/* global variables */
var onImages;
var offImages;

function sfHover() {
	var sfEls = document.getElementById("nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}

function preloadImages() {
	if (document.images) {
		onImages = new Array();
		onImages[0] = new Image(150, 43);
		onImages[0].src = "_images/_navigation/AboutUs_on.png";
		onImages[1] = new Image(150, 43);
		onImages[1].src = "_images/_navigation/Services_on.png";
		onImages[2] = new Image(150, 43);
		onImages[2].src = "_images/_navigation/Projects_on.png";
		onImages[3] = new Image(150, 43);
		onImages[3].src = "_images/_navigation/Opportunities_on.png";
		onImages[4] = new Image(150, 43);
		onImages[4].src = "_images/_navigation/ContactUs_on.png";
		
		offImages = new Array();
		offImages[0] = new Image(150, 43);
		offImages[0].src = "_images/_navigation/AboutUs_off.png";
		offImages[1] = new Image(150, 43);
		offImages[1].src = "_images/_navigation/Services_off.png";
		offImages[2] = new Image(150, 43);
		offImages[2].src = "_images/_navigation/Projects_off.png";
		offImages[3] = new Image(150, 43);
		offImages[3].src = "_images/_navigation/Opportunities_off.png";
		offImages[4] = new Image(150, 43);
		offImages[4].src = "_images/_navigation/ContactUs_off.png";
    }
}

function swapImage(imageID, state) {
	if (document.images) {
		var image = document.getElementById('navImg' + imageID);
		
		image.src = eval(state + "Images[" + imageID + "].src");
	}
}