function CalculateHeight()
{
	if(window.innerHeight)
		return(window.innerHeight);
	if(document.documentElement.clientHeight)
	{
		if(document.documentElement.clientHeight>0)
			return(document.documentElement.clientHeight);
	}
	if(document.body.clientHeight)
		return(document.body.clientHeight);
	return(800);
}