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GZDoom FPS limit?

Posted: Fri Sep 29, 2006 7:24
by Nash
Is it just me or does GZDoom limit the FPS to 60? I'm getting over 100 FPS in ZDoom, but in GZDoom, the highest value it'll go to is 60.

Posted: Fri Sep 29, 2006 7:52
by Alter
Yeah it's stupid that there's no max_fps cvar!

Posted: Fri Sep 29, 2006 8:12
by wildweasel
I believe that's to do with the VSync setting (which I assume GZDoom has set to on by default).

Posted: Fri Sep 29, 2006 8:33
by Nash
Thanks wildweasel. That was it. Turning off vsync removed the 60 FPS cap, but the screen does seem to tear a bit as I turn around sometimes. Oh well, not really a big issue.

Posted: Fri Sep 29, 2006 8:49
by Graf Zahl
You are cheating yourself with these 'higher' frame rates. You don't gain anything from them because the monitor still doesn't work faster than 60 fps. All you get is the tearing effect. I only play with vsync on. It has 3 advantages:

1. It doesn't tear
2. It evens out the frame rate. The game can become really jerky if it alternates between 150 fps and 300 fps depending on what you are looking at. But with the constant 85 fps I am getting from my monitor this is only an issue with maps that actually drop below that.
3. Since the GPU has less to do it doesn't get as hot. With vsync off my fan starts to get really loud quite quickly. With vsync on it takes much longer to reach that point.

Posted: Fri Sep 29, 2006 10:35
by Cutmanmike
Does "Tear" mean the skewing of walls when you turn and run around corners etc? I wondered why the hell that was happening.

Posted: Fri Sep 29, 2006 13:17
by Nash
Noted, Graf. *turns vsync back on*

Cutty - with vsync off, you'll see tearing if you just stand still and mouselook around. It just looks like a certain section of the screen doesn't update as fast enough as others, so the picture appears to be cut into several pieces. That's tearing.

Try it for yourself to understand how it looks like.

EDIT: The easiest place to see tearing is in daedalus.wad. Step into the teleporters and watch the effect with and without vsync. You'll clearly see the difference.

Posted: Fri Sep 29, 2006 16:29
by SlayeR
I never use vsync, couldn't care less about tearing :P It always seems to screw with mouse movement.

Posted: Fri Sep 29, 2006 16:43
by wildweasel
The only reason I use vsync is because I can see the tearing more easily on my LCD screen. It's barely noticeable on CRT monitors, from my experience.

Posted: Fri Sep 29, 2006 17:40
by Graf Zahl
I notice it all the time. It's as visible there as on LCDs.

Posted: Sat Sep 30, 2006 3:44
by SlayeR
I find it much less visible on this LCD than on my old CRT.

Posted: Tue Jan 02, 2007 12:18
by Softie
When I start GZDoom the vid_vsync variable is set to false, even so it really is on. If I just reset it to false then that takes effect. Is this a bug?

Posted: Tue Jan 02, 2007 13:42
by Graf Zahl
Most likely it is. The handling for this variable has changed for the most recent version.