Wayland: Difference between revisions

Latest revision as of 17:13, 22 April 2024

Wayland is a display server protocol. It is aimed to become the successor of the X Window System. You can find a comparison between Wayland and Xorg on Wikipedia.

Display servers using the Wayland protocol are called compositors because they also act as compositing window managers. Below you can find a list of Wayland compositors.

For compatibility with native X11 applications to run them seamlessly, Xwayland can be used, which provides an X Server 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 (see the following section), or a desktop environment that includes a compositor (e.g. GNOME or Plasma).

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 < 495*	All
EGLStreams	NVIDIA	GNOME

* NVIDIA ≥ 495 supports both EGLStreams and GBM.[1]

Since NVIDIA introduced GBM support, many compositors (including Mutter and KWin) started using it by default for NVIDIA ≥ 495. GBM is generally considered better with wider support, and EGLStreams only had support because NVIDIA did not provide any alternative way to use their GPUs under Wayland with their proprietary drivers. Furthermore, KWin dropped support for EGLStreams after GBM was introduced into NVIDIA.

If you use a popular desktop environment/compositor and a GPU still supported by NVIDIA, you are most likely already using GBM backend. To check, run journalctl -b 0 --grep "renderer for". To force GBM as a backend, set the following environment variables:

GBM_BACKEND=nvidia-drm
__GLX_VENDOR_LIBRARY_NAME=nvidia

Compositors

See Window manager#Types for the difference between Tiling and Stacking.

Tiling

Cagebreak — Based on cage, inspired by ratpoison.

https://github.com/project-repo/cagebreak || cagebreak^AUR

dwl — dwm-like Wayland compositor based on wlroots.

https://codeberg.org/dwl/dwl || dwl^AUR

Hyprland — A dynamic tiling Wayland compositor that does not sacrifice on its looks.

https://hyprland.org || hyprland

japokwm — Dynamic Wayland tiling compositor based around creating layouts, based on wlroots.

https://github.com/werererer/japokwm || japokwm-git^AUR

newm — Wayland compositor written with laptops and touchpads in mind (currently unmaintained).

https://github.com/jbuchermn/newm/ || newm-git^AUR

niri — A scrollable-tiling Wayland compositor.

https://github.com/YaLTeR/niri/ || niri^AUR

Polonium — A spiritual successor of Bismuth for tiling windows on KDE 6.

https://github.com/zeroxoneafour/polonium || kwin-polonium^AUR

Qtile — A full-featured, hackable tiling window manager and Wayland compositor written and configured in Python.

https://github.com/qtile/qtile || qtile

river — Dynamic tiling Wayland compositor inspired by dwm and bspwm.

https://codeberg.org/river/river || river

Sway — i3-compatible Wayland compositor based on wlroots.

https://github.com/swaywm/sway || sway

SwayFx — Sway, but with eye candy!

https://github.com/WillPower3309/swayfx || swayfx^AUR

Velox — Simple window manager based on swc, inspired by dwm and xmonad.

https://github.com/michaelforney/velox || velox-git^AUR

Vivarium — A dynamic tiling Wayland compositor using wlroots, with desktop semantics inspired by xmonad.

https://github.com/inclement/vivarium || vivarium-git^AUR

Stacking

Enlightenment — See Enlightenment#Manually. More Info: [2] [3]

https://www.enlightenment.org/ || enlightenment

hikari — wlroots-based compositor inspired by cwm which is actively developed on FreeBSD but also supports Linux.

https://hikari.acmelabs.space/ || hikari^AUR

KDE KWin — See KDE#Starting Plasma.

https://userbase.kde.org/KWin || kwin

Liri Shell — Part of Liri, built using QtQuick and QtCompositor as a compositor for Wayland.

https://github.com/lirios/shell || liri-shell-git^AUR

labwc — wlroots-based compositor inspired by Openbox.

https://github.com/labwc/labwc || labwc-git^AUR

Mutter — See GNOME#Starting.

https://gitlab.gnome.org/GNOME/mutter || mutter

wayfire — 3D compositor inspired by Compiz and based on wlroots.

https://wayfire.org/ || wayfire^AUR

Weston — Wayland compositor designed for correctness, reliability, predictability, and performance.

https://gitlab.freedesktop.org/wayland/weston || weston

wio — wlroots-based compositor that aims to replicate the look and feel of Plan 9's Rio desktop.

https://gitlab.com/Rubo/wio || wio-wl^AUR

Other

Cage — Displays a single fullscreen application like a kiosk.

https://www.hjdskes.nl/projects/cage/ || cage

nwg-shell — A GTK-based shell for sway and Hyprland Wayland compositors.

https://github.com/nwg-piotr/nwg-shell || nwg-shell^AUR

kiwmi — A fully programmable Wayland Compositor.

https://github.com/buffet/kiwmi || kiwmi-git^AUR

phoc — A tiny wlroots-based compositor for mobile devices.

https://gitlab.gnome.org/World/Phosh/phoc || phoc

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

Display managers

Display managers listed below support launching Wayland compositors.

