AnimationFrame; ++x) {
          window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
          window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame']
            || window[vendors[x]+'CancelRequestAnimationFrame'];
        }

        if (!window.requestAnimationFrame)
          window.requestAnimationFrame = function(callback, element) {
            var currTime = new Date().getTime();
            var timeToCall = Math.max(0, 16 - (currTime - lastTime));
            v