piano roll painting issue

[danboid]

I'm getting lots of bits of red lines when I'm editing the qtractor piano roll. They look like artefacts of the play head cursor and they gets worse when the play head is active.

I'm running the qtractor 0.9.31 package from the Debian Testing repos using gcc 12.2.0, Qt 6.4.2 and NVIDIA driver 515.86.01

Here is a video of what they look like:

qtr-draw.mp4

[danboid]

OK gh didn't like my video so I uploaded it to YT:

https://youtu.be/WH8Lxhp3Cqs

[rncbc]

the desktop screen seems scaled up; please try to cope with the exact native resolution first (1920x1080) then chose some other scale factor

[danboid]

Sorry Rui, I don't understand your suggestion. I am not using MATE's hidpi scaling if that's what you're suggesting is causing the problem.

[danboid]

I think I see what you mean now, Qt apps seem to be scaled. I think this might've been caused by me using qt5ct to try setting a dark mode in qt apps. I've tried setting it back to what I thought was the default although I currently still have the same issue.

How do I reset my qt settings?

[rncbc]

qt5ct should not interfere with qt6 apps anyhow

please check your desktop settings for a scaling factor being applied (eg. QT_SCALE_FACTOR > 1.0) or launch it from the command line as: QT_SCALE_FACTOR=1 /path/to/qtractor

[danboid]

OK this is a MATE specific bug as I don't have the problem when I run qtractor under XFCE. I've tried your suggestion and a couple of gsettings options but nothing has fixed it under MATE yet, qtractor (and qjackctl) insist on launching scaled.

[danboid]

dan@zbook:~$ gsettings get org.mate.interface window-scaling-factor-qt-sync
false
dan@zbook:~$ gsettings get org.mate.interface window-scaling-factor 
1

[danboid]

Thanks for your help Rui, lets punt this over to the MATE devs.

mate-desktop/mate-session-manager#302