window.size = function()
{
	var w = 0;
	var h = 0;

	//IE
	if(!window.innerWidth)
	{
		//strict mode
		if(!(document.documentElement.clientWidth == 0))
		{
			w = document.documentElement.clientWidth;
			h = document.documentElement.clientHeight;
		}
		//quirks mode
		else
		{
			w = document.body.clientWidth;
			h = document.body.clientHeight;
		}
	}
	//w3c
	else
	{
		w = window.innerWidth;
		h = window.innerHeight;
	}
	return {width:w,height:h};
}

window.center = function () {
	var hWnd = (arguments[0] != null) ? arguments[0] : { width: 0, height: 0 };

	var _x = 0;
	var _y = 0;
	var offsetX = 0;
	var offsetY = 0;

	//IE
	if (!window.pageYOffset) {
		//strict mode
		if (!(document.documentElement.scrollTop == 0)) {
			offsetY = document.documentElement.scrollTop;
			offsetX = document.documentElement.scrollLeft;
		}
		//quirks mode
		else {
			offsetY = document.body.scrollTop;
			offsetX = document.body.scrollLeft;
		}
	}
	//w3c
	else {
		offsetX = window.pageXOffset;
		offsetY = window.pageYOffset;
	}

	_x = ((this.size().width - hWnd.width) / 2) + offsetX;
	_y = ((this.size().height - hWnd.height) / 2) + offsetY;

	return { x: _x, y: _y };
}