// JavaScript Document
var interval = 3000;
var random_display = 1;
var imageDir = "nav/";
var imageNum = 0;
	imageArray = new Array();
	imageArray[imageNum++] = new imageItem(imageDir + "pic01.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic02.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic03.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic04.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic05.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic06.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic07.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic08.jpg");
	imageArray[imageNum++] = new imageItem(imageDir + "pic09.jpg");
var totalImages = imageArray.length; 

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 randNum(x, y) {
		var range = y - x + 1;
		return Math.floor(Math.random() * range) + x;
	}

function getNextImage() {
		if (random_display) {
			imageNum = randNum(0, totalImages-1);
		}
		else {
			imageNum = (imageNum+1) % totalImages;
		}
 	
var new_image = get_ImageItemLocation(imageArray[imageNum]);
	return(new_image);
	}

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);
        }