Wayland

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Wayland is a protocol for a compositing window manager to talk to its clients, as well as a library implementing the protocol. It is supported on some desktop environments like GNOME and KDE. There is also a compositor reference implementation called Weston. XWayland provides a compatibility layer to seamlessly run legacy X11 applications in Wayland.

Requirements

Most Wayland compositors only work on systems using Kernel mode setting. Wayland by itself does not provide a graphical environment; for this you also need a compositor such as Weston or Sway, or a desktop environment that includes a compositor like GNOME or KDE.

For the GPU driver and Wayland compositor to be compatible they must support the same buffer API. There are two main APIs: GBM and EGLStreams.

Buffer API GPU driver support Wayland compositor support
GBM All except NVIDIA All
EGLStreams NVIDIA GNOME, KDE

Compositors

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Name Type Description
GNOME Stacking See GNOME#Starting.
sway Tiling Sway is an i3-compatible window manager for Wayland. GitHub
Enlightenment Stacking and tiling More Info
KDE Plasma Stacking See KDE#Starting Plasma
Orbment Tiling orbment (previously loliwm) is an abandoned tiling WM for Wayland.
Velox Tiling Velox is a simple window manager based on swc. It is inspired by dwm and xmonad.
Orbital Stacking Orbital is a Wayland compositor and shell (more akin to a WM than a DE) using Qt5 and Weston. The goal of the project is to build a simple but flexible and good looking Wayland desktop.
Liri Shell Stacking Liri Shell is the desktop shell for Liri, built using QtQuick and QtCompositor as a compositor for Wayland.
Maynard (Unclear) Maynard is a desktop shell client for Weston based on GTK. It was based on weston-gtk-shell, a project by Tiago Vignatti. Not under development. [1][2]
Motorcar (Unclear) Motorcar is a Wayland compositor to explore 3D windowing using virtual reality.
Way Cooler Tiling Way Cooler is a customizable (Lua config files) Wayland compositor written in Rust. Inspired by i3 and awesome.
Maze Compositor Floating 3D Maze Compositor is a 3D Qt based Wayland compositor
Cage Kiosk Cage is a Wayland compositor that displays a single fullscreen application
Greenfield Stacking Greenfield is a Wayland compositor that runs in a web browser and can display remote applications
Grefsen Floating Grefsen is a Qt/Wayland compositor providing a minimal desktop environment.
Waymonad Tiling Waymonad is a Wayland compositor based on ideas from and inspired by xmonad
wayfire Stacking Wayfire is a general purpose compositor.

Some of the above may support display managers. Check /usr/share/wayland-sessions/compositor.desktop to see how they are started.

Display managers

Below listed display managers which supports running Wayland compositors. The Type column indicates whether the display manager supports running on Wayland or not.

Name Type Description
GDM Runs on Wayland GNOME display manager.
LightDM Runs on X11 Cross-desktop display manager.
Ly Runs in console TUI display manager written in C
SDDM Runs on X11 QML-based display manager.

GUI libraries

See details on the official website.

GTK 3

The gtk3 package has the Wayland backend enabled. GTK will default to the Wayland backend, but it is possible to override it to Xwayland by modifying an environment variable: GDK_BACKEND=x11.

Qt 5

To enable Wayland support in Qt 5, install the qt5-wayland package.

To run a Qt 5 app with the Wayland plugin [3], use -platform wayland or QT_QPA_PLATFORM=wayland-egl environment variable. To force the usage of X11 on a Wayland session, use QT_QPA_PLATFORM=xcb.

Clutter

The Clutter toolkit has a Wayland backend that allows it to run as a Wayland client. The backend is enabled in the clutter package.

To run a Clutter app on Wayland, set CLUTTER_BACKEND=wayland.

SDL2

To run a SDL2 application on Wayland, set SDL_VIDEODRIVER=wayland.

