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Can't copy FSoftSkinVertex information on android device


I'm copying procedural mesh from skeletal mesh by getting the information of FSoftSkinVertex.

Everything works fine on PC, but looks terrible on android.

It looks like I didn't get the normal, so I print out TangentZ.

It did have values on PC, but didn't on device.

alt text alt text

Wondering why this is happening. Is it because the setting of build to android device? (using arm64)

Here's my code to copy the mesh and my project settings.

             int32 LODIndex = 0;
             FSkeletalMeshLODInfo& SrcLODInfo = GetMesh()->SkeletalMesh->LODInfo[LODIndex];
             // Get the Vertices for this LOD
             TArray<FVector> Vertices;
             FSkeletalMeshResource& SkeletalMeshResource = GetMesh()->MeshObject->GetSkeletalMeshResource();
             FStaticLODModel& StaticLODModel = SkeletalMeshResource.LODModels[LODIndex];
             TArray<FSoftSkinVertex> SoftVertices;
             const int32 NumSections = StaticLODModel.Sections.Num();
             FRawStaticIndexBuffer16or32Interface& IndexBuffer = *StaticLODModel.MultiSizeIndexContainer.GetIndexBuffer();
             //MyVertices as Vertices
             TArray<FVector> MyVertices;
             //WedgeIndices as Triangles?
             //WedgeTangetX as Tangent?
             //WedgeTangetZ as Normal?
             //WedgeTexCoords as UV?
             TArray<FVector2D> MyUV;
             TArray<FColor> Colors;
             float MaxUpLength = 0;
             float MaxForwardLength = 0;
             float MaxRightLength = 0;
             // Map from vert buffer for whole mesh to vert buffer for section of interest
             TMap<int32, int32> MeshToSectionVertMap;
             FMatrix WorldToRoot = GetMesh()->GetComponentTransform().ToMatrixWithScale().Inverse();
             FMatrix ComponentToWorld = GetMesh()->GetComponentTransform().ToMatrixWithScale() * WorldToRoot;
             for (int32 SectionIndex = 0; SectionIndex < NumSections; SectionIndex++) {
                 const FSkelMeshSection& SkelMeshSection = StaticLODModel.Sections[SectionIndex];
                 if (!SkelMeshSection.bDisabled) {
                     // Build 'wedge' info
                     const int32 NumWedges = SkelMeshSection.NumTriangles * 3;
                     for (int32 WedgeIndex = 0; WedgeIndex < NumWedges; WedgeIndex++) {
                         const int32 VertexIndexForWedge = IndexBuffer.Get(SkelMeshSection.BaseIndex + WedgeIndex);
                         int32* NewIndexPtr = MeshToSectionVertMap.Find(VertexIndexForWedge);
                         if (NewIndexPtr != nullptr) {
                             //Copy Triangles
                         else {
                             // Copy position
                             int32 SectionVertIndex = MyVertices.Add(Vertices[VertexIndexForWedge]);
                             const FSoftSkinVertex SoftSkinnedVertex = SoftVertices[VertexIndexForWedge];
                             const FVector TangentX = ComponentToWorld.TransformVector(SoftSkinnedVertex.TangentX);
                             FProcMeshTangent NewTangent(TangentX, 0);
                             // Copy tangents
                             check(MyTangent.Num() == MyVertices.Num());
                             // Copy normal
                             const FVector TangentZ = ComponentToWorld.TransformVector(SoftSkinnedVertex.TangentZ);
                             GEngine->AddOnScreenDebugMessage(-1, 10.0f, FColor::Red, SoftVertices[VertexIndexForWedge].TangentZ.ToString());
                             check(MyNormal.Num() == MyVertices.Num());
                             // Copy UVs
                             MyUV.Add(StaticLODModel.VertexBufferGPUSkin.GetVertexUV(VertexIndexForWedge, 0));
                             check(MyUV.Num() == MyVertices.Num());
                             MeshToSectionVertMap.Add(VertexIndexForWedge, SectionVertIndex);
                             //Copy Triangles
                             SetMaxLength(MyVertices.Top(), MaxUpLength, MaxRightLength, MaxForwardLength);
                             //Copy Colors
                             if (StaticLODModel.ColorVertexBuffer.IsInitialized()) {
                             else {
                 ProcMeshComponent->CreateMeshSection(SectionIndex, MyVertices, MyTriangles, MyNormal, MyUV, Colors, MyTangent, false);
             //Set collision box by length to each edge
             CreateCollisionBox(MaxUpLength, MaxRightLength, MaxForwardLength);
             //// MATERIALS
             for (int32 MatIndex = 0; MatIndex < GetMesh()->GetNumMaterials(); MatIndex++)
                 ProcMeshComponent->SetMaterial(MatIndex, GetMesh()->GetMaterial(MatIndex));

alt text

Product Version: UE 4.17
onpc.png (653.6 kB)
ondevice.jpg (395.2 kB)
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asked Sep 22 '17 at 02:56 AM in C++ Programming

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