How do I stop this from happening? That's the wood-framed glass ceiling of my central area that you can see bits of. I've got the backsides of the glass and the wooden beams nodraw'd and then covered by a layer of 2d skybox which also has the backs nodrawed. Even when the backs were not nodrawed, I could still see the glass ceiling from the pond area. This same issue comes up when you grapple onto the glass ceiling or stand on the bottom wood frame (it acts like a ledge, for snipers). You can see clear into the spawn rooms and hallways. How do I prevent this see-through-ness? It's been a long time since I've done any mapping so I can't remember how I resolved this issue a few years back when I encountered it.