Red Hat Bugzilla – Bug 490377
With VRGB font smoothing, qt4 displays garbage
Last modified: 2009-04-25 13:27:23 EDT
Created attachment 335275 [details] Qt4 application with RGB subpixel Description of problem: When VRGB is selected in subpixel font smoothing options in Gnome, Qt4 applications display garbage instead of text. Version-Release number of selected component (if applicable): qt-4.5.0-3.fc11.x86_64 How reproducible: Always. Steps to Reproduce: 1. Select VRGB. 2. Run psi or lmms. Actual results: Garbage fonts.
Created attachment 335276 [details] Qt4 application with VRGB subpixel
Just to ask the obvious: you do have freetype-freeworld or some other freetype build with subpixel antialiasing support, right?
What X video driver are you using?
I do not have freetype-freeworld, this is the default Fedora 11 freetype. It DOES appear to have subpixel rendering: I can see it with xmag. I am using xorg-x11-drv-ati (r300 radeon, not using KMS).
This is interesting, I just checked, subpixel antialiasing is disabled in F9, but got reenabled in F10 and devel.
Behdad said enabling subpixel antialiasing in the Fedora freetype was a mistake (because of patent issues), it's disabled again in current Rawhide and there's also a new F10 freetype build with it disabled (but I don't think it got pushed out). Still, Qt should not display garbage with it... This is also reproducible with Intel graphics according to: https://www.redhat.com/archives/fedora-list/2009-April/msg01110.html
I was using an r300 with KMS as it can be seen here: http://lists.fedoraproject.org/pipermail/fedora-kde/2009-February/001479.html The fix was to remove the hinting: http://lists.fedoraproject.org/pipermail/fedora-kde/2009-February/001624.html
Interesting, enabled full font hinting here in systemsettings, but I (still) can't reproduce.
nevermind, reading closer (sorry), missed the vrgb part. Confirmed universally broken here, regardless of hinting.
confirmed to that vgbr is broken likewise.
* Tue Apr 14 2009 Rex Dieter <rdieter@fedoraproject.org> - 4.5.0-14 - fix vrgb/vgbr corruption, disable QT_USE_FREETYPE_LCDFILTER (#490377)
kdeutils-4.2.2-2.fc10, kdetoys-4.2.2-2.fc10, kdesdk-4.2.2-2.fc10, kdeplasma-addons-4.2.2-2.fc10, kdeedu-4.2.2-1.fc10, kdebase-runtime-4.2.2-3.fc10, kdebase-4.2.2-2.fc10, kdeartwork-4.2.2-3.fc10, kdeadmin-4.2.2-2.fc10, kdeaccessibility-4.2.2-1.fc10, sigen-0.1.1-1.fc10, qgit-2.2-4.fc10.1, psi-0.12.1-2.fc10, kde-plasma-weather-1.0.0-3.fc10, arora-0.6-1.fc10, kde-l10n-4.2.2-1.fc10, kdegraphics-4.2.2-3.fc10, kde-i18n-3.5.10-4.fc10, kdepimlibs-4.2.2-3.fc10, oxygen-icon-theme-4.2.2-1.fc10, kdebindings-4.2.2-2.fc10, kdepim-4.2.2-3.fc10, konq-plugins-4.2.2-1.fc10, kdemultimedia-4.2.2-2.fc10, kdenetwork-4.2.2-1.fc10, kdegames-4.2.2-6.fc10, kdelibs-4.2.2-5.fc10, qjackctl-0.3.3-3.fc10, qsynth-0.3.3-4.fc10, kdebase-workspace-4.2.2-3.fc10, qt-4.5.0-14.fc10 has been pushed to the