2025-01-30 Animation & Rigging module meeting

The meeting was on 2025-01-30T17:00:00Z. It is open for everybody interested to join the video call (link below).

Present: Andy Beers, Christoph Lendenfeld, David Woolf, Drew Medina, Drew Medina, Felipe G, Jeremy Bot, Nate Rupsis, Sybren Stüvel

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

Links

Opening

  • Please raise your hand when you don’t understand things for any reason. The purpose of these meetings is collaboration. It is absolutely fine to ask for explanations.
  • There are no recordings of the meeting. This way everybody is free to say or show anything they want.

Since the Last Meeting / Announcements

Landed

Names are from the Git log. This list is limited to functional improvements & bugfixes.

Blender

Technical Documentation

User Manual

Ongoing Work

  • High Prio bugs:
  • Christoph:
  • Nathan:
    • Nathan’s weekly report
    • Continuing work on Winter of Quality tasks for Slotted Actions.
    • Created design task: #133725: Anim: switching assigned action on multiple data-blocks together
      • Looking for feedback & discussion!
      • Module agrees, this is nice and we need both approaches.
      • Sybren: doesn’t want a popup every time an Action is switched to ask “what do you want”?
      • Sybren: if Alt-click works, then also “Copy to Selected” should work.
      • Drew: Where would the dialog show up with all the options?
      • Sybren: that would likely be the “Redo Panel”. The Properties editor doesn’t have this Redo Panel though, so that makes this a very good question…
      • Christoph: in the Properties editor, I wouldn’t expect Alt+click to switch all the users of the Action. It should work the same as other “Copy to Selected” in that area. Like for Mesh properties it can be about “selected vertices”, and it would be weird if this particular option were about selected objects instead.
      • Sybren: maybe the “Extras” menu like we have next to lists-of-things would be the right place then.
      • Sybren: The ‘Action Based’ operator could use its own little pop-up where you select an Action.
      • Sybren: we also have to think about how this relates to library overrides, and linked (and thus immutable) data.
  • Sybren:
    • Sybren’s weekly report
    • Copy-Paste: refactor has landed (#133497), will work on actually supporting slots early next week.
    • ‘Wildcarding’ of typed & untyped slots (#133653)
    • #133727: Anim: emit liboverride on slot handle when action is changed
    • Little request from Pablo Fournier: new mode for Insert Key operator in Dope Sheet / Action Editor / Graph Editor, which inserts keys just like in the 3D Viewport.
      • Question: what about objects whose animation data you do not see in that editor? For example, having two objects selected would key them both, but if they have separate Actions the Action Editor only shows one of them. Should that still key the 2nd object?
      • Sybren: proposes to only insert keys for data-blocks that are visible in the animation editor right now.
      • Christoph: that can be hard, because not-animated things are not shown in the dope sheet.
      • Sybren: might be a nice query for the replacement animation filtering system: “which things are considered for display here?” rather than “what is animated now?”.
  • Animator meeting at Blender HQ, with Rik Schutte, Hjalti Hjálmarsson, and Pablo Fournier:
    • Rik filed three weight painting bugs, all got closed by the triagers:
    • It’s clear that Weight Paint mode is an orphan (and has too many step-parents to raise it properly), falling between the Sculpt, Paint & Texture module and the Animation & Rigging module.
    • Sybren will take it up with Dalai.
    • Rik: Blending between NLA strips ignores the ‘Stepped’ modifier, and blending on 1s.
      • Nate: Blending is kind of broken to begin with. I wouldn’t be surprised if this was never implemented. Create an issue for it, Nate might have time to look into it.
    • Rik: Blending between NLA strips sometimes also blends to rest pose in the middle. Nathan will go and look.
      • Sybren: might be a misunderstanding. Having the bottom layer at 50% and the top layer at “Replace” mode 50% will not create a 50/50 blend between the two. Rather it will take 50% between rest pose & the bottom, and then replace that for 50% with the top.
    • Hjalti: Bone Custom Shape transform properties are not covered by the X-Mirror option. So tweaking those still has to happen on each side manually.
      • Sybren: checks how other properties behave. In Armature Edit mode, dragging the bone head X property with X-mirror enabled will mirror. But in Pose mode, dragging the bone rotation X with X-mirror enabled does NOT mirror. That’s a bug.
      • Rik: More tools could use the X-mirror option. Like the Breakdowner, applying/blending pose assets, etc.
      • Sybren: would love to build an animation tool framework where it’s easy to build tools that change properties/transforms, and then the framewould would look at X-mirror and apply things mirrored as well. This should also blur the lines between Object and Bone/Armature rigs, and make those tools available in Object & Pose mode alike.
    • Hjalti: The Shift+G operator (Select Groups, with lotsa options) in Object mode is much richer than in Pose mode. Would be nice low-hanging fruit to implement this for Pose mode as well.

