Function tick

examples/sampling/main.ts:214–224

()

  let rafId: number | null = null;
  let lastKey = '';
  const tick = (): void => {
    const z = chart.getZoomRange();
    const key = z
      ? `${z.start.toFixed(3)}:${z.end.toFixed(3)}:${controls.mode}:${controls.threshold}`
      : `null:${controls.mode}:${controls.threshold}`;
    if (key !== lastKey) {
      lastKey = key;
      updateReadouts(data.length, xMax, controls, z);
    }
    rafId = requestAnimationFrame(tick);
  };

  updateReadouts(data.length, xMax, controls, chart.getZoomRange());
  rafId = requestAnimationFrame(tick);