observeCue

Subscribe to threshold crossings. Returns stop().

const stop = observeCue(motionValue, CUE, {
  initialSync: true,
  emitExitsOnStop: false,
  bus: myBus,
  onEnter: (key, ctx) => {},
  onExit: (key, ctx) => {},
});

stop(); // unsubscribe

The ctx object provides:

value — current MotionValue value
progress — normalized 0–1
wasActive — whether the threshold was active before this crossing
direction — "ascending" | "descending" | "none"
velocity — current velocity

Options

Option	Default	Description
`initialSync`	`true`	Fire `onEnter` for already-active thresholds on subscribe
`emitExitsOnStop`	`false`	Fire `onExit` for active thresholds when `stop()` is called
`bus`	—	Fan-out `CueBus` for multiple subscribers