Bug 427662

Summary: HiDPI Settings Not Working in Digikam 7.1.0
Product: [Applications] digikam Reporter: David R. Bergstein <david.r.bergstein>
Component: Usability-ErgonomyAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED FIXED    
Severity: normal CC: caulier.gilles, metzpinguin
Priority: NOR    
Version: 7.1.0   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed In: 7.2.0
Sentry Crash Report:

Description David R. Bergstein 2020-10-13 21:48:39 UTC 
SUMMARY


STEPS TO REPRODUCE
1. Launch digikam 7.1.0 on 4k display
2. Observe size of splash screen and resulting window
3. Text and graphics do not display correctly, i.e., too small

OBSERVED RESULT
Window text and graphics too small, should be scaled for 4k display per systemsettings display and monitor

EXPECTED RESULT
Proper scaling for 4k display of all text and graphics

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Linux (x86_64) release 5..4.0-48-generic
(available in About System)
KDE Plasma Version: 5.20.0
KDE Frameworks Version: 5.75.0
Qt Version: 5.15.0

ADDITIONAL INFORMATION
OS: KDE Neon 5.20
Comment 1 Maik Qualmann 2020-10-14 05:47:34 UTC 
This setting definitely works. Tested here under plasma and Windows. A scaling factor must be set in the system settings. Please post the output in a terminal from:

echo $QT_SCALE_FACTOR
echo $QT_SCREEN_SCALE_FACTORS

Maik
Comment 2 Maik Qualmann 2020-10-14 05:58:09 UTC 
You have read that these options in the digiKam system settings require a restart of digiKam?

Maik
Comment 3 David R. Bergstein 2020-10-14 11:54:15 UTC 
(In reply to Maik Qualmann from comment #1)
> This setting definitely works. Tested here under plasma and Windows. A
> scaling factor must be set in the system settings. Please post the output in
> a terminal from:
> 
> echo $QT_SCALE_FACTOR
> echo $QT_SCREEN_SCALE_FACTORS
> 
> Maik

dbergst@zenith:~$ echo $QT_SCALE_FACTOR

dbergst@zenith:~$ echo $QT_SCREEN_SCALE_FACTORS
DisplayPort-0=2;HDMI-A-0=2;DVI-D-0=2;
Comment 4 David R. Bergstein 2020-10-14 11:58:36 UTC 
(In reply to Maik Qualmann from comment #2)
> You have read that these options in the digiKam system settings require a
> restart of digiKam?
> 
> Maik

I was unable to locate these options in the digikam system settings.
Comment 5 Maik Qualmann 2020-10-14 11:59:51 UTC 
The scaling factors look good. Do you use the AppImage or Flatpak?

Maik
Comment 6 Maik Qualmann 2020-10-14 12:02:56 UTC 
HiDPI support must first be activated in digiKam. Under digiKam Settings-> Miscellaneous-> System.

Maik
Comment 7 David R. Bergstein 2020-10-14 12:05:08 UTC 
Ah, now I see.  The Miscellaneous Settings --> System has two settings that now have to be enabled, i.e., Use high DPI scaling from the screen factor and Use pixmaps with high DPI resolution.

After restarting, the DPI scaling works as expected.
Comment 8 Maik Qualmann 2020-10-14 12:07:09 UTC 
Great, thanks for the feedback.

Maik