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GLTF Importer: Build a list of the actual vertices so it works well with shared attribute lists

pull/5003/head
Florian Born 2023-03-09 19:06:58 +01:00
parent 0ed957f70a
commit dfd70b5c10
3 changed files with 78 additions and 43 deletions
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2
code/AssetLib/glTF2/glTF2Asset.h
View File

@ -565,7 +565,7 @@ struct Accessor : public Object {
inline size_t GetMaxByteSize();
template <class T>
void ExtractData(T *&outData);
size_t ExtractData(T *&outData, const std::vector<unsigned int> *remappingIndices = nullptr);
void WriteData(size_t count, const void *src_buffer, size_t src_stride);
void WriteSparseValues(size_t count, const void *src_data, size_t src_dataStride);

19
code/AssetLib/glTF2/glTF2Asset.inl
View File

@ -962,14 +962,15 @@ inline size_t Accessor::GetMaxByteSize() {
}
template <class T>
void Accessor::ExtractData(T *&outData) {
size_t Accessor::ExtractData(T *&outData, const std::vector<unsigned int> *remappingIndices) {
uint8_t *data = GetPointer();
if (!data) {
throw DeadlyImportError("GLTF2: data is null when extracting data from ", getContextForErrorMessages(id, name));
}
const size_t usedCount = (remappingIndices != nullptr) ? remappingIndices->size() : count;
const size_t elemSize = GetElementSize();
const size_t totalSize = elemSize * count;
const size_t totalSize = elemSize * usedCount;
const size_t stride = GetStride();
@ -980,18 +981,20 @@ void Accessor::ExtractData(T *&outData) {
}
const size_t maxSize = GetMaxByteSize();
if (count * stride > maxSize) {
throw DeadlyImportError("GLTF: count*stride ", (count * stride), " > maxSize ", maxSize, " in ", getContextForErrorMessages(id, name));
if (usedCount * stride > maxSize) {
throw DeadlyImportError("GLTF: count*stride ", (usedCount * stride), " > maxSize ", maxSize, " in ", getContextForErrorMessages(id, name));
}
outData = new T[count];
if (stride == elemSize && targetElemSize == elemSize) {
outData = new T[usedCount];
if (remappingIndices == nullptr && stride == elemSize && targetElemSize == elemSize) {
memcpy(outData, data, totalSize);
} else {
for (size_t i = 0; i < count; ++i) {
memcpy(outData + i, data + i * stride, elemSize);
for (size_t i = 0; i < usedCount; ++i) {
size_t srcIdx = remappingIndices != nullptr ? static_cast<size_t>((*remappingIndices)[i]) : i;
memcpy(outData + i, data + srcIdx * stride, elemSize);
}
}
return usedCount;
}
inline void Accessor::WriteData(size_t _count, const void *src_buffer, size_t src_stride) {

100
code/AssetLib/glTF2/glTF2Importer.cpp
View File

@ -453,6 +453,12 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
unsigned int k = 0;
meshOffsets.clear();
const unsigned int unusedIndex = ~0;
std::vector<unsigned int> usedVertexIndices;
std::vector<unsigned int> reverseMappingIndices;
std::vector<unsigned int> indexBuffer;
for (unsigned int m = 0; m < r.meshes.Size(); ++m) {
Mesh &mesh = r.meshes[m];
@ -462,6 +468,36 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
for (unsigned int p = 0; p < mesh.primitives.size(); ++p) {
Mesh::Primitive &prim = mesh.primitives[p];
// extract used vertices:
bool useIndexBuffer = prim.indices;
std::vector<unsigned int>* usedVertexIndicesPtr = nullptr;
if (useIndexBuffer) {
size_t count = prim.indices->count;
indexBuffer.resize(count);
usedVertexIndices.clear();
reverseMappingIndices.clear();
usedVertexIndices.reserve(count / 3); // this is a very rough heuristic to reduce re-allocations
usedVertexIndicesPtr = &usedVertexIndices;
Accessor::Indexer data = prim.indices->GetIndexer();
if (!data.IsValid()) {
throw DeadlyImportError("GLTF: Invalid accessor without data in mesh ", getContextForErrorMessages(mesh.id, mesh.name));
}
// Build the vertex remapping table and the modified index buffer (used later instead of the original one)
// In case no index buffer is used, the original vertex arrays are being used so no remapping is required in the first place.
