I'm trying to import the extended sky textures from skulltag to remove the sky stretching just because that bothers me a lot. But I would really rather keep freelook, so I thought I could use the extended skies to make the experience a bit more tolerable. Unfortunately, for some reason, when I import the skies, it refuses to account for the extended height, and as a result it takes the upper half of a sky texture and tiles that.
What I find strange and what's really confused me is when I, say, import Doom 2's sky 1 into Ultimate Doom, and then call it sky 5. If I use a non-typical map to call on this (like E4M10 or whatever), it works properly. If I call on it from a standard map, whether I change its filename or not, it results in the tearing. But also if I use a non-typical map to call on the replaced sky (sky4) it ALSO results in the tiling.
I'm completely stumped. I have no idea what's causing this. It makes no sense to me. I'm usually pretty good at figuring this stuff out on my own, but in this case... I can't find any difference between when it works and when it doesn't. I've torn open unrelated WADs that use their own extended skies and I can't understand why it works for those wads but not mine.
What am I doing wrong?
UPDATE
I've since discovered that converting the images' palettes into Doom Gfx partially fixes the issue (as long as I still call on it with a nonstandard name). However, it's now created a new problem.
Allow me to demonstrate:
Spoiler:Somehow, the "horizon" has been lifted a few pixels. It's enough to be visible with standard play, even without jumping. (KDitD has it really bad.)
For comparison, this is where the horizon line should relatively be located:
Spoiler:The wiki has not been particularly helpful. Its article on skies is incredibly short and doesn't really address any of these issues. The only thing of note I found is how textures of 200 pixels in height (which these are, exactly), it says "Unstretched, baseline is on horizon, and top is at the top of the screen when looking fully up."
Except if that's the case, why does this happen with the exact same textures used elsewhere (using D2 Dark World as the example, but plenty of other mods have this same effect):
Spoiler:And while it's true this isn't the super cleanest result, it is far preferable to what is presently occurring. You spend more time looking at the horizon in Doom than you do looking as far up as you can, freelook or otherwise (especially in software mode).
I just don't understand. I know it can work, clearly; I've seen it many times. And yet, I've tried reverse-engineering every PWAD I can think of that uses non-stretched skies, and can't find a difference between theirs and mine. It's not in MAPINFO, it's not the images themselves (unless there's some additional property I'm not aware of), it's not markers...
I ask again. What am I doing wrong, here?