Nine ways an action never plays
The misspelled node name is the only one that prints a warning. The rest are silent.
A clip stores keyframes, a mixer plays them on a model, and an action is one playing copy you can pause, loop and crossfade. You drive a real animated fox and learn the nine reasons an action never plays.
Change the code and press Run (Ctrl+Enter). Predict what will happen first, then break it on purpose and read what changes. Your edits are saved and match the lesson page.
Ready for more? This phase has 6 hands-on exercises with automatic checks.
Practice questions
Write the code in the editor, run it, then open the model answer to compare.
Play the Fox's Survey clip once and hold the last pose.
Write a function switchTo(next) that crossfades the current action to next over 0.3 s, and call it for Walk and Run.
Explain it without notes
Name the four objects between an animation file and a moving model, and say what each does.
A walk cycle plays on the Fox but the Run action does nothing after crossFadeTo. Give two likely causes.
Console
Nothing logged yet.Expected console output
play() and update() turns: -0.250
forgot play() turns: 0.000
forgot mixer.update() turns: 0.000
THREE.PropertyBinding: No target node found for track: cranck.rotation[z].
track names a node that is not there turns: 0.000
setEffectiveWeight(0) turns: 0.000
paused = true turns: 0.000
timeScale = 0 turns: 0.000
LoopOnce, finished, then play() again turns: 0.000
LoopOnce, finished, reset().play() turns: -0.250