A throttle function using requestAnimationFrame instead of timers

throttle.js

var requestAnimationFrame = window.requestAnimationFrame;

function throttle(callback) {
  var tickRequested = false;

  function tick() {
    callback();
    tickRequested = false;
  }

  return function() {
    if (tickRequested) {
      console.warn('Dropping frame');
      return;
    }

    tickRequested = true;
    requestAnimationFrame(tick);
  };
}