Bug 476543

Summary: Wrong display sizes when Wayland fractional scaling enabled
Product: [Applications] krdc Reporter: David Warner <david.p.warner>
Component: VNCAssignee: Urs Wolfer <uwolfer>
Status: RESOLVED FIXED    
Severity: normal CC: aacid
Priority: NOR Keywords: wayland-only
Version First Reported In: 23.08.1   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description David Warner 2023-11-04 12:08:45 UTC
SUMMARY
When fractional scaling is enabled in the Wayland session, KRDC renders VNC connections in the wrong resolution. 100% or 200% scaling works correctly.

STEPS TO REPRODUCE
1. Run a VNC server on host (e.g. x11vnc on a machine with a display resolution of 1280x800).
2. Set monitor scaling on client to 125% or 150%.
3. Connect to host with KRDC.

OBSERVED RESULT
At 125% client monitor scaling, the 1280x800 host screen is rendered as 800x500.
At 150% client monitor scaling, the 1280x800 host screen is rendered as 960x600.

EXPECTED RESULT
The host screen should be rendered as 1280x800.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 5.27.9
KDE Frameworks Version: 5.111.0
Qt Version: 5.15.10

ADDITIONAL INFORMATION
Remmina, which I understand uses the same libVNCClient backend, has the 'opposite' problem - at 150% scaling, the 1280x800 host screen is rendered as 1920x1200.
Comment 1 David Warner 2024-06-20 10:02:48 UTC
This seems to be fixed in KRDC 24.05.0 and/or KDE Plasma 6.1.