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authorsanine <sanine.not@pm.me>2022-04-16 11:55:09 -0500
committersanine <sanine.not@pm.me>2022-04-16 11:55:09 -0500
commitdb81b925d776103326128bf629cbdda576a223e7 (patch)
tree58bea8155c686733310009f6bed7363f91fbeb9d /libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp
parent55860037b14fb3893ba21cf2654c83d349cc1082 (diff)
move 3rd-party librarys into libs/ and add built-in honeysuckle
Diffstat (limited to 'libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp')
-rw-r--r--libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp319
1 files changed, 319 insertions, 0 deletions
diff --git a/libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp b/libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp
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+++ b/libs/assimp/code/AssetLib/Assjson/mesh_splitter.cpp
@@ -0,0 +1,319 @@
+/*
+Assimp2Json
+Copyright (c) 2011, Alexander C. Gessler
+
+Licensed under a 3-clause BSD license. See the LICENSE file for more information.
+
+*/
+
+#include "mesh_splitter.h"
+
+#include <assimp/scene.h>
+
+// ----------------------------------------------------------------------------
+// Note: this is largely based on assimp's SplitLargeMeshes_Vertex process.
+// it is refactored and the coding style is slightly improved, though.
+// ----------------------------------------------------------------------------
+
+// ------------------------------------------------------------------------------------------------
+// Executes the post processing step on the given imported data.
+void MeshSplitter::Execute( aiScene* pScene) {
+ std::vector<std::pair<aiMesh*, unsigned int> > source_mesh_map;
+
+ for( unsigned int a = 0; a < pScene->mNumMeshes; a++) {
+ SplitMesh(a, pScene->mMeshes[a],source_mesh_map);
+ }
+
+ const unsigned int size = static_cast<unsigned int>(source_mesh_map.size());
+ if (size != pScene->mNumMeshes) {
+ // it seems something has been split. rebuild the mesh list
+ delete[] pScene->mMeshes;
+ pScene->mNumMeshes = size;
+ pScene->mMeshes = new aiMesh*[size]();
+
+ for (unsigned int i = 0; i < size;++i) {
+ pScene->mMeshes[i] = source_mesh_map[i].first;
+ }
+
+ // now we need to update all nodes
+ UpdateNode(pScene->mRootNode,source_mesh_map);
+ }
+}
+
+
+// ------------------------------------------------------------------------------------------------
+void MeshSplitter::UpdateNode(aiNode* pcNode, const std::vector<std::pair<aiMesh*, unsigned int> >& source_mesh_map) {
+ // TODO: should better use std::(multi)set for source_mesh_map.
+
+ // for every index in out list build a new entry
+ std::vector<unsigned int> aiEntries;
+ aiEntries.reserve(pcNode->mNumMeshes + 1);
+ for (unsigned int i = 0; i < pcNode->mNumMeshes;++i) {
+ for (unsigned int a = 0, end = static_cast<unsigned int>(source_mesh_map.size()); a < end;++a) {
+ if (source_mesh_map[a].second == pcNode->mMeshes[i]) {
+ aiEntries.push_back(a);
+ }
+ }
+ }
+
+ // now build the new list
+ delete pcNode->mMeshes;
+ pcNode->mNumMeshes = static_cast<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];
+ }
+
+ // recursively update children
+ for (unsigned int i = 0, end = pcNode->mNumChildren; i < end;++i) {
+ UpdateNode ( pcNode->mChildren[i], source_mesh_map );
+ }
+}
+
+static const unsigned int WAS_NOT_COPIED = 0xffffffff;
+
+using PerVertexWeight = std::pair <unsigned int,float>;
+using VertexWeightTable = std::vector <PerVertexWeight>;
+
+// ------------------------------------------------------------------------------------------------
+VertexWeightTable* ComputeVertexBoneWeightTable(const aiMesh* pMesh) {
+ if (!pMesh || !pMesh->mNumVertices || !pMesh->mNumBones) {
+ return nullptr;
+ }
+
+ VertexWeightTable* const avPerVertexWeights = new VertexWeightTable[pMesh->mNumVertices];
+ for (unsigned int i = 0; i < pMesh->mNumBones;++i) {
+
+ aiBone* bone = pMesh->mBones[i];
+ for (unsigned int a = 0; a < bone->mNumWeights;++a) {
+ const aiVertexWeight& weight = bone->mWeights[a];
+ avPerVertexWeights[weight.mVertexId].emplace_back(i,weight.mWeight);
+ }
+ }
+ return avPerVertexWeights;
+}
+
+// ------------------------------------------------------------------------------------------------
+void MeshSplitter :: SplitMesh(unsigned int a, aiMesh* in_mesh, std::vector<std::pair<aiMesh*, unsigned int> >& source_mesh_map) {
+ // TODO: should better use std::(multi)set for source_mesh_map.
