function Viewport() { 
	if( typeof( window.innerWidth ) == 'number' ) {
		//Non-IE
		this.windowX = window.innerWidth;
		this.windowY = window.innerHeight;

	} else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
		//IE 6+ in 'standards compliant mode'
		this.windowX = document.documentElement.clientWidth;
		this.windowY = document.documentElement.clientHeight;

	} else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
		//IE 4 compatible
		this.windowX = document.body.clientWidth;
		this.windowY = document.body.clientHeight;

	}

	//this.windowX = (document.documentElement && document.documentElement.clientWidth) || window.innerWidth || self.innerWidth || document.body.clientWidth; 
	//this.windowY = (document.documentElement && document.documentElement.clientHeight) || window.innerHeight || self.innerHeight || document.body.clientHeight; 

	this.scrollX = (document.documentElement && document.documentElement.scrollLeft) || window.pageXOffset || self.pageXOffset || document.body.scrollLeft; 
	this.scrollY = (document.documentElement && document.documentElement.scrollTop) || window.pageYOffset || self.pageYOffset || document.body.scrollTop; 
	this.pageX = (document.documentElement && document.documentElement.scrollWidth) ? document.documentElement.scrollWidth : (document.body.scrollWidth > document.body.offsetWidth) ? document.body.scrollWidth : document.body.offsetWidth; 
	this.pageY = (document.documentElement && document.documentElement.scrollHeight) ? document.documentElement.scrollHeight : (document.body.scrollHeight > document.body.offsetHeight) ? document.body.scrollHeight : document.body.offsetHeight;
}