[Linux][Wayland][GNOME/Mutter] Workaround for Native Pen/Touch Support coordinates misaligned with multiple displays

Aperta
  • Qualcosa non va?
#5,592 0 commenti 0 reazioni 0 assegnatari Vedi su GitHub

I maintainer di solito rispondono entro 1 giorno

Nessuno ha ancora preso questa issue.

Valutazione

Difficoltà
4/5
Tempo stimato
3-5 giorni
Idoneità per principianti
42/100
Tipo di issue
Bug
Chiarezza
Da chiarire
Stato di attività
Attiva
Stack tecnologico
cpp, linux
Ambito
desktop, operating-systems

Direzione di ricerca

Inizia riproducendo l’input nativo touchscreen su Linux Wayland con GNOME/Mutter e più display, utilizzando la configurazione XDG Portal Grab descritta. Confronta il comportamento delle coordinate prima e dopo l’assegnazione del touchscreen di Sunshine a un output con il comando GSettings documentato. Il lavoro è completo quando le coordinate touch corrispondono al display trasmesso senza richiedere una soluzione manuale specifica del sistema.

Scritto dal modello di indicizzazione a partire dal testo della issue.

Descrizione

Is there an existing issue for this?
  • I have searched the existing issues
Is your issue described in the documentation?
  • I have read the documentation
Is your issue present in the latest beta/pre-release?

This issue is present in the latest pre-release

Describe the Bug

By default on GNOME/Mutter running Wayland, native touchscreen input from Moonlight can be spatially misaligned when multiple displays are connected.

The issue is not specific to Mutter virtual monitors. I encountered it while streaming to a Mutter virtual monitor and XDG Portal Grab, I had previously experienced the same touchscreen misalignment with a physical display created using a dummy HDMI/DP adapter and KMS capture.

Expected Behavior

Touch input should be mapped to the display being streamed, with the touch coordinates corresponding to the same physical/logical positions shown by Moonlight.

With multiple displays connected, touch input should not be offset or interpreted relative to another display.

Additional Context

here is a confirmed workaround on GNOME/Mutter that fixes the touchscreen alignment.

Mutter has a per-device touchscreen output setting that can explicitly associate a touchscreen with a specific display.

For example, on my system:

gsettings set \
  'org.gnome.desktop.peripherals.touchscreen:/org/gnome/desktop/peripherals/touchscreens/1209:0004/' \
  output "['MetaVendor', 'MetaVirtualMonitor', '0x00']"

After assigning the Sunshine touchscreen to the correct output, native touch coordinates from Moonlight are correctly aligned with that display.

The device ID and output tuple are system-specific. The values above correspond to my setup; physical displays will have their own output identity. For example, my Mutter virtual monitor exposes:

['MetaVendor', 'MetaVirtualMonitor', '0x00']

The important part is the explicit association between the Sunshine touchscreen and the output being streamed.

This also indicates that the issue is not inherently caused by virtual displays. I have reproduced the same touchscreen misalignment with a physical display created through a dummy HDMI/DP adapter and KMS capture. The common factor is having multiple outputs while using absolute/native touchscreen input.

The touchscreen itself appears to provide usable absolute coordinates; explicitly changing the Mutter output association changes the coordinate mapping and fixes the problem.

I am not suggesting that Sunshine necessarily needs to implement this exact GSettings mechanism. The purpose of this report is to document the confirmed GNOME/Mutter workaround and provide a concrete lead for determining where the appropriate long-term fix belongs.

There are also reports of similar multi-display touchscreen issues under other Wayland compositors, including KDE Plasma/KWin, but I have not independently verified an equivalent fix there, so I am not making a claim about the KDE implementation.

The main confirmed finding here is:

On GNOME/Mutter Wayland, explicitly mapping the Sunshine touchscreen device to the intended output fixes native touchscreen misalignment with multiple displays.

Host Operating System

Linux

Operating System Version

Arch Linux

Architecture

other, n/a

Package

Linux - flathub/flatpak

GPU Type

n/a

GPU Model

n/a

GPU Driver/Mesa Version

n/a

Capture Method

XDG Portal Grab (FreeBSD/Linux)

Apps
Log output
Online logs

No response

Lingua principale
C++
Stelle
43k
Fork
2.4k
Merge medio
1g 15h
PR unite (30g)
105

Preparare l'ambiente

Come iniziare

  1. Leggi tutta la issue e poi la guida ai contributi del progetto.
  2. Commenta sulla issue per dire che te ne occupi tu — evita che due persone facciano lo stesso lavoro.
  3. Fai un fork del repository e lavora su un branch.
  4. Apri una pull request che faccia riferimento al numero della issue.

Altre issue di LizardByte/Sunshine

Tutte le issue di LizardByte/Sunshine

Issue simili

Altre issue su C++

Ricevi le nuove issue nella tua casella

Un breve riepilogo di issue GitHub adatte ai principianti.