I have a PRT Loader with the KSW WSM.
The reference mesh has vertex animation, but the pivot stays in place. If I go to a frame other than the reference frame and move the pivot of the reference mesh (without animating it) you can see the particles move, even though the faces they reference do not. I don’t think that’s supposed to happen. It should only be looking at the faces, not the pivot, right?
A mesher + pointcache, which yields the same vertex transformations but with different pivot produced different animation of the particles, and moving the pivot on that also changed the particles, so there’s something odd going on.
Yep, reproduced it here, smells like a bug to me.
We usually work with cached reference objects with a pivot at 0,0,0 and never add an object offset matrix (moved pivot), so we never saw this in the past, but I am pretty sure it should not happen.
Seems to get worse the further away the pivot is, so it might be some precision issue, too.