Name	Runs itself on Wayland?	Description
emptty^AUR	No	Simple CLI Display Manager on TTY.
GDM	Yes	GNOME display manager.
greetd	When using a Wayland greeter	Minimal and flexible login daemon.
lemurs^AUR	No	TUI display manager written in Rust.
LightDM	No	Cross-desktop display manager.
Ly	No	TUI display manager written in C
SDDM	Yes	QML-based display manager.
tbsm	No	Simple CLI session launcher written in pure bash.
uwsm^AUR	No	Session and XDG autostart manager for standalone compositors leveraging Systemd mechanisms.

Xwayland

Xwayland is an X server that runs under Wayland and provides compatibility for native X11 applications that are yet to provide Wayland support. To use it, install the xorg-xwayland package.

Xwayland is started via a compositor, so you should check the documentation for your chosen compositor for Xwayland compatibility and instructions on how to start Xwayland.

Note:

Security: Xwayland is an X server, so it does not have the security features of Wayland
Performance: Xwayland has a nearly identical performance to that of X11. In some cases you might notice degraded performance, especially on NVIDIA cards.
Compatibility: Xwayland is not fully backward compatible with X11. Some applications may not work properly under Xwayland.

NVIDIA driver

Note: NVIDIA drivers prior to version 470 (e.g. nvidia-390xx-dkms^AUR) do not support hardware accelerated Xwayland, causing non-Wayland-native applications to suffer from poor performance in Wayland sessions.

Enabling DRM KMS is required. There may be additional information in the official documentation regarding your display manager (e.g. GDM).

Kwin Wayland debug console

If you use kwin, execute the following to see which windows use Xwayland or native Wayland, surfaces, input events, clipboard contents, and more.

$ qdbus6 org.kde.KWin /KWin org.kde.KWin.showDebugConsole

Detect Xwayland applications visually

To determine whether an application is running via Xwayland, you can run extramaus^AUR. Move your mouse pointer over the window of an application. If the red mouse moves, the application is running via Xwayland.

Alternatively, you can use xorg-xeyes and see if the eyes are moving, when moving the mouse pointer over an application window.

An other option is to run xwininfo (from xorg-xwininfo) in a terminal window: when hovering over an Xwayland window the mouse pointer will turn into a + sign. If you click the window it will display some information and end, but it will not do anything with native Wayland windows.You can use Ctrl+C to end it.

GUI libraries

See details on the official website.

GTK

The gtk3 and gtk4 packages have 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.

For theming issues, see GTK#Wayland backend.

Qt

To enable Wayland support in Qt 5 or 6, install the qt5-wayland or qt6-wayland package, respectively. Qt applications will then run under Wayland on a Wayland session.

While it shouldn't be necessary, to explicitly run a Qt application with the Wayland plugin [4], 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 zoom^AUR. QT_QPA_PLATFORM="wayland;xcb" allows Qt to use the xcb (X11) plugin instead if Wayland is not available.[5]

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 an SDL2 application on Wayland, set SDL_VIDEODRIVER=wayland. SDL_VIDEODRIVER="wayland,x11" allows SDL2 to use the x11 video driver instead if Wayland is not available.[6]. You may also want to install libdecor to enable window decorations (for example, on GNOME).

GLFW

The glfw package has support for Wayland, and uses the Wayland backend if the environment variable XDG_SESSION_TYPE is set to wayland and the application developer has not set a specific desired backend.

See the source code for more information.

GLEW

The glew-wayland^AUR package currently still does not work with a lot of GLEW-based applications, so the only option is to use glew with Xwayland. See FS#62713.

EFL

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

winit

Winit is a window handling library in Rust. It will default to the Wayland backend, but it is possible to override it to Xwayland by modifying environment variables:

Prior to version 0.29.2, set WINIT_UNIX_BACKEND=x11
For version 0.29.2 and higher, unset WAYLAND_DISPLAY, which forces a fallback to X using the DISPLAY variable. [7]

Electron

Wayland support can be activated either using per-application command line flags or more globally using a configuration file.

To determine which electron version the application uses, see [8].

Note: In Plasma, some Electron applications can use the wrong icon (default Wayland one) for the window, while using the correct icon for the taskbar. To fix that, you can create a special application/window rule, forcing the desktop file name on such applications.

