function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages(lang) {
	if (document.images) {
		menu_difflang_over = newImage(lang+"/images/menu_difflang.gif");
		menu_hkscm_over = newImage(lang+"/images/menu_hkscm.gif");
		menu_intro_over = newImage(lang+"/images/menu_intro.gif");
		menu_activities_over = newImage(lang+"/images/menu_activities.gif");
		menu_map_over = newImage(lang+"/images/menu_map.gif");
		menu_tickets_over = newImage(lang+"/images/menu_tickets.gif");
		menu_highlights_over = newImage(lang+"/images/menu_highlights.gif");
		menu_sites_over = newImage(lang+"/images/menu_sites.gif");
		preloadFlag = true;
	}
}

function preloadImages_index(lang){
	if (document.images) {
		home_btn_difflang_over = newImage(lang+"/images/home_btn_difflang.gif");
		home_btn_hkscm_over = newImage(lang+"/images/home_btn_hkscm.gif");
		home_btn_intro_over = newImage(lang+"/images/home_btn_intro.gif");
		home_btn_activities_over = newImage(lang+"/images/home_btn_activities.gif");
		home_btn_map_over = newImage(lang+"/images/home_btn_map.gif");
		home_btn_tickets_over = newImage(lang+"/images/home_btn_tickets.gif");
		home_btn_highlights_over = newImage(lang+"/images/home_btn_highlights.gif");
		home_btn_sites_over = newImage(lang+"/images/home_btn_sites.gif");
		preloadFlag = true;
	}
}