Hi,
Marmuta wrote a patch for this issue, that I applied to the gtk+3.0 package shipping currently in the development version of Ubuntu zesty. You will find the corresponding debdiff attached to this bug thread.
Marmuta performed tests with org.gnome.desktop.interface scaling-factor = 2 , where few issues are left for Onboard on hidpi screens, that are not related to gtk, but rather to unity-greeter or gnome-screensaver. He did not notice any issue with scaling-factor = 1.
Can a sponsor please review the debdiff?
Thanks in advance.
Francesco
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Original description:
See attached screen shot. Blue is a GtkPlug, black is a GtkSocket. Source code below.
What I expect to happen is that the GtkPlug has the same size as the GtkSocket.
What actually happens is that GtkPlug only covers a quarter of the area of the GtkSocket.
Impact: Onboard on HiDPI displays is near unusable at login and lock screen, aka unity-greeter and gnome-screensaver. Original bug report here: https://bugs.launchpad.net/bugs/1562734.
Steps to reproduce:
- build plug and socket samples from below
- set display scaling factor to 2
System Settings -> Display -> Scale for menu and title bars = 2
- run ./socket $(head -1 <(./plug))
-> blue GtkPlug is too small, it should cover all the black
- resize the window
-> at smaller sizes the scaling suddenly corrects itself, at larger ones it's wrong again
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: libgtk-3-0 3.18.9-1ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
Uname: Linux 4.4.0-18-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Apr 20 01:48:50 2016
SourcePackage: gtk+3.0
UpgradeStatus: No upgrade log present (probably fresh install)
build with:
gcc -o plug plug.c `pkg-config --cflags --libs gtk+-3.0`
gcc -o socket socket.c `pkg-config --cflags --libs gtk+-3.0`
run e.g. as:
./socket $(head -1 <(./plug))