Bug 491677

Summary:	Blurred icons when using fractional scaling (Qt 6.8, frameworks and plasma master)
Product:	[Frameworks and Libraries] frameworks-kiconthemes	Reporter:	Alex Fiestas <afiestas>
Component:	general	Assignee:	Christoph Feck <cfeck>
Status:	RESOLVED FIXED
Severity:	normal	CC:	jf.mundox, kdelibs-bugs, nate
Priority:	NOR
Version:	unspecified
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:	https://invent.kde.org/frameworks/kiconthemes/-/commit/89bbd78273f96a858ea181c977dda50f223cc4c4	Version Fixed In:	6.6
Sentry Crash Report:
Attachments:	Video where the blurry icons can be observed.

Description Alex Fiestas 2024-08-13 16:02:12 UTC

SUMMARY
While using latest Qt  6.8 + frameworks + plasma from master icons in Qt apps and some icons in plasma
are blurred as long as I have fractional scaling enabled.

STEPS TO REPRODUCE
1.  Enable fractional scaling
2. open kwrite
or
2. open a plasma popup

OBSERVED RESULT
Icons are blurry

EXPECTED RESULT
Icons should be sharp.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Arch, updated regularly.
KDE Plasma Version:  Master, compiled
KDE Frameworks Version:  Master, compiled
Qt Version: 6.8 from qt5.git branch

ADDITIONAL INFORMATION
I can patch and recompile if more information is needed.

Comment 1 Alex Fiestas 2024-08-13 16:13:24 UTC

Created attachment 172590 [details]
Video where the blurry icons can be observed.

Scaled down to 1080 from 4k but the icon blurriness can be observed.

Comment 2 Nate Graham 2024-08-13 16:37:52 UTC

I can't reproduce that with current git master for everything KDE, but Qt 6.7.2. At 100% or 150% scale on a 1080p screen, or 225% or 200% scale on a 4k screen, the icons don't exhibit the level of blurriness I can see in your screen recording.

Comment 3 Nate Graham 2024-08-13 16:49:11 UTC

Aha, apparently this is known and will be fixed with https://invent.kde.org/frameworks/kiconthemes/-/merge_requests/146.

Comment 4 Alex Fiestas 2024-08-13 17:49:58 UTC

Awesome, I can confirm that the patch fixes the issue for me.

Comment 5 Nicolas Fella 2024-08-14 14:08:04 UTC

*** Bug 491094 has been marked as a duplicate of this bug. ***

Comment 6 Nicolas Fella 2024-08-15 11:35:14 UTC

Git commit 89bbd78273f96a858ea181c977dda50f223cc4c4 by Nicolas Fella.
Committed on 14/08/2024 at 14:08.
Pushed by nicolasfella into branch 'master'.

[kiconengine] Adapt to Qt behavior change in scaledPixmap

Since Qt 6.8 the size we get doesn't include the scale,
so apply that outselves

M  +7    -1    src/kiconengine.cpp

https://invent.kde.org/frameworks/kiconthemes/-/commit/89bbd78273f96a858ea181c977dda50f223cc4c4