Bug 173089

Summary:	Subpixel font rendering causes problems in effects
Product:	[Plasma] kwin	Reporter:	Cyrill Helg <phlogi1>
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	gio.grifis
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	unspecified
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Shows the font

Description Cyrill Helg 2008-10-18 13:11:28 UTC

Version:           svn trunk (using 4.1.70 (KDE 4.1.70 (KDE 4.2 >= 20081016)), compiled sources)
Compiler:          gcc
OS:                Linux (i686) release 2.6.27-zen1

I can't understand why the font looks like that. Maybe it should pickup settings from plasma theme or it should be configurable in the plugin itself.

The look of the font right now is just ugly in my opinion.

See the screenshot.

Comment 1 Cyrill Helg 2008-10-18 13:11:53 UTC

Created attachment 27993 [details]
Shows the font

Comment 2 lucas 2008-11-20 15:16:14 UTC

Which graphics driver are you using? Have you seen this happen to any other, non-KWin fonts?

Comment 3 Cyrill Helg 2008-11-20 15:46:55 UTC

Its happening on fglrx and nvidia, I have never seen this font in any other application I think.

Comment 4 lucas 2008-11-20 15:56:08 UTC

Go into system settings -> appearance -> fonts. What is your "general" font set to? Are you using anti-aliasing or a different DPI settings? Does the glitching still occur when set to something else (Try a few)?

Comment 5 Cyrill Helg 2008-11-20 16:05:29 UTC

General is: Bitstream Vera Sans Regular 8. I'm using a dpi of 90. Is this feature using the general font? I don't think so, because the font looks much bigger. However when I change the size it changes as well, but still looks ugly.

I'm still investigating.

Comment 6 Cyrill Helg 2008-11-23 13:07:33 UTC

I just remembered that I'm using patched font system:
http://forums.gentoo.org/viewtopic-t-511382-postdays-0-postorder-asc-start-0.html

But as far as I know these patches are in kubuntu as well, so....

Whats different for this font in kwin than all others? Becaus I have this ugly font there only...

Comment 7 lucas 2008-11-23 14:27:40 UTC

Can you confirm that removing the patch fixes the problem?

Comment 8 Cyrill Helg 2008-11-24 23:05:57 UTC

I have disabled the patches, recompiled the affected patches, restarted kde but I'm still having the ugly font.

Comment 9 Giovanni Masucci 2008-11-25 03:41:04 UTC

I have this problem to on my intel card, since kde 4.0.
I have it in kde from kubuntu, opensuse and from a self-compiled kde 4.7.73...
it's connected with sub pixel hinting: disabling it from system settings makes the fonts look ok.

Comment 10 lucas 2008-11-25 03:46:20 UTC

I can now reproduce.

Comment 11 lucas 2008-11-25 16:15:28 UTC

SVN commit 888946 by lmurray:

Paint effect text onto a QImage instead of a QPixmap. Makes OpenGL mode
faster, XRender slower and works around a subpixel font rendering problem.
BUG: 173089

 M  +7 -7      kwineffects.cpp  


WebSVN link: http://websvn.kde.org/?view=rev&revision=888946