Assimp and D3D model loading: Mesh not being displayed in D3D
I would like to load models into D3D using Assimp. I would like to understand more how Assimp handles indices as I am having trouble getting it to work with obj models in a form
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I figured it out. While the above code is correct, I do not correct for the different subsets in a model. Here is my code to load up vertices from Assimp. If you want the full set of classes I use, please leave a note.
/**************************************************** **********File name: MeshLoader03.cpp**************** ******************************************************/ /*************Includes*****************************/ #include "stdafx.h" #include "MeshLoader03.h" /******************Class**************************/ bool MeshLoader03::LoadModel(const std::string& a_file, float a_scale, std::vector& indices, std::vector & mats) { //check if file exists std::ifstream fin(a_file.c_str()); if(!fin.fail()) { fin.close(); } else { MessageBox(NULL, TEXT("Couldn't open file: ") , TEXT("ERROR"), MB_OK | MB_ICONEXCLAMATION); return false; } //Assign scale m_scale = a_scale; //Assign mesh properties numVertices = 0; numSubsets = 0; numMaterials = 0; numTriangles = 0; //initialize success variable bool Ret = false; //Load mesh Ret = loadMesh(a_file,a_scale, vertices,indices,subsets,mats); //Return return Ret; } //Load mesh with Assimp bool MeshLoader03::loadMesh(const std::string& a_file, float a_scale, std::vector & indices, std::vector & mats) { //Assimp importer we are using Assimp::Importer importer; const aiScene* loadedScene = importer.ReadFile( a_file, aiProcessPreset_TargetRealtime_Quality | aiProcess_ConvertToLeftHanded ); //we have NO assimp object if(!loadedScene) { OutputDebugString(L"Model failed to load \n"); //OutputDebugString( (importer.GetErrorString()).c_str() ); return false; } else { //we have an assimp object with meshes if(loadedScene->HasMeshes()) { //Get mesh properties GetMeshProperties(loadedScene); //Extract Faces,Vertices,Subsets,Materials InitMaterials(a_file,loadedScene, numMaterials, mats); InitSubsetTable(a_file,loadedScene,numSubsets,subsets); InitVertices(a_file,loadedScene, numVertices, vertices); InitTriangles(a_file,loadedScene, numTriangles, indices); ScaleAsset(loadedScene); return true; } else //an assimp object with NO meshes return false; } } //Get mesh properties void MeshLoader03::GetMeshProperties(const aiScene* loadedScene) { //Get rootNode aiNode* rootNode = loadedScene->mRootNode; //Attributes numSubsets = loadedScene->mNumMeshes; numMaterials = loadedScene->mNumMaterials; //If only one node if(rootNode->mNumChildren == 0) { numVertices = loadedScene->mMeshes[0]->mNumVertices; numTriangles = loadedScene->mMeshes[0]->mNumFaces; } else { //For all the children for (size_t i =0 ;i mNumChildren; ++i) { //Get child node aiNode* childNode = rootNode->mChildren[i]; // Initialize the meshes in the scene one by one for (size_t n=0; n < childNode->mNumMeshes; ++n) { //get the mesh const aiMesh* paiMesh = loadedScene->mMeshes[childNode->mMeshes[n]]; //Update total vertices and faces numVertices+= paiMesh->mNumVertices; numTriangles+= paiMesh->mNumFaces; } } } } //Extract subsets void MeshLoader03::InitSubsetTable(const std::string& a_file,const aiScene* pScene, UINT numSubsets, std::vector mNumChildren; ++i) { //Get child node aiNode* childNode = rootNode->mChildren[i]; // Initialize the meshes in the scene one by one for (size_t n=0; n < childNode->mNumMeshes; ++n) { //get the mesh const aiMesh* paiMesh = pScene->mMeshes[childNode->mMeshes[n]]; subsets[subsetCounter].Id = pScene->mMeshes[childNode->mMeshes[n]]->mMaterialIndex; subsets[subsetCounter].VertexStart = vertexCounter; subsets[subsetCounter].VertexCount = paiMesh->mNumVertices; subsets[subsetCounter].FaceStart = faceCounter; subsets[subsetCounter].FaceCount = paiMesh->mNumFaces; //Update total vertices and faces vertexCounter+= paiMesh->mNumVertices; faceCounter+= paiMesh->mNumFaces; //Update counter subsetCounter++; } } } } //Extract Vertices void MeshLoader03::InitVertices(const std::string& a_file,const aiScene* pScene, UINT numVertices, std::vector mNumVertices;b++) { vertices[b].Pos.x = mesh->mVertices[b].x; vertices[b].Pos.y = mesh->mVertices[b].y; vertices[b].Pos.z = mesh->mVertices[b].z; if(mesh->HasVertexColors(0)) { const aiColor4D pColr = mesh->mColors[0][b]; vertices[b].Color.x = pColr.r; vertices[b].Color.y = pColr.g; vertices[b].Color.z = pColr.b; vertices[b].Color.w = pColr.a; } else vertices[b].Color = XMFLOAT4(1.0f,1.0f,0.0f,0.0f); } } else { //Counter vertexCounter = 0; //For all the children for (size_t i =0 ;i mNumChildren; ++i) { //Get child node aiNode* childNode = rootNode->mChildren[i]; // Initialize the meshes in the scene one by one for (size_t n=0; n < childNode->mNumMeshes; ++n) { //get the mesh const aiMesh* paiMesh = pScene->mMeshes[childNode->mMeshes[n]]; for(size_t b = 0;b mNumVertices;b++) { vertices[vertexCounter].Pos.x = paiMesh->mVertices[b].x; vertices[vertexCounter].Pos.y = paiMesh->mVertices[b].y; vertices[vertexCounter].Pos.z = paiMesh->mVertices[b].z; if(paiMesh->HasVertexColors(0)) { const aiColor4D pColr = paiMesh->mColors[0][i]; vertices[vertexCounter].Color.x = pColr.r; vertices[vertexCounter].Color.y = pColr.g; vertices[vertexCounter].Color.z = pColr.b; vertices[vertexCounter].Color.w = pColr.a; } else vertices[vertexCounter].Color = XMFLOAT4(1.0f,1.0f,0.0f,0.0f); vertexCounter++; } } } } } //Extract Triangles void MeshLoader03::InitTriangles(const std::string& a_file,const aiScene* pScene, UINT numTriangles, std::vector & indices) { //indices.resize(numTriangles*3); //Get rootNode aiNode* rootNode = pScene->mRootNode; //Counter for vertices and indices unsigned int indexCounter, indexStart; indexCounter = 0; indexStart = indexCounter; //If only one node if(rootNode->mNumChildren == 0) { const aiMesh* mesh = pScene->mMeshes[0]; for(size_t b = 0;b mNumFaces;b++) { indices[indexCounter++] = mesh->mFaces[b].mIndices[0] + indexStart; indices[indexCounter++] = mesh->mFaces[b].mIndices[1] + indexStart; indices[indexCounter++] = mesh->mFaces[b].mIndices[2] + indexStart; } } else { //Counter indexStart = 0; indexCounter = 0; //For all the children for (size_t i =0 ;i mNumChildren; ++i) { //Get child node aiNode* childNode = rootNode->mChildren[i]; // Initialize the meshes in the scene one by one for (size_t n=0; n < childNode->mNumMeshes; ++n) { //get the mesh const aiMesh* mesh = pScene->mMeshes[childNode->mMeshes[n]]; for(size_t b = 0;b mNumFaces;b++) { //indices[indexCounter++] = mesh->mFaces[b].mIndices[0] + indexStart; //indices[indexCounter++] = mesh->mFaces[b].mIndices[1] + indexStart; //indices[indexCounter++] = mesh->mFaces[b].mIndices[2] + indexStart; indices.push_back(mesh->mFaces[b].mIndices[0] + indexStart); indices.push_back(mesh->mFaces[b].mIndices[1] + indexStart); indices.push_back(mesh->mFaces[b].mIndices[2] + indexStart); } indexStart += mesh->mNumVertices; } } } } /*********************Conversion functions**********************************/ //AiVector3 to XMFLOAT3 XMFLOAT3 MeshLoader03::aiVec3ToXMFloat3(const aiVector3D* vector) { //Ooutput XMFLOAT3 