I have been working on an editor tool to diagnose some general asset problems and I noticed that in UStaticMesh there is a function to detect out of bounds / overlapping lightmap uv’s but no matter what I do, I cannot get any errors for overlapping UV’s, only out of bounds.
TArray<FString> MissingUVErrors;
TArray<FString> BadUVErrors;
TArray<FString> UVSuccessMessages;
Mesh->CheckLightMapUVs(Mesh, MissingUVErrors, BadUVErrors, UVSuccessMessages);
Mesh is a reference to a UStaticMesh Object.
CheckLightmapUVs( ) will check for overlapping or out of bounds error messages. On the image below, it does return one BadUVErrors in the FString array but when I debug through the function, it is because the result is based on:
bool result1 = IsPointInTriangle(CurTriangleUVCentroid, OtherTriangleUVs );
bool result2 = IsPointInTriangle(OtherTriangleUVCentroid, CurTriangleUVs );
if( result1 || result2)
{
++OverlappingLightMapUVTriangleCountOUT;
++TriangleOverlapCounts[ CurTri ];
++OverlappingLightMapUVTriangleCountOUT;
++TriangleOverlapCounts[ OtherTri ];
}
IsPointInTriangle( ) isn’t ever returning true.
As a secondary option, below is an image that comes back with zero errors and a “success” message:
1 Get a reference to a UStaticMesh object that has a LightmapUVCoordinateIndex set to 1 (should be by default)
2 Make sure that there is overlapping UV’s in the lightmap uv.
3 Call CheckLightMapUVs( ) on the mesh.
RESULT:
MissingUVErrors, BadUVErrors will hold no results.
UVSuccessMessages will.