+
+ if (in_mesh->mNumVertices <= LIMIT) {
+ source_mesh_map.emplace_back(in_mesh,a);
+ return;
+ }
+
+ // build a per-vertex weight list if necessary
+ VertexWeightTable* avPerVertexWeights = ComputeVertexBoneWeightTable(in_mesh);
+
+ // we need to split this mesh into sub meshes. Estimate submesh size
+ const unsigned int sub_meshes = (in_mesh->mNumVertices / LIMIT) + 1;
+
+ // create a std::vector<unsigned int> to remember which vertices have already
+ // been copied and to which position (i.e. output index)
+ std::vector<unsigned int> was_copied_to;
+ was_copied_to.resize(in_mesh->mNumVertices,WAS_NOT_COPIED);
+
+ // Try to find a good estimate for the number of output faces
+ // per mesh. Add 12.5% as buffer
+ unsigned int size_estimated = in_mesh->mNumFaces / sub_meshes;
+ size_estimated += size_estimated / 8;
+
+ // now generate all submeshes
+ unsigned int base = 0;
+ while (true) {
+ const unsigned int out_vertex_index = LIMIT;
+
+ aiMesh* out_mesh = new aiMesh();
+ out_mesh->mNumVertices = 0;
+ out_mesh->mMaterialIndex = in_mesh->mMaterialIndex;
+
+ // the name carries the adjacency information between the meshes
+ out_mesh->mName = in_mesh->mName;
+
+ typedef std::vector<aiVertexWeight> BoneWeightList;
+ if (in_mesh->HasBones()) {
+ out_mesh->mBones = new aiBone*[in_mesh->mNumBones]();
+ }
+
+ // clear the temporary helper array
+ if (base) {
+ std::fill(was_copied_to.begin(), was_copied_to.end(), WAS_NOT_COPIED);
+ }
+
+ std::vector<aiFace> vFaces;
+
+ // reserve enough storage for most cases
+ if (in_mesh->HasPositions()) {
+ out_mesh->mVertices = new aiVector3D[out_vertex_index];
+ }
+
+ if (in_mesh->HasNormals()) {
+ out_mesh->mNormals = new aiVector3D[out_vertex_index];
+ }
+
+ if (in_mesh->HasTangentsAndBitangents()) {
+ out_mesh->mTangents = new aiVector3D[out_vertex_index];
+ out_mesh->mBitangents = new aiVector3D[out_vertex_index];
+ }
+
+ for (unsigned int c = 0; in_mesh->HasVertexColors(c);++c) {
+ out_mesh->mColors[c] = new aiColor4D[out_vertex_index];
+ }
+
+ for (unsigned int c = 0; in_mesh->HasTextureCoords(c);++c) {
+ out_mesh->mNumUVComponents[c] = in_mesh->mNumUVComponents[c];
+ out_mesh->mTextureCoords[c] = new aiVector3D[out_vertex_index];
+ }
+ vFaces.reserve(size_estimated);
+
+ // (we will also need to copy the array of indices)
+ while (base < in_mesh->mNumFaces) {
+ const unsigned int iNumIndices = in_mesh->mFaces[base].mNumIndices;
+
+ // doesn't catch degenerates but is quite fast
+ unsigned int iNeed = 0;
+ for (unsigned int v = 0; v < iNumIndices;++v) {
+ unsigned int index = in_mesh->mFaces[base].mIndices[v];
+
+ // check whether we do already have this vertex
+ if (WAS_NOT_COPIED == was_copied_to[index]) {
+ iNeed++;
+ }
+ }
+ if (out_mesh->mNumVertices + iNeed > out_vertex_index) {
+ // don't use this face
+ break;
+ }
+
+ vFaces.emplace_back();
+ 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:
+ out_mesh->mPrimitiveTypes |= aiPrimitiveType_POINT;
+ break;
+ case 2:
+ out_mesh->mPrimitiveTypes |= aiPrimitiveType_LINE;
+ break;
+ case 3:
+ out_mesh->mPrimitiveTypes |= aiPrimitiveType_TRIANGLE;
+ break;
+ default:
+ out_mesh->mPrimitiveTypes |= aiPrimitiveType_POLYGON;
+ }
+
+ // and copy the contents of the old array, offset them by current base
+ for (unsigned int v = 0; v < iNumIndices;++v) {
+ const unsigned int index = in_mesh->mFaces[base].mIndices[v];
+
+ // check whether we do already have this vertex
