/**
* Adds Fbx Clusters necessary to skin a skeletal mesh to the bones in the BoneNodes list
*/
void FFbxExporter::BindMeshToSkeleton(const USkeletalMesh* SkelMesh, FbxNode* MeshRootNode, TArray<FbxNode*>& BoneNodes)
{
const FSkeletalMeshResource* SkelMeshResource = SkelMesh->GetImportedResource();
const FStaticLODModel& SourceModel = SkelMeshResource->LODModels[0];
const int32 VertexCount = SourceModel.NumVertices;
FbxAMatrix MeshMatrix;
FbxScene* lScene = MeshRootNode->GetScene();
if( lScene )
{
MeshMatrix = MeshRootNode->EvaluateGlobalTransform();
}
FbxGeometry* MeshAttribute = (FbxGeometry*) MeshRootNode->GetNodeAttribute();
FbxSkin* Skin = FbxSkin::Create(Scene, "");
const int32 BoneCount = BoneNodes.Num();
for(int32 BoneIndex = 0; BoneIndex < BoneCount; ++BoneIndex)
{
FbxNode* BoneNode = BoneNodes[BoneIndex];
// Create the deforming cluster
FbxCluster *CurrentCluster = FbxCluster::Create(Scene,"");
CurrentCluster->SetLink(BoneNode);
CurrentCluster->SetLinkMode(FbxCluster::eTotalOne);
// Add all the vertices that are weighted to the current skeletal bone to the cluster
// NOTE: the bone influence indices contained in the vertex data are based on a per-chunk
// list of verts. The convert the chunk bone index to the mesh bone index, the chunk's
// boneMap is needed
int32 VertIndex = 0;
const int32 SectionCount = SourceModel.Sections.Num();
for(int32 SectionIndex = 0; SectionIndex < SectionCount; ++SectionIndex)
{
const FSkelMeshSection& Section = SourceModel.Sections[SectionIndex];
for(int32 SoftIndex = 0; SoftIndex < Section.SoftVertices.Num(); ++SoftIndex)
{
const FSoftSkinVertex& Vert = Section.SoftVertices[SoftIndex];
for(int32 InfluenceIndex = 0; InfluenceIndex < MAX_TOTAL_INFLUENCES; ++InfluenceIndex)
{
int32 InfluenceBone = Section.BoneMap[ Vert.InfluenceBones[InfluenceIndex] ];
float InfluenceWeight = Vert.InfluenceWeights[InfluenceIndex] / 255.f;
if(InfluenceBone == BoneIndex && InfluenceWeight > 0.f)
{
CurrentCluster->AddControlPointIndex(VertIndex, InfluenceWeight);
}
}
++VertIndex;
}
}
// Now we have the Patch and the skeleton correctly positioned,
// set the Transform and TransformLink matrix accordingly.
CurrentCluster->SetTransformMatrix(MeshMatrix);
FbxAMatrix LinkMatrix;
if( lScene )
{
LinkMatrix = BoneNode->EvaluateGlobalTransform();
}
CurrentCluster->SetTransformLinkMatrix(LinkMatrix);
// Add the clusters to the mesh by creating a skin and adding those clusters to that skin.
