How to set the Lightmap Coordinate Index in C++?

Development Rendering
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1

I am creating Static Meshes in C++ from ProceduralMeshComponent similar to how it is done here, that is:

FStaticMeshSourceModel* SrcModel = new (StaticMesh->SourceModels) FStaticMeshSourceModel();
SrcModel->BuildSettings.bRecomputeNormals = false;
SrcModel->BuildSettings.bRecomputeTangents = false;
SrcModel->BuildSettings.bRemoveDegenerates = false;
SrcModel->BuildSettings.bUseHighPrecisionTangentBasis = false;
SrcModel->BuildSettings.bUseFullPrecisionUVs = false;
SrcModel->BuildSettings.bGenerateLightmapUVs = true;
SrcModel->BuildSettings.SrcLightmapIndex = 0;
SrcModel->BuildSettings.DstLightmapIndex = 1;
SrcModel->RawMeshBulkData->SaveRawMesh(RawMesh);
// Copy materials to new mesh
for (UMaterialInterface* Material : MeshMaterials)
{
	StaticMesh->StaticMaterials.Add(FStaticMaterial(Material));
}

//Set the Imported version before calling the build
StaticMesh->ImportVersion = EImportStaticMeshVersion::LastVersion;

// Build mesh from source
StaticMesh->Build(false);
StaticMesh->PostEditChange();

But when I look at the meshes created like that in the Unreal Editor, they all have their Lightmap Coordinate Index set to the channel 0, which is wrong, since the automatical lightmap UVs are created in the channel 1. How can I change the channel upon mesh creation in the code?

2

Bumping this. If you’ve found a solution since this was posted, I’d love to know as well, looking for a way to set Lightmap Coordinate Index through BPs (or c++ if necessary).