Next Meeting

The next meeting will be on 2025-02-06T17:00:00Z. Again it will be open for everybody who’s interested. The provisionary meeting agenda will be updated before the meeting.

3 Likes

it would be great if Vertex Groups could be put into folders / collections, and then normalization etc. could be applied per folder / collection.

Yes, please.

Attributes/vertex groups/shape keys desperately need some kind of file system rather than a flat list.

Before I learned Python, I tried to rig a hair mesh from an asset store, and the number of vertex groups required made it the biggest PITA ever.

Now I’m working on an importer and I use attributes to cache data that doesn’t exist natively in Blender. And I hate the fact that they exist in a flat list with native Blender attributes. And you know when vertex groups and shape keys become attributes too, it’s going to be so much worse.

Please, reach out to the UI team and make this a priority.

2 Likes

I know this is a bit far-fetched. In Mantis, he still has separate bones for FK and IK, whereas in Cascadeur, Daz3d, or even a Blender addon called Ragdoll Dynamics, it is possible to use the same bones to switch between FK and IK. That makes using imported poses or animations much more easily. Do you think that is possible in the official implementation of Rigging Nodes? I know that is very distant in the future, but I am curious.

1 Like

The Rigging Nodes system that I have in mind right now is basically a clone of Unreal Engine’s Control Rig (we have Epic’s permission to copy ideas & designs, just not actual code). Basically the setup would be a simple Armature for the FK bones, and then a control rig with its own controls & shapes on top of that. What the actual interaction is going to look like is, as you say, still distant future.

7 Likes

I admit I never really understood how to use Unreal Engine, so I don’t know if Rigging Nodes would solve my current problem or inconvenience. Right now, when I am importing poses or animations from other softwares, they would always be applied to the FK bones in Rigify. But the poses in, for example, the fingers cannot be transferred to the other posing method Rigify is using for fingers. That makes it hard to adjust poses or animations after importing them. I think Unreal Engine has an operator called “Bake to Control Rig” that kinda helps with that?

Are you using or have you tried the Expy addon (GitHub - pKrime/Expy-Kit: Blending different Character Rigs together) which I think has an option to do such Baking.

Asking the obvious question as someone that’s never used Unreal, how close is the new Mantis node rigger to those ideas and designs? I mean no point in re-creating the wheel, if someone has already half built it in Blender.

1 Like

Given the presentation Mantis Rigging Nodes is a modular metarig system, ie it is used to generate rigs from “prefabs” (node groups), but it does not do the actual evaluation (=constraints, relationships between bones, animation), which is what I think Sybren was referring to : a replacement to Blender’s current constraint system basically. Think of Mantis as playing more or less the same role as Rigify.

By the way what is up with that ? any chance you can elaborate a little ?

1 Like

Yup, that’s right.

By the way what is up with that ? any chance you can elaborate a little ?

Epic Games are cool. There isn’t much further to elaborate on, beyond what I said already.

3 Likes

Such care is usually given to respect proprietary programs’ IP and to distance Blender from them, that I was surprised taking inspiration so liberally would be possible, without the backing of some written agreement. That’s it. Otherwise I am happy that big players are so collaborative.

1 Like

Given Epics history with blender it’s not too surprising tbh.

“Open tools, libraries and platforms are critical to the future of the digital content ecosystem,” said Tim Sweeney, founder and CEO of Epic Games. “Blender is an enduring resource within the artistic community, and we aim to ensure its advancement to the benefit of all creators.”
Epic Games supports Blender Foundation with $1.2 million Epic MegaGrant — blender.org

Also It’s even in their own interest to get people used to workflows inside unreal, so aspiring game devs will prefer it over other engines as it may feel more familiar.

1 Like

Don’t assume that that doesn’t exist, just because one developer did not mention this in one particular thread on one discussion forum (i.e. me, here). It may, it may not, I don’t know. I just know what we can and shouldn’t do right now.

1 Like