Skin->AddCluster(CurrentCluster);
}
// Add the skin to the mesh after the clusters have been added
MeshAttribute->AddDeformer(Skin);
}
void ExportFbxMesh(const Value& obj)
{
string name = obj["Name"].GetString();
FbxNode* pNode = FbxNode::Create(pManager, name.c_str());
FbxMesh* pMesh = FbxMesh::Create(pManager, name.c_str());
pNode->AddNodeAttribute(pMesh);
pScene->GetRootNode()->AddChild(pNode);
int numVertex = obj["NumVertex"].GetInt();
{
pMesh->InitControlPoints(numVertex);
FbxVector4* lControlPoints = pMesh->GetControlPoints();
const Value& pos = obj["Position"];
for (int i = 0; i < numVertex; i++)
{
double x = pos[i * 3 + 0].GetDouble();
x = -x;
double y = pos[i * 3 + 1].GetDouble();
double z = pos[i * 3 + 2].GetDouble();
lControlPoints[i] = FbxVector4(x, y, z);
}
}
{
FbxGeometryElementNormal* lGeometryElementNormal = pMesh->CreateElementNormal();
lGeometryElementNormal->SetMappingMode(FbxGeometryElement::eByControlPoint);
lGeometryElementNormal->SetReferenceMode(FbxGeometryElement::eDirect);
FbxLayerElementArrayTemplate<FbxVector4>& array = lGeometryElementNormal->GetDirectArray();
const Value& normal = obj["Normal"];
for (int i = 0; i < numVertex; i++)
{
double x = normal[i * 3 + 0].GetDouble();
x = -x;
double y = normal[i * 3 + 1].GetDouble();
double z = normal[i * 3 + 2].GetDouble();
array.Add(FbxVector4(x, y, z));
}
}
{
FbxGeometryElementUV* lUVDiffuseElement = pMesh->CreateElementUV("DiffuseUV");
FBX_ASSERT(lUVDiffuseElement != NULL);
lUVDiffuseElement->SetMappingMode(FbxGeometryElement::eByControlPoint);
lUVDiffuseElement->SetReferenceMode(FbxGeometryElement::eDirect);
FbxLayerElementArrayTemplate<FbxVector2>& array = lUVDiffuseElement->GetDirectArray();
const Value& v = obj["UV0"];
for (int i = 0; i < numVertex; i++)
{
double x = v[i * 2 + 0].GetDouble();
double y = v[i * 2 + 1].GetDouble();
array.Add(FbxVector2(x, y));
}
}
{
const Value& color = obj["Color"];
if (!color.IsNull())
{
FbxGeometryElementVertexColor* pColorElement = pMesh->CreateElementVertexColor();
FBX_ASSERT(pColorElement != NULL);
pColorElement->SetMappingMode(FbxGeometryElement::eByControlPoint);
pColorElement->SetReferenceMode(FbxGeometryElement::eDirect);
FbxLayerElementArrayTemplate<FbxColor>& array = pColorElement->GetDirectArray();
for (int i = 0; i < numVertex; i++)
{
double r = color[i * 4 + 0].GetDouble();
double g = color[i * 4 + 1].GetDouble();
double b = color[i * 4 + 2].GetDouble();
double a = color[i * 4 + 3].GetDouble();
array.Add(FbxColor(r, g, b, a));
}
}
}
{
const Value& Indeices = obj["Indeices"];
for (uint32_t subMesh = 0; subMesh < Indeices.Size(); subMesh++)
{
const Value& index0 = Indeices[subMesh];
int numIndex = index0.Size();
printf("index %d\n", numIndex);
for (int i = 0; i < numIndex / 3; i++)
{
pMesh->BeginPolygon(-1, -1, subMesh);
int index[3] = {
index0[i * 3 + 0].GetInt(),
index0[i * 3 + 1].GetInt(),
index0[i * 3 + 2].GetInt(),
};
pMesh->AddPolygon(index[0]);
pMesh->AddPolygon(index[2]);
pMesh->AddPolygon(index[1]);
pMesh->EndPolygon();
}
}
}
//////////////////////////////////////////////////////////////////////////
// export skin
const Value& boneIndex = obj["BoneIndex"];
if (!boneIndex.IsNull())
{
if (fbxBones.empty())
{
printf("no bones, can not export skin");
return;
}
const Value& boneWeight = obj["BoneWeight"];
vector<FbxCluster*> clusters(fbxBones.size(), NULL);
for (uint32_t i = 0; i < fbxBones.size(); i++) {
FbxCluster* pCluster = FbxCluster::Create(pScene, "");
pCluster->SetLink(fbxBones[i]);
pCluster->SetLinkMode(FbxCluster::eTotalOne);
clusters[i] = pCluster;
}
for (int i = 0; i < numVertex; i++) {
for (int j = 0; j < 4; j++) {
int bone = boneIndex[i * 4 + j].GetInt();
double weight = boneWeight[i * 4 + j].GetDouble();
clusters[bone]->AddControlPointIndex(i, weight);
}
}
FbxSkin* lSkin = FbxSkin::Create(pScene, "");
FbxScene* p = pNode->GetScene();
FbxAMatrix modelMatrix = pNode->EvaluateGlobalTransform();
for (uint32_t i = 0; i < clusters.size(); i++) {
clusters[i]->SetTransformMatrix(modelMatrix);
FbxAMatrix boneMatrix = fbxBones[i]->EvaluateGlobalTransform();
clusters[i]->SetTransformLinkMatrix(boneMatrix);
lSkin->AddCluster(clusters[i]);
}
pMesh->AddDeformer(lSkin);
}
}
