/* Open Asset Import Library (assimp) ---------------------------------------------------------------------- Copyright (c) 2006-2020, assimp team All rights reserved. Redistribution and use of this software in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * 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 following disclaimer in the documentation and/or other materials provided with the distribution. * Neither the name of the assimp team, nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission of the assimp team. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ---------------------------------------------------------------------- */ /** * @file Implementation of the SplitLargeMeshes postprocessing step */ // internal headers of the post-processing framework #include "SplitLargeMeshes.h" #include "ProcessHelper.h" using namespace Assimp; // ------------------------------------------------------------------------------------------------ SplitLargeMeshesProcess_Triangle::SplitLargeMeshesProcess_Triangle() { LIMIT = AI_SLM_DEFAULT_MAX_TRIANGLES; } // ------------------------------------------------------------------------------------------------ SplitLargeMeshesProcess_Triangle::~SplitLargeMeshesProcess_Triangle() { // nothing to do here } // ------------------------------------------------------------------------------------------------ // Returns whether the processing step is present in the given flag field. bool SplitLargeMeshesProcess_Triangle::IsActive( unsigned int pFlags) const { return (pFlags & aiProcess_SplitLargeMeshes) != 0; } // ------------------------------------------------------------------------------------------------ // Executes the post processing step on the given imported data. void SplitLargeMeshesProcess_Triangle::Execute( aiScene* pScene) { if (0xffffffff == this->LIMIT || nullptr == pScene ) { return; } ASSIMP_LOG_DEBUG("SplitLargeMeshesProcess_Triangle begin"); std::vector > avList; for( unsigned int a = 0; a < pScene->mNumMeshes; ++a) { this->SplitMesh(a, pScene->mMeshes[a],avList); } if (avList.size() != pScene->mNumMeshes) { // it seems something has been split. rebuild the mesh list delete[] pScene->mMeshes; pScene->mNumMeshes = (unsigned int)avList.size(); pScene->mMeshes = new aiMesh*[avList.size()]; for (unsigned int i = 0; i < avList.size();++i) { pScene->mMeshes[i] = avList[i].first; } // now we need to update all nodes this->UpdateNode(pScene->mRootNode,avList); ASSIMP_LOG_INFO("SplitLargeMeshesProcess_Triangle finished. Meshes have been split"); } else { ASSIMP_LOG_DEBUG("SplitLargeMeshesProcess_Triangle finished. There was nothing to do"); } } // ------------------------------------------------------------------------------------------------ // Setup properties void SplitLargeMeshesProcess_Triangle::SetupProperties( const Importer* pImp) { // get the current value of the split property this->LIMIT = pImp->GetPropertyInteger(AI_CONFIG_PP_SLM_TRIANGLE_LIMIT,AI_SLM_DEFAULT_MAX_TRIANGLES); } // ------------------------------------------------------------------------------------------------ // Update a node after some meshes have been split void SplitLargeMeshesProcess_Triangle::UpdateNode(aiNode* pcNode, const std::vector >& avList) { // for every index in out list build a new entry std::vector aiEntries; aiEntries.reserve(pcNode->mNumMeshes + 1); for (unsigned int i = 0; i < pcNode->mNumMeshes;++i) { for (unsigned int a = 0; a < avList.size();++a) { if (avList[a].second == pcNode->mMeshes[i]) { aiEntries.push_back(a); } } } // now build the new list delete[] pcNode->mMeshes; pcNode->mNumMeshes = (unsigned int)aiEntries.size(); pcNode->mMeshes = new unsigned int[pcNode->mNumMeshes]; for (unsigned int