Created attachment 112533 [details] Garbled fonts in Digital Clock settings In the Plasma widget settings, the dialog window contains badly rendered fonts. This is not specific to any particular widget. For example, see the attached screenshot for Digital Clock settings (right-click on the Digital Clock widget on the panel, click on "Digital Clock Settings"). You can see on the screenshot that the fonts on the window title, buttons and other controls are rendered properly. So are the other fonts in the system. The problem is with the fonts used in the window contents. The fonts don't get fixed on window resizes or switching to another tab. Kubuntu 18.04, Plasma 5.12.4.
Created attachment 112534 [details] Garbled fonts in Updater settings
Known issue in QtQuick not working correctly with HiDPI. If this still does not work correctly with Qt 5.11, please report this issue directly to Qt developers via https://bugreports.qt.io/
Was this problem reported to Qt previously? Could you provide a reference to that bug report?
I didn't find a Qt bug reference, but based comment #2 on bug 393724 comment #1.
Bug 393724 reporter mentions that he is using UI scaling. In my case UI scaling is not used (i.e. the scale factor is 1.0). I only set "Xft.dpi: 162" in ~/.Xresources to make fonts look larger. Are you sure this bug is the same? Also, note that font corruption is only visible in Plasma widget settings and nowhere else in the system, including applications, KDE or not.
Also, the Desktop Theme page in the System Settings that is used to illustrate the problem in bug 393724 is rendered correctly on my system, no blurry fonts.
The Qt bug that David was talking about is https://bugreports.qt.io/browse/QTBUG-67007. But looking at the screenshots posted in this bug, I'm not sure it's the same issue. The rendering glitches you're experiencing aren't blurriness, but rather clipped tops and mis-aligned middles. It's probably still a Qt bug, but a different one. That said, using Qt scaling is the recommended method of accomplishing your goal rather than changing the font DPI. What you're doing isn't something we explicitly support or have a lot of eyeballs on.
Thanks for the link. I would say, the fonts in this bug report look like a result of a nearest neighbour scaling, although there shouldn't be any scaling at all. > That said, using Qt scaling is the recommended method of accomplishing your goal rather than changing the font DPI. UI scaling produces much more graphical issues than the DPI setting.
Then we need to fix those bugs! :) What have you found to be the problem children so far?
<offtopic> Some of the bugs you know already ;). These are the showstoppers for me: https://bugs.kde.org/show_bug.cgi?id=373232 https://bugs.kde.org/show_bug.cgi?id=388217 Most of the work I do is from Yakuake, so it not working properly is critical for me. There are minor ones like https://bugs.kde.org/show_bug.cgi?id=388218 I can also see that the Logout/Reboot/Shutdown UI is rendered rather poorly (again, as if scaled with the nearest neighbour method) when UI scaling is enabled. I don't think I reported this one - mostly because I can't take a screenshot and didn't have time. But given the problems with Konsole/Yakuake I didn't test too much to discover more issues and settled with my current solution. </offtopic>
For the reference, I created Qt bug: https://bugreports.qt.io/browse/QTBUG-68606
Thanks! I'll see about those HiDPI bugs you mentioned.
Thank you, Nate.
I got a new computer and see this exact behavior (this may be related to newer intel processors, I suppose). Unfortunately there's no upstream activity at all... [Note that, like the OP, I'm continuously testing HiDPI, but unfortunately HiDPI with fractional scaling has other issues that IMO are far more annoying than this one.]
(In reply to avlas from comment #14) > I got a new computer and see this exact behavior (this may be related to > newer intel processors, I suppose). Unfortunately there's no upstream > activity at all... > > [Note that, like the OP, I'm continuously testing HiDPI, but unfortunately > HiDPI with fractional scaling has other issues that IMO are far more > annoying than this one.] I see the issue in KDE neon User Edition (Qt 5.12.0 / Plasma 5.15.3 / KF5 5.56)