RequestAnimationFrame Polyfill

RequestAnimationFrame.js

// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

// requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel

// MIT license

!window.requestAnimationFrame && (window.requestAnimationFrame = null)
!window.cancelAnimationFrame && (window.cancelAnimationFrame = null)

!function() {
    var lastTime = 0,
        vendors = ['ms', 'moz', 'webkit', 'o']

    if (!cancelAnimationFrame) {
        for (var i = 0; i < vendors.length && !requestAnimationFrame; ++i) {
            requestAnimationFrame = window[vendors[i] + 'RequestAnimationFrame']

            cancelAnimationFrame =
                window[vendors[i] + 'CancelAnimationFrame'] || window[vendors[i] + 'CancelRequestAnimationFrame']
        }
    }

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

            var id = setTimeout(function () {
                callback(currTime + timeToCall)
            }, timeToCall)

            lastTime = currTime + timeToCall

            return id
        };
    }

    if (!cancelAnimationFrame) {
        cancelAnimationFrame = function(id) {
            clearTimeout(id)
        };
    }
}()