Three Play Animation

You can load a rigged character into a Three scene with WASThreeLoadModel and it'll stand there in its bind pose, frozen mid-T, which is not a great look. WASThreePlayAnimation is the node that takes the animation clips already saved inside the model file and actually plays them - the walk cycle runs, the character walks. It's how the Three family handles animation without you hand-keying a single frame.

How it works

Animation clips live inside model files. Three Play Animation reads the clips a .glb, .gltf, .dae or .fbx carries - the formats that rigged characters come in. An .obj, .stl, .ply or .3mf carries no clips, so there's nothing to play, which is worth knowing before you spend an hour wondering why a static mesh won't move.

The clip field picks which clip to play, by name ("Walk") or by number ("0"). Leave it empty and it plays the first one. Give it a name the model doesn't have and you get an error that helpfully names every clip the file does carry.

The inputs that matter

The interesting part is units, which controls how a clip maps onto time:

• per second - the clip runs at its authored speed. 1.0 speed is the natural rate, 0.5 is half, negative runs it backwards.
• per capture - one pass of the clip is spread across the whole render, so a walk cycle fills the batch whatever its frame count. No arithmetic: your walk fills the clip end to end.
• per timeline - spread across Three App's loop_seconds instead, and the render then captures a window out of that longer loop. This is how you take a part of a long walk rather than refitting the whole thing.

offset is seconds into the clip the run starts at. The killer use for it is crowds: give three copies offsets of 0.0, 0.4 and 0.8 and a line of clones doesn't march in step. loop sets the tail behavior - repeat starts again, once holds the last pose, ping pong runs it backwards and forwards.

A subtle thing to appreciate

The pose is worked out from the moment alone - the node evaluates the animation at a point in time rather than accumulating motion frame by frame. So a frame drawn twice comes out identical both times, which makes renders deterministic and re-rendering a mid-animation frame safe. That's the kind of property that saves you from hair-pulling in video work.

Where it fits

The output is an animated object that replaces the loaded model in the group. Character flow: Three Load Model → Three Play Animation → Three Group, alongside your lights, then scene → Three App → Three Render. The pack ships a three-skinned-model.json workflow demonstrating exactly this.

Install

WASThreePlayAnimation ships with WAS Node Suite v3. Install via ComfyUI Manager (search WAS Node Suite v3) or:

cd ComfyUI/custom_nodes
git clone https://github.com/WASasquatch/was-node-suite-comfyui.git

Restart after. Requires ComfyUI 0.14.0+ and Python 3.10+. If the node's absent from Add Node, check features.threejs in <ComfyUI user dir>/was-node-suite/config.yaml (on by default in current releases) and restart.