// 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

(function() {
    var lasttime = 0;
    var vendors = ['ms', 'moz', 'webkit', 'o'];
    for(var x = 0; x < vendors.length && !window.requestanimationframe; ++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));
            var id = window.settimeout(function() { callback(currtime + timetocall); },
                timetocall);
            lasttime = currtime + timetocall;
            return id;
        };

    if (!window.cancelanimationframe)
        window.cancelanimationframe = function(id) {
            cleartimeout(id);
        };
}());