b = 0; b < pcNode->mNumMeshes;++b) { pcNode->mMeshes[b] = aiEntries[b]; } // recusively update all other nodes for (unsigned int i = 0; i < pcNode->mNumChildren;++i) { UpdateNode ( pcNode->mChildren[i], avList ); } } // ------------------------------------------------------------------------------------------------ // Executes the post processing step on the given imported data. void SplitLargeMeshesProcess_Triangle::SplitMesh( unsigned int a, aiMesh* pMesh, std::vector >& avList) { if (pMesh->mNumFaces > SplitLargeMeshesProcess_Triangle::LIMIT) { ASSIMP_LOG_INFO("Mesh exceeds the triangle limit. It will be split ..."); // we need to split this mesh into sub meshes // determine the size of a submesh const unsigned int iSubMeshes = (pMesh->mNumFaces / LIMIT) + 1; const unsigned int iOutFaceNum = pMesh->mNumFaces / iSubMeshes; const unsigned int iOutVertexNum = iOutFaceNum * 3; // now generate all submeshes for (unsigned int i = 0; i < iSubMeshes;++i) { aiMesh* pcMesh = new aiMesh; pcMesh->mNumFaces = iOutFaceNum; pcMesh->mMaterialIndex = pMesh->mMaterialIndex; // the name carries the adjacency information between the meshes pcMesh->mName = pMesh->mName; if (i == iSubMeshes-1) { pcMesh->mNumFaces = iOutFaceNum + ( pMesh->mNumFaces - iOutFaceNum * iSubMeshes); } // copy the list of faces pcMesh->mFaces = new aiFace[pcMesh->mNumFaces]; const unsigned int iBase = iOutFaceNum * i; // get the total number of indices unsigned int iCnt = 0; for (unsigned int p = iBase; p < pcMesh->mNumFaces + iBase;++p) { iCnt += pMesh->mFaces[p].mNumIndices; } pcMesh->mNumVertices = iCnt; // allocate storage if (pMesh->mVertices != nullptr) { pcMesh->mVertices = new aiVector3D[iCnt]; } if (pMesh->HasNormals()) { pcMesh->mNormals = new aiVector3D[iCnt]; } if (pMesh->HasTangentsAndBitangents()) { pcMesh->mTangents = new aiVector3D[iCnt]; pcMesh->mBitangents = new aiVector3D[iCnt]; } // texture coordinates for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS;++c) { pcMesh->mNumUVComponents[c] = pMesh->mNumUVComponents[c]; if (pMesh->HasTextureCoords( c)) { pcMesh->mTextureCoords[c] = new aiVector3D[iCnt]; } } // vertex colors for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS;++c) { if (pMesh->HasVertexColors( c)) { pcMesh->mColors[c] = new aiColor4D[iCnt]; } } if (pMesh->HasBones()) { // assume the number of bones won't change in most cases pcMesh->mBones = new aiBone*[pMesh->mNumBones]; // iterate through all bones of the mesh and find those which // need to be copied to the split mesh std::vector avTempWeights; for (unsigned int p = 0; p < pcMesh->mNumBones;++p) { aiBone* const bone = pcMesh->mBones[p]; avTempWeights.clear(); avTempWeights.reserve(bone->mNumWeights / iSubMeshes); for (unsigned int q = 0; q < bone->mNumWeights;++q) { aiVertexWeight& weight = bone->mWeights[q]; if(weight.mVertexId >= iBase && weight.mVertexId < iBase + iOutVertexNum) { avTempWeights.push_back(weight); weight = avTempWeights.back(); weight.mVertexId -= iBase; } } if (!avTempWeights.empty()) { // we'll need this bone. Copy it ... aiBone* pc = new aiBone(); pcMesh->mBones[pcMesh->mNumBones++] = pc; pc->mName = aiString(bone->mName); pc->mNumWeights = (unsigned int)avTempWeights.size(); pc->mOffsetMatrix = bone->mOffsetMatrix; // no need to reallocate the array for the last submesh. // Here we can reuse the (large) source array, although // we'll waste some memory if (iSubMeshes-1 == i) { pc->mWeights = bone->mWeights; bone->mWeights = nullptr; } else { pc->mWeights = new aiVertexWeight[pc->mNumWeights]; } // copy the weights ::memcpy(pc->mWeights,&avTempWeights[0],sizeof(aiVertexWeight)*pc->mNumWeights); } } } // (we will also need to copy the array of indices) unsigned int iCurrent = 0; for (unsigned int p = 0; p < pcMesh->mNumFaces;++p) { pcMesh->mFaces[p].mNumIndices = 3; // allocate a new array const unsigned int iTemp = p + iBase; const unsigned int iNumIndices = pMesh->mFaces[iTemp].mNumIndices; // setup face type and number of indices pcMesh->mFaces[p].mNumIndices = iNumIndices; unsigned int* pi = pMesh->mFaces[iTemp].mIndices; unsigned int* piOut = pcMesh->mFaces[p].mIndices = new unsigned int[iNumIndices]; // need to update the output primitive types switch (iNumIndices) { case 1: pcMesh->mPrimitiveTypes |= aiPrimitiveType_POINT; break; case 2: pcMesh->mPrimitiveTypes |= aiPrimitiveType_LINE; break; case 3: pcMesh->mPrimitiveTypes |= aiPrimitiveType_TRIANGLE; break; default: pcMesh->mPrimitiveTypes |= aiPrimitiveType_POLYGON; } // and copy the contents of the old array, offset by current base for (unsigned int v = 0; v < iNumIndices;++v) { unsigned int iIndex = pi[v]; unsigned int iIndexOut = iCurrent++; piOut[v] = iIndexOut; // copy positions if (pMesh->mVertices != nullptr) { pcMesh->mVertices[iIndexOut] = pMesh->mVertices[iIndex]; } // copy normals if (pMesh->HasNormals()) { pcMesh->mNormals[iIndexOut] = pMesh->mNormals[iIndex]; } // copy tangents/bitangents if (pMesh->HasTangentsAndBitangents()) { pcMesh->mTangents[iIndexOut] = pMesh->mTangents[iIndex]; pcMesh->mBitangents[iIndexOut] = pMesh->mBitangents[iIndex]; } // texture coordinates for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS;++c) { if (pMesh->HasTextureCoords( c ) ) { pcMesh->mTextureCoords[c][iIndexOut] = pMesh->mTextureCoords[c][iIndex]; } } // vertex colors for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS;++c) { if (pMesh->HasVertexColors( c)) { pcMesh->mColors[c][iIndexOut] = pMesh->mColors[c][iIndex]; } } } } // add the newly created mesh to the list avList.emplace_back(pcMesh,a); } // now delete the old mesh data delete pMesh; } else { avList.emplace_back(pMesh,a); } } // ------------------------------------------------------------------------------------------------ SplitLargeMeshesProcess_Vertex::SplitLargeMeshesProcess_Vertex() { LIMIT = AI_SLM_DEFAULT_MAX_VERTICES; } // ------------------------------------------------------------------------------------------------ SplitLargeMeshesProcess_Vertex::~SplitLargeMeshesProcess_Vertex() { // nothing to do here } // ------------------------------------------------------------------------------------------------ // Returns whether the processing step is present in the given flag field. bool SplitLargeMeshesProcess_Vertex::IsActive( unsigned int pFlags) const { return (pFlags & aiProcess_SplitLargeMeshes) != 0; } // ------------------------------------------------------------------------------------------------ // Executes the post processing step on the given imported data. void SplitLargeMeshesProcess_Vertex::Execute( aiScene* pScene) { if (0xffffffff == this->LIMIT || nullptr == pScene ) { return; } ASSIMP_LOG_DEBUG("SplitLargeMeshesProcess_Vertex begin"); std::vector > avList; //Check for point cloud first, //Do not process point cloud, splitMesh works only with faces data for (unsigned int a = 0; a < pScene->mNumMeshes; a++) { if ( pScene->mMeshes[a]->mPrimitiveTypes == aiPrimitiveType_POINT ) { return; } } for( unsigned int a = 0; a < pScene->mNumMeshes; ++a ) { this->SplitMesh(a, pScene->mMeshes[a], avList); } if (avList.size() != pScene->mNumMeshes) { // it seems something has been split. rebuild the mesh list delete[] pScene->mMeshes; pScene->mNumMeshes = (unsigned int)avList.size(); pScene->mMeshes = new aiMesh*[avList.size()]; for (unsigned int i = 0; i < avList.size();++i) { pScene->mMeshes[i] = avList[i].first; } // now we need to update all nodes