Function useAnimationTimer

src/ink/hooks/use-interval.ts:13–34

(intervalMs: number)

 * frame index) from the shared clock.
 */
export function useAnimationTimer(intervalMs: number): number {
  const clock = useContext(ClockContext)
  const [time, setTime] = useState(() => clock?.now() ?? 0)

  useEffect(() => {
    if (!clock) return

    let lastUpdate = clock.now()

    const onChange = (): void => {
      const now = clock.now()
      if (now - lastUpdate >= intervalMs) {
        lastUpdate = now
        setTime(now)
      }
    }

    return clock.subscribe(onChange, false)
  }, [clock, intervalMs])

  return time
}

/**
 * Interval hook backed by the shared Clock.