https://ukparachuting.co.uk/wp-content/themes/brooklyn/js/greensock/AnimationFrame.js?ver=1.0

1// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
2// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating
3
4// requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel
5
6// MIT license
7
8(function() {
9    "use strict";
10    var lastTime = 0;
11    var vendors = ['ms', 'moz', 'webkit', 'o'];
12    for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
13        window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
14        window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame']
15            || window[vendors[x]+'CancelRequestAnimationFrame'];
16    }
17
18    if (!window.requestAnimationFrame)
19        window.requestAnimationFrame = function(callback, element) {
20            var currTime = new Date().getTime();
21            var timeToCall = Math.max(0, 16 - (currTime - lastTime));
22            var id = window.setTimeout(function() { callback(currTime + timeToCall); },
23                timeToCall);
24            lastTime = currTime + timeToCall;
25            return id;
26        };
27
28    if (!window.cancelAnimationFrame)
29        window.cancelAnimationFrame = function(id) {
30            clearTimeout(id);
31        };
32}());