

<!--
/**
 * function onmousewheel,
 * onmousewheel(element:Object [, callback:Function]):Void
 * @param Object  window, document or DOM.element to use with callback
 * @param Function callback function with element scope (.call(...)) and delta wheel value as single parameter
 * @return Void
 */
function onmousewheel(element, callback) {
  
 // @author Andrea Giammarchi  [http://www.devpro.it/]
 // @license MIT     [http://www.opensource.org/licenses/mit-license.php]
 // @credits Adomas Paltanavicius   [http://adomas.org/javascript-mouse-wheel/]
 
 function __onwheel(event) {
  var delta = 0;
  if(event.wheelDelta) {
   delta = event.wheelDelta / 120;
   if(window.opera)
    delta = -delta;
  }
  else if(event.detail)
   delta = -event.detail / 3;
  if(delta)
   callback.call(element, delta);
  if(event.preventDefault)
   event.preventDefault();
  event.returnValue = false;
  return false;
 };
 
 if(element.addEventListener && !window.opera)
  element.addEventListener("DOMMouseScroll", __onwheel, false);
 else
  element.onmousewheel = (function(base){return function(evt){
   if(!evt) evt = window.event;
   if(base) base.call(element, evt);
   return __onwheel(evt);
  }})(element.onmousewheel);
};
//-->