SplitLargeMeshesProcess_Triangle::UpdateNode(pScene->mRootNode,avList); ASSIMP_LOG_INFO("SplitLargeMeshesProcess_Vertex finished. Meshes have been split"); } else { ASSIMP_LOG_DEBUG("SplitLargeMeshesProcess_Vertex finished. There was nothing to do"); } } // ------------------------------------------------------------------------------------------------ // Setup properties void SplitLargeMeshesProcess_Vertex::SetupProperties( const Importer* pImp) { this->LIMIT = pImp->GetPropertyInteger(AI_CONFIG_PP_SLM_VERTEX_LIMIT,AI_SLM_DEFAULT_MAX_VERTICES); } // ------------------------------------------------------------------------------------------------ // Executes the post processing step on the given imported data. void SplitLargeMeshesProcess_Vertex::SplitMesh( unsigned int a, aiMesh* pMesh, std::vector >& avList) { if (pMesh->mNumVertices > SplitLargeMeshesProcess_Vertex::LIMIT) { typedef std::vector< std::pair > VertexWeightTable; // build a per-vertex weight list if necessary VertexWeightTable* avPerVertexWeights = ComputeVertexBoneWeightTable(pMesh); // we need to split this mesh into sub meshes // determine the estimated size of a submesh // (this could be too large. Max waste is a single digit percentage) const unsigned int iSubMeshes = (pMesh->mNumVertices / SplitLargeMeshesProcess_Vertex::LIMIT) + 1; // create a std::vector to indicate which vertices // have already been copied std::vector avWasCopied; avWasCopied.resize(pMesh->mNumVertices,0xFFFFFFFF); // try to find a good estimate for the number of output faces // per mesh. Add 12.5% as buffer unsigned int iEstimatedSize = pMesh->mNumFaces / iSubMeshes; iEstimatedSize += iEstimatedSize >> 3; // now generate all submeshes unsigned int iBase( 0 ); while (true) { const unsigned int iOutVertexNum = SplitLargeMeshesProcess_Vertex::LIMIT; aiMesh* pcMesh = new aiMesh; pcMesh->mNumVertices = 0; pcMesh->mMaterialIndex = pMesh->mMaterialIndex; // the name carries the adjacency information between the meshes pcMesh->mName = pMesh->mName; typedef std::vector BoneWeightList; if (pMesh->HasBones()) { pcMesh->mBones = new aiBone*[pMesh->mNumBones]; ::memset(pcMesh->mBones,0,sizeof(void*)*pMesh->mNumBones); } // clear the temporary helper array if (iBase) { // we can't use memset here we unsigned int needn' be 32 bits for (auto &elem : avWasCopied) { elem = 0xffffffff; } } // output vectors std::vector vFaces; // reserve enough storage for most cases if (pMesh->HasPositions()) { pcMesh->mVertices = new aiVector3D[iOutVertexNum]; } if (pMesh->HasNormals()) { pcMesh->mNormals = new aiVector3D[iOutVertexNum]; } if (pMesh->HasTangentsAndBitangents()) { pcMesh->mTangents = new aiVector3D[iOutVertexNum]; pcMesh->mBitangents = new aiVector3D[iOutVertexNum]; } for (unsigned int c = 0; pMesh->HasVertexColors(c);++c) { pcMesh->mColors[c] = new aiColor4D[iOutVertexNum]; } for (unsigned int c = 0; pMesh->HasTextureCoords(c);++c) { pcMesh->mNumUVComponents[c] = pMesh->mNumUVComponents[c]; pcMesh->mTextureCoords[c] = new aiVector3D[iOutVertexNum]; } vFaces.reserve(iEstimatedSize); // (we will also need to copy the array of indices) while (iBase < pMesh->mNumFaces) { // allocate a new array const unsigned int iNumIndices = pMesh->mFaces[iBase].mNumIndices; // doesn't catch degenerates but is quite fast unsigned int iNeed = 0; for (unsigned int v = 0; v < iNumIndices;++v) { unsigned int iIndex = pMesh->mFaces[iBase].mIndices[v]; // check whether we do already have this vertex if (0xFFFFFFFF == avWasCopied[iIndex]) { iNeed++; } } if (pcMesh->mNumVertices + iNeed > iOutVertexNum) { // don't use this face break; } vFaces.push_back(aiFace()); aiFace& rFace = vFaces.back(); // setup face type and number of indices rFace.mNumIndices = iNumIndices; rFace.mIndices = new