var loaded = false;



function rollImgs() {

  if (document.images) {

    newImage('aboutOn', '../images/menu_about_us_o.gif');

    newImage('aboutOff', '../images/menu_about_us.gif');  

    newImage('whatsOn', '../images/menu_whats_new_o.gif');

    newImage('whatsOff', '../images/menu_whats_new.gif');

    newImage('locationsOn', '../images/menu_locations_o.gif');

    newImage('locationsOff', '../images/menu_locations.gif');

    newImage('productsOn', '../images/menu_products_o.gif');

    newImage('productsOff', '../images/menu_products.gif');

    newImage('promosOn', '../images/menu_promotions_o.gif');

    newImage('promosOff', '../images/menu_promotions.gif');

    newImage('eyecareOn', '../images/menu_eye_care_o.gif');

    newImage('eyecareOff', '../images/menu_eye_care.gif');

    newImage('linksOn', '../images/menu_links_o.gif');

    newImage('linksOff', '../images/menu_links.gif');

    newImage('contactOn', '../images/contact_us_o.gif');

    newImage('contactOff', '../images/contact_us.gif');

    loaded = true; 

  }

}



function newImage(name, fileName){

	window[name] = new Image();

	window[name].src = fileName;

}



function chgImg(imgField,newImg) {

	if (document.images && loaded) {

		document[imgField].src= eval(newImg+'.src');

	}

}