This has happened many times before when hollowing out a polygon. Not always does this happen. But when it does It drives me insane!!

But why are you making a big hollow box with the skybox texture? Even for a 3D skybox you shouldn't ever have to do that.

After turning the exterior brush from a nodraw, it worked. Don't know why because i had a nodraw brush surrounding a skybox before and it worked just fine

FelixGriffin wrote:
The SKY shader is broken in Portal 2. You need to change them all to UnlitGeneric, then it'll work.

It depends what skybox you're using. I never had to change anything.

FelixGriffin wrote:
AFAIK all the default ones are UnlitGeneric?

Yup

.....We will blame it on witchcraft.

The box with the sky_camera is only needed for 3D skyboxes, where you want to create the impression that there are buildings and whatnot around the map.

Fracture wrote:
well i could just as easily put something in there.... maybe some metal beams

nope...

Let me explain:
A skybox is something that makes your level look bigger than it actually is.

A classic example of this is to have a shooter that plays inside, but with windows where you can see the outside (for example in a spaceship). The advantage is that you have an exterior that looks bigger than it is.

In games like counter strike and half-life skyboxes are used to create the sky. Instead of having a ceiling texture the whole map has a certain texture to the ceiling. This is cheap to render and it will look good.

Those are 2D- skyboxes, they are made easily in hammer by setting a (valid) skybox texture.

A 3D-skybox is a box with tools/skybox; far away from the actual map geometry, that has a sky_camera in it. Everything in this box is (by default) scaled down 1:16. so 16 units in the real map represent 1 in the actual skybox.

The advantage of this is that if you have a map like 4000x4000x4000 units and you want to make it look like it's 8000x8000x8000 you only need to make a skybox of 500x500x500 units and make sure the geometry in the skybox matches up your world geometry.

If you want to make an outside area, you can use a 2d-skybox. And unless you want to go all out on graphic design in a portal 2 map with loads of custom models and huge environments you shouldn't need 3d-skyboxes at all.

===
So putting in some random metal beams is a bad idea.
You need to:
1) keep in mind it's position compared to the world
2) keep in mind the lighting
3) keep in mind that the brush (and texture) is scaled up dramatically

I was just trying to take advantage of an easy fix to some strange glitch

@Fracture: if when you load the map the only thing you can see is the sky drowning everything, then do as GreyKarel said, delete the parameter *$ignorez 1* from ALL the six .vmt files of your skybox; that parameter is making the engine renders the skybox in a first plane, so the rest of stuff can't be seen correctly since it's "behind" the skybox, understand?

On the other hand, use the shader "UnlitGeneric" instead of "Sky" as Felix said (I mean into the .vmts again). For the sky textures to work fine, you only really need the following lines:

"UnlitGeneric"
{
    "$basetexture" "skybox/sky27bk"
    "$nofog" "1"
}

For that leak, if you already checked that the radius culling is not checked, there are only 2 possibilities:

• that box you made for the sky_camera is not made out of world brushes
• maybe the sky_camera center of origin is displaced. Go to Tools > Center Origins to see if that solves it.