// this function allows us to set variables by passing them in as values in the query string
// by default it looks for the query string after the occurrence of '.html?' in URL of the current document
// but these values can be passed in as parameters
function parseQuery(loc,key) {
	if (loc == null) loc = document.location.href;
	if (key == null) key = '?';
	if (loc.indexOf(key) > -1) {
		query = loc.substring(loc.indexOf(key)+key.length,loc.length);
		args = query.split('\&');
		for (i=0; i<args.length; i++) {
			chunk = args[i];
			eval(chunk.split('=')[0] + " = '" + chunk.split('=')[1] + "'");
		}
	}
}

function newImage(arg) {
	rslt = new Image();
	rslt.src = arg;
	return rslt;
}

function dw(msg) {
	document.write(msg);
}

function randomNum(start,end) {
	var range = end - start + 1;
	var n = Math.floor(Math.random() * (range)) + start;
	return n.toString();
}

function imgOn(which) {
	if (which && onImgs) {
		if (onImgs[which]) {
			document.images[which].src = onImgs[which].src;
		}
	}
}

function imgOver(which) {
	if (which && overImgs) {
		if (overImgs[which] && which != navcurrent) {
			document.images[which].src = overImgs[which].src;
		}
	}
}

function imgOff(which) {
	if (which && offImgs) {
		if (offImgs[which] && which != navcurrent) {
			document.images[which].src = offImgs[which].src;
		}
	}
}

function setCurrent(which) {
	if (which) {
		if (document.images[which]) {
			imgOver(which);
			document.images[which].className = "navcurrent";
			navcurrent = which;
		}
	}
}


function show(which) {
	document.getElementById(which).style.visibility = "visible";
}

function hide(which) {
	document.getElementById(which).style.visibility = "hidden";
}

function showdisplay(which) {
	document.getElementById(which).style.display = "inline";
}

function hidedisplay(which) {
	document.getElementById(which).style.display = "none";
}

function platformCSS() {
	var isMac = (navigator.userAgent.indexOf("Mac") > -1);
	var macCSS = "/lib/styles-mac.css";
	var pcCSS = "/lib/styles-pc.css";

	document.write('<link rel="stylesheet" type="text/css" href="'+ (isMac ? macCSS : pcCSS) +'">')
}

//platformCSS();
var offImgs = new Array();
var overImgs = new Array();
var onImgs = new Array();