// event handling
  document.onmousemove = mouseMoveHandler;
  document.onmousedown = mouseDownHandler;
  document.onmouseup = mouseUpHandler;
  if (ns) document.captureEvents(Event.MOUSEMOVE | Event.MOUSEDOWN | Event.MOUSEUP);
  
  /*
   * The mouse handlers in this document must call the modulator's handlers.
   * To be able to use a mouse modulator and to do your own stuff.
   */
  function mouseMoveHandler(e) {
  
   // calls move handler of the mouse modulator
   myMouseModulator.move(e);
  
   /*
   // other stuff, e.g.
   if (ns || ie) {
     mouseX = (ns) ? e.pageX : event.x;
     mouseY = (ns) ? e.pageY : event.y;
   }
   */
  
   return !ie;
  }
    
  function mouseDownHandler(e) {
   // calls down handler of the mouse modulator
   myMouseModulator.down(e);
  }
  
  function mouseUpHandler(e) {
   // calls up handler of the mouse modulator
   myMouseModulator.up(e);
  }