I asked this earlier but never got it solved. I got a hex shaped room. In the center I have a hex shaped glass tube. In the center of the glass I want to put a crystal. Well when i build the glass everything is fine. I can see all the way thru it on both sides. Well when I do a rebuild everything appears normal until you move the view to inside the tube, then when your inside the tube the surfaces are very dark and you can't see thru to the outside. Even though when your outside you can see all the way thru to the opposite wall. since nobody will actually be inside the glass this wouldn't be a problem except when the crystal is placed inside the tube you can't see it from the outside (but you can see it inside). Does anybody understand what the hell I just said? BTW I tried making the glass tube semi-solid and that didn't seem to help.