Wayland - ArchWiki

# 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

Name | Type | Description
--- | --- | ---
Mutter | Stacking | See GNOME#Starting.
sway | Tiling | Sway is an i3-compatible window manager for Wayland. GitHub
Enlightenment | Stacking and tiling | See Enlightenment#Manually. More Info: [1] [2]
KDE Kwin | 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 compositor and shell (more of a WM than a DE) using Qt5 and Weston. The goal is to build a simple but flexible and good looking 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. [3][4]
Motorcar | (Unclear) | Motorcar is a Wayland compositor to explore 3D windowing using virtual reality.
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.
Weston | Floating | Weston is a Wayland compositor reference implementation.

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.
greetd | Login daemon | Minimal and flexible login daemon.

## 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 application with the Wayland plugin [5], use `-platform wayland` or `QT_QPA_PLATFORM=wayland` environment variable. To force the usage of X11 on a Wayland session, use `QT_QPA_PLATFORM=xcb`. This might be necessary for some proprietary applications that do not use the system's implementation of Qt, such as zoomAUR.

On some compositors, for example sway, Qt applications running natively might have missing functionality. For example, KeepassXC will be unable to minimize to tray. This can be solved by installing qt5ct and setting `QT_QPA_PLATFORMTHEME=qt5ct` before running the application.

### 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 application 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.

### winit

Winit is window handling library in Rust. It will default to the Wayland backend, but it is possible to override it to Xwayland by modifying an environment variable: `WINIT_UNIX_BACKEND=x11`.

## Troubleshooting

### Gamma

This article or section is a candidate for merging with Backlight#Color correction.

Notes: Same topic. (Discuss in Talk:Wayland#)

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:

- On GNOME, the built-in Night Light can be used.
- On KDE Plasma, the built-in KDE#Night Color can be used.
- On Sway 1.0 and other wlroots-based compositors, as well as Orbital, redshift-wayland-gitAUR/redshift-wlr-gamma-control-gitAUR can be used (the two AUR packages are the same).

### 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.

### Remote display

- (20200206) wlroots (used by sway) offers an VNC backend via wayvncAUR since version 0.10. RDP backend has been removed. [6].
- (20180401) mutter has now remote desktop enabled at compile time, see [7] 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:

- XWayland keyboard grabbing protocol
- Compositor shortcuts inhibit protocol
- Relative pointer protocol
- Pointer constraints protocol

Supporting Wayland compositors:

- Mutter, GNOME's compositor since release 3.28
- wlroots supports relative-pointer and pointer-constraints

Supporting widget toolkits:

- GTK since release 3.22.18.

## See also

- Article about Wayland debugging on Fedora Wiki
- Cursor themes
- Arch Linux forum discussion
- Wayland documentation online
- Awesome Wayland projects

Category:

- Graphical user interfaces

Hidden category:

- Pages or sections flagged with Template:Merge