var interval = 3000;
var random_display = 0;
var imageDir = "images/";
var imageNum = 0;

imageArray = new Array();
imageArray[imageNum++] = new imageItem(imageDir + "cl1.gif");
imageArray[imageNum++] = new imageItem(imageDir + "cl2.gif");
imageArray[imageNum++] = new imageItem(imageDir + "cl3.gif");

function imageItem(image_location) {
		this.image_item = new Image();
		this.image_item.src = image_location;
	}
	function get_ImageItemLocation(imageObj) {
		return(imageObj.image_item.src)
	}
function imageItem(image_location) {
		this.image_item = new Image();
		this.image_item.src = image_location;
	}
	function get_ImageItemLocation(imageObj) {
		return(imageObj.image_item.src)
	}
function getNextImage() {
		if (random_display) {
			imageNum = randNum(0, totalImages-1);
		}
		else {
			imageNum = (imageNum+1) % totalImages;
		}
}
	function getPrevImage() {
		imageNum = (imageNum-1) % totalImages;
		var new_image = get_ImageItemLocation(imageArray[imageNum]);
		return(new_image);
	}
function prevImage(place) {
		var new_image = getPrevImage();
		document[place].src = new_image;
	}
function switchImage(place) {
	var new_image = getNextImage();
	document[place].src = new_image;
	var recur_call = "switchImage('"+place+"')";
	timerID = setTimeout(recur_call, interval);
	}