for (unsigned int i = 0; i < count; ++i) {
unsigned int index = data.GetUInt(i);
if (index >= reverseMappingIndices.size()) {
reverseMappingIndices.resize(index + 1, unusedIndex);
}
if (reverseMappingIndices[index] == unusedIndex) {
reverseMappingIndices[index] = static_cast<unsigned int>(usedVertexIndices.size());
usedVertexIndices.push_back(index);
}
indexBuffer[i] = reverseMappingIndices[index];
}
}
aiMesh *aim = new aiMesh();
meshes.push_back(std::unique_ptr<aiMesh>(aim));
@ -493,26 +529,27 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
Mesh::Primitive::Attributes &attr = prim.attributes;
size_t numAllVertices = 0;
if (!attr.position.empty() && attr.position[0]) {
aim->mNumVertices = static_cast<unsigned int>(attr.position[0]->count);
attr.position[0]->ExtractData(aim->mVertices);
numAllVertices = attr.position[0]->count;
aim->mNumVertices = static_cast<unsigned int>(attr.position[0]->ExtractData(aim->mVertices, usedVertexIndicesPtr));
}
if (!attr.normal.empty() && attr.normal[0]) {
if (attr.normal[0]->count != aim->mNumVertices) {
if (attr.normal[0]->count != numAllVertices) {
DefaultLogger::get()->warn("Normal count in mesh \"", mesh.name, "\" does not match the vertex count, normals ignored.");
} else {
attr.normal[0]->ExtractData(aim->mNormals);
attr.normal[0]->ExtractData(aim->mNormals, usedVertexIndicesPtr);
// only extract tangents if normals are present
if (!attr.tangent.empty() && attr.tangent[0]) {
if (attr.tangent[0]->count != aim->mNumVertices) {
if (attr.tangent[0]->count != numAllVertices) {
DefaultLogger::get()->warn("Tangent count in mesh \"", mesh.name, "\" does not match the vertex count, tangents ignored.");
} else {
// generate bitangents from normals and tangents according to spec
Tangent *tangents = nullptr;
attr.tangent[0]->ExtractData(tangents);
attr.tangent[0]->ExtractData(tangents, usedVertexIndicesPtr);
aim->mTangents = new aiVector3D[aim->mNumVertices];
aim->mBitangents = new aiVector3D[aim->mNumVertices];
@ -529,7 +566,7 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
}
for (size_t c = 0; c < attr.color.size() && c < AI_MAX_NUMBER_OF_COLOR_SETS; ++c) {
if (attr.color[c]->count != aim->mNumVertices) {
if (attr.color[c]->count != numAllVertices) {
DefaultLogger::get()->warn("Color stream size in mesh \"", mesh.name,
"\" does not match the vertex count");
continue;
@ -537,7 +574,7 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
auto componentType = attr.color[c]->componentType;
if (componentType == glTF2::ComponentType_FLOAT) {
attr.color[c]->ExtractData(aim->mColors[c]);
attr.color[c]->ExtractData(aim->mColors[c], usedVertexIndicesPtr);
} else {
if (componentType == glTF2::ComponentType_UNSIGNED_BYTE) {
aim->mColors[c] = GetVertexColorsForType<unsigned char>(attr.color[c]);
@ -552,13 +589,13 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
continue;
}
if (attr.texcoord[tc]->count != aim->mNumVertices) {
if (attr.texcoord[tc]->count != numAllVertices) {
DefaultLogger::get()->warn("Texcoord stream size in mesh \"", mesh.name,
"\" does not match the vertex count");
