if (!Date.now)
Date.now = function() { return new Date().getTime(); };
(function() {
'use strict';
var vendors = ['webkit', 'moz'];
for (var i = 0; i < vendors.length && !window.requestAnimationFrame; ++i) {
var vp = vendors[i];
window.requestAnimationFrame = window[vp+'RequestAnimationFrame'];
window.cancelAnimationFrame = (window[vp+'CancelAnimationFrame']
|| window[vp+'CancelRequestAnimationFrame']);
}
if (/iP(ad|hone|od).*OS 6/.test(window.navigator.userAgent) // iOS6 is buggy
|| !window.requestAnimationFrame || !window.cancelAnimationFrame) {
var lastTime = 0;
window.requestAnimationFrame = function(callback) {
var now = Date.now();
var nextTime = Math.max(lastTime + 16, now);
return setTimeout(function() { callback(lastTime = nextTime); },
nextTime - now);
};
window.cancelAnimationFrame = clearTimeout;
}
}());
