var rotateDelay = 3;
var rotateInterval = false; 
var topImage = new Array();
var revealImage = 1;
var zIndex = 3;

$(document).ready(function() {
	// Init
	topImage[1] = 1;	
	topImage[2] = 4;	
	topImage[3] = 7;	

	// Randomize image rotation
	rotateInterval = setInterval("rotateImage()",rotateDelay * 1000);
});

function rotateImage() {
	col = rand(3);

	curImage = topImage[col];
	curImage++;
	
	if(curImage > (col * 3)) {
		if(col == 1) {
			curImage = 1;
		} else if(col == 2) {
			curImage = 4;
		} else if(col == 3) {
			curImage = 7;
		}
	}
	
	// Bring image to front
	zIndex++;
	$('#image-image'+curImage+' img').hide().css('zIndex',zIndex).fadeIn(300);	
	
	topImage[col] = curImage;
}

function rand(n) {
	return Math.floor(Math.random() * n + 1);
}