var W3CDOM = (document.createElement && document.getElementsByTagName);

var mouseOvers = new Array();
var mouseOuts = new Array();
 var MenuUnderlines = new Array();
 var menupics = new Array(); //array to hold loaded menu image objects


window.onload = init;

function init()
{

 MenuUnderlines = returnmenupics();
 loadallmenupics();


	if (!W3CDOM) return;
	var nav = document.getElementById('menu');
	var imgs = nav.getElementsByTagName('img');
	for (var i=0;i<imgs.length;i++)
	{
		imgs[i].onmouseover = mouseGoesOver;
		imgs[i].onmouseout = mouseGoesOut;
		var suffix = imgs[i].src.substring(imgs[i].src.lastIndexOf('.'));
		mouseOuts[i] = new Image();
		mouseOuts[i].src = imgs[i].src;
		mouseOvers[i] = new Image();
		mouseOvers[i].src = imgs[i].src.substring(0,imgs[i].src.lastIndexOf('.')) + "_underline" + suffix;
		imgs[i].number = i;
	}
}

function mouseGoesOver()
{
	this.src = mouseOvers[this.number].src;
}

function mouseGoesOut()
{
	this.src = mouseOuts[this.number].src;
}

function loadallmenupics(){ //load all the menupics in MenuUnderlines array
   for(var i=1; MenuUnderlines[i]; i++){
     loadmenupic(i);
   }
}

function loadmenupic(num){
   menupics[num] = new Image();
   menupics[num].src = MenuUnderlines[num];
}

function returnmenupics() {
   var MenuUnderlines = new Array();
   MenuUnderlines[1]  = 'imgs2/marticles_underline.gif';
   MenuUnderlines[2]  = 'imgs2/mbio_underline.gif';
   MenuUnderlines[3]  = 'imgs2/mclipart_underline.gif';
   MenuUnderlines[4]  = 'imgs2/mcontact_underline.gif';
   MenuUnderlines[5]  = 'imgs2/merikswish_underline.gif';
   MenuUnderlines[6]  = 'imgs2/mgallery_underline.gif';
   MenuUnderlines[7]  = 'imgs2/mhome_underline.gif';
   MenuUnderlines[8]  = 'imgs2/mlinks_underline.gif';
   MenuUnderlines[9]  = 'imgs2/mnewsletter_underline.gif';
   MenuUnderlines[10]  = 'imgs2/mphonelessons_underline.gif';
   MenuUnderlines[11]  = 'imgs2/mprograms_underline.gif';
   MenuUnderlines[12]  = 'imgs2/mtechnique_underline.gif';
   MenuUnderlines[13]  = 'imgs2/mtestimonials_underline.gif';
   return MenuUnderlines;
}