ZDoom

Akin to how one can force XY billboarding on an actor, would it be possible to make it so an actor's sprites don't get pushed up/down by the GL renderer sprite clipping option?

I think this feature is due for some serious rethinking anyway. There's already the SPROFS lump where you can override offsets for the hardware renderer, but with the current implementation it is still subjected to sprite clipping considerations.

For the time being I won't add any other means to mess around with this because ultimately they'll just complicate matters.

This. I have some fire actors that look like total ass with the sprite clipping options on.

What really complicates matters is that I just accidentally made an actor which has some rotations (notably 1, 2 and 8) "moved out of the floor", while rotations 3-7 stay as defined in the image offsets, and all that only happens if the actor is +ISMONSTER (but not +NOGRAVITY). So making a flag that unconditionally disables all the magic threshold should actually make things simplier

https://imgur.com/a/teDiMUr
Top to bottom: rotation 1, rotation rotation 2, rotation 3

The only way to fix this right now, is making a duplicate attached actor that does all the drawing (but doesn't have ISMONSTER flag), while my main actor will still have ISMONSTER for being counted and blocked by lines...