Blurry icons with Qt in hidpi

[kybos]

Version

Double Commander
Version: 1.2.1 beta
Revision: 145
Commit: 7f6ab71
Build: 2026/01/26
Lazarus: 4.4.0.0
Free Pascal: 3.2.2
Platform: x86_64-Linux-qt6
System: Manjaro Linux
Desktop Environment: KDE (wayland)
Widgetset library: Qt 6.10.1

Description

All icons are blurry/pixelated in both the Qt5 and Qt6 versions (hidpi scaling is 200%):

Internal Editor:

This is even true for SVG icons (when set explicitly for a custom action).

It's not the case with the GTK version on Mint/Cinnamon (same PC, same scaling):

[alexx2000]

I added high DPI support in DC 1.2.3 for Qt6+Wayland.

[kybos]

Thank you very much.
As the snapshots (appimage) are apparently only available for Qt5, I will test this when the new version becomes available in Manjaro.

[kybos]

The main toolbar and the file icons in the file list are now sharp indeed.
There are some elements that are still blurry.

Options dialog:

Options dialog buttons:

Internal editor toolbar (same for Compare Files):

The (optional) icons in the menus are not quite sharp (but apparently not quite as blurry as the rest):

(As is also obvious from the screenshot, some icons are not suited for dark backgrounds.)

[alexx2000]

Options dialog:

Unfixable, I don't have a High DPI icons for this place. Maximum that I can do is to disable icons there.

Internal editor toolbar (same for Compare Files):

These icons should be sharp too. Do you have one monitor?

[kybos]

Yes, I have one 4k monitor.

[kybos]

Unfixable, I don't have a High DPI icons for this place. Maximum that I can do is to disable icons there.

Please don't disable the icons in the Options, they are quite helpful, giving additional orientation. As the icons are small there, the issue is not so critical. Maybe someone (me? ;-) ) will find time to provide hi-res version of the icons in the future.

Just for reference, the icons in the Viewer are blurry as well:

[alexx2000]

Just for reference, the icons in the Viewer are blurry as well:

This is a very strange. I tested Viewer/Editor/Differ under Arch Linux, KDE (wayland) with scaling and I don't have this problem.

[kybos]

These icons are obviously coming from the system/desktop, not the internal dctheme. I will do some more testing.

Is there any documentation on how exactly the icons are being selected at runtime, depending on resolution, area etc.? Or maybe a code part that a non-Pascal person could possibly understand?