var currentSlide;

function displaySlide(containerId,slideId,headerId,headerId2){
	hideHeaders(containerId);
	swapSlide(slideId);
	if (headerId) displayInline(headerId);
	if (headerId2) displayInline(headerId2);
}

function swapSlide(id){
	if (currentSlide) hideSlide(currentSlide);
	showSlide(id);
	currentSlide=id;
}

function showSlide(id){
	changeVisibility(id,'visible');
}

function hideSlide(id){
	changeVisibility(id,'hidden');
}

function changeVisibility(id,value){
	var div=document.getElementById(id);
	if (div && typeof div.style!='undefined') div.style.visibility=value;
}


function displayInline(id){
	document.getElementById(id).style.display='inline';
}

function displayNone(id){
	document.getElementById(id).style.display='none';
}

function hideHeaders(id){
	hideElements(id,'h2');
	hideElements(id,'h3');
}

function hideElements(id,tag){
	var elements=document.getElementById(id).getElementsByTagName(tag);
	for(var i=0;i<elements.length;i++){
		displayNone(elements[i].id);
	}
}

function updateTab(tab,x,y,img){
	if (typeof tab=='string') tab=document.getElementById(tab).getElementsByTagName('a')[0];
	tab.style.background='url('+img+') no-repeat '+x+'px '+y+'px';
}