4.16 Dynamic Shadow Artifacts

I have been seeing dynamic shadow artifacts on 4.16.0 and 4.16.1 using the packaged engine as well as built from source. To recreate, I have created a new level, added a directional light and a cube, set the cube to movable, and rotate the objects to create a self shadow on the cube. The issue is only present when the engine scalability settings are set to High, Epic, or Cinematic, but go away when set to Low or Medium. I have recreated this issue on separate machines with windows 7 and windows 10. Both machines have Nvidia Quadro hardware from different generations. I have updated to the latest Nvidia drivers. Has this issue been seen elsewhere? I have not found any bug submissions related at this point. Let me know if I can clarify anything.


Thanks for the reply. I suspected this was some sort of regression, but verified that it was consistent with 4.15. I did some further investigations, and if I understand correctly this is only an issue with directional light, on a movable object, with large flat surfaces. That seems to explain when I didn’t really notice until I created this artificial/simple scenario.

Hello .gaspar

The lines that you see is appear when you rotate and adjust the light in “Z” axis. I got that lines between 70-90 degree angles. “Under Cascaded Shadow Maps” tab there is an option called “Num Dynamic Shadow Cascades”. If you change the value from 3(default) to 1 or 4 you will see the difference. I think this is not a “bug” but something might needs improvement.