Created attachment 119556 [details] screenshot of mc after antialiasing change SUMMARY The commit ed5fa1f855a05ba82fe4f2f6d3ead803aa5eefdb introduced painter antialiasing which added unwanted black lines in programs like mc, iptraf-ng, etc, i.e. console applications with colored background when running with a scale factor e.g. 1.5. I would suggest to only use antialiasing in the painter when scaling is not activated until a real fix is there. Commenting out TerminalDisplay.cpp:1262 fixes the problem (but reintroduces #397985, so a real fix is needed), the line: paint.setRenderHint(QPainter::Antialiasing, _antialiasText); STEPS TO REPRODUCE 1. Set scale to 1.5 2. Start konsole 3. Run mc OBSERVED RESULT Black lines under every row EXPECTED RESULT A clean look SOFTWARE/OS VERSIONS KDE Plasma Version: 5.12.8 KDE Frameworks Version: 5.55.0 Qt Version: 5.9.7 Konsole master gives the result in the screenshot ADDITIONAL INFORMATION
This will probably fix it, but not provide antialiasing for hidpi displays: - paint.setRenderHint(QPainter::Antialiasing, _antialiasText); + if(qApp->devicePixelRatio() == 1.0) { + paint.setRenderHint(QPainter::Antialiasing, _antialiasText); + } But could be nice with a real fix.
It couldn't hurt to submit that as an RFC patch. :) You might get comments that could help with the cases that aren't yet covered. here's the documentation: https://community.kde.org/Infrastructure/Phabricator
I did this now in bug 373232, the important thing is the text aliasing anyways. Tested on hi-dpi, looks much better for me, but more artifacts at the border of painted regions are still there :/ *** This bug has been marked as a duplicate of bug 373232 ***