Gamescope doesn't work with touch if nested

[ShapeShifter499]

Is there an existing issue for this?

• I have searched the existing issues

Are you using any gamescope patches or a forked version of gamescope?

• The issue occurs on upstream gamescope without any modifications

Current Behavior

When started as a nested session under a already running wayland session (I.E. started in the same session as Gnome) touchscreen events do not seem to work.

It does work in a gamescope-session just fine.

Steps To Reproduce

gamescope --default-touch-mode 4 -F fsr -S auto -f -W 1280 -H 800 -e --mangoapp -- steam -gamepadui -steamos3 -steampal -steamdeck -console

Attempt to touch elements in the steam client or any started games.

Nothing happens.

Hardware information

- Distro: Arch linux
- CPU: AMD Custom APU 0405
- GPU: Advanced Micro Devices, Inc. [AMD/ATI] VanGogh [AMD Custom GPU 0405]
- Driver Version: Mesa 24.2.5-arch1.1
Steam Deck LCD with Arch Linux replacing the original SteamOS

Software information

- Desktop environment: Gnome 47
- Session type: wayland
- Gamescope version: [gamescope] [Info]  console: gamescope version 3.15.13 (gcc 14.2.1)
- Gamescope launch command(s): gamescope --default-touch-mode 4 -F fsr -S auto -f -W 1280 -H 800 -e --mangoapp -- steam -gamepadui -steamos3 -steampal -steamdeck -console

Which gamescope backends have the issue you are reporting?

• Wayland (default for nested gamescope)
• DRM (default for embedded gamescope, i.e. gamescope-session)
• SDL
• OpenVR

Logging, screenshots, or anything else

No response

[matte-schwartz]

I am able to repro the issue on my own LCD Deck. It happens even if you drop off all the args so it doesn't seem to be a scaling issue to me... will try to dig into it when I have some time.

Happens on Plasma 6 wayland as well

[ShapeShifter499]

@matte-schwartz I wonder if this needs extra code to detect and translate the touches over. I don't know the code well but I'm just going off the experience of when firefox used to not work properly with touchscreens under wayland till they started adding in wayland support.

It's grabbing touches fine when it's allowed to be the main compositor. But something is lacking when it's nested.

[matte-schwartz]

You are exactly right, it's missing a wl_touch listener which is what grabs and translates those touch events.

I've been working on it here: https://github.com/matte-schwartz/gamescope/tree/wltouch but my implementation is still not fully functional. Main issue is it'll conflict touch movement with cursor movement, likely because of how I hooked up CWaylandPlane to the cursor plane incorrectly. Trying to make an equivelent touch plane was not going very well for me tbh...

I was planning on submitting it as a draft PR to get some review since I feel like I'm probably missing something very obvious, or Misyl will beat me to it and implement it properly 🐸

[ShapeShifter499]

@matte-schwartz maybe it's time to see if someone can lend a help?

[matte-schwartz]

Anyone is welcome to step in and submit a PR for this. I'm really not a developer, and my own attempt was broken in too many different ways to consider pull requesting.

[ShapeShifter499]

I wish I knew how to get this issue more attention. Still an issue.

[0x0015]

Just expressing my interest in this, as I'm also having this issue (using gamescope under sway on a dualscreen device, as gamescope cannot natively display on two screens).

[Patafix]

Same issue here

[Keyruu]

Same issue... I really wanted to Balatro on my Laptop, but without this it's just not as convenient.

[RegisAttila]

Sadly Same issue

[dra66y]

I also seem to have this issue. Using bazzite with the big screen session the touchscreen works great. But if I launch a game in a normal fedora 43 gnome or hyperland session no touch is passed to the game.

[DarkPhilosophy]

This is gold @matte-schwartz I try to build and install from your repo + fix issue but the game launch trasparent windows, touchscreen is working very badly when I clikc center of screen is touching edge of right-down aka buttom-left + in window mode there is a wide window title bar double my width of resolution