Bug 408045

Summary: "Bit edit" checkboxes have uneven borders when desktop scaling is enabled
Product: [Applications] kcalc Reporter: Lastique <andysem>
Component: generalAssignee: Evan Teran <eteran>
Status: RESOLVED FIXED    
Severity: normal Keywords: junior-jobs
Priority: NOR    
Version: 18.12   
Target Milestone: ---   
Platform: Kubuntu   
OS: Linux   
Latest Commit: https://commits.kde.org/kcalc/895a9731984b071027d85dfd59e703acb35c467c Version Fixed In: 19.08.0
Attachments: KCalc with uneven Bit Edit checkbox borders

Description Lastique 2019-05-28 21:38:07 UTC 
SUMMARY
When desktop scaling is enabled, "Bit edit" checkboxes have uneven border widths. See attached screenshot.

STEPS TO REPRODUCE
1. Go to KDE System Settings -> Display and Monitor -> Scale Display.
2. Select scale factor greater than 1.0. I used 1.7.
3. Reboot.
4. Launch KCalc. Make sure it is in Numerical System Mode and Show Bit Edit is enabled.

OBSERVED RESULT
Bit edit checkboxes have borders of uneven width, as if scaled using nearest neighbour filter.

EXPECTED RESULT
The checkboxes should be drawn according to the scaling factor, not scaled post-drawing. This would result in a more uniform look of the checkboxes.

SOFTWARE/OS VERSIONS
Linux: Kubuntu 19.04
KDE Plasma Version: 5.15.4
KDE Frameworks Version: 5.56.0
Qt Version: 5.12.2
KCalc: 18.12.3
Comment 1 Lastique 2019-05-28 21:38:56 UTC 
Created attachment 120363 [details]
KCalc with uneven Bit Edit checkbox borders
Comment 2 Christoph Feck 2019-05-29 00:26:40 UTC 
Enabling antialiasing in BitButton::paintEvent() should give better rendering with fractional scaling.

https://cgit.kde.org/kcalc.git/tree/kcalc_bitset.cpp#n42
https://doc.qt.io/qt-5/qpainter.html#rendering-quality
Comment 3 Christoph Feck 2019-07-10 21:36:57 UTC 
Git commit 895a9731984b071027d85dfd59e703acb35c467c by Christoph Feck.
Committed on 10/07/2019 at 21:35.
Pushed by cfeck into branch 'master'.

Enable Antialiasing in bitset editor
FIXED-IN: 19.08.0

M  +1    -0    kcalc_bitset.cpp

https://commits.kde.org/kcalc/895a9731984b071027d85dfd59e703acb35c467c