function change_visible(div_id, img_id, img_plus, img_minus) {
	
	if (document.getElementById(div_id).style.display == "none") {
		document.getElementById(div_id).style.display = "block";
		document.getElementById(img_id).src = img_minus;
	} else {
		document.getElementById(div_id).style.display = "none";
		document.getElementById(img_id).src = img_plus;
	}
	
} // change_visible

function swapImgRestore() {
	
	var i, x, a = document.sr;
	for (i = 0; a && i < a.length && (x = a[i]) && x.oSrc; i ++)
		x.src=x.oSrc;
	
} // swapImgRestore

function preloadImages() {
	
	var d = document;
	if (d.images) {
		if (!d.p) d.p = new Array();
		var i, j = d.p.length, a = preloadImages.arguments;
		for(i=0; i<a.length; i++)
			if (a[i].indexOf("#") != 0) {
				d.p[j] = new Image;
				d.p[j ++].src = a[i];
			}
	}
	
} // preloadImages

function findObj(n, d) {
	
	var p, i, x;
	if (!d) d = document;
	if ((p = n.indexOf("?")) > 0 && parent.frames.length) {
		d = parent.frames[n.substring(p + 1)].document;
		n = n.substring(0, p);
	}
	if (!(x = d[n]) && d.all)
		x=d.all[n];
	for (i = 0; !x && i < d.forms.length; i ++)
		x = d.forms[i][n];
	for (i = 0; !x && d.layers && i<d.layers.length; i ++)
		x = findObj(n, d.layers[i].document);
	if (!x && d.getElementById)
		x = d.getElementById(n);
		return x;
	
} // findObj

function swapImage() {
	var i, j = 0, x, a = swapImage.arguments;
	document.sr = new Array;
	for (i = 0; i < (a.length - 2); i += 3)
		if ((x = findObj(a[i])) != null) {
			document.sr[j ++] = x;
			if (!x.oSrc) x.oSrc = x.src;
			x.src = a[i+2];
		}
} // swapImage