Wayland

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Wayland is a protocol for a compositor to talk to its clients, as well as a library implementing this protocol. All major GNU/Linux desktop systems like GNOME, KDE do support Wayland, and there is also a reference implementation for a compositor called "Weston". XWayland implements a compatibility layer to seamlessly run legacy X11 applications on Wayland.

1 Requirements

Wayland only works on systems using KMS. As Wayland is only a library, it is useless on its own: to replace the X Server you need a compositor such as #Weston.

2 Weston

Weston is the reference implementation of a Wayland compositor.

2.1 Installation

Install the sddm (or gdm) and weston packages.

2.2 Usage

Keyboard Shortcuts (super = windows key - can be changed, see weston.ini) Ctrl-b
Cmd Action
Ctrl + Alt + Backspace Quit Weston
Super + Scroll (or PageUp/PageDown) Zoom in/out of desktop
Super + Tab Switch windows
Super + LMB Move Window
Super + MMB Rotate Window !
Super + RMB Resize Window
Super + Alt + Scroll Change window opacity
Super + K Force Kill Active Window
Super + KeyUp/KeyDown Switch Prev/Next Workspace
Super + Shift + KeyUp/KeyDown Grab Current Window and Switch Workspace
Super + Fn Switch to Workspace n
Super + S Take a screenshot
Super + R Record a screencast.

Now that Wayland and its requirements are installed you should be ready to test it out.

It is possible to run Weston inside a running X session:

$ weston

Alternatively, to try to launch Weston natively, switch to a terminal and run:

$ weston-launch

Then at a TTY within Weston, you can run the demos. To launch a terminal emulator:

$ weston-terminal

To move flowers around the screen:

$ weston-flower

To display images:

$ weston-image image1.jpg image2.jpg...

2.3 Configuration

Example configuration file for keyboard layout, module selection and UI modifications. See man weston.ini for full details. The Weston outputs differ slightly from xorg.conf's Monitors:

$ ls /sys/class/drm
card0
card0-VGA-1
card1
card1-DVI-I-1
card1-HDMI-A-1
card1-VGA-2

card0 is the unused built-in video adapter. The add-on adapter card1 is cabled to one HDMI and one DVI monitor, so the output names are HDMI-A-1 and DVI-I-1.

~/.config/weston.ini
[core]
# xwayland support
modules=xwayland.so
[libinput]
enable_tap=true
[shell]
background-image=/usr/share/backgrounds/gnome/Aqua.jpg
background-color=0xff002244
panel-color=0x90ff0000
locking=true
animation=zoom
close-animation=fade
focus-animation=dim-layer
#binding-modifier=ctrl
#num-workspaces=6
### for cursor themes install xcursor-themes pkg from Extra. ###
#cursor-theme=whiteglass
#cursor-size=24

### tablet options ###
#lockscreen-icon=/usr/share/icons/gnome/256x256/actions/lock.png
#lockscreen=/usr/share/backgrounds/gnome/Garden.jpg
#homescreen=/usr/share/backgrounds/gnome/Blinds.jpg
#animation=fade

###  for Laptop displays  ###
#[output]
#name=LVDS1
#mode=1680x1050
#transform=90

#[output]
#name=VGA1
# The following sets the mode with a modeline, you can get modelines for your preffered resolutions using the cvt utility
#mode=173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
#transform=flipped

#[output]
#name=X1
#mode=1024x768
#transform=flipped-270

[input-method]
#path=/usr/lib/weston/weston-keyboard

[keyboard]
keymap_rules=evdev
#keymap_layout=gb,de
#keymap_options=caps:ctrl_modifier,shift:both_capslock_cancel
### keymap_options from /usr/share/X11/xkb/rules/base.lst ###
numlock-on=true

[terminal]
#font=DroidSansMono
#font-size=14

[launcher]
icon=/usr/share/icons/gnome/24x24/apps/utilities-terminal.png
path=/usr/bin/weston-terminal

[launcher]
icon=/usr/share/icons/gnome/24x24/apps/utilities-terminal.png
path=/usr/bin/gnome-terminal

[launcher]
icon=/usr/share/icons/hicolor/24x24/apps/firefox.png
path=/usr/bin/firefox

[launcher]
icon=/usr/share/weston/icon_flower.png
path=/usr/bin/weston-flower

[screensaver]
# Uncomment path to disable screensaver
path=/usr/libexec/weston-screensaver
duration=600

Minimal weston.ini :

~/.config/weston.ini
[core]
modules=xwayland.so

[keyboard]
keymap_layout=gb

[output]
name=LVDS1
mode=1680x1050
transform=90

[launcher]
icon=/usr/share/icons/gnome/24x24/apps/utilities-terminal.png
path=/usr/bin/weston-terminal

[launcher]
icon=/usr/share/icons/hicolor/24x24/apps/firefox.png
path=/usr/bin/firefox

2.3.1 XWayland

Install the xorg-server-xwayland package. When you want to run an X application from within Weston, it spins up Xwayland to service the request. The following configuration is shown above:

~/.config/weston.ini
[core]
modules=xwayland.so

2.3.2 Screencast recording

Weston has build-in screencast recording which can be started and stopped by pressing the Super+r key combination. Screencasts are saved to the file capture.wcap in the current working directory of Weston.

