GZDoom 3.5.0 Input Lag

Sat Aug 04, 2018 6:31 am

Since the new version of GZDoom is running in some sort of borderless windowed mode if I'm right, the mouse movement has input lag like if V-Sync would've been turned on.
This has bothered me so much to the point of switching back to 3.4.1.
Is there like a workaround or any chances of this being fixed in future releases?

Re: GZDoom 3.5.0 Input Lag

Sat Aug 04, 2018 7:13 am

If you mean GZDoom in fullscreen, then the behavior is exactly as it has always been: when a window in Windows covers the entire monitor the Desktop Window Manager (DWM) is disabled and there is no additional input lag.

If the window is not maximized, the DWM is active and there's approximately 1 frame of delay with occasional frame stuttering. This is a limitation of Microsoft's shitty DWM implementation - there's nothing we can do to fix that. Given that Microsoft now had 12 years to fix this, chances are they don't give a shit. :(

Re: GZDoom 3.5.0 Input Lag

Sat Aug 04, 2018 7:54 am

Ah I see, though it looks like DWM is active even on fullscreen since there is input lag, however it does not happen on 3.4.1.
Since I can't really get used to it, I will just stay on 3.4.1.
Also, thanks for the quick answer!

Edit: I just tried the Vintage version and it seems there's no input lag in this one, the mouse movement feels smooth and right.

Re: GZDoom 3.5.0 Input Lag

Sat Aug 04, 2018 8:21 am

Are you sure you are using identical ini files for both? I.e. if you forgot to disable vsync in the new one. There shouldn't be any difference with regard to input lag between 3.4.1 and 3.5

Re: GZDoom 3.5.0 Input Lag

Sat Aug 04, 2018 9:03 am

No, I never use V-Sync.

Re: GZDoom 3.5.0 Input Lag

Sun Aug 25, 2019 9:49 am

Sorry for this massive bump, but i was about to make a new thread.

I can confirm that in both the latest vintage build and GZDoom version 3.4.1 there is no input lag, while every version after it has.

This is very noticeable on 144hz+ refresh rates, and makes the mouse movement feel really sluggish.

To confirm that it wasn't just a placebo, i made some slow-motion recordings with my phone, there i could very clearly see the delayed mouse movement.

Re: GZDoom 3.5.0 Input Lag

Mon Aug 26, 2019 1:23 pm

Most likely new display code and not so great hardware, try LZDoom.

Re: GZDoom 3.5.0 Input Lag

Mon Aug 26, 2019 2:16 pm

It may also be the new timer code that got introduced around the same time. Hard to tell without system specs.

Re: GZDoom 3.5.0 Input Lag

Mon Aug 26, 2019 3:43 pm

LZDoom did not have any input lag whatsoever, my system specs are

I7-6700k 4Ghz, 32GB DDR4 RAM @ 3666 Mhz, Geforce GTX 1080 TI Stock

Operating System is Windows 10.

Re: GZDoom 3.5.0 Input Lag

Tue Aug 27, 2019 5:00 am

The new timer code predated GZDoom 3.3.2, it's in the legacy versions.

Re: GZDoom 3.5.0 Input Lag

Tue Aug 27, 2019 5:51 am

Ok. I wasn't sure about the exact date. Still, this is weird. On such modern hardware the 3.5 changes shouldn't have such an effect.

Re: GZDoom 3.5.0 Input Lag

Tue Aug 27, 2019 2:12 pm

I've been reading a bit, and it the reason why there's input lag is because windows 10 uses something called DWM, but it's disabled in fullscreen applications

Re: GZDoom 3.5.0 Input Lag

Sun Sep 08, 2019 4:43 pm

Ok, i've compared with older versions, and while there are indeed less input lag in previous versions, with nvidia's latest driver updates and the new "Ultra-Low Latency" feature, it's more subtle.

However, comparing with the Quake II sourceport "Yamagi Quake II", the difference is clear as night an day, which makes me think, maybe GZDoom/ZDoom needs a mouse input overhaul?

Re: GZDoom 3.5.0 Input Lag

Wed Oct 09, 2019 5:43 pm

I can confirm that it feels a bit weird compared to Zandronum.
I got used to it now, but Zandronum feels better.

Maybe it's the same problem idk.

It's also weird that it feels better with mouse at 1000hz polling rate.
In old versions it was the opposite - 125 hz polling rate felt the best and 1000hz felt weird.
Which is why I used 125 hz for gzdoom still.
But now 1000hz feels much better.

With 1000hz I can live with the input. But Zandronum still feels a little bit more smooth to me.

Re: GZDoom 3.5.0 Input Lag

Tue Mar 31, 2020 11:39 pm

As much as I hate to bump an old thread like happened already.. I feel it's better than making a new one.

I run GZDoom 4.3.3 on Windows 10 Home, specs as follows:
Dell Inspiron 7559
i7 6700HQ
16gb ram
GTX 960m driver version 445.75/Intel HD Graphics 530 (one of those annoying nvidia optimus designs..)

As stated before ever since the overhaul to the display system where manual resolution selections disappeared.. with it seemed exclusive full screen as well.

To the point: I cannot make the renderer tear. It doesn't matter if it's running at 200 fps on the 60hz panel, it doesn't tear, and the mouse feels horribly.. horribly delayed, as if vsync was turned on even though vid_vsync is set to false, changing it true only seems to cap the fps and not affect the perceived input lag.

Is the lag placebo? I don't think so. Every other game I've tried that supports exclusive full screen doesn't have this issue, and even GZDoom itself (Same version) running under Linux on the same laptop with the desktop compositor disabled feels responsive and very playable, it tears but I tolerate it for a responsive mouse.

As far as I know you cannot get Windows 10's desktop compositor to leave you alone without exclusive full screen. The referenced examples of design for this change in GZDoom (The "Where's my resolutions" thread that was made around the time this change came to be in drd builds) are all cursor driven games like Starcraft II and Diablo 3.. not twitchy first person shooters.

This hasn't ruined GZDoom for me, on my Windows 10 desktop with a 144hz gsync monitor the input lag is noticeable but negligible since its less than half the latency it would be on a 60hz panel.. but GZDoom on my laptop really sucks if I'm not living by the penguin.