Bug 231115 - Some Plasma desktop effects create flickering / garbled screen effects /black stripes on screen
Summary: Some Plasma desktop effects create flickering / garbled screen effects /black...
Status: REOPENED
Alias: None
Product: kwin
Classification: Plasma
Component: compositing (show other bugs)
Version: 5.93.0
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2010-03-17 16:26 UTC by crptdngl71
Modified: 2024-02-25 18:48 UTC (History)
7 users (show)

See Also:
Latest Commit:
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Sentry Crash Report:


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Description crptdngl71 2010-03-17 16:26:03 UTC
Version:           1.3 (using 4.3.4 (KDE 4.3.4), Debian packages)
Compiler:          cc
OS:                Linux (x86_64) release 2.6.33-1.slh.1-sidux-amd64

With some plasma desktop effects I get a flickering / garbled screen effect / black stripes when moving a window with the mouse.

Steps to reproduce:

1.) Open system settings window -> "Arbeitsflächen-Effekte" ("Desktop Effects") -> "Alle Effekte" ("All Effects")

2.) Select "Wabernde Fenster" ("Wobbly Windows") - this is one effect with which bug occurs, you may need to enable transparency as well -,

3.) Select "Anwenden" ("Accept").

Now move a window on the desktop and note the wobbly-effect, but also note a black flickering on the screen.

I have a sidux linux 64bit running with latest available standard kernel, NVIDIA binary driver (bug happens with beta driver and latest available driver for onboard graphics GeForce 6100).

The flickering area is special somehow as it only affects the right screen of my dualhead-setup. Left screen is an external flatscreen display 1680x1080 in size, right screen is internal notebook screen, 1280x800.

If you look closely then you will notice that the right screen (the one with the black stripes/garbled area) is redrawn very fast, whereas the left screen, which is not affected by the bug, is not.

xorg.conf: Twinview enabled, no xinerama enabled, so that windows can be dragged between both screens. On screen copies the area below the built-in notebook screen appears black, as it is the area missing to size-up the display to same size as external flatpanel screen.

I have noticed that once transparency option is enabled it cannot be turned off (i.e. even though it appears as disabled / switched off in the "all effects" window, windows keep their transparency option turned on).

The flickering/black stripes affects other effects as well, not only wobbly windows.
Comment 1 crptdngl71 2010-03-17 16:27:57 UTC
Maybe worth adding:
I have tried to create a screenshot video clip to capture the effect, but in the video the effect is gone and not recorded, and therefore it only appears on screen.
Comment 2 Thomas Lübking 2010-03-17 18:11:12 UTC
please turn off vsync in both, kwin and nvidia-settings, then restart kwin ("kwin --replace")
one can only sync to one screen - the other one will suffer
Comment 3 crptdngl71 2010-03-17 19:50:14 UTC
Did that - deactivated vsyncs in both NVIDIA settings and kwin, but this did not fix it. Checked frequencies of both screens as well, both are set correctly.
Comment 4 Wojciech Ryrych 2010-10-26 17:18:00 UTC
I can confirm that. Kubuntu 10.10, KDE 4.5.2 (4.5.1 was also affected) and get screen flickering with desktop effects enabled. It's worth noting that it wasn't the case in Kubuntu 10.4 with KDE 4.5.1.
Comment 5 Silner 2010-10-26 19:57:59 UTC
I can confirm this bug
Comment 6 Pablo 2010-11-08 23:39:19 UTC
Me too. I had it since 4.3 (when i moved from Gnome) but it wasn't too annoying. With 4.4.5 problems disappeared completely and then with 4.5.0 started again and worst, now i had to disable all desktop effects.

Archlinux
ATI Mobility Radeon X1400
KDE 4.5.3
xf86-video-ati 6.13.2
Linux 2.6.35-ARCH i686 Genuine Intel(R) CPU T2250 @ 1.73GHz GenuineIntel
Comment 7 Thomas Lübking 2010-11-08 23:50:37 UTC
this is unlikely the same issue.

for ati chips you likely either got a problem with the lanczos shader (affects eg. present windows but not desktop grid) or just for kms/dri - and of course disable blurring in doubt :-(

for the first one, check bug #243181, for the second one try to add "export LIBGL_ALWAYS_INDIRECT=1" to ~/.xprofile (interpreted by kdm - for eg. startx you'd have to add it to .xsession), then logout/login (just restarting kwin won't work, you'll have to pass it the env explicitly then)
Comment 8 Wojciech Ryrych 2010-11-09 13:12:29 UTC
Thanks! It seems my driver was also affected.

