/*
NOTE:  -The filenames of the TABBED images MUST end in either _on.gif or _off.gif  DO NOT USE ANY OTHER 
 NAMING CONVENTIONS OR FILE FORMATS!!!!!!!!!!!
*/
	function preload_images(){
		if(document.images){
		home_off = new Image();
		home_on = new Image();
		artists_off= new Image();
		artists_on = new Image();
		aboutus_off= new Image();
		aboutus_on= new Image();
		infopics_off= new Image();
		infopics_on= new Image();
		contact_off = new Image();
		contact_on = new Image();
		press_off = new Image();
		press_on = new Image();
		merch_off = new Image();
		merch_on = new Image();
		
		
		path="images/nav/";
		home_off = path + "home_off.gif";
		home_on = path + "home_on.gif";
		artists_off= path + "artists_off.gif";
		artists_on = path + "artists_on.gif";
		aboutus_off= path + "aboutus_off.gif";
		aboutus_on= path + "aboutus_on.gif";
		infopics_off= path + "infopics_off.gif";
		infopics_on= path + "infopics_on.gif";
		contact_off = path + "contact_off.gif";
		contact_on = path + "contact_on.gif";
		press_off = path + "press_off.gif";
		press_on = path + "press_on.gif";
		merch_off = path + "merch_off.gif";
		merch_on = path + "merch_on.gif";
	
		}
	}
	
	/* main image swapping function.  if the current images is not on the "hover" state, rename the src of image to include an "on.gif" or "on" state.*/
	
	function getNextImg(src) {
		var path = src.substr(0, src.lastIndexOf("/") + 1);
		var current = src.substr(src.lastIndexOf("/") + 1);
		var src = current.split("_")[0];
		var current_state = current.split("_")[1];
		var next_state = (current_state.indexOf("on") == -1) ? "on.gif" : "off.gif";
		var next = path + src + "_" + next_state;
		return next;
	}
	
	function swap(){	
		var next = getNextImg(this.src)
		this.src = next;
	}
	
	function addSwap() {
		var tabs = document.getElementById(tabsname);
	

		var imgs = tabs.getElementsByTagName("img");
		for(var i = 0; i < imgs.length; i++) {
			if(imgs[i].parentNode.id == "current_page") {
				imgs[i].src = getNextImg(imgs[i].src);
				continue;
			}
			imgs[i].onmouseover = swap;
			imgs[i].onmouseout = swap;
		}
	}
	

	function addLoadEvent(func) {
		var oldload = window.onload;
		if(typeof window.onload == "function")
			window.onload = function() {
				oldload();
				func();
			}
		else
			window.onload = func;
	}
		
	addLoadEvent(preload_images);
	addLoadEvent(addSwap);