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?
			
			
									
						
										
						Z-Fighting with Flatsprites
Moderator: Graf Zahl
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				Graf Zahl
														 - GZDoom Developer

 - Posts: 7148
 - Joined: Wed Jul 20, 2005 9:48
 - Location: Germany
 
Re: Z-Fighting with Flatsprites
Yes, I indeed forgot to add the handling for this.
			
			
									
						
										
						- 
				Major Cooke
 - Developer

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Re: Z-Fighting with Flatsprites
I cannot help but wonder at this point if floor/ceiling decals for gzdoom are something to consider.
			
			
									
						
										
						- 
				Graf Zahl
														 - GZDoom Developer

 - Posts: 7148
 - Joined: Wed Jul 20, 2005 9:48
 - Location: Germany
 
Re: Z-Fighting with Flatsprites
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.