+ if (WAS_NOT_COPIED != was_copied_to[index]) {
+ rFace.mIndices[v] = was_copied_to[index];
+ continue;
+ }
+
+ // copy positions
+ out_mesh->mVertices[out_mesh->mNumVertices] = (in_mesh->mVertices[index]);
+
+ // copy normals
+ if (in_mesh->HasNormals()) {
+ out_mesh->mNormals[out_mesh->mNumVertices] = (in_mesh->mNormals[index]);
+ }
+
+ // copy tangents/bi-tangents
+ if (in_mesh->HasTangentsAndBitangents()) {
+ out_mesh->mTangents[out_mesh->mNumVertices] = (in_mesh->mTangents[index]);
+ out_mesh->mBitangents[out_mesh->mNumVertices] = (in_mesh->mBitangents[index]);
+ }
+
+ // texture coordinates
+ for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_TEXTURECOORDS;++c) {
+ if (in_mesh->HasTextureCoords( c)) {
+ out_mesh->mTextureCoords[c][out_mesh->mNumVertices] = in_mesh->mTextureCoords[c][index];
+ }
+ }
+ // vertex colors
+ for (unsigned int c = 0; c < AI_MAX_NUMBER_OF_COLOR_SETS;++c) {
+ if (in_mesh->HasVertexColors( c)) {
+ out_mesh->mColors[c][out_mesh->mNumVertices] = in_mesh->mColors[c][index];
+ }
+ }
+ // check whether we have bone weights assigned to this vertex
+ rFace.mIndices[v] = out_mesh->mNumVertices;
+ if (avPerVertexWeights) {
+ VertexWeightTable& table = avPerVertexWeights[ out_mesh->mNumVertices ];
+ for (VertexWeightTable::const_iterator iter = table.begin(), end = table.end(); iter != end;++iter) {
+ // allocate the bone weight array if necessary and store it in the mBones field (HACK!)
+ BoneWeightList* weight_list = reinterpret_cast<BoneWeightList*>(out_mesh->mBones[(*iter).first]);
+ if (!weight_list) {
+ weight_list = new BoneWeightList();
+ out_mesh->mBones[(*iter).first] = reinterpret_cast<aiBone*>(weight_list);
+ }
+ weight_list->push_back(aiVertexWeight(out_mesh->mNumVertices,(*iter).second));
+ }
+ }
+
+ was_copied_to[index] = out_mesh->mNumVertices;
+ out_mesh->mNumVertices++;
+ }
+ base++;
+ if(out_mesh->mNumVertices == out_vertex_index) {
+ // break here. The face is only added if it was complete
+ break;
+ }
+ }
+
+ // check which bones we'll need to create for this submesh
+ if (in_mesh->HasBones()) {
+ aiBone** ppCurrent = out_mesh->mBones;
+ for (unsigned int k = 0; k < in_mesh->mNumBones;++k) {
+ // check whether the bone exists
+ BoneWeightList* const weight_list = reinterpret_cast<BoneWeightList*>(out_mesh->mBones[k]);
+
+ if (weight_list) {
+ const aiBone* const bone_in = in_mesh->mBones[k];
+ aiBone* const bone_out = new aiBone();
+ *ppCurrent++ = bone_out;
+ bone_out->mName = aiString(bone_in->mName);
+ bone_out->mOffsetMatrix =bone_in->mOffsetMatrix;
+ bone_out->mNumWeights = (unsigned int)weight_list->size();
+ bone_out->mWeights = new aiVertexWeight[bone_out->mNumWeights];
+
+ // copy the vertex weights
+ ::memcpy(bone_out->mWeights, &(*weight_list)[0],bone_out->mNumWeights * sizeof(aiVertexWeight));
+
+ delete weight_list;
+ out_mesh->mNumBones++;
+ }
+ }
+ }
+
+ // copy the face list to the mesh
+ out_mesh->mFaces = new aiFace[vFaces.size()];
+ out_mesh->mNumFaces = (unsigned int)vFaces.size();
+
+ for (unsigned int p = 0; p < out_mesh->mNumFaces;++p) {
+ out_mesh->mFaces[p] = vFaces[p];
+ }
+
+ // add the newly created mesh to the list
+ source_mesh_map.push_back(std::make_pair(out_mesh,a));
+
+ if (base == in_mesh->mNumFaces) {
+ break;
+ }
+ }
+
+ // delete the per-vertex weight list again
+ delete[] avPerVertexWeights;
+
+ // now delete the old mesh data
+ delete in_mesh;
+}