KWin-LowLatency: An Effort To Yield Less Stutter & Lower Latency With The KDE Desktop

[aufkrawall]

oiaohm I just fired up AC: Unity on both Windows and Linux to check for a shadow rendering bug, and it both equally tears like hell in fullscreen without vsync.

[oiaohm]

oiaohm I just fired up AC: Unity on both Windows and Linux to check for a shadow rendering bug, and it both equally tears like hell in fullscreen without vsync.

That test shows issues just with userspace disable of vsync in form. Run X11 without a compositor with vsync off in the x11 server you will see a change for the worse. You cannot even drag basic windows around the X11 screen without them tearing in that setup let alone more fancy test. Of course that does not help the Unity test..

[oiaohm]

I see only tearing when moving windows fast around the Xfce desktop. Applications work fine without compositing and scrolling in the web browser does not cause tearing. So I do not use the compositor or anything that slows down system performance.

X11 server will in fact tear with vsync on with compositor off if you drag windows fast enough because the X11 server vsync implementation is nice and buggy.. Lets just say tearing gets worse when you turn X11 vsync off as well.

Vsync total off scrolling the web browser it will from time to time tear there as well on x11 server. The fact you said it was not tearing you have left the servers vsync on..

[aufkrawall]

Without compositor or TearFree, Xorg can only be free of tearing for fullscreen windows (because they trigger page flipping). Drag a video player window playing a juddertest video to the very top or bottom of the screen to spot the tearing in windowed mode. That has nothing to do with the chosen DE, believing otherwise is just a proof of incompetence.

That being said, I don't know why anyone should care about the tearing without compositor or TearFree. These features are there for a purpose and should function without issues (otherwise fill a bug report)...

[oiaohm]

In gnome3, kde and some others you have tearing, but not with the Xfce desktop. The Xfce desktop is light and fast without compositing and any vsync on.

Note that when Tearfree is auto, it is off normally. See man amdgpu.

Really debianxfce you cannot read and understand.

If this option isn't set, the default value of the property is auto, which means that TearFree is on for rotated outputs, outputs with RandR transforms applied and for RandR 1.4 slave outputs, otherwise off.

Tearfree auto is half on. Heres the fun fact with xfce when screen it not rotated it sets RandR rotation of 0 what effectively means you have turns on TearFree to on because to the system the screen is rotated. Welcome to X11 stupidity.

XFCE TearFree is on unless you particularly set it off.

[retardxfce]

You invent your own theories., an example:



A property that has values auto, on and off can not be half on. Tearfree is a digital value, not analog. Wayland is garbage and will never replace X, see:
https://gitlab.freedesktop.org/wayland/wayland/issues

http://lmgtfy.com/?q=xfce+how+to+fix+screen+tearing

[xfcedebian]

http://www.oc-burner.de/ftp/Videos/juddertest/old_1080p_files/juddertest_120.mp4

When running above I have a couple of centiliters tearing at the bottom of the bar. I can not see such a thing when watching TV with VLC. The Xfce desktop is light and fast, try it yourself.

Well said. I have absolutely no clue what this user is doing not using Xfce. Probably an IBM drone. I don't experience any tearing on my Xfce desktop either as long as I've had a few shots of vodka before hand. It's like the users here don't even know how to use good software.

[skeevy420]

Damn, I think we've driven him into a schizophrenic psychosis.

[oiaohm]

A property that has values auto, on and off can not be half on. Tearfree is a digital value, not analog.

Half on is possible even with Tearfree. Because compositor can say Tearfree on and from mesa application can say Tearfree off. This means the buffer merges inside the application are done without consideration to tearing but the output tearing is considered. This is the half on state. Part of the stack has it on part of the stack has it off.

Wayland is garbage and will never replace X, see:
https://gitlab.freedesktop.org/wayland/wayland/issues

That not many issues.

https://gitlab.freedesktop.org/groups/xorg/-/issues?state=opened

Really Wayland does not have that many bugs.

[retardxfce]

https://www.phoronix.com/forums/forum/phoronix/general-discussion/1095519-am-i-the-only-one-that-thinks-policykit-is-retarded

Screen tearing is a feature not a bug. My XFCE desktop is so fast that it causes a rift in the space-time continuum which results in screen tearing. Plus, no IBM desktop has screen tearing, this makes my XFCE desktop very unique and super cool.