Thok Barrier Problem

I am making a NIGHTS Beach Stage. I want to have water on the floor and ceiling, and have the Sky in the middle, like this:



However, I either get a Missing Texture Glitch like in the file, or I get checkers from Green Hill when it should be sky. There is also a colormap where it shouldn't be. See this picture:




This is where the error is located:



You can get the wad on my 4shared, as there are no attachments here for some reason.

http://www.4shared.com/file/-b2T5HoT/3D_NIGHT_BEACH.html

Posted in wrong fourm, sorry.

4shared requires people to make an account to download stuff. Upload it somewhere else, like Mediafire for instance.

Uploading took ages. Anyways here is Mediafire: http://www.mediafire.com/?pjsbjho4mtkefne

I can't look right now to know exactly what the problem is.

Still, one thing you could do is make the thok barrier have a floor/ceiling height matching the lowest point in the surrounding level (or lower), and make sure that F_SKY1 is the ceiling flat (ideally the floor texture, too, but IIRC this might introduce visual glitches - although I can't say as I understand why, when other Doom source ports can handle that scenario without any issues). The renderer deliberately renders the sky instead of a sidedef's upper-texture if the sector behind that sidedef has F_SKY1 as a ceiling flat... a feature id used heavily in outdoor segments (see the blue armor room in E1M1, for instance).

It kinda works for floors, too, but (going off of experience with PrBoom+, which may not be entirely accurate for our source port of Doom Legacy) if your viewpoint goes under the floor, it produces HOMs instead of the sky.

Great. My first idea goes wrong. I don't know if this helps, but there are going to be parts of the level where you can walk on ceilings. Wouldn't that show?

Wouldn't what show?

Well say you bring down the ceiling to the floor. Then wouldn't their be graphical glitches near the top of the ceiling? Last time, I tried to have a sky underwater, it stayed normal color, and not colormaped.

Well, yeah, you can't have the sky underwater for exactly that reason. I'm afraid you're just gonna have to design around that.

Maybe, for your thok barrier, put the ceiling low enough and the floor high enough to contain the water like a cup (or an upside-down cup, in the case of the ceiling), and put an invisible FOF in the resulting gap so that you can see the sky behind it?