Clock

1/** Wall-clock with pause/step support. All systems read `clock.t` and `clock.dt`. */
2export const clock = {
3  t: 0,
4  dt: 1 / 60,
5  frame: 0,
6  paused: false,
7  stepRequested: false,
8  _last: performance.now() / 1000,
9  tick(now = performance.now() / 1000) {
10    const raw = Math.min(0.05, Math.max(0, now - this._last));
11    this._last = now;
12    if (this.paused && !this.stepRequested) {
13      this.dt = 0;
14      return;
15    }
16    this.stepRequested = false;
17    this.dt = this.paused ? 1 / 60 : raw;
18    this.t += this.dt;
19    this.frame++;
20  },
21};