Bug 344901

Summary:	Complete Repaint on Preview(?)
Product:	[Plasma] kwin	Reporter:	Georg Grabler <ggrabler>
Component:	scene-opengl	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	normal	CC:	justin.zobel
Priority:	NOR
Version First Reported In:	5.2.1
Target Milestone:	---
Platform:	Kubuntu
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Georg Grabler 2015-03-06 13:42:24 UTC

Hello,

We do have window preview functions in Plasma5/KWin. I see this especially when OpenGL apps are open (you can see it best on OpenGL apps), but it happens in normal circumstances as well.

It seems as if a complete screen repaint is triggered (can be seen because windows turn black and get re-painted) when you go over a task in the taskbar, wait for the preview to appear, and switch to a 2nd task in the taskbar (just hovering it, not actually switching to the other application). At the switch, it seems as if the complete screen is repainted - decorations and elements in the windows.

I tested it on NVidia and Intel HD3000 in KUbuntu 15.04 beta1, but had the same experience on Archlinux with Arch packages.

Reproducible: Always

Steps to Reproduce:
1. Open an app (best seen with a OpenGL app), maximize it
2. Open a 2nd app, and switch back to the OpenGL app
3. Hover the OpenGL app in the taskbar until preview appears
4. Move the mouse to the 2nd task bar entry.

Actual Results:  
When the preview of the 2nd window is shown, it seems to trigger a complete screen repaint.

Expected Results:  
Not a complete screen repaint?

Actually it's more an enquiery if this is really necessary, it's annoying if a whole window turns black for like a few hundred ms (enough to see it properly) until the content is displayed again. It's "not sexy" ;-).
Currently (I think!) there is no workaround, since I couldn't find the option to turn off the preview function :D.

Comment 1 Thomas Lübking 2015-03-06 14:15:36 UTC

You should not see a screen repaint and that should esp. not turn anything black.

Is the taskbar, preview or titlebar still visible or does the entire screen turn black?
Is the pointer still visible?

Please attach the output of
   qdbus org.kde.KWin /KWin supportInformation

Comment 2 Justin Zobel 2020-11-12 00:15:21 UTC

Georg I'm unable to reproduce this issue on the latest Plasma from git master.

Can you please test and confirm if this issue is still occurring or if this bug report can be marked as resolved. I'm setting status to "needsinfo" pending your response, please change back to "reported" or "resolved" when you respond, thanks.

If the issue does persist please provide the info requested in Comment 1.

Comment 3 Bug Janitor Service 2020-11-27 04:33:51 UTC

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!

Comment 4 Bug Janitor Service 2020-12-12 04:34:03 UTC

This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!