2023-06-01 Animation & Rigging module meeting

The meeting will be on 2023-06-01T16:00:00Z. It is open for everybody interested to join on Google Meet (link below).

Present: Armin Halac, Brad Clark, Christoph Lendenfeld, Daniel Salazar, Denys Hsu, Eduardo Rubio, Jason Schleifer, Marion Stalke, Nate Rupsis, Nathan Vegdahl, Nitin Rawat, Paolo Amadini, Paul Thuriot, Sybren Stüvel

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


Since the Last Meeting / Announcements

  • New face: Paolo Amadini, interested in helping out with development.
    • Nate: a good way to get into the development workflow could also be to help updating the manual, to get familiar with Git, pull requests, reviews, etc.
  • Blender 4.0 development has started.
  • Tomorrow: Code Quality Day


Blender 3.6:

Blender 4.0:

Short-term goals / Ongoing Work

Patch Review & Decision Time

  • #107173: Refactor: Bidirectionality on Graph Editor Sliders #107173
    • Christoph proposes a change to slider operators. Currently many of them work in the 0-100% range, with 50% as a neutral value. He proposes change such sliders to a 0% neutral value and go from -100% to 100%.
    • Decision: module agrees this is a good change, will land in 4.0
  • #108257: Fix #108229: Wider tolerance shuffling NLA strips
    • Nate: fix makes sense at first glance, will look into it further soon.
  • #108134: Fix #32022, #43188, #100373, Armature modifier - Preserve volume + Scale
    • Nathan likes to get a consensus if we should merge it once it’s ready, given that it’s only a partial fix.
    • Fixes only uniform scaling, where both bones in a bendy joint have the same scale factor.
    • Brad: this is not an issue to just Blender, other tools also patch various issues. Two other variations of solutions are described in Dual Quaternion Skinning with scale - Rodolphe Vaillant's homepage, but that document also links to patents…
    • Sybren: use this to address other issues with dual quaternions (like non-uniform scaling, shear, etc.)? Nathan: only if we have time, let’s land this first.
    • Nate: is this a breaking change? As it changes mesh deformation? This should be documented as such.
    • Decision: can land in 4.0 as it does make the dual quaternion skinning a lot more useful.
    • Marion: would this address other issues with scale for game animation export? Brad: not really, it’s a separate thing.
    • Daniel: can, in the future, dual quaternions be managed by weight groups, so that it’s only used for part of the mesh and can be blended?
    • Nathan: that’s one of the use cases for the ‘Multi Modifier’ checkbox of the ‘Armature’ modifier. So that’s already in Blender.
  • #108296: Regression: Cannot Overwrite Pose in Pose Library
    • Brad: updating poses is under-documented, is a usability issue.
    • Module agrees, even updating an existing pose in the current blend file is hard.
    • Sybren: this should be revisisted then.
    • Brad: sliding & blending poses seems to be broken too. Christoph can help with this.
  • Nate: Adi Sage, in Blender Chat, proposes some alternative keymap for switching between animation editors in a consistent way.
    • Brad: there currently is no way to use a hotkey to switch to the NLA.
    • Sybren: could be a good Right Click Select proposal.
    • Nathan: never uses Shift-Fx keys for this, as it requires taking his hand off the mouse. How about having a pie menu for this?
    • Module: definitely room for improvement here.
  • #107950: WIP: VSE Experiment in Mouse Cursor and Transform Status Feedback
    • Brad: this requires further discussion on right-click-select vs. left-click-select interaction models, and their effect on selection vs. manipulating strips vs. manipulating the playhead.

Next Meeting

The next meeting will be on Thursday 2023-06-08T16:00:00Z. 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.