Bug 483393

Summary: Icons rendered with Kirigami.Icon are kind of blurry in Plasma 6 with 1.5 scale factor
Product: [Frameworks and Libraries] frameworks-kirigami Reporter: zvova7890
Component: generalAssignee: kdelibs bugs <kdelibs-bugs-null>
Status: RESOLVED INTENTIONAL    
Severity: normal CC: materka, me, nate, notmart
Priority: NOR Keywords: qt6
Version First Reported In: 6.0.0   
Target Milestone: 1.0   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description zvova7890 2024-03-13 00:58:13 UTC 
SUMMARY
Plasma 5 had crystal clear icons in the system tray in an X11 session using 1.5 scale factor. Now it is blurred in both X11 and Wayland sessions. With a 2x scale, it looks way better, and it feels like it is not upscaled/downscaled.


STEPS TO REPRODUCE
1. Use Plasma 6
2. Use 1.5 scale factor
3. Look at the systray icons

OBSERVED RESULT
Blurred icons in systray.

EXPECTED RESULT
Crystal clear icons in systray.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.0.1
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2
Kernel Version: 6.7.9-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 9 7940HS w/ Radeon 780M Graphics
Memory: 28,2 GiB of RAM
Graphics Processor: AMD Radeon Graphics
Manufacturer: Micro Computer (HK) Tech Limited
Product Name: Venus series
Comment 1 Nate Graham 2024-03-13 22:16:55 UTC 
The icons were crystal clear in Plasma 5 only because we weren't scaling them at all--which was its own bug that other people sensitive to *that* complained about. :) Now we're scaling everything to preserve the intended size relationships between items, and we get complaints about blurriness with fractional scales and low to moderate DPI screens! Sometimes you just can't win. :p

I'm afraid there's very little we can do here. A certain amount of blurriness has to be expected when using a fractional scale factor. See https://community.kde.org/Get_Involved/Design/Frequently_Discussed_Topics#Pixel-alignment_for_SVG_icons to understand why.
Comment 2 zvova7890 2024-03-14 03:34:20 UTC 
Nate, well yeah, thanks for the detailed explanations :)

I'm understand concept. But I have fillings that in case of the systray it is not just about "a half of the pixel" problem. Because it looks too blurry for that explanation. 

Every time I look at the systray, I think that my vision has deteriorated so much that I need to start using glasses at the computer :-D 
Anyway, I will do some experiments with that when I have the time, because it got me interested :)
Comment 3 Nate Graham 2024-03-14 16:32:05 UTC 
You're welcome!

Despite my response and my having closed this bug report, I can tell you that the issue irks me too, and I'm very open to alternative approaches that are technically feasible within the scope of using Qt scaling. For example, we could perhaps investigate better scaling algorithms in KWin.