var px = 50;//mehr=schneller

function moveObject(event)
{
  var delta = 0;
  
  if (!event) event = window.event;
  // normalize the delta
  if (event.wheelDelta)
  {
    // IE & Opera
   delta = event.wheelDelta / 120;
  }
  else if (event.detail) // W3C
  {
    delta = -event.detail / 3;
  }

  d = document.getElementById('thumbnails');
  var currPos = d.scrollLeft;
  
  //calculating the next position of the object
  currPos=parseInt(currPos)+(delta*10);

  step = (delta<0?-1:1) * px;
  
  //moving the position of the object
  document.getElementById('thumbnails').scrollLeft = currPos + step;

  
	if(d.scrollLeft > px) 
		document.getElementById('arrow_l').style.visibility = "visible"
	else 
		document.getElementById('arrow_l').style.visibility = "hidden"

	if(d.scrollLeft == d.scrollWidth - d.offsetWidth) 
		document.getElementById('arrow').style.visibility = "hidden"
	else 
		document.getElementById('arrow').style.visibility = "visible"
  
}


window.onload = function()
{
  //adding the event listerner for Mozilla
  if(window.addEventListener) document.addEventListener('DOMMouseScroll', moveObject, false);
  //for IE/OPERA etc
  document.onmousewheel = moveObject;
  
  setDiv();
}