if game started with -fitz commandline parameter, you can see some flickering shadows. for examle in e1m1 on the secret elevator that leads to quad.
P.S. what actually -fitz does? apart from playing demos at startup
Yeah, the z-fighting is annoying and a well known problem. It affects pretty much all glquake engines, but not the original software renderer.
-fitz does the following:
-plays demos at startup
-shows clock in the statusbar (when you press tab)
-prompt before quitting
-prevents loading quakespasm.pak. This contains a replacement default config (WASD keybindings, mouselook enabled, autoaim disabled), as well as patched for some of the original maps to fix z-fighting
So the last point is why you get the z-fighting with -fitz, because it disables loading the patched maps.
There's an alternative fix which is enabling "gl_zfix 1" in the console, but this is disabled by default because while it fixes the flickering, it creates cracks that can also reveal secrets (even in maps that are properly constructed without z-fighting).
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Yeah, the z-fighting is annoying and a well known problem. It affects pretty much all glquake engines, but not the original software renderer.
-fitz does the following:
-plays demos at startup
-shows clock in the statusbar (when you press tab)
-prompt before quitting
-prevents loading quakespasm.pak. This contains a replacement default config (WASD keybindings, mouselook enabled, autoaim disabled), as well as patched for some of the original maps to fix z-fighting
So the last point is why you get the z-fighting with -fitz, because it disables loading the patched maps.
There's an alternative fix which is enabling "gl_zfix 1" in the console, but this is disabled by default because while it fixes the flickering, it creates cracks that can also reveal secrets (even in maps that are properly constructed without z-fighting).