Public bug reported:
I'm filing this bug against gtk+, but frankly I don't know exactly what
package is the culprit. It's occurring somewhere between the Gnome
"Appearance" preference panel and freetype, I suppose.
In summary, subpixel-antialiased font rendering to a Blue-Green-Red
(BGR) ordered display panel is broken in Maverick (10.10, Gnome). There
is NO DIFFERENCE between text rendered using the "RGB" setting and the
"BGR" setting. It is blurry and fringy on my BGR panel in both cases,
contrary to my experiences over the last few years with previous
releases, under which I always had sharp results.
I'm running Ubuntu 10.10, 64-bit, on a generic PC with an Nvidia 7900GS
card, using the latest proprietary Nvidia driver. The monitor is a Dell
1800FP, one of the few BGR panels out there, unfortunately, and it is
connected via DVI.
There is no change whatsoever when toggling between the two horizontal
subpixel options in the "Appearance" settings panel
(System->Preferences->Appearance->Fonts->Details). No matter how
closely I look, not a single pixel changes. I can see small changes (as
expected) when I go back and forth between "RGB" and "VRGB," for
example, but "RGB"<->"BGR" appears to do absolutely nothing.
I can verify that what I'm seeing (with either "RGB" or "BGR" selected)
is, in fact, RGB-ordered subpixel rendering. If I take a screenshot and
mirror it horizontally, which essentially turns RGB into BGR, what I see
is very nice, clear text on my screen. Unmirrored, it's ugly and
fringy.
I have tried various versions of the Nvidia driver, and it doesn't help.
Nor does using an unaccelerated driver. Nor does the status of compiz
desktop effects, on vs. off.
I have had excellent font rendering in the past, up through and
including Lucid (10.04).
In Firefox, for some reason, the systemwide RGB/BGR setting *does* work.
If I select "BGR" in the Gnome appearance preferences and refresh a web
page, it looks GREAT! Re-select "RGB," refresh, and it's ugly again.
All other text on the screen in Gnome/GTK applications remains
unchanged.
And Qt-based applications also work correctly, according to the settings
I have in ~/.fonts.conf. Those applications have great-looking text.
So there's something weird going on. This preference isn't being
respected by my desktop or the Gnome/GTK applications I use, and it has
worked perfectly in the past. My Google searches for others
experiencing this problem have come up empty.
In attempting to troubleshoot this problem, I tried numerous different
LiveCD images to see whether they worked. (I booted them in a kvm
virtual machine, and carefully inspected their on-screen output.)
Here's the summary:
Ubuntu 10.10: BROKEN - no BGR font rendering (both 32-bit and 64-bit
versions tested)
Xubuntu 10.10: BROKEN - no BGR font rendering
Ubuntu 11.04 alpha: BROKEN - no BGR font rendering
Ubuntu 10.04.1: WORKS FINE!
Kubuntu 10.10: WORKS FINE!
Obviously, in each case, I had to change the default rendering options
through settings.
So apparently BGR font rendering is OK in KDE/Qt, and broken in GTK-
based releases, both Gnome and XFCE. And the bug seems to be carrying
over into Natty, at least early in its cycle.
I look forward to seeing this regression corrected.
ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: libgtk2.0-0 2.22.0-0ubuntu1
ProcVersionSignature: Ubuntu 2.6.35-24.42-generic 2.6.35.8
Uname: Linux 2.6.35-24-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Fri Jan 14 22:14:58 2011
ProcEnviron:
LANG=en_US.UTF-8
SHELL=/bin/bash
SourcePackage: gtk+2.0
** Affects: gtk+2.0 (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug maverick
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https://bugs.launchpad.net/bugs/703191
Title:
BGR-ordered subpixel font rendering appears broken/nonfunctional in
Gnome/GTK+
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