2023-05-25 Animation & Rigging module meeting

The meeting was on 2023-05-25T16:00:00Z. It is open for everybody interested to join on Google Meet (link below).

Present: Christoph Lendenfeld, Demeter Dzadik, Denys Hsu, Jason Schleifer, MohammadHossein Jamshidi, Nate Rupsis, Nathan Vegdahl (hosting), Omer Almadani, Paul Thuriot, Sybren Stüvel (partial)

People present are referred to by first name for brevity. Others are referred to by full name.


Since the Last Meeting / Announcements


Short-term goals / Ongoing Work

Patch Review & Decision Time

  • Hotkey Hotness:
    • Tab for NLA ‘upper stack’ vs. ‘full stack’.
      • Neither Sybren for Brad are at the meeting, and they seem like the key parties. So recommend they talk to each other to come to a decision.
    • Blender 3.6 introduces the D hotkey for the slider operators. Since we already know this will change in 4.0, we maybe want to reevaluate what we do with 3.6.
      • Since the change in the graph editor’s ‘Key’ menu is also already in 3.6, there is no release with that ‘D’ hotkey anyway.
      • Decision: Merge it for 3.6.
  • #82831: Inclusive bounds for VertexWeightEdit?
    • Decision: Let’s do it for 4.0. Add versioning code so that that the threshold is adjusted to have the same behavior.

Help Needed

Next Meeting

The next meeting will be on Thursday 2023-06-01T16:00:00Z. Again it will be open for everybody who’s interested. The provisionary meeting agenda will be linked in the #animation-module channel before the meeting.


For breaking changes in 4.0, I’d be interested to know if anyone is using the iTaSC solver. As I understand it, it was never better than the Standard solver for animation, and for robotics it was never really picked up and is outdated now.

If the animation project is going to make significant changes to rigging, I think it will be better to have just one IK solver to use and improve, rather than dealing with both implementations and the ikplugin abstraction.


I’ve never seen it used in production. From my experience the standard IK solver provides all the necessary control for character rigging (although fiddly in places, such as the way the user controls stretchiness and stiffness of individual bones in an IK chain), is very similar to IK solvers in other software, and is simpler to set up than iTaSC. My two cents would be iTaSC can be removed.

However, in the future and in the context of nodal simulations (=not character animation), having a stateful IK solver would probably be valuable.


Yes, really stateful IK should not be a feature of the IK solver itself. Like simulation nodes with geometry, you want to be able to use arbitrary nodes to update the pose from one frame to the next, with an IK solver node just being one possibility.