Note: Many proprietary games come bundled with old versions of SDL, which don't support Wayland and might break entirely if you set SDL_VIDEODRIVER=wayland. To force the application to run with XWayland, set SDL_VIDEODRIVER=x11.

GLFW

To use GLFW with the Wayland backend, install the glfw-wayland package (instead of glfw-x11).

GLEW

To use GLEW with the Wayland backend, install the glew-wayland package (instead of glew).

EFL

EFL has complete Wayland support. To run a EFL application on Wayland, see Wayland project page.

Troubleshooting

Gamma

While Redshift doesn't support Wayland (without a patch) it is possible to apply the desired temperature in tty before starting a compositor. For example:

redshift -m drm -PO 3000

Otherwise some compositors feature this option during runtime:

LLVM assertion failure

If you get an LLVM assertion failure, you need to rebuild mesa without Gallium LLVM until this problem is fixed.

This may imply disabling some drivers which require LLVM. You may also try exporting the following, if having problems with hardware drivers:

$ export EGL_DRIVER=/usr/lib/egl/egl_gallium.so

Slow motion, graphical glitches, and crashes

Gnome-shell users may experience display issues when they switch to Wayland from X. One of the root cause might be the CLUTTER_PAINT=disable-clipped-redraws:disable-culling set by yourself for Xorg-based gnome-shell. Just try to remove it from /etc/environment or other rc files to see if everything goes back to normal.

Cannot open display: :0 with Electron-based applications

Make sure you haven't set GDK_BACKEND=wayland. Setting it globally will break Electron apps.

Screen recording

green-recorderAUR and obs-gnome-screencastAUR support screen recording on Wayland using GNOME screencast feature.

wf-recorder-gitAUR is a video recorder for wlroots-based compositors.

wlrobs-hgAUR is obs-studio plugin that allows you to screen capture on wlroots-based compositors.

Remote display

  • (20190503) wlroots (used by sway) offers an RDP backend since version 0.6 [4].
  • (20180401) mutter has now remote desktop enabled at compile time, see [5] and gnome-remote-desktop for details.
  • There was a merge of FreeRDP into Weston in 2013, enabled via a compile flag. The weston package has it enabled since version 6.0.0.
  • waypipe-gitAUR is a transparent proxy for Wayland applications, with a wrapper command to run over SSH

Input grabbing in games, remote desktop and VM windows

In contrast to Xorg, Wayland does not allow exclusive input device grabbing, also known as active or explicit grab (e.g. keyboard, mouse), instead, it depends on the Wayland compositor to pass keyboard shortcuts and confine the pointer device to the application window.

This change in input grabbing breaks current applications' behavior, meaning:

  • Hotkey combinations and modifiers will be caught by the compositor and won't be sent to remote desktop and virtual machine windows.
  • The mouse pointer will not be restricted to the application's window which might cause a parallax effect where the location of the mouse pointer inside the window of the virtual machine or remote desktop is displaced from the host's mouse pointer.

Wayland solves this by adding protocol extensions for Wayland and XWayland. Support for these extensions is needed to be added to the Wayland compositors. In the case of native Wayland clients, the used widget toolkits (e.g GTK, QT) needs to support these extensions or the applications themselves if no widget toolkit is being used. In the case of Xorg applications, no changes in the applications or widget toolkits are needed as the XWayland support is enough.

These extensions are already included in wayland-protocols, and supported by xorg-server-xwayland 1.20.

The related extensions are:

Supporting Wayland compositors:

Supporting widget toolkits:

  • GTK since release 3.22.18.

wlroots input inhibitor protocol

Input inhibitor is a Wayland protocol which was defined the by developers of Sway and wlroots and is overlapping Wayland's Compositor shortcuts inhibit protocol.
Sway and wlroots do not support the Compositor shortcuts inhibit and XWayland keyboard grabbing protocols, and it seems they are against adding support for the latter [6] [7].
No widget toolkit or application is known to support this protocol.

See also