Arch Linux

PeerK

Member

Registered: 2020-06-24

Posts: 40

KDE Wayland, how to flip/reflect display?

Hi everyone,

since I always read, that KDE/Wayland is getting more and more robust, I gave it a try. And yes: It works pretty stable and complete :)

But I have a problem with my monitor-setup and maybe someone may have an idea, how to get rid of it.

I have 4 displays, one of them is a (self-made) teleprompter. That display needs to be mirrored. With X11, I configured the displays in the following way:

xrandr \
  --output HDMI-A-1 --mode 2560x1440 --pos 0x0 --transform 1,0,0,0,-1,1440,0,0,1 \
  --output DP-1 --mode 5120x2160 --pos 2580x720 --rotate inverted --primary \
  --output DP-2 --mode 2560x1440 --pos 7720x0 --rotate left \
  --output HDMI-A-2 --mode 1920x1080 --pos 5140x2900 --rotate normal

The display "HDMI-A-1" is the teleprompter and the transform-options do the mirroring.

With Wayland, the transform-option throws an error (X Error of failed request:  BadValue (integer parameter out of range for operation)) and seem not to exist any more. Therefore I played around with xrandr and this solution doesn't throw an error - but doesn't mirror the teleprompter display as well :(

xrandr \
  --output HDMI-A-1 --mode 2560x1440 --pos 0x0 --reflect x \
  --output DP-1 --mode 5120x2160 --pos 2580x720 --rotate inverted --primary \
  --output DP-2 --mode 2560x1440 --pos 7720x0 --rotate left \
  --output HDMI-A-2 --mode 1920x1080 --pos 5140x2900 --rotate normal

I tried to install some wayland-tools, but

• wlr-randr-git quits with "compositor doesn't support wlr-output-management-unstable-v1" and

• way-displays quits with "compositor does not support WLR output manager protocol"

My question: Does anybody have an idea, how to flip the HDMI-A-1 under Wayland?

Thanks and kind regards :),
Peer

Specs:

System:
  Host: ******* Kernel: 6.5.4-arch2-1 arch: x86_64 bits: 64
    Desktop: KDE Plasma v: 5.27.8 Distro: Arch Linux
Machine:
  Type: Desktop System: Micro (HK) Tech product: HX90G v: N/A
    serial: <superuser required>
  Mobo: Shenzhen Meigao Equipment model: HX90G serial: <superuser required>
    UEFI: American Megatrends LLC. v: 5.19 date: 08/12/2022
CPU:
  Info: 8-core AMD Ryzen 9 5900HX with Radeon Graphics [MT MCP] speed (MHz):
    avg: 945 min/max: 400/4680
Graphics:
  Device-1: AMD Navi 23 [Radeon RX 6600/6600 XT/6600M] driver: amdgpu
    v: kernel
  Device-2: AMD Cezanne [Radeon Vega Series / Radeon Mobile Series]
    driver: amdgpu v: kernel
  Display: wayland server: X.org v: 1.21.1.8 with: Xwayland v: 23.2.1
    compositor: kwin_wayland driver: X: loaded: amdgpu
    unloaded: modesetting,vesa dri: radeonsi gpu: amdgpu,amdgpu resolution:
    1: 5120x2160 2: 1440x2560 3: 2560x1440 4: 1920x1080
  API: OpenGL v: 4.6 Mesa 23.1.8-arch1.1 renderer: AMD Radeon RX 6600M
    (navi23 LLVM 16.0.6 DRM 3.54 6.5.4-arch2-1)

Last edited by PeerK (2023-09-22 18:00:59)

seth

Member

Registered: 2012-09-03

Posts: 61,606

Re: KDE Wayland, how to flip/reflect display?

Forget about using xrandr for any of this, it operates on xwayland and is maybe picked up by the wayland compositor, maybe not.
You'll need kwin_wayland to support such feature, https://www.reddit.com/r/kde/comments/1 … h_wayland/ looks promising.

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PeerK

Member

Registered: 2020-06-24

Posts: 40

Re: KDE Wayland, how to flip/reflect display?

Forget about using xrandr for any of this, it operates on xwayland and is maybe picked up by the wayland compositor, maybe not.
You'll need kwin_wayland to support such feature, https://www.reddit.com/r/kde/comments/1 … h_wayland/ looks promising.

Thank you very much!

Starting with your hint, I found - unfortunately -, that a "flipped transformation" seems to be not implemented in Wayland, yet:

https://invent.kde.org/plasma/libkscree … heads#L107

So I will have to roll back to x11 and I am going to make a note here, when kwayland is being updated with this feature.

Kind regards,
Peer

Last edited by PeerK (2023-09-22 22:01:14)

PeerK

Member

Registered: 2020-06-24

Posts: 40

Re: KDE Wayland, how to flip/reflect display?

Just for completeness:

I opened a topic

"kwayland/kscreen: Flip/mirror screen impossible yet" (https://discuss.kde.org/t/kwayland-kscr … e-yet/5857)

on https://discuss.kde.org and I am willing to sponsor a part of the development.

If anybody is interested in the development too: Feel invited

Kind regards,
Peer

Last edited by PeerK (2023-10-07 20:51:42)