unsigned int[iNumIndices]; // need to update the output primitive types switch (rFace.mNumIndices) { case 1: pcMesh->mPrimitiveTypes |= aiPrimitiveType_POINT; break; case 2: pcMesh->mPrimitiveTypes |= aiPrimitiveType_LINE; break; case 3: pcMesh->mPrimitiveTypes |= aiPrimitiveType_TRIANGLE; break; default: pcMesh->mPrimitiveTypes |= aiPrimitiveType_POLYGON; } // and copy the contents of the old array, offset by current base for (unsigned int v = 0; v < iNumIndices;++v) { unsigned int iIndex = pMesh->mFaces[iBase].mIndices[v]; // check whether we do already have this vertex if (0xFFFFFFFF != avWasCopied[iIndex]) { rFace.mIndices[v] = avWasCopied[iIndex]; continue; } // copy positions pcMesh->mVertices[pcMesh->mNumVertices] = (pMesh->mVertices[iIndex]); // copy normals if (pMesh->HasNormals()) { pcMesh->mNormals[pcMesh->mNumVertices] = (pMesh->mNormals[iIndex]); } // copy tangents/bitangents if (pMesh->HasTangentsAndBitangents()) { pcMesh->mTangents[pcMesh->mNumVertices] = (pMesh->mTangents[iIndex]); pcMesh->mBitangents[pcMesh->mNumVertices] = (pMesh->mBitangents[iIndex]); } // texture coordinates for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS;++c) { if (pMesh->HasTextureCoords( c)) { pcMesh->mTextureCoords[c][pcMesh->mNumVertices] = pMesh->mTextureCoords[c][iIndex]; } } // vertex colors for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS;++c) { if (pMesh->HasVertexColors( c)) { pcMesh->mColors[c][pcMesh->mNumVertices] = pMesh->mColors[c][iIndex]; } } // check whether we have bone weights assigned to this vertex rFace.mIndices[v] = pcMesh->mNumVertices; if (avPerVertexWeights) { VertexWeightTable& table = avPerVertexWeights[ pcMesh->mNumVertices ]; if( !table.empty() ) { for (VertexWeightTable::const_iterator iter = table.begin(); iter != table.end();++iter) { // allocate the bone weight array if necessary BoneWeightList* pcWeightList = (BoneWeightList*)pcMesh->mBones[(*iter).first]; if (nullptr == pcWeightList) { pcMesh->mBones[(*iter).first] = (aiBone*)(pcWeightList = new BoneWeightList()); } pcWeightList->push_back(aiVertexWeight(pcMesh->mNumVertices,(*iter).second)); } } } avWasCopied[iIndex] = pcMesh->mNumVertices; pcMesh->mNumVertices++; } ++iBase; if(pcMesh->mNumVertices == iOutVertexNum) { // break here. The face is only added if it was complete break; } } // check which bones we'll need to create for this submesh if (pMesh->HasBones()) { aiBone** ppCurrent = pcMesh->mBones; for (unsigned int k = 0; k < pMesh->mNumBones;++k) { // check whether the bone is existing BoneWeightList* pcWeightList; pcWeightList = (BoneWeightList *)pcMesh->mBones[k]; if (nullptr != pcWeightList) { aiBone *pcOldBone = pMesh->mBones[k]; aiBone* pcOut( nullptr ); *ppCurrent++ = pcOut = new aiBone(); pcOut->mName = aiString(pcOldBone->mName); pcOut->mOffsetMatrix = pcOldBone->mOffsetMatrix; pcOut->mNumWeights = (unsigned int)pcWeightList->size(); pcOut->mWeights = new aiVertexWeight[pcOut->mNumWeights]; // copy the vertex weights ::memcpy(pcOut->mWeights,&pcWeightList->operator[](0), pcOut->mNumWeights * sizeof(aiVertexWeight)); // delete the temporary bone weight list delete pcWeightList; pcMesh->mNumBones++; } } } // copy the face list to the mesh pcMesh->mFaces = new aiFace[vFaces.size()]; pcMesh->mNumFaces = (unsigned int)vFaces.size(); for (unsigned int p = 0; p < pcMesh->mNumFaces;++p) { pcMesh->mFaces[p] = vFaces[p]; } // add the newly created mesh to the list avList.push_back(std::pair(pcMesh,a)); if (iBase == pMesh->mNumFaces) { // have all faces ... finish the outer loop, too break; } } // delete the per-vertex weight list again delete[] avPerVertexWeights; // now delete the old mesh data delete pMesh; return; } avList.push_back(std::pair(pMesh,a)); }