continue;
}
attr.texcoord[tc]->ExtractData(aim->mTextureCoords[tc]);
attr.texcoord[tc]->ExtractData(aim->mTextureCoords[tc], usedVertexIndicesPtr);
aim->mNumUVComponents[tc] = attr.texcoord[tc]->GetNumComponents();
aiVector3D *values = aim->mTextureCoords[tc];
@ -583,11 +620,11 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
Mesh::Primitive::Target &target = targets[i];
if (needPositions) {
if (target.position[0]->count != aim->mNumVertices) {
if (target.position[0]->count != numAllVertices) {
ASSIMP_LOG_WARN("Positions of target ", i, " in mesh \"", mesh.name, "\" does not match the vertex count");
} else {
aiVector3D *positionDiff = nullptr;
target.position[0]->ExtractData(positionDiff);
target.position[0]->ExtractData(positionDiff, usedVertexIndicesPtr);
for (unsigned int vertexId = 0; vertexId < aim->mNumVertices; vertexId++) {
aiAnimMesh.mVertices[vertexId] += positionDiff[vertexId];
}
@ -595,11 +632,11 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
}
}
if (needNormals) {
if (target.normal[0]->count != aim->mNumVertices) {
if (target.normal[0]->count != numAllVertices) {
ASSIMP_LOG_WARN("Normals of target ", i, " in mesh \"", mesh.name, "\" does not match the vertex count");
} else {
aiVector3D *normalDiff = nullptr;
target.normal[0]->ExtractData(normalDiff);
target.normal[0]->ExtractData(normalDiff, usedVertexIndicesPtr);
for (unsigned int vertexId = 0; vertexId < aim->mNumVertices; vertexId++) {
aiAnimMesh.mNormals[vertexId] += normalDiff[vertexId];
}
@ -610,14 +647,14 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
if (!aiAnimMesh.HasNormals()) {
// prevent nullptr access to aiAnimMesh.mNormals below when no normals are available
ASSIMP_LOG_WARN("Bitangents of target ", i, " in mesh \"", mesh.name, "\" can't be computed, because mesh has no normals.");
} else if (target.tangent[0]->count != aim->mNumVertices) {
} else if (target.tangent[0]->count != numAllVertices) {
ASSIMP_LOG_WARN("Tangents of target ", i, " in mesh \"", mesh.name, "\" does not match the vertex count");
} else {
Tangent *tangent = nullptr;
attr.tangent[0]->ExtractData(tangent);
attr.tangent[0]->ExtractData(tangent, usedVertexIndicesPtr);
aiVector3D *tangentDiff = nullptr;
target.tangent[0]->ExtractData(tangentDiff);
target.tangent[0]->ExtractData(tangentDiff, usedVertexIndicesPtr);
for (unsigned int vertexId = 0; vertexId < aim->mNumVertices; ++vertexId) {
tangent[vertexId].xyz += tangentDiff[vertexId];
@ -641,20 +678,15 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
aiFace *facePtr = nullptr;
size_t nFaces = 0;
if (prim.indices) {
size_t count = prim.indices->count;
Accessor::Indexer data = prim.indices->GetIndexer();
if (!data.IsValid()) {
throw DeadlyImportError("GLTF: Invalid accessor without data in mesh ", getContextForErrorMessages(mesh.id, mesh.name));
}
if (useIndexBuffer) {
size_t count = indexBuffer.size();
switch (prim.mode) {
case PrimitiveMode_POINTS: {
nFaces = count;
facePtr = faces = new aiFace[nFaces];
for (unsigned int i = 0; i < count; ++i) {
