Qt 5 uses grayscale instead of subpixel font antialiasing

[Brian Marshall]

Qt 5 applications like Qt Creator or the Ubuntu web browser (webbrowser-app) use grayscale font antialiasing. GTK 3, GTK 2, and Qt 4 use subpixel antialiasing as expected, so fonts in Qt 5 look weird. Attached screenshot shows an example of the problem.

This upstream bug report might be related: https://bugreports.qt.io/browse/QTBUG-36445

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: libqt5gui5 5.2.1+dfsg-1ubuntu14.2
ProcVersionSignature: Ubuntu 3.13.0-44.73-generic 3.13.11-ckt12
Uname: Linux 3.13.0-44-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Feb 2 19:35:10 2015
InstallationDate: Installed on 2014-08-30 (156 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: qtbase-opensource-src
UpgradeStatus: No upgrade log present (probably fresh install)

[Brian Marshall (bmars)]

This might be related also: <https://bugreports.qt.io/browse/QTBUG-27106>. That bug talks about disabling antialiasing, but the patch for it makes Qt read subpixel and antialiasing settings from Xft, instead of just hint style: <https://qt.gitorious.org/qt/qtbase/commit/6efa8cd70aedf13edef9143eb57b52bd175fb748>. I haven't tried Qt 5.4 to see if it helps, though.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Alex (eneeen)]

Here is enlargement of screenshot from Ubuntu-Budgie and Krita. This issue seems still unresolved.

[Simon Quigley (tsimonq2)]

@Alex what release of Ubuntu Budgie are you running?