I’ve met the problem during the render of groom cache both in UE4.27 and UE5.0 - groom looked stuttering when moved, like it was missmatching character geometry.
What I’ve noticed investigating this that’s when viewing groom in viewport I noticed that it’s kind of takes a couple secs for groom to set correctly and I was looking for a way to give render that time during render to kind of warm up each frame.
The solution was to add more temporal samples (32 samples worked) to kind of warm up each render frame.
Issue (aa enabled, 1 temporal 1 spatial sample):
Solved (32 temporal samples):
Rendering process (you can see that first samples are kind of stattering but number of samples helps):
Reported issue to unreal, hopefully they’ll answer. (Case # 00479141 (@21.09.22): Groom cache stuttering / miss match during render)
List of similar issues I’ve found looking for solution (it’s possible that my solution could solve some of them):