Square shadows in "sections" get painted in and vanish...

Development Rendering
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1

Our team has created a small game and it is in use. However a odd issue cropped up and we are unsure what causes it. Please have a look in the youtube video attached. In short:

  1. Square shadows get “painted in” by the user walking over them.

  2. These will presist if you stand in the zone and vanish if you leave - only to have new places in the room accept it.

  3. Regions can be side by side and one gets painted in and another one not. Can it be related to a texture repeat or something? It also occurs across the floor and up on the wall, so - we are struggling to make a theory of what is wrong. Any pointers would be very helpful here.

The solution is running on UR 5.3.2, with lumen running. virtual shadows on.
Video of issue on Youtube

2

That looks like some kind of lumen issue, where the texels on the surface cache aren’t getting cleared. The fact that they vanish after time also convinces me, as lumen flushes and refreshes bad history away once it’s time for the probes to update.

Of course, that sparse updating scheme is also used for VSMs, bt I’ve never seen an error of this nature before. If you disable VSMs, does the issue persist?

3

This issue can occur with VSMs if the bounds of the shadow-casting object are not set correctly.
Enable Show->Visualize->Out of Bounds Pixels in the viewport and check if your character is drawing outside of it’s mesh bounds when animating.