Bug 432974

Summary: Tilted view of remote desktop
Product: [Applications] krfb Reporter: Jaggz H. <jaggz.h>
Component: generalAssignee: George Goldberg <grundleborg>
Status: REPORTED ---    
Severity: major    
Priority: NOR    
Version First Reported In: 20.12.2   
Target Milestone: ---   
Platform: Debian testing   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Slanted remote vnc desktop

Description Jaggz H. 2021-02-15 15:03:19 UTC
Created attachment 135701 [details]
Slanted remote vnc desktop

SUMMARY
Nearly all [older?] clients display the remote system "slanted".

STEPS TO REPRODUCE
1. Using built in Desktop Sharing (with unattended access, if that matters)
2. Connect from almost any older client. (Using KRDC from Debian stable reproduces this for me for instance, when connecting to the Debian Testing system.)
  2b. KRDC in Debian TESTING seems to be working (when I krdc back to myself), so it seems there's some compatibility issue.

OBSERVED RESULT
[Slanting: See screenshot]
  Each line seems 1 or more pixels shifted to the left.
[Scale] xtigervncviewer (from Deb-Stable) refuses to scale, as do some other clients. I have tested this only with a few and don't have good data on it right now.  Though sloped, scaling does seem to be working with krdc(stable) -> krfb (testing)

EXPECTED RESULT
:) Display should be rectangle'ish, not parallelogram'ish :)


SOFTWARE/OS VERSIONS
Linux Debian Testing/Bullseye
KDE Plasma: (There's no "About System" now. It's "System Information" right?)
KDE Plasma Version: 5.20.5
KDE Frameworks Version: 5.78.0
QT Version: 5.15.2
Qt Version: ?

ADDITIONAL INFORMATION
Android VNC viewer (from RealVNC) works. In debian-stable, the only client I've found, that doesn't cause the tilt, is xtigervncviewer.

nVidia card and driver:
The card is an old nVidia GeForce GTX 560 Ti
Official nvidia non-free LEGACY drivers from debian testing:
  nvidia-legacy-390xx-driver
nvidia-settings says nvidia driver version: 390.141
(linux x86_64)