GPU lightmass causes strange artefacts

Hi, does anyone else have issues with the GPU light

mass causing strange artefacts?

These weird square shapes in the build can happen at different places. Also were different lightmaps join each other there are more strange artefacts that I can get rid of. CPU bakes are fine and are seamless but the GPU lightmass seems to have issues. I’ve tried increasing GPULM samples and lightmap resolutions but they still appear.

Any help much appreciated.

Did you figure this out yet? Im having a similar issue. Static actors are fine but dynamic actors get this weird black blocks all over them.

I just disabled VT to see if this helps at all.

If your lightmap UV’s are split where those artifacts are showing up then that’s likely the cause, it probably can’t smooth the lightmap across a separate UV islands. You’d need to have lightmap UV’s where lightmap seams aren’t in places like that.

Did it helped? I have the same square artefacts.

Did you had any luck of solving this issue? I have the same problem in my project.