“Render Animation” doesn't refresh bone constraint to rendering frame in 2.8

Question

I have a character that switches from armature control to a rag doll controlled by the physics system using bone constraints. It works fine when playing in the viewport or when rendering a single frame, but does not work when rendering the whole animation.

I found this article that seemed to have the same issues. The response was:

"This is a known issue in our current depsgraph, there is a workaround for it though - enable Extra Object Update and/or Extra Data Update for armature and ant mesh, in Object buttons, Relations Extra panel.

Anyway, not a bug, rather a known TODO for our future new depsgraph. ;)"

But I don't see those options in 2.8. Anyone have any suggestions?

Thanks!

Viewport Video

Rendered Video

Rendered Still

Blend File

Answer 1

I was having a similar problem. My issue was I had one bone with a Damped Track constraint pointed at a another bone which had it's own Damped Track constraint pointed right back at the first bone. It should have still worked since the tracking constraint didn't affect the location of either bone's head, but... it apparently confused Blender anyway. Ultimately, in order to fix the problem I had to create 2 more bones with no constraints in the same locations of the original 2 bones. I could then have the original 2 bones point at those un-constrained bones. In other words, having a constrained bone relying on another constrained bone can cause problems.