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Sorry if this is the wrong place. I couldn't figure out which is the most appropriate forum.

Anyway, I'm trying to figure out a way to vertically scroll a sky texture. Mapinfo only allows for horizontal scrolling. I see that you can define a vertical scrolling effect in the SKYDEFS lump in ID24, and that Zdoom has implemented some ID24 features but I'm having a hard time finding out if that specific feature has been implemented. Is it, and if not, is there another way to do it without setting up some kind of elaborate skybox?

You can´t scroll sky texture verticaly but you can do it in a wall texture (linedef action 103) and with that in mind you can create a sector with the desired visuals for your skybox and use the Skybox Viewpoint actor on it.
Here you have an example of mine (it doesnt have vertical scrolling but ilustates how you can do a custom skybox whit this method):
https://bsky.app/profile/jovenoculto.bs ... 4ntro23k2m