rAF tutorial: advanced time tracking

raf-performance-mark.js

const trackTime = id => {
  const [entry] = performance.getEntriesByName(id);
  if (!entry) {
    performance.mark(id);
    return 0;
  }
  return performance.now() - entry.startTime;
};
                                                                                                                                                                                                                                                                                           
const getProgress = ({duration, id}) => {
  const progress = Math.min(trackTime(id) / duration, 1);
  if (progress == 1) performance.clearMarks(id);
  return progress;
};

const tick = () => {
  const progress = getProgress(animation);
  if (progress < 1) requestAnimationFrame(tick);
};

const animation = {
  duration: 500,
  id: requestAnimationFrame(tick)
};