Bug 289849

Summary:	window decorations drawn slow
Product:	[Plasma] kwin	Reporter:	Silver Salonen <silver.salonen>
Component:	kdecorations	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED DUPLICATE
Severity:	normal
Priority:	NOR
Version:	4.9.98 (RC3)
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Screencast

Description Silver Salonen 2011-12-26 12:29:20 UTC

Version:           unspecified (using Devel) 
OS:                Linux

After upgrading to 4.8 beta (currently using RC1) window decoration started being drawn quite slowly (about 1 second). I don't use desktop effects, because I have rather old graphics card: NVidia 7300.

Reproducible: Always

Steps to Reproduce:
Open 2 windows and switch between them

Actual Results:  
Window decorations (read: title bar) are drawn (read: color being changed) very slow.

Expected Results:  
Change should be very quick.

I tried it also under a new user and the switch was quick with desktop effects enabled, but in that case the title bars were somewhat broken - shifted to right a bit (so much that I couldn't see any buttons in the right corner).

Comment 1 Silver Salonen 2011-12-26 13:09:10 UTC

Created attachment 67125 [details]
Screencast

This is how switching windows looks like

Comment 2 Martin Flöser 2011-12-26 13:23:37 UTC

which Qt graphicssystem are you using?

Comment 3 Silver Salonen 2011-12-26 13:33:02 UTC

What do you mean? Currently I have Qt 4.8.0 installed.

Comment 4 Martin Flöser 2011-12-26 13:35:46 UTC

>  What do you mean? Currently I have Qt 4.8.0 installed.
so most likely you use graphicssystem raster. Try with native:

kwin --replace --graphicssystem=native &

Comment 5 Silver Salonen 2011-12-26 13:49:24 UTC

Ah, I see. Any way to disable raster graphicssystem without scripting?

*** This bug has been marked as a duplicate of bug 284291 ***

Comment 6 Thomas Lübking 2011-12-26 20:30:32 UTC

https://git.reviewboard.kde.org/r/103430/
https://git.reviewboard.kde.org/r/103431/

I doubt the GUI part will make it for 4.8 (?!) but maybe we can still add the cofig item before 4.9 - no idea

@Me
alter the patch to preselect native w/o compositing enabled at startup

Comment 7 Silver Salonen 2011-12-26 21:16:50 UTC

Actually, when I had desktop effects enabled, title bar was broken, but when I replaced kwin with native, title bars were OK. Does it make sense?

Comment 8 Thomas Lübking 2011-12-26 22:53:04 UTC

yes, known issue - your GPU presumingly doesn't support NPOT?!
(do "glxinfo | grep GL_ARB_texture_non_power_of_two" - there's probably no output)

Comment 9 Silver Salonen 2013-01-23 09:08:09 UTC

I have now upgraded to 4.10 RC3 and window decorations are drawn slowly again. It happens with desktop effects enabled and without, and also with "graphicssystem=native".

Actually I do get an output for that:
$ glxinfo | grep GL_ARB_texture_non_power_of_two
    GL_ARB_texture_mirrored_repeat, GL_ARB_texture_non_power_of_two,

Comment 10 Thomas Lübking 2013-01-23 09:17:37 UTC

[ ] You were using Plastik?
[ ] You are now using QML based Plastik?
[ ] The "Laptop" deco is still fast?

-> QML hates the native graphicssystem, bug #313016

Please re-close this and hook there, but it's basically a won't fix (on the technical layer, qml likely won't ever be fast on the native system)

Comment 11 Silver Salonen 2013-01-23 09:23:04 UTC

It was all Plastik indeed - if I set decorations to Oxygen it's OK.

*** This bug has been marked as a duplicate of bug 284291 ***