With:

[Blacklist][Blur]
DRI R300 Project=Mesa DRI R300 (RS400 5A61) 20090101 x86/MMX/SSE2 NO-TCL DRI2:-:1.5 Mesa 7.9-devel

[Blacklist][Lanczos]
DRI R300 Project=Mesa DRI R300 (RS400 5A61) 20090101 x86/MMX/SSE2 NO-TCL DRI2:-:1.5 Mesa 7.9-devel

Desktop Effects works to some extent (could be better - e.g no Wobbly Windows)
Comment 9 Pablo 2010-11-09 16:09:17 UTC
(In reply to comment #7)
> this is unlikely the same issue.
> 
> for ati chips you likely either got a problem with the lanczos shader (affects
> eg. present windows but not desktop grid) or just for kms/dri - and of course
> disable blurring in doubt :-(
> 
> for the first one, check bug #243181, for the second one try to add "export
> LIBGL_ALWAYS_INDIRECT=1" to ~/.xprofile (interpreted by kdm - for eg. startx
> you'd have to add it to .xsession), then logout/login (just restarting kwin
> won't work, you'll have to pass it the env explicitly then)

Well, every effect that involves moving a window (desktop grid, present windows, wobbly windows, minimize effect, etc) causes this flicker, better or worse depending on which one, but all of them are affected. Blurring just doesn't get enabled.

If it's not the same bug, should I report a new one? How? Because I don't see the difference with this one.

Is there a workaround to get the same performance as I had with 4.4.5?

Thanks for your time.
Comment 10 Thomas Lübking 2010-11-09 16:20:59 UTC
(In reply to comment #8)
> Desktop Effects works to some extent (could be better - e.g no Wobbly Windows)

sure that you didn't fall to the Xrender backend then?
Comment 11 Pablo 2010-11-09 16:34:56 UTC
(In reply to comment #10)
> (In reply to comment #8)
> > Desktop Effects works to some extent (could be better - e.g no Wobbly Windows)
> 
> sure that you didn't fall to the Xrender backend then?

Well, i have Effects -> Advanced -> Compositing type: OpenGL... not sure whether that's what you mean...
Comment 12 Pablo 2010-11-09 17:33:56 UTC
mmm... sorry, just realized that question wasn't for me...

Mental note: read before answer.
Comment 13 Thomas Lübking 2010-11-09 17:41:53 UTC
@pablo:

did you write comment #8? ;-P

your issue is (likely) different since the pitfalls of the nvidia and ati drivers are :-)
disabling direct rendering (LIBGL_ALWAYS_INDIRECT=1) will likely fix your issue (and recause the 4.4 state), while it's not the problem of the OP
Comment 14 Wojciech Ryrych 2010-11-09 18:05:36 UTC
Thomas, one more question. So there is nothing else to do than waiting for developers of open drivers to fix it?
Comment 15 Thomas Lübking 2010-11-10 19:20:05 UTC
deactivate possibly offending driver features, such as 
- KMS ("nomodeset", i wonder why distros don't offer a grub entry for this anyway)
- direct rendering ("LIBGL_ALWAYS_INDIRECT=1" - though working direct rendering would oc be preferable)

otherwise the bypassing of feature invocations (shaders) as by eg. the lanczos filter.

beyond this: "teach yourself to write GPU drivers" ;-P
Comment 16 Martin Flöser 2012-04-09 07:23:21 UTC
This bug report is for a quite old version and the complete stack (including the drivers) have improved.

