Portals in fht-compositor

XDG desktop portals are a core component of any Wayland desktop session. They allow user programs and applications to interact with other components of the system (like the compositor) in a safe and secure way through D-Bus.

The default recommended portal for fht-compositor desktop sessions is xdg-desktop-portal-gtk, it provides all the basics needed (file picker, accounts, settings, etc.). gnome-keyring can be added to have Secrets portal support (needed for programs like Fractal or Secrets)

In addition, fht-compositor provides additional portals that need a session-specific implementation.

Setting up fht-compositor XDG desktop portal.

AUR package/Nix module

• If you are using fht-compositor through the NixOS/home-manager modules or the fht-compositor package, this should have already been sorted out for you!
• If you are using the AUR package, this should also be sorted out for you!

Install the following files in the relevant places

File	Target path
res/fht-compositor.portal	/usr/share/xdg-desktop-portal/portals/
res/fht-compositor-portals.conf	/usr/share/xdg-desktop-portal/

The compositor itself should start up the portal after initializing graphics (IE starting up outputs).

XDG ScreenCast portal

The XDG screencast portal is used by applications that request casting/recording a screen or part of a screen. Example programs include OBS and web browsers (through WebRTC).

You can chose between three options:

• Screencast an entire monitor
• Screencast a workspace: It will include only the workspace windows, not any layer shells
• Screencast a window: The window itself with additional popups will be screencasted

The screencasts are damage-tracked, IE. new frames will be pushed and drawed only when something changes. Moreover, only DMABUF-based screencasting is supported, as SHM is way too slow. If that is needed, use the wlr-screencopy protocol.

Using this portal will require an additional dependency, fht-share-picker, it is required to select which source (from the above) to screen cast.

If you are using the Nix module, this should be installed if you compile fht-compositor with default attrs. Otherwise, make sure to use a package with withXdgScreenCast set to true, like so:

fht-compositor.override { withXdgScreenCast = true; /* other attrs */ }