On 2/1/22 22:58, Vadim Galitsin wrote:
Hi guys,
I am currently looking to the issue with VirtualBox guest screen
resizing when guest is running Plasma on Wayland (using VMSVGA graphics
configuration).
For my experiments, I use Kubuntu 22.04 guest with Plasma 5.23. Guest
Additions are from our latest development build
(https://www.virtualbox.org/download/testcase/VBoxGuestAdditions_6.1.97-149665.iso).
In general, screen resizing does not work. If I, for example, drag
right-bottom corner of the guest window, I can see that guest screen
up-scales, but does not increase in size. So, it looks like a zoom-in
effect when image size stays the same.
For resizing on a guest side, we are using tool called VBoxDRMClient
(https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Additions/x11/VBoxClient/display-drm.cpp).
This tool receives resize hints from host and injects them into vmwgfx
driver using custom ioctl DRM_IOCTL_VMW_UPDATE_LAYOUT. This approach
works for X11 Desktop Environments as well as for Gnome3 on Wayland.
However, not for Plasma case.
What do you think if we could take a look to the issue from both sides?
If there is something in your mind what VBoxDRMClient is potentially
missing to have better integration with KDE/Plasma, we could discuss that.
Best regards,
Vadim
Hi,
There was some work in 5.23 to improve VM integration, but it looks like
there are still some issues.. As long as kwin_wayland receives a change
udev event after the vm window has been resized, kwin should re-scan drm
connectors, reload modes, and resize the workspace to match the new
output layout.
Relevant code is here
https://invent.kde.org/plasma/kwin/-/blob/749cf798ce465634b616682e7c072f0a43a22906/src/backends/drm/drm_backend.cpp#L254.
It's worth checking if kwin receives the relevant udev event.
Cheers,
Vlad
