var preloadFlag = false;

/* preloads image */
function makeImage (url) {
	if (document.images) {
		img = new Image();
		img.src = url;
		return img;
	}
}

/* builds image array */
var swaps = new Array ();
function makeSwaps () {
	if (document.images) {
		with (makeSwaps) {
			var state = arguments[0], path = arguments[1], ext = arguments[2];
			for (var i = 3; i < arguments.length; i += 3) {
				var slice = arguments[i], init = arguments[i+1], swap = arguments[i+2];
				var init_url = path + init + ext;
				var swap_url = path + swap + ext;
				if (!swaps[slice]) {
					swaps[slice] = new Array ();
					swaps[slice]['init'] = init_url;
				}
				swaps[slice][state] = makeImage (swap_url);
			}
		}
	}
}

/* swaps single slice, shows status bar message */
function changeImages (slice, state, msg, div) {
	if (!msg) { msg = ''; } /* undef = '' */
	window.status = msg;
	if (document.images && (preloadFlag)) {
		var type = (slice.indexOf('bullet') == -1) ? slice : 'bullet';
		if (div && B.NN) {
//			alert ("Slice: " + slice + " State: " + state + " Msg: " + msg + " Div: " + div);
			document[div].document.images[slice].src = (state) ? swaps[type][state].src : swaps[type]['init'];
		} else {
			document[slice].src = (state) ? swaps[type][state].src : swaps[type]['init'];
		}
	}
}