var swapTimeout=8000;
function swap(){
	img=document.getElementById('image1');
	if(x>anzahl)
		x=0;
	img.src=images[x].src;
	x++;
	if (doswap) {
		window.setTimeout('swap()', swapTimeout);
		
		// set opacity to all elements
		var marked=Array();
		marked=getElementsByClassName('ausstellung');
		for (var i=0; i<marked.length; i++)
			addClassName(marked[i], 'has-opacity');
		
		// now remove opacity from currently displayed element
		var elem=null;
		elem=document.getElementById('ausstellung-'+x);
		if (elem!=null)
			removeClassName(elem, 'has-opacity');
	}
	
}
function setSwap(wert){
	doswap=wert;
	if(wert==true)
		swap();
}

// get all elements with className and return them as array
function getElementsByClassName(className){
	if (className=='') 
		return;
		
	var	node = document.getElementsByTagName('body')[0];
	
	var arr=Array();

	className = "\\b" + className + "\\b"; // word boundaries!
	
	var children = node.getElementsByTagName('*');
	for (var i = 0; i < children.length; i++) {
		if (children[i] && children[i].className) {
			if (children[i].className.search(className) != -1) {
				arr.push(children[i]);
			}
		}
	}
	return arr;
}

// remove className from class attributes of node
function removeClassName(node, className) {
	if (className=='')
		return;
	var classString=node.className;
	var classes=Array;
	classes=classString.split(/ /);

	var newClassString='';
	for (var i=0; i<classes.length; i++) {
		if ( classes[i]!=className)				
			newClassString+=classes[i]+" ";
	}
	node.className=newClassString;
}

// add className to class attribute of node
function addClassName(node, className) {
	if (node=='' || className=='' || !node.className)
		return;
		
	var classString=node.className;
	classString+=" "+className;
	node.className=classString;
}