function tab_change (tab, selected, base) {
	// don't change current tab
	if (tab == selected_tab) {
		if (selected_tab_up) {
			return;	
		}
	}

	var add = "";
	var myclass = "";
	if (selected) {
		add = "sel";
		myclass = "current";
	}

	if (base.length > 0) {
		document.getElementById("tab_left" + tab).style.background="url("+base+"img/tabs/greytab" + add + "_left.png)";
		document.getElementById("tab_mid" + tab).style.background="url("+base+"img/tabs/greytab" + add + "_mid.png)";
		document.getElementById("tab_right" + tab).style.background="url("+base+"img/tabs/greytab" + add + "_right.png)";
	} else {
		document.getElementById("tab_left" + tab).style.background="url(/img/tabs/greytab" + add + "_left.png)";
		document.getElementById("tab_mid" + tab).style.background="url(/img/tabs/greytab" + add + "_mid.png)";
		document.getElementById("tab_right" + tab).style.background="url(/img/tabs/greytab" + add + "_right.png)";
	}
	document.getElementById("tablink" + tab).className = myclass;
}

function setPhoto(src) {
	document.getElementById('hoofdFoto').src = src.replace( '_52', '_350' );
}

function swap_kamer_photo(id)
{
	current_image += 1;
	if (current_image > plaatjes[id].length-1) {
		current_image = 0;
	}
	document.getElementById('kamer_foto' + id).src = plaatjes[id][current_image].src;
}

function clearText(thefield){
	if (thefield.defaultValue==thefield.value) {
		thefield.value = ""
	}
}

function check_zoeken (form) {
	if (form.zoek_plaats_hidden.value.length == 0) {
		form.zoek_plaats_hidden.value = form.zoek_plaats.value;
	}
}