Environment variable

Applications using Electron 28 and higher can use the environment variable ELECTRON_OZONE_PLATFORM_HINT set to auto or wayland.

This takes lower priority than the command line flags.

Command line flags

Unlike on Chromium which Electron is based on, Electron applications do not enable WebRTC screen capture over PipeWire by default. Using --enable-features=WebRTCPipeWireCapturer is therefore recommended to avoid screen capture problems on Wayland. The capture is based on xdg-desktop-portal.

To use electron-based applications natively under Wayland when using the environment variable is not desirable or feasible, --ozone-platform-hint=auto can be added on Electron 20+.

A case of missing top bars can be solved by using: --enable-features=WaylandWindowDecorations. This will typically be necessary under GNOME (supported since electron17).

You can set these flags more permanently by means of modifying the .desktop file of an application and adding the flags to the end of the Exec= line, or more cleanly by using the below-described configuration files.

Note: Some packages do not forward flags to Electron, and thus will need the application developer to implement a solution.

Configuration file

Electron packages read ~/.config/electronXX-flags.conf files, where XX is Electron version, or fallback to shared ~/.config/electron-flags.conf, if the versioned file is not present.

Put the previously mentioned flags one per line:

~/.config/electron-flags.conf

--enable-features=WaylandWindowDecorations
--ozone-platform-hint=auto

Note: These configuration files only work for the Electron packages in the official repositories and packages that use them. They do not work for packages that bundle their own build of Electron such as slack-desktop^AUR. Sometimes alternatives exist such as slack-electron^AUR.

Older Electron versions

electron25-flags.conf applies only to version 25 of Electron. Older versions of Electron can be configured using their own electron<version>-flags.conf file.

Older versions may also require different flags, depending on the corresponding Chromium version. For example, the following flags work on Electron 13:

~/.config/electron13-flags.conf

--enable-features=UseOzonePlatform
--ozone-platform=wayland

Java

The open source implementation of the Java platform OpenJDK, does not yet have native support for Wayland. Until Wakefield, the project that aims to implement Wayland in OpenJDK, is available, Xwayland can be used.

See Debian:Wayland#Java Programs (supported since OpenJDK 16?):

Starting with OpenJDK 16, the JRE can dynamically load GTK3 (which has Wayland support), it appears this might be supported according to this discussion.

The _JAVA_AWT_WM_NONREPARENTING environment variable can be set to "1" to fix misbehavior where the application starts with a blank screen.

Tips and tricks

Automation

ydotool (ydotool) - Generic command-line automation tool (not limited to wayland). Enable/start the ydotool.service user unit. See ydotoold(8), ydotoold(1).
wtype (wtype) - xdotool type for wayland. See wtype(1).
keyboard - Python library that works on Windows and Linux with experimental OS X support. Also see the mouse library.
wlrctl (wlrctl^AUR) - A command line utility for miscellaneous wlroots extensions (supports the foreign-toplevel-management, virtual-keyboard, virtual-pointer)

Remap keyboard or mouse keys

See Input remap utilities.

Screencast Wayland windows with X11 applications

See Screen capture#Screencast Wayland windows with X11 applications.

Troubleshooting

Color correction

See Backlight#Color correction.

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.

Remote display

wlroots (used by sway) offers a VNC backend via wayvnc since version 0.10. RDP backend has been removed [9].
mutter has now remote desktop enabled at compile time, see [10] and gnome-remote-desktop for details.
krfb offers a VNC server for kwin. krfb-virtualmonitor can be used to set up another device as an extra monitor.
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^AUR (or waypipe-git^AUR) is a transparent proxy for Wayland applications, with a wrapper command to run over SSH
- Here is an example for launching a remote KDE kcalc under Plasma:

$ waypipe ssh example.local env QT_QPA_PLATFORM=wayland-egl QT_QPA_PLATFORMTHEME=KDE dbus-launch kcalc

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 will not 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-xwayland.

The related extensions are:

Supporting Wayland compositors:

Mutter, GNOME's compositor since release 3.28
wlroots supports relative-pointer and pointer-constraints
Kwin
- KDE#X11 shortcuts conflict on Wayland
- Keyboard shortcuts inhibit

Supporting widget toolkits:

GTK since release 3.22.18.

GTK themes not working

See https://github.com/swaywm/sway/wiki/GTK-3-settings-on-Wayland.

Avoid loading NVIDIA modules

Add __EGL_VENDOR_LIBRARY_FILENAMES=/usr/share/glvnd/egl_vendor.d/50_mesa.json as environment variable before launching a Wayland compositor like sway.

Magnifying/surface scaling

Screen magnifying is not solved yet, a pull request was merged mid-2022 providing the protocol wp-surface-scale.