Adapter for this track's value type — also the §17 track-type discriminant (see the module header's table).
OptionalinIncoming tangent per key, required by — and only used by — "hermite".
Same length as times. Entry 0 is never read (no segment ends at the first
key) but is required so the arrays stay index-parallel. See AnimationTrackOptions.outTangents for the units.
OptionalinterpolationInterpolation mode (§17). Defaults to "linear".
OptionaloutOutgoing tangent per key, required by — and only used by — "hermite".
Same length as times. The last entry is never read (no segment starts at
the last key).
Tangents are derivatives with respect to clip time, i.e. value units
per second, matching the tangents "cubic" derives for itself. A segment
uses the left key's out tangent and the right key's in tangent.
Dot-separated property path relative to the mixer's target, resolved by the
mixer and never by the track ("transform.position", "opacity"). Must be
non-empty; its resolvability is checked when it is bound, not here.
Keyframe times in seconds, clip-local, strictly increasing and finite. At least one. Copied.
Keyframe values, one per entry of AnimationTrackOptions.times. The array is copied; the values themselves are held by reference and must not be mutated afterwards.
Construction inputs for AnimationTrack.