The WCAP format is a lossless video format specific to Weston, which only records the difference in frames. To be able to play the recorded screencast, the WCAP file will need to be converted to a format which a media player can understand. First, convert the capture to the YUV pixel format:

$ wcap-decode capture.wcap --yuv4mpeg2 > capture.y4m

The YUV file can then be transcoded to other formats using FFmpeg.

2.3.3 High DPI displays

For Retina or HiDPI displays, use:

~/.config/weston.ini
[output]
name=...
scale=2

2.3.4 Shell font

Weston uses the default sans-serif font for window title bars, clocks, etc. See Font configuration#Replace or set default fonts for instructions on how to change this font.

3 GNOME

3.1 Install and test

If you run GNOME, install XWayland with the xorg-server-xwayland package, then run it:

$ dbus-run-session -- gnome-shell --display-server --wayland

To test, install the weston package and run one of its applications, for example:

$ weston-stacking

This is still experimental (state 2016-11-18) and not everything will run as expected. Known issues:

  • When launching without GDM, gnome-session needs to be started manual, no shutdown/restart buttons work (gnome issue 774774)
  • Starting X11 on tty1, wayland on tty2: windows of gnome applications end up on tty2 no matter where started (gnome issue 774775)
  • Not all weston applications work, e.g. weston-terminal.
This article or section needs expansion.
Please help expand this article so the intended scope is covered in sufficient detail. (Discuss)
  • As of November 2016 there is an ongoing discussion how to implement screen recording. Currently the compositors implement at least basic functionality, so does gnome.

3.2 Autostart

To auto-start on login, only on virtual terminal 1, one can enter this into .bash_profile:

[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && dbus-run-session -- gnome-shell --display-server --wayland

More details on this way of starting are on Xinit#Autostart X at login (not using a display manager) and GNOME#Manually (resp via xinit in this case).

3.3 hints

some practical settings. for nemo prevent that the desktop is created <ref>nemo issue 1343</ref>

gsettings set org.nemo.desktop show-desktop-icons false

gparted wants to run as root, before starting it allow all local users to display applications on your desktop by typing in a command line:

 xhost +local:

4 GUI libraries

See details on the official website.

4.1 GTK+ 3

The gtk3 package from the official repositories now has the Wayland backend enabled.

GTK+ 3 gained support for multiple backends at runtime and can switch between backends in the same way Qt can with lighthouse.

When both Wayland and X backends are enabled, GTK+ will default to the X11 backend, but this can be overridden by modifying an environment variable: GDK_BACKEND=wayland.

4.2 Qt 5

The qt5 package from the repositories has the Wayland support if qt5-wayland is installed. To run a Qt 5 app with the Wayland plugin, set the QT_QPA_PLATFORM=wayland-egl environment variable.

4.3 Clutter

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

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

4.4 SDL

Experimental wayland support is now in SDL 2.0.2 and enabled by default on Parabola.

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

4.5 GLFW

Experimental wayland support is now in GLFW 3.1 and can be enabled with the -DGLFW_USE_WAYLAND=ON CMake option at compile time. You can also install the package glfw-wayland.

4.6 EFL

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

5 Window managers and desktop shells

Name Type Description
Liri Compositing See Liri.
GNOME Compositing See GNOME#Starting GNOME.
Hawaii (Unclear) See Hawaii.
sway Tiling Sway is an i3-compatible window manager for Wayland. Github
Enlightenment (Unclear) Long running minimal Window Manager-turned Wayland compositor. E19 originally had Wayland support but this was removed and now only E20+ Wayland is considered stable enough for regular use. More Info
KDE Plasma Compositing See KDE#Starting Plasma
Orbment Tiling orbment (previously loliwm) is a tiling WM for Wayland.
Velox Tiling Velox is a simple window manager based on swc. It is inspired by dwm and xmonad.
Orbital Compositing Orbital is a Wayland compositor and shell, using Qt5 and Weston. The goal of the project is to build a simple yet flexible and good looking Wayland desktop. It is not a full fledged DE but rather the analogue of a WM in the X11 world, such as Awesome or Fluxbox.
Papyros Shell (Unclear) Papyros Shell is the desktop shell for Papyros, 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.
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
Grefsen Floating Grefsen is a Qt/Wayland compositor providing a minimal desktop environment.

Some of installed wayland desktop clients might store information in /usr/share/wayland-sessions/*.desktop files about how to start them in wayland.

6 Troubleshooting

6.1 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

6.2 Applications using dbus crashes on startup

For a temporary solution, use dbus-launch to run the application. For example, to launch gnome-terminal inside a weston session, this command is sufficient.

 dbus-launch gnome-terminal

6.3 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.

7 See also

8 Acknowledgement

This wiki article is based on ArchWiki. We may have removed non-FSDG bits from it.