Real-Time 3D Graphics with WebGL 2 - Second Edition

Setting up the Animation Timer

The render and onFrame functions look exactly the same as in the previous examples:

function onFrame() {  elapsedTime = (new Date).getTime() - initialTime;  if (elapsedTime < animationRate) return;  let steps = Math.floor(elapsedTime / animationRate);  while (steps > 0) {    animate();    steps -= 1;  }  initialTime = (new Date).getTime();}function render() {  initialTime = (new Date).getTime();  setInterval(onFrame, animationRate / 1000);}