output; //Assignmetns output.x = vector->x; output.y = vector->y; output.z = vector->z; //Send back result return output; } //AiColor to XMFLOAT4 XMFLOAT4 MeshLoader03::aiColorToXMFLOAT4(const aiColor4D* color) { //Ooutput XMFLOAT4 output; //Assignmetns output.x = color->r; output.y = color->g; output.z = color->b; output.w = color->a; //Send back result return output; } //AiMatrix to XMFLOAT4X4 XMFLOAT4X4 MeshLoader03::aiMatrixToXMFloat4x4(const aiMatrix4x4* aiMe) { XMFLOAT4X4 output; output._11 = aiMe->a1; output._12 = aiMe->a2; output._13 = aiMe->a3; output._14 = aiMe->a4; output._21 = aiMe->b1; output._22 = aiMe->b2; output._23 = aiMe->b3; output._24 = aiMe->b4; output._31 = aiMe->c1; output._32 = aiMe->c2; output._33 = aiMe->c3; output._34 = aiMe->c4; output._41 = aiMe->d1; output._42 = aiMe->d2; output._43 = aiMe->d3; output._44 = aiMe->d4; return output; } /****************Scaling Functions: Taken from Assimp**********************/ //------------------------------------------------------------------------------- // Calculate the boundaries of a given node and all of its children // The boundaries are in Worldspace (AABB) // piNode Input node // p_avOut Receives the min/max boundaries. Must point to 2 vec3s // piMatrix Transformation matrix of the graph at this position //------------------------------------------------------------------------------- int MeshLoader03::CalculateBounds(aiNode* piNode, aiVector3D* p_avOut, const aiMatrix4x4& piMatrix, const aiScene* pcScene) { assert(NULL != piNode); assert(NULL != p_avOut); aiMatrix4x4 mTemp = piNode->mTransformation; mTemp.Transpose(); const aiMatrix4x4 aiMe = mTemp * piMatrix; for (unsigned int i = 0; i < piNode->mNumMeshes;++i) { for( unsigned int a = 0; a < pcScene->mMeshes[piNode->mMeshes[i]]->mNumVertices;++a) { const aiVector3D pc = pcScene->mMeshes[piNode->mMeshes[i]]->mVertices[a]; XMFLOAT3 pc11 = aiVec3ToXMFloat3(&pc); XMFLOAT4X4 aiMe1 = aiMatrixToXMFloat4x4(&aiMe); XMVECTOR pc1 = XMVector3TransformCoord(XMLoadFloat3(&pc11),XMLoadFloat4x4(&aiMe1)); p_avOut[0].x = min( p_avOut[0].x, pc1.m128_f32[0]); p_avOut[0].y = min( p_avOut[0].y, pc1.m128_f32[1]); p_avOut[0].z = min( p_avOut[0].z, pc1.m128_f32[2]); p_avOut[1].x = max( p_avOut[1].x, pc1.m128_f32[0]); p_avOut[1].y = max( p_avOut[1].y, pc1.m128_f32[1]); p_avOut[1].z = max( p_avOut[1].z, pc1.m128_f32[2]); } } for (unsigned int i = 0; i < piNode->mNumChildren;++i) { CalculateBounds( piNode->mChildren[i], p_avOut, aiMe, pcScene); } return 1; } //------------------------------------------------------------------------------- // Scale the asset that it fits perfectly into the viewer window // The function calculates the boundaries of the mesh and modifies the // global world transformation matrix according to the aset AABB //------------------------------------------------------------------------------- int MeshLoader03::ScaleAsset(const aiScene* pcScene) { aiVector3D aiVecs[2] = { aiVector3D( 1e10f, 1e10f, 1e10f), aiVector3D( -1e10f, -1e10f, -1e10f) }; if (pcScene->mRootNode) { aiMatrix4x4 m; CalculateBounds(pcScene->mRootNode,aiVecs,m, pcScene); } aiVector3D vDelta = aiVecs[1] - aiVecs[0]; aiVector3D vHalf = aiVecs[0] + (vDelta / 2.0f); float fScale = 10.0f / vDelta.Length(); aiMatrix4x4 g_mWorld = aiMatrix4x4( 1.0f,0.0f,0.0f,0.0f, 0.0f,1.0f,0.0f,0.0f, 0.0f,0.0f,1.0f,0.0f, -vHalf.x,-vHalf.y,-vHalf.z,1.0f) * aiMatrix4x4( fScale*m_scale,0.0f,0.0f,0.0f, 0.0f,fScale*m_scale,0.0f,0.0f, 0.0f,0.0f,fScale*m_scale,0.0f, 0.0f,0.0f,0.0f,1.0f); m_World = aiMatrixToXMFloat4x4(&g_mWorld); return 1; } 讨论(0)
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