SetFaceAndAdvance1(facePtr, aim->mNumVertices, data.GetUInt(i));
SetFaceAndAdvance1(facePtr, aim->mNumVertices, indexBuffer[i]);
}
break;
}
@ -667,7 +699,7 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
}
facePtr = faces = new aiFace[nFaces];
for (unsigned int i = 0; i < count; i += 2) {
SetFaceAndAdvance2(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1));
SetFaceAndAdvance2(facePtr, aim->mNumVertices, indexBuffer[i], indexBuffer[i + 1]);
}
break;
}
@ -676,12 +708,12 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
case PrimitiveMode_LINE_STRIP: {
nFaces = count - ((prim.mode == PrimitiveMode_LINE_STRIP) ? 1 : 0);
facePtr = faces = new aiFace[nFaces];
SetFaceAndAdvance2(facePtr, aim->mNumVertices, data.GetUInt(0), data.GetUInt(1));
SetFaceAndAdvance2(facePtr, aim->mNumVertices, indexBuffer[0], indexBuffer[1]);
for (unsigned int i = 2; i < count; ++i) {
SetFaceAndAdvance2(facePtr, aim->mNumVertices, data.GetUInt(i - 1), data.GetUInt(i));
SetFaceAndAdvance2(facePtr, aim->mNumVertices, indexBuffer[i - 1], indexBuffer[i]);
}
if (prim.mode == PrimitiveMode_LINE_LOOP) { // close the loop
SetFaceAndAdvance2(facePtr, aim->mNumVertices, data.GetUInt(static_cast<int>(count) - 1), faces[0].mIndices[0]);
SetFaceAndAdvance2(facePtr, aim->mNumVertices, indexBuffer[static_cast<int>(count) - 1], faces[0].mIndices[0]);
}
break;
}
@ -694,7 +726,7 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
}
facePtr = faces = new aiFace[nFaces];
for (unsigned int i = 0; i < count; i += 3) {
SetFaceAndAdvance3(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2));
SetFaceAndAdvance3(facePtr, aim->mNumVertices, indexBuffer[i], indexBuffer[i + 1], indexBuffer[i + 2]);
}
break;
}
@ -705,10 +737,10 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
// The ordering is to ensure that the triangles are all drawn with the same orientation
if ((i + 1) % 2 == 0) {
// For even n, vertices n + 1, n, and n + 2 define triangle n
SetFaceAndAdvance3(facePtr, aim->mNumVertices, data.GetUInt(i + 1), data.GetUInt(i), data.GetUInt(i + 2));
SetFaceAndAdvance3(facePtr, aim->mNumVertices, indexBuffer[i + 1], indexBuffer[i], indexBuffer[i + 2]);
} else {
// For odd n, vertices n, n+1, and n+2 define triangle n
SetFaceAndAdvance3(facePtr, aim->mNumVertices, data.GetUInt(i), data.GetUInt(i + 1), data.GetUInt(i + 2));
SetFaceAndAdvance3(facePtr, aim->mNumVertices, indexBuffer[i], indexBuffer[i + 1], indexBuffer[i + 2]);
}
}
break;
@ -716,9 +748,9 @@ void glTF2Importer::ImportMeshes(glTF2::Asset &r) {
case PrimitiveMode_TRIANGLE_FAN:
nFaces = count - 2;
facePtr = faces = new aiFace[nFaces];
SetFaceAndAdvance3(facePtr, aim->mNumVertices, data.GetUInt(0), data.GetUInt(1), data.GetUInt(2));
SetFaceAndAdvance3(facePtr, aim->mNumVertices, indexBuffer[0], indexBuffer[1], indexBuffer[2]);
for (unsigned int i = 1; i < nFaces; ++i) {
SetFaceAndAdvance3(facePtr, aim->mNumVertices, data.GetUInt(0), data.GetUInt(i + 1), data.GetUInt(i + 2));
SetFaceAndAdvance3(facePtr, aim->mNumVertices, indexBuffer[0], indexBuffer[i + 1], indexBuffer[i + 2]);
}
break;
}