= scalation.z;

	assimploadName = filename;

	vector<MESH_STRUCT> combinedVertices;

	for (int i = 0; i != data.meshData.size(); i++)
		if (i != NULL)

		// Prepare the data
		if (i == NULL) // Not an instance
			Vertices = new MESH_STRUCT[data.meshData[i].size()];
			Indices = new DWORD[data.indices[i].size()];

			Vertices = data.meshData[i].ToArray();
			Indices = data.indices[i].ToArray();
			SubMeshes.back().Vertices = new MESH_STRUCT[data.meshData[i].size()];
			SubMeshes.back().Indices = new DWORD[data.indices[i].size()];

			SubMeshes.back().Vertices = data.meshData[i].ToArray();
			SubMeshes.back().Indices = data.indices[i].ToArray();

		//combinedVertices.insert( combinedVertices.end(), data.meshData[i].group.begin(), data.meshData[i].group.end() );
		D3D11_BUFFER_DESC vertexBufferDesc, indexBufferDesc;
		D3D11_SUBRESOURCE_DATA vertexData, indexData;

		// Set up the description of the static vertex buffer.
		vertexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
		vertexBufferDesc.ByteWidth = sizeof(MESH_STRUCT) * data.meshData[i].size();
		vertexBufferDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
		vertexBufferDesc.CPUAccessFlags = 0;
		vertexBufferDesc.MiscFlags = 0;
		vertexBufferDesc.StructureByteStride = 0;

		// Give the subresource structure a pointer to the vertex data.
		if (i == NULL)
			vertexData.pSysMem = Vertices;
			vertexData.pSysMem = SubMeshes[SubMeshes.size()-1].Vertices;

		vertexData.SysMemPitch = 0;
		vertexData.SysMemSlicePitch = 0;

		if (i == NULL) // Not an instance
			dev->CreateBuffer(&vertexBufferDesc, &vertexData, &UMeshVBuffer);
			dev->CreateBuffer(&vertexBufferDesc, &vertexData, &SubMeshes.back().SMVBuffer);

		// Set up the description of the static index buffer.
		indexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
		indexBufferDesc.ByteWidth = sizeof(DWORD) * data.indices[i].size();
		indexBufferDesc.BindFlags = D3D11_BIND_INDEX_BUFFER;
		indexBufferDesc.CPUAccessFlags = 0;
		indexBufferDesc.MiscFlags = 0;
		indexBufferDesc.StructureByteStride = 0;

		// Give the subresource structure a pointer to the index data.
		if (i == NULL)
			indexData.pSysMem = Indices;
			indexData.pSysMem = SubMeshes[SubMeshes.size()-1].Indices;

		indexData.SysMemPitch = 0;
		indexData.SysMemSlicePitch = 0;

		if (i == NULL) // Not an instance
			dev->CreateBuffer(&indexBufferDesc, &indexData, &UMeshIBuffer);
			dev->CreateBuffer(&indexBufferDesc, &indexData, &SubMeshes.back().SMIBuffer);

		if (i != NULL)
			SubMeshes.back().passes.RecieveShadows = passes.RecieveShadows;
			SubMeshes.back().passes.CastShadows = passes.CastShadows;
			SubMeshes.back().passes.Diffuse = passes.Diffuse;
			SubMeshes.back().passes.Lighting = passes.Lighting;
			SubMeshes.back().passes.doubleSided = passes.doubleSided;
			SubMeshes.back().passes.texture_repeat = passes.texture_repeat;
			SubMeshes.back().passes.Wind = passes.Wind;
			SubMeshes.back().passes.GlobalMaterial.AmbientColor = passes.GlobalMaterial.AmbientColor;
		if (i == NULL) {
			IndexCount = data.indices[i].size();
			VertexCount = data.meshData[i].size();
	    } else {
			SubMeshes.back().indexCount = data.indices[i].size();
			SubMeshes.back().vertexCount = data.meshData[i].size();

		// Animations

		TextureHolder = new TextureObject[data.textures.size()];

		// PrepareTextures if any
			if (data.textures.size() == data.meshData.size())
				TextureHolder[i].CreateTexture(dev, data.textures[i].c_str());

				if (i == NULL) {
					passes.base = &TextureHolder[i]; 
					passes.Texture = true;}
				else {
					SubMeshes.back().passes.base = &TextureHolder[i]; 
					SubMeshes.back().passes.Texture = true;}




One example of a mesh with submeshes:




Look at the middle of the well...


Now what on earth is going on? blink.png

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Ok, it seems that I've fixed it.


I needed to pass aiProcess_Triangulate as an extra post processing flag to assimp!


But thanks for anyone thinking about this! wink.png

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