bug#52492: [PATCH 0/7] Improve screen sharing support under Wayland

[Mathieu Othacehe <othacehe@gnu.org>]

Hey Josselin,

Thanks for working on that. I fixed a few minor details and pushed the
series.

> I can get screensharing working in icecat on sway by manually starting
> pipewire then wireplumber (and then xdg-desktop-portal-wlr followed by
> xdg-desktop-portal if they're not installed in your profile, otherwise
> your user DBus session will launch them automatically), and starting
> icecat with

As discussed on #guix, we may need to find a way to start those services
automatically.

> since the pipewire library is dlopened by libwebrtc rather than
> statically or dynamically linked.  We could possibly add this to the
> icecat package, as it has a wrapper doing a similar thing for other
> libraries.

Seems fair.

I also tried to run obs, this way:

--8<---------------cut here---------------start------------->8---
QT_QPA_PLATFORM=wayland obs
--8<---------------cut here---------------end--------------->8---

was prompted for a screen/window to capture using pipewire, but then I
have the following error, does that ring a bell?

--8<---------------cut here---------------start------------->8---
info: ------------------------------------------------
info: Loaded scenes:
info: - scene 'Scene':
info:     - source: 'Window Capture (PipeWire)' (pipewire-window-capture-source)
info: ------------------------------------------------
qt.qpa.wayland: Wayland does not support QWindow::requestActivate()
info: [pipewire] available cursor modes:
info: [pipewire]     - Metadata
info: [pipewire]     - Always visible
info: [pipewire]     - Hidden
Attempted path: share/obs/obs-studio/images/overflow.png
Attempted path: /gnu/store/1fp8wl9y2i72ld59d1spw85xvw9l88ws-obs-27.0.1/share/obs/obs-studio/images/overflow.png
info: [pipewire] screencast session created
info: [pipewire] asking for window…
info: adding 42 milliseconds of audio buffering, total audio buffering is now 42 milliseconds (source: Mic/Aux)

warning: [pipewire] Failed to start screencast, denied or cancelled by user
info: PipeWire initialized (sender name: 1_1734)
info: User added source 'Screen Capture (PipeWire)' (pipewire-desktop-capture-source) to scene 'Scene'
info: [pipewire] available cursor modes:
info: [pipewire]     - Metadata
info: [pipewire]     - Always visible
info: [pipewire]     - Hidden
info: [pipewire] screencast session created
info: [pipewire] asking for desktop…
warning: [pipewire] Failed to start screencast, denied or cancelled by user
^Cinfo: ==== Shutting down ==================================================
--8<---------------cut here---------------end--------------->8---

Thanks,

Mathieu