Interface DimensionAnimationState

Whether animation is currently playing

Target FPS for animation

Loop behavior (once, loop, bounce)

Current animation direction

When the next playback tick is due (a performance.now() timestamp). Advanced by one period per tick, so the cadence holds the target rate instead of drifting by a vsync per tick; resynced after a stall.

Frame counter for FPS measurement

Time of last FPS measurement

Measured actual FPS (may differ from target)

Playback "detail": how deep every frame's additive ladder is loaded while this dimension plays (and scrubs). A number pins that many rungs (Infinity = the whole ladder); 'auto' pins each ladder at the first rung whose cumulative energy reaches config.dimensionAnimation.playback.autoEnergyThreshold (an unstamped ladder stays time-budgeted); null streams whatever is resident within the tick ("Fast"). Threaded to the progressive loaders as ViewState.ladderDepth.

Explicit per-tick step size in dimension units; null = Auto (continuous dims derive the increment from fps + the range-traversal time, discrete dims use their authored step). Also consumed by the [ / ] keyboard navigation. Deliberately NOT consumed by the slider wheel/drag — hand stepping stays on the dimension's own base step.