DRD Team

Video should be mostly self-explanatory, but here's the gist: flatsprites are way too close to the ground, which causes z-fighting.
A temporary solution is to use A_Warp to move the actor above-ground, but I'd very much prefer not to do that in this case.

Perhaps some form of purely visual Z-offset feature is in order, akin to what is present in MODELDEF, but for the actors themselves?

Yes, I indeed forgot to add the handling for this.

I cannot help but wonder at this point if floor/ceiling decals for gzdoom are something to consider.

mostly fixed, but keep in mind that there are no means to combat z-fighting between overlapping flat and wall sprites. They have to write to the depth buffer and I can't increasingly offset their depth bias. This is an inherent and unfixable limitation of how this works.