I’m having a continual problem with being able to see through walls. While that may seems like a genius idea, it’s getting rather annoying.
http://i182.photobucket.com/albums/x305/Entoros/th_clipping.png
Basically, my skybox shows right through into the other areas, rather than the walls. How can I fix this (or do I just have to put the skybox around my entire map)?
Put a skybox around the entire map or move the brushes. As for the invisible walls, playerclip/nodraw both work fine.
Problem: You aren’t compile with VVIS on normal and hence, the map is drawn when you shouldn’t be able to see it.
Solution: Compile with VVIS on normal
It doesn’t seems like a genius idea, at all.
If I remember right, this is happening because you’re standing in a visleaf that can see into the visleaf in that dark grey room. Because there’s a skybox in the way, you can see into the second room- otherwise, it’d still be getting rendered, you just wouldn’t be able to tell.
I don’t remember exactly how you fix it, but it involves either using some kind of optimization technique (hint brushes, occluders, areaportals) to separate the two areas, or redoing your layout in a way that makes more sense. 
If you’re trying to make a realistic map, just make the room into an outdoor building, or something.
Don’t draw a big skybox around your map; it’s a terrible idea for a variety of reasons. What exactly are you trying to accomplish with this map? That has some bearing on how you go about fixing it.
God, no. Stop giving mapping advice.
If you want an invisible wall, use playerclip or clip brushes. Nodraw brushes are still world brushes and will carve up visportals and turn them into fail.
I have been doing so. Still got the problem.
It’s a joke.
So if I place a playerclip brush over the dysfunctional walls, they should show up?
Playerclip and clip are to block players and objects as if a wall were present, but not rendered, they don’t do anything else.
You don’t have “dysfunctional” walls, your map is poorly built. Likely, you have a leak somewhere in the map that’s preventing VIS from running properly, or you aren’t running VVIS at all which explains why you can see the entire map from anywhere in the level.
I’m sure there’s not a leak, since I’ve checked the compile logs and my water shows up. I’m also running everything as normal (including VVIS), so I don’t think that’s a problem.
Would anything else cause it?
I had this problem once before when having a corner in the map, and the corner was covered in the skybox texture. I just blocked off the area since it was just a quick map.
Happened to me too sometimes. I think you need to have 2 skybox textures. Like. If you have a big block seperating 2 parts of the map that are next to eachother, you’ll need to cut the skybox block in half.
Worked for me, probably isn’t a very good solution.
Might not even be what you’re asking for.
This requires a basic understanding of the engine to get the point across, but basically anything that the engine has to render brush wise it will render infront of the skybox. Any face touching the void is automatically nodrawn and thus becomes see through, so basically the room which is behind the skybox textured brush is being rendered infront of the skybox and you can see inside because the outside faces have been nodrawn. 2 possible solutions, firstly, create a door and areaportal combo in that hallway leading to the hidden room, or secondly put something infront of that room to obstruct the players view.
