// preload and creat rollover method for home page
var what=[], how=[], who=[], why=[];
var tag=['IMG', 'IMG_off', 'Txt'];
for (var i=0; i<3 ; i++) {
	what[i]=new Image();
	how[i]=new Image();
	who[i]=new Image();
	why[i]=new Image();
	what[i].src="/media/images/home_what" + tag[i] + ".gif";
	how[i].src="/media/images/home_how" + tag[i] + ".gif";
	who[i].src="/media/images/home_who" + tag[i] + ".gif";
	why[i].src="/media/images/home_why" + tag[i] + ".gif";
}
	defaultText=new Image();
	defaultText.src="/media/images/home_defaultTxt.gif";

function doRollover(o,mode) {

	var whichID = o.parentNode.id;
	var textDisplay = document.getElementById("textDisplay");
		
	if (mode == "on"){
		switch(whichID) {
			case "img1":
				o.src=what[0].src;
				textDisplay.src=what[2].src;
				break;
			case "img2":
				o.src=how[0].src;
				textDisplay.src=how[2].src;
				break;
			case "img3":
				o.src=who[0].src;
				textDisplay.src=who[2].src;
				break;
			case "img4":
				o.src=why[0].src;
				textDisplay.src=why[2].src;
				break;
			default:
				textDisplay.src=what[2].src;
				break;
		}
	} else {
		switch(whichID) {
			case "img1":
				o.src=what[1].src;
				textDisplay.src=defaultText.src;
				break;
			case "img2":
				o.src=how[1].src;
				textDisplay.src=defaultText.src;
				break;
			case "img3":
				o.src=who[1].src;
				textDisplay.src=defaultText.src;
				break;
			case "img4":
				o.src=why[1].src;
				textDisplay.src=defaultText.src;
				break;
			default:
				textDisplay.src=what[2].src;
				textDisplay.src=defaultText.src;
				break;
		} //switch
	} //else
} // function