Authored motion

A Basis avatar has no animator layers, so animation that plays on its own is rebuilt as BasisAuthoredMotion, a component that replays baked motion. A tail that sways, ears that twitch, an accessory that turns: on VRChat these are FX layers with nothing steering them.

Two kinds

Motion the avatar has. A layer with no parameter steering it, whose state holds a clip that turns transforms over time. It plays from the moment the avatar loads.

Motion a menu switches on. A Vixxy control stores a value per choice, not a curve, so a toggle whose clip animates cannot hold it. The animation becomes a motion of its own and the control enables and disables the component, which Vixxy permits for this type. It starts in the state the control's default choice puts it in.

A clip authored to loop keeps looping while the control holds it on. One that was not plays once each time it is switched on.

What is written

Each becomes one movement of kind Sequence, holding a BasisMotionClip: the clip's rotations sampled at 60 frames a second, one row per bone it turns. Rotations are recorded as they land on the bone rather than as the curve states them, so a clip replays correctly whatever rest pose the avatar has.

The baked clip is written into a Watari Motion folder beside the animation it came from, at a path derived from the clip's name, so converting a second time replaces it rather than leaving a copy behind.

note

An undo does not remove the baked clip. It is a project asset, not a component, so the components disappear and the clip stays on disk.

What does not carry across

• Movement and scaling. A baked Basis motion clip holds rotation only. A clip that also moves or scales something keeps the turning and reports the rest as motion.rotationOnly.
• Anything else a clip animates over time. A toggle whose clip moves, scales or drives something other than rotation is reported and left alone.