function changeImage(direction) {
    which_image_loaded += direction;
    if (which_image_loaded < 0)
        which_image_loaded = NUMBER_OF_IMAGES - 1;
    if (which_image_loaded == NUMBER_OF_IMAGES)
        which_image_loaded = 0;
    if (document.images)
        document.myimage.src = ImageNames[which_image_loaded];
}


function checkBrowser(){
	this.ver=navigator.appVersion
	this.dom=document.getElementById?1:0
	this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
	this.ie4=(document.all && !this.dom)?1:0;
	this.ns5=(this.dom && parseInt(this.ver) >= 5) ?1:0;
	this.ns4=(document.layers && !this.dom)?1:0;
	this.bw=(this.ie5 || this.ie4 || this.ns4 || this.ns5)
	return this
}
bw=new checkBrowser()

function showHide(div,nest){
	obj=bw.dom?document.getElementById(div).style:bw.ie4?document.all[div].style:bw.ns4?nest?document[nest].document[div]:document[div]:0;
	if(obj.visibility=='visible' || obj.visibility=='show') obj.visibility='hidden'
	else obj.visibility='visible'
}

function show(div,nest){
	obj=bw.dom?document.getElementById(div).style:bw.ie4?document.all[div].style:bw.ns4?nest?document[nest].document[div]:document[div]:0;
	obj.visibility='visible'
}

function hide(div,nest){
	obj=bw.dom?document.getElementById(div).style:bw.ie4?document.all[div].style:bw.ns4?nest?document[nest].document[div]:document[div]:0;
	obj.visibility='hidden'
}


pic = new Image();
pic1 = new Image();
pic1.src = "images/medewerkers/pauldiederen_off.jpg";
pic2 = new Image();
pic2.src = "images/medewerkers/bertdirrix_off.jpg";

pijl1 = new Image();
pijl1.src = "images/pijlGR.gif";

function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		knop1_over = newImage("images/p_stedenbouw-on.gif");
		knop2_over = newImage("images/p_utiliteitsbouw-on.gif");
		knop3_over = newImage("images/p_woningbouw-on.gif");
		knop4_over = newImage("images/p_villa-on.gif");
		knop5_over = newImage("images/p_interieur-on.gif");
		preloadFlag = true;
	}
}

last_image = null;

function doClick(btn)
{
  if (last_image != null)
  {
    last_image.className = "outside";
  }
  btn.className = "inside";
  last_image = btn;
}

last_over = null;

function toggle(btn)
{
  if (btn.className == "outside")
  {
    btn.className = "inside";
  }
  else
  {
    if (last_image != btn)
    {
      btn.className = "outside";
    }
  }
}