function menuLoadImages(menuOffImageDir, menuOnImageDir, menuImageNames, menuImageExt)
{
  var i, name;

  if (document.images)
  {
    for (i = 0; i < menuImageNames.length; i++)
    {
      name = menuImageNames[i];
      this.menuItemSelected[name] = false;
      this.menuItemImages[name] = new Array();
      this.menuItemImages[name].onImage = new Image;
      this.menuItemImages[name].onImage.src = menuOnImageDir + name + '.' + menuImageExt;
      this.menuItemImages[name].offImage = new Image;
      this.menuItemImages[name].offImage.src = menuOffImageDir + name + '.' + menuImageExt;
    }
  }
}


function menuItemOn(name)
{
  if (document.images && this.menuItemSelected != name)
    document.images[name].src = this.menuItemImages[name].onImage.src;
  return true;  
}


function menuItemOff(name)
{
  if (document.images && this.menuItemSelected != name)
    document.images[name].src = this.menuItemImages[name].offImage.src;
  return true;  
}


function menuItemSelOn(name)
{
  if (this.menuItemSelected != name && this.menuItemSelected != '' )
    document.images[this.menuItemSelected].src = this.menuItemImages[this.menuItemSelected].offImage.src;
  if (document.images && name != '')
    document.images[name].src = this.menuItemImages[name].onImage.src;
  this.menuItemSelected = name;
  return true;  
}


function menuRollOver(menuOffImageDir, menuOnImageDir, menuImageNames, menuImageExt)
{
  this.menuItemSelected = ''; 
  this.menuItemImages = new Array(menuImageNames.length);
  this.menuItemOn = menuItemOn;
  this.menuItemOff = menuItemOff;
  this.menuLoadImages = menuLoadImages;
  this.menuItemSelOn = menuItemSelOn;
  this.menuLoadImages(menuOffImageDir, menuOnImageDir, menuImageNames, menuImageExt);
}


function mapLoadImages(mapOnImageDir, mapImageNames, mapImageExt)
{
  var i, name;

  for (i = 0; i < mapImageNames.length; i++)
  {
    name = mapImageNames[i];
    this.mapImages[name] = new Image;
    this.mapImages[name].src = mapOnImageDir + name + '.' + mapImageExt;
  }
}


function mapItemOn(name)
{
  if (document.images)
    document.images[this.mapDefImageName].src = this.mapImages[name].src;
  return true;  
}


function mapItemOff()
{
  if (document.images)
    document.images[this.mapDefImageName].src = this.mapImages[this.mapDefImageName].src;
  return true;  
}


function mapRollOver(mapDefaultImageName, mapOnImageDir, mapImageNames, mapImageExt)
{
  this.mapDefImageName = mapDefaultImageName;
  this.mapImages = new Array(mapImageNames.length);
  this.mapItemOn = mapItemOn;
  this.mapItemOff = mapItemOff;
  this.mapLoadImages = mapLoadImages;
  this.mapLoadImages(mapOnImageDir, mapImageNames, mapImageExt);
}