function getPageWidth()
{
	var viewportwidth;

	if(typeof window.innerWidth != 'undefined')
	{
		viewportwidth = window.innerWidth;
	}
	else if(typeof document.documentElement != 'undefined' && typeof document.documentElement.clientWidth != 'undefined' && document.documentElement.clientWidth != 0)
	{
		viewportwidth = document.documentElement.clientWidth;
	}
	else
	{
		viewportwidth = document.getElementsByTagName('body')[0].clientWidth;
	}

	return viewportwidth;
}

function getPageHeight()
{
	var viewportheight;

	if(typeof window.innerHeight != 'undefined')
	{
		viewportheight = window.innerHeight;
	}
	else if(typeof document.documentElement != 'undefined' && typeof document.documentElement.clientHeight != 'undefined' && document.documentElement.clientHeight != 0)
	{
		viewportheight = document.documentElement.clientHeight;
	}
	else
	{
		viewportheight = document.getElementsByTagName('body')[0].clientHeight;
	}

	return viewportheight;
}

function isDefined(variable) {
	return (typeof(window[variable]) == "undefined")?false:true;
}

function isObject(mixed_var) {
	if(mixed_var instanceof Array) {
		return false;
	} else {
		return (mixed_var !== null) && (typeof( mixed_var ) == 'object');
	}
}

(function($) {
	var cache = [];
		// Arguments are image paths relative to the current page.
	$.preLoadImages = function() {
		var args_len = arguments.length;
		for (var i = args_len; i--;) {
			var cacheImage = document.createElement('img');
			cacheImage.src = arguments[i];
			cache.push(cacheImage);
		}
	}
})(jQuery);