// preload images of button bar
function preloadMain()
{
	if (document.images)
	{
	  var Path = "img/menu_";
	  var Ext  = ".jpg";

	  img_animal = new Image();
	  img_animal.src = Path + "animal" + Ext;
	  img_animal_hi = new Image();
	  img_animal_hi.src = Path + "animal_hi" + Ext;

	  img_links = new Image();
	  img_links.src = Path + "links" + Ext;
	  img_links_hi = new Image();
	  img_links_hi.src = Path + "links_hi" + Ext;

	  img_stones = new Image();
	  img_stones.src = Path + "stones" + Ext;
	  img_stones_hi = new Image();
	  img_stones_hi.src = Path + "stones_hi" + Ext;

	  img_wisdom = new Image();
	  img_wisdom.src = Path + "wisdom" + Ext;
	  img_wisdom_hi = new Image();
	  img_wisdom_hi.src = Path + "wisdom_hi" + Ext;

	  img_products = new Image();
	  img_products.src = Path + "products" + Ext;
	  img_products_hi = new Image();
	  img_products_hi.src = Path + "products_hi" + Ext;

	  img_jp = new Image();
	  img_jp.src = Path + "jp" + Ext;
	  img_jp_hi = new Image();
	  img_jp_hi.src = Path + "jp_hi" + Ext;
	}
}

// load highlighted image
function imgOver(imgName)
{
  if (document.images)
    document[imgName].src = eval(imgName + "_hi.src");
}

// load standard image
function imgOut(imgName)
{
  if (document.images)
    document[imgName].src = eval(imgName + ".src");
}