update(fps = 60) {
    const delta = (1000 / fps) >> 0;

    if (!this.time) {
      this.time = TWEEN.now();
      TWEEN.now = () => this.time;
    } else {
      this.time += delta;
    }

    TWEEN.update(this.time);
    forEach(this.cbs, cb => cb(this.time, delta));
    this.delta = delta;
  }
TimelineUpdate update function
@param {number} fps - Frame rate
@public