I am trying to programatically paint vertices on a mesh based on their material slot. However, I have not found a method to map a vertice to its associated material slot.
I have found FStaticMeshSection:
struct FStaticMeshSection
{
/** The index of the material with which to render this section. */
int32 MaterialIndex;
/** Range of vertices and indices used when rendering this section. */
uint32 FirstIndex;
uint32 NumTriangles;
uint32 MinVertexIndex;
uint32 MaxVertexIndex;
However, MinVertexIndex and MaxVertexIndex don’t seem to work. Is this the method (and I have a bug elsewhere in my code)? Or is there another method to map a vertex to material slot?
For context, this is how I am currently painting the vertices:
uint32 TotalVertices = LODModel.GetNumVertices();
check(InstanceMeshLODInfo->OverrideVertexColors);
check(TotalVertices <= InstanceMeshLODInfo->OverrideVertexColors->GetNumVertices());
for (uint32 VerticeIdx = 0; VerticeIdx < TotalVertices; VerticeIdx++)
{
FColor ColorToSet = DefaultColor;
// uint32 NumOverrideVertexColors = InstanceMeshLODInfo->OverrideVertexColors->GetNumVertices();
// uint32 NumPaintedVertices = InstanceMeshLODInfo->PaintedVertices.Num();
if (VertexIdxToMaterialIdx.Contains(VerticeIdx) && MaterialIndexToColor.Contains(VertexIdxToMaterialIdx[VerticeIdx]))
{
int MaterialIndex = VertexIdxToMaterialIdx[VerticeIdx];
ColorToSet = MaterialIndexToColor[MaterialIndex];
}
InstanceMeshLODInfo->OverrideVertexColors->VertexColor(VerticeIdx) = ColorToSet;
}