Unfortunately this report is also mixing issues from different users who have the same result but not the same cause which makes it rather difficult to say whether the issue is resolved. Because of that I set to unmaintained. If the issue is still present please reopen and update the relevant information.
Comment 17 Luka Žaja 2013-09-02 17:26:37 UTC
I'm on Mint 15 KDE 32-bit and the same flicker occurs while moving windows around with the 'Wobbly Windows' effect enabled. KDE version is 4.10.5. Graphics are Intel integrated (Mesa DRI Intel Ironlake Mobile x86/MMX/SSE2), HD 3000 I believe. Also, I cannot capture this flicker with KSnapshot.
Comment 18 Thomas Lübking 2013-09-02 21:37:01 UTC
(In reply to comment #17)
> KDE version is 4.10.5. Graphics are Intel integrated (Mesa DRI Intel Ironlake Mobile x86/MMX/SSE2), HD 3000 I believe.

Please post the output of "qdbus org.kde.kwin /KWin supportInformation"

> Also, I cannot capture this flicker with KSnapshot.
Can you record a video with an external camera? (Ie. shooting the physical panel)
Comment 19 Luka Žaja 2013-09-09 15:59:31 UTC
(In reply to comment #18)
> (In reply to comment #17)
> > KDE version is 4.10.5. Graphics are Intel integrated (Mesa DRI Intel Ironlake Mobile x86/MMX/SSE2), HD 3000 I believe.
> 
> Please post the output of "qdbus org.kde.kwin /KWin supportInformation"
> 
> > Also, I cannot capture this flicker with KSnapshot.
> Can you record a video with an external camera? (Ie. shooting the physical
> panel)

Firstly, I would like to sincerely apologize for being so lazy and not replying a lot earlier.

Output of the command - http://paste.kde.org/pfbc2d7fc/

I've manage to record my desktop although I wasn't all that successful at configuring RecordMyDesktop (used similar software but on another platform) but the video clearly shows the flickering issue.
DL link - http://www.speedyshare.com/8kkxJ/flicker.ogv
 
On a side note, this happens in other distros as well, not only Mint 15. I've also tried to reproduce the issue in openSUSE, Mageia and Manjaro. The same thing happens.

Once again, I am really sorry for not posting this a bit sooner.
Comment 20 Thomas Lübking 2013-09-09 17:56:31 UTC
There's a mousepointer artefact after wobbling the last window, but i rather guess that's the (desktop, it's not a camshot) recording and the actual issue here is the texture clamping one (ie the black fragments between the window border and the actual window when wobbling)

Try either disabling the blur effect or setting the scale method to "Smooth"  - one by one and if neither does, both together (in "kcmshell4 kwincompositing", 2nd and 3rd tab) - then report the results.

No need to worry about being late or so - your problem, your pace ;-)
Comment 21 Luka Žaja 2013-09-10 16:47:12 UTC
(In reply to comment #20)
> There's a mousepointer artefact after wobbling the last window, but i rather
> guess that's the (desktop, it's not a camshot) recording and the actual
> issue here is the texture clamping one (ie the black fragments between the
> window border and the actual window when wobbling)
> 
> Try either disabling the blur effect or setting the scale method to "Smooth"
> - one by one and if neither does, both together (in "kcmshell4
> kwincompositing", 2nd and 3rd tab) - then report the results.
> 
> No need to worry about being late or so - your problem, your pace ;-)

Disabling "Blur" had no effect whatsoever but setting the scale method to "Crisp" ("Smooth" didn't help unfortunately) made the problem go away, for the most part. There are still a few pixels flickering here and there but nothing compared to what it was before.
What about changing the compositing device to XRender?
Comment 22 Thomas Lübking 2013-09-10 19:38:01 UTC
(In reply to comment #21)
> the most part. There are still a few pixels flickering here and there but
> nothing compared to what it was before.
Clamping errors are clamping errors, but apparently it depends on interpolation.

> What about changing the compositing device to XRender?
Doesn't support wobbling, but "OpenGL 1" would be interesting.
Comment 23 noodles.k 2016-08-25 07:58:19 UTC
Hello, I know this is is an old post but I had the exact same problem and found the solution ! (I've got a ATI HD5770)

In fact, this is a conflict between 2 effects : wobbly windows and maximize animation. I just deactivated the second one, and now the flickering/blinking "remain" on the other monitor has gone.
Works perfectly now !

ps. Also I'm almost sure this happens more with proprietary drivers than with free ones.