Fedora 10 testing repository. If problems still persist, please make note of it in this bug report. If you want to test the update, you can install it with su -c 'yum --enablerepo=updates-testing update kdeutils kdetoys kdesdk kdeplasma-addons kdeedu kdebase-runtime kdebase kdeartwork kdeadmin kdeaccessibility sigen qgit psi kde-plasma-weather arora kde-l10n kdegraphics kde-i18n kdepimlibs oxygen-icon-theme kdebindings kdepim konq-plugins kdemultimedia kdenetwork kdegames kdelibs qjackctl qsynth kdebase-workspace qt'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F10/FEDORA-2009-3389
kdeutils-4.2.2-2.fc10, kdetoys-4.2.2-2.fc10, kdesdk-4.2.2-2.fc10, kdeplasma-addons-4.2.2-2.fc10, kdeedu-4.2.2-1.fc10, kdebase-4.2.2-2.fc10, kdeartwork-4.2.2-3.fc10, kdeadmin-4.2.2-2.fc10, kdeaccessibility-4.2.2-1.fc10, sigen-0.1.1-1.fc10, qgit-2.2-4.fc10.1, psi-0.12.1-2.fc10, kde-plasma-weather-1.0.0-3.fc10, arora-0.6-1.fc10, kde-l10n-4.2.2-1.fc10, kdegraphics-4.2.2-3.fc10, kde-i18n-3.5.10-4.fc10, kdepimlibs-4.2.2-3.fc10, oxygen-icon-theme-4.2.2-1.fc10, kdebindings-4.2.2-2.fc10, kdepim-4.2.2-3.fc10, konq-plugins-4.2.2-1.fc10, kdemultimedia-4.2.2-2.fc10, kdenetwork-4.2.2-1.fc10, kdegames-4.2.2-6.fc10, kdelibs-4.2.2-5.fc10, qjackctl-0.3.3-3.fc10, qsynth-0.3.3-4.fc10, kdebase-workspace-4.2.2-3.fc10, qt-4.5.0-14.fc10, kdebase-runtime-4.2.2-4.fc10 has been pushed to the Fedora 10 testing repository. If problems still persist, please make note of it in this bug report. If you want to test the update, you can install it with su -c 'yum --enablerepo=updates-testing update kdeutils kdetoys kdesdk kdeplasma-addons kdeedu kdebase kdeartwork kdeadmin kdeaccessibility sigen qgit psi kde-plasma-weather arora kde-l10n kdegraphics kde-i18n kdepimlibs oxygen-icon-theme kdebindings kdepim konq-plugins kdemultimedia kdenetwork kdegames kdelibs qjackctl qsynth kdebase-workspace qt kdebase-runtime'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F10/FEDORA-2009-3389
kdeutils-4.2.2-2.fc10, kdetoys-4.2.2-2.fc10, kdesdk-4.2.2-2.fc10, kdeplasma-addons-4.2.2-2.fc10, kdeedu-4.2.2-1.fc10, kdebase-4.2.2-2.fc10, kdeartwork-4.2.2-3.fc10, kdeadmin-4.2.2-2.fc10, kdeaccessibility-4.2.2-1.fc10, sigen-0.1.1-1.fc10, qgit-2.2-4.fc10.1, psi-0.12.1-2.fc10, kde-plasma-weather-1.0.0-3.fc10, arora-0.6-1.fc10, kde-l10n-4.2.2-1.fc10, kdegraphics-4.2.2-3.fc10, kde-i18n-3.5.10-4.fc10, kdepimlibs-4.2.2-3.fc10, oxygen-icon-theme-4.2.2-1.fc10, kdebindings-4.2.2-2.fc10, kdepim-4.2.2-3.fc10, konq-plugins-4.2.2-1.fc10, kdemultimedia-4.2.2-2.fc10, kdenetwork-4.2.2-1.fc10, kdegames-4.2.2-6.fc10, kdebase-workspace-4.2.2-3.fc10, qt-4.5.0-14.fc10, kdebase-runtime-4.2.2-4.fc10, qjackctl-0.3.4-1.fc10, qsynth-0.3.3-6.fc10, kdelibs-4.2.2-7.fc10 has been pushed to the Fedora 10 stable repository. If problems still persist, please make note of it in this bug report.
fyi, freetype lcd_filter for vrgb/vgbr is fixed in qt-4.5.1.