if (document.images) {
   var fullglass = new Image();
   fullglass.src = "/images/FullGlass.gif";
   var emptyglass = new Image();
   emptyglass.src = "/images/EmptyGlass.gif";
}

function swap_glass(state, doc) {
	// var returndoc = doc ;
	// alert(doc);
	if (state) {
		document["glass" + doc].src = emptyglass.src;
	} else {
		document["glass" + doc].src = fullglass.src;
	}
}