function Animation(context){
	var nativeRequest, nativeCancel;
	this.context = context;
	this.vendors = ['ms', 'moz', 'webkit', 'o'];
	this.performance = this.performance();
	this.startTime = +new Date();
	this.lastTime = +new Date();
	this.now = this.performance.now||this.now;
	for(var x=0; x<this.vendors.length; x++){
		nativeRequest = window[this.vendors[x]+'RequestAnimationFrame'];
		nativeCancel = window[this.vendors[x]+'CancelAnimationFrame']||window[this.vendors[x]+'CancelRequestAnimationFrame'];
	}
	this.request = nativeRequest||this.request;
	this.cancel = nativeCancel||this.cancel;
}

Animation.prototype.request = function(callback){
	var currentTime, delay, _ = this;
	currentTime = +new Date();
	delay = 16 + _.lastTime - currentTime;
	delay = delay < 0 ? 0 : delay;
	_.lastTime = currentTime;
	return window.setTimeout(function(){
		_.lastTime = +new Date();
		callback(performance.now());
	}, delay);
};

Animation.prototype.cancel = function(id){
	window.clearTimeout(id);
};

Animation.prototype.performance = function(){
	return window.performance && window.performance.now ? window.performance : {};
};

Animation.prototype.now = function(id){
	return +new Date() - this.startTime;
};