function displayEmptyImage(el) {
	if (el)
		el.src = '/images/dot_clear.gif';
}

function toggleReference(id) {
	var el = document.getElementById('reference_'+id);
	if (!el)
		return false;
	
	if (el.style.display == 'block')
		el.style.display = 'none';
	else
	 	el.style.display = 'block';
}

function createCorners(el) {
	if (!el) return;
	
	var className = 'top';
	var start = '<p class='+className+'1></p><p class='+className+'2></p><p class='+className+'3></p><p class='+className+'4></p><div>'; 
	var end = '</div><p class='+className+'4></p><p class='+className+'3></p><p class='+className+'2></p><p class='+className+'1></p>';
	el.innerHTML = start + el.innerHTML +  end;
}

function initCorners() {
	var mainsite = document.getElementById('mainsite');
	if (!mainsite)
		return;
	
    var elements = mainsite.getElementsByTagName("DIV");
    for (var i = 0;i < elements.length;i++){
        if (elements[i].className.indexOf(" ") >= 0){
            var classes = elements[i].className.split(" ");
            for (var j = 0;j < classes.length;j++) {
                if (classes[j] == 'bannerGeel' || classes[j] == 'bannerRood' || classes[j] == 'containerBoekbutton')
					createCorners(elements[i]);
            }
        }
        else if (elements[i].className == 'bannerGeel' || elements[i].className == 'bannerRood' || elements[i].className == 'containerBoekbutton')
			createCorners(elements[i]);
    }
}