// functie die window.onload verbetert
function addLoadEvent(func) {
	var oldonload = window.onload;
	if (typeof window.onload != 'function') {
		window.onload = function() { func; }
	} else {
		window.onload = function() {
			if (oldonload) {
			oldonload();
			}
			func();
		}
	}
}

//var url = 'http://www.omega-webdesign.nl/tmp/foto.jpg'; 

addLoadEvent(laadAchtergrond(url));

function laadAchtergrond(url) {
	ImgSRC = new Image();
	ImgSRC.onload = function(){
	
		var divp1 = document.getElementById('achtergrond');
		if(divp1) {
			setOpacity(divp1, 0);
		
			divp1.style.visibility = 'visible';
			fadeIn('achtergrond',0);
		}
	}
	ImgSRC.src = url;
}


function setOpacity(obj, opacity) {
  opacity = (opacity == 100)?99.999:opacity;
  
  // IE/Win
  obj.style.filter = "alpha(opacity:"+opacity+")";
  
  // Safari<1.2, Konqueror
  obj.style.KHTMLOpacity = opacity/100;
  
  // Older Mozilla and Firefox
  obj.style.MozOpacity = opacity/100;
  
  // Safari 1.2, newer Firefox and Mozilla, CSS3
  obj.style.opacity = opacity/100;
}

function fadeIn(objId,opacity) {
  if (document.getElementById) {
    obj = document.getElementById(objId);
    if (opacity <= 100) {
      setOpacity(obj, opacity);
      opacity += 10;
      window.setTimeout("fadeIn('"+objId+"',"+opacity+")", 100);
    }
  }
}