function setupSwapImg() {

	var triggers = getElementsByClassName(document,"a","swapimg");
	for (var i =0; i< triggers.length; i++) {
		var mainimg = document.getElementById("mainimg");
		if (mainimg) {
			triggers[i].triggers = triggers;
			triggers[i].mainimg = mainimg;
			// setup linked list
			if (triggers[i+1]) {
				triggers[i].nextTrigger = triggers[i+1];
			} else {
				triggers[i].nextTrigger = triggers[0];				
			}
			triggers[i].onclick = function() {			
				for (var j=0; j<this.triggers.length; j++) {
					this.triggers[j].className = "swapimg";
				}
				this.preload();
				this.className = "swapimg current";								
				this.mainimg.currentTrigger = this;
				this.mainimg.src = this.href;
				this.mainimg.setAttribute("alt",this.getAttribute("title"));
				this.mainimg.setAttribute("title",this.getAttribute("title"));				
				return false;
			}
			triggers[i].preload = function() {
				// preload the next image
				if (!this.nextImg) {
					this.nextImg = document.createElement("img");
					this.nextImg.src = this.nextTrigger.href;
				}				
			}
			mainimg.style.cursor = "pointer";
			mainimg.onclick = function() {				
				this.currentTrigger.nextTrigger.onclick();
			}
		}
	}
	if (triggers[0] && triggers[1]) {
		mainimg.currentTrigger = triggers[0];
		triggers[0].className = "swapimg current";		
		triggers[0].preload();
	}
}

function getElementsByClassName(oElm, strTagName, strClassName){
    var arrElements = (strTagName == "*" && document.all)? document.all : oElm.getElementsByTagName(strTagName);
    var arrReturnElements = new Array();
    strClassName = strClassName.replace(/\-/g, "\\-");
    var oRegExp = new RegExp("(^|\\s)" + strClassName + "(\\s|$)");
    var oElement;
    for(var i=0; i<arrElements.length; i++){
        oElement = arrElements[i];      
        if(oRegExp.test(oElement.className)){
            arrReturnElements.push(oElement);
        }   
    }
    return (arrReturnElements)
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

function preloadNav() {
	var nav_images = new Array("about","arts","branding","contact","corporate","home","news","retail");
	for (var i=0; i<nav_images.length; i++) {
		var img = document.createElement("img");
		img.src = "img/nav_on/"+nav_images[i]+".gif";
	}	
}

addLoadEvent(preloadNav);
addLoadEvent(setupSwapImg);