Hi, I’m new to UE4 and just working my way through getting a nice clean lightmap & set of lighting UVs on my furniture models here in a test scene. I’ve been getting black artifacts and i thought they were just the result of too many small UV shells and seeing the black pixels pulled in at the shell edges so I started combining more of the smaller UV shells and that helped but here I have an issue that is not at the edge of a UV shell and I don’t know what I am seeing.
In shadow the mesh shows black jaggies like the rough edge of a UV shell in the lightmap but it isn’t at the edge of the shell and it goes away in full illumination. I have screen shots here of the area under a dynamic shadow; when lit there’s no artifact; when the shadow passes across the area you see jaggies. I also have a grab here of the UVs on the front face of the armrest showing how the hard edges arent at the edge of the shell. They are, however, at a hard normal edge on the mesh - could this be part of the issue? Smoothing group/hard normal artifacts??