[SOLVED] Latte-Dock is causing screen tearing in KDE

Ridwan Rawriet · 2022-02-25 11:13:44

I'm using this video to check screen tearing. While using latte dock I see frequent tearing towards the bottom of the screen in full screen mode. Tearing goes away after quitting the dock. To check if it's because of some specific config I did, I deleted ~/.config/lette and ~/.config/lattedockrc. But no, the default config also causes screen tearing. It's less frequent and severe with the default config though.
Here are my config files though it seems like they aren't causing tearing.
~/.config/latte
~/.config/lattedockrc
Also, I've a nVidia card : (
How can I can fix this?

Last edited by Ridwan Rawriet (2022-02-27 08:25:38)

V1del · 2022-02-25 14:41:44

Does it help if you suspend the compositor on the fullscreen video or does that just lead to tearing in other parts? To test that press Alt+Shift+F12 before fullscreening. In general this can be "normal" due to multiple GL contexts overlaying each other. FWIW where do you see that? If with firefox can you test on a blink/chromium based browser? I definitely often have these issues with firefox and not with chromium.

Something more general you can try to set is enabling TripleBuffering on the nvidia driver with e.g. /etc/X11/xorg.conf.d/10-nvidia-tripleBuffer.conf

Section "OutputClass"
     Identifier "nvidia"
     MatchDriver "nvidia-drm"
     Driver "nvidia"
     Option "TripleBuffer" "on"
EndSection

and restarting xorg. A bit more out of the way but might be worth a shot with recent developments is to test behaviour on e.g. a Wayland session. I've been using that the past month or so and safe for some outliers it works quite well (though the system I've tested this on is intel, couldn't do a hands-on nvidia test yet, but a lot has happened here in the last few months with the current drivers)

Last edited by V1del (2022-02-25 16:51:56)

Ridwan Rawriet · 2022-02-25 16:43:52

Yes, suspending compositor eliminates all tearing. Actually that's how I've been watching videos in KDE nowadays. Either killing latte-dock or suspending the compositor eliminates tearing.

No, I just installed chromium and the same issue is there as well, exactly like firefox.

However then I thought of downloading the video and playing it with mpv, vlc and such. And I discovered something interesting!
With vlc and mplayer the result was same as firefox and chromium. But only with mpv, fullscreening the video was eliminating all tearing!! I played it like that in mpv about 4 times and there was no tearing at all. If I don't fullscreen it I do see tearing in mpv as well.

No, enabling triple buffer didn't solve the issue. After creating that file I rebooted but nothing changed.

As always, thanks for your answer, finding out that mpv in fullscreen can eliminate tearing, makes me feel a lot relieved!

V1del · 2022-02-25 16:50:55

Fullscreening in mpv will implicitly disable the compositor afaik. KDE has a config hint applications can use and I'm fairly certain mpv makes use of that to disable the compositor on fullscreen (though not on my system to effectively verify).

Last edited by V1del (2022-02-25 16:52:43)

Ridwan Rawriet · 2022-02-25 18:36:03

I see. So now I wish to set things in a way that when these specific applications (vlc, mplayer, firefox, chromium) go fullscreen composition will be blocked. I tried with settings>window management>window rules but there I cannot specify the rule for only when these applications go full screen. I see no option to specify that property, no in the window types.
Instead what, I've been able to achieve so far, suspends composition when ever those applications are run, even if they're not focused.

But I want composition to stop only when the applications are fullscreen and to start again after fullscreen mode is disabled. Any way to achieve that???

Last edited by Ridwan Rawriet (2022-02-25 18:43:55)

seth · 2022-02-25 21:24:27

You'll likely have to write a kwin script.
https://store.kde.org/p/1112546/ - I have no idea whether that still works and I haven't used KDE in years.
But you can maybe use it as a starting point.

Ridwan Rawriet · 2022-02-27 08:26:15

Thanks for providing a starting point.

Arch Linux

#1 2022-02-25 11:13:44

[SOLVED] Latte-Dock is causing screen tearing in KDE

#2 2022-02-25 14:41:44

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

#3 2022-02-25 16:43:52

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

#4 2022-02-25 16:50:55

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

#5 2022-02-25 18:36:03

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

#6 2022-02-25 21:24:27

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

#7 2022-02-27 08:26:15

Re: [SOLVED] Latte-Dock is causing screen tearing in KDE

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