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_home_o.gif');

		newImage('contactOff', 'images/contact_us_home.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');

	}

}