xlayoutdisplay

Detects and arranges outputs for an X display, using XRandR for detection and xrandr for arrangement.

Highest refresh rate of the output's preferred resolution are used.

Left-to-right ordering is used, unless the user specifies mirrorred outputs.

Laptop displays eDP.* are disabled when the lid is closed.

Wayland equivalent: way-displays.

Usage

Arranges outputs in a left to right manner, using highest resolution and refresh.
DPI is calculated based on the first or primary output's EDID information and rounded to the nearest 12.
Laptop outputs are turned off when the lid is closed.

e.g.  xlayoutdisplay -p DP-4 -o HDMI-0 -o DP-4

CLI:
  -h [ --help ]          print this help text and exit
  -i [ --info ]          print information about current outputs and exit
  -n [ --noop ]          perform a trial run and exit
  -v [ --version ]       print version string

CLI, $XDG_CONFIG_HOME/.xlayoutdisplay, $HOME/.xlayoutdisplay and /etc/xlayoutdisplay:
  -d [ --dpi ] arg       DPI override
  -r [ --rate ] arg      Refresh rate override
  -m [ --mirror ]        mirror outputs using the lowest common resolution
  -o [ --order ] arg     order of outputs, repeat as needed
  -p [ --primary ] arg   primary output
  -q [ --quiet ]         suppress feedback
  -w [ --wait ] arg      wait seconds before running

Installation

Package Manager:

Build From Source

git clone https://github.com/alex-courtis/xlayoutdisplay.git
cd xlayoutdisplay
make
sudo make install

Configuration File

$XDG_CONFIG_HOME/.xlayoutdisplay then $HOME/.xlayoutdisplay then /etc/xlayoutdisplay may be used to provide defaults, which will be overwritten by CLI options.

See xlayoutdisplay

Automatically detect new display

To automatically run xlayoutdisplay whenever a new display is plugged in or unplugged, udev can be used.

A sample rule can be found at 99-xlayoutdisplay.rules.
Simply update the value of ENV{HOME}, and copy the customized file to /etc/udev/rules.d/. pidof from procps-ng is required.

The wait time is necessary to allow Xorg time to enumerate new monitors. 5 seconds is a conservative value; experiment with smaller values for better response time.

Additional informations can be found at the udev Arch Wiki article.

Sample Output

DP-4 is the only ouput, then HDMI-0 is plugged in.

xlayoutdisplay -p DP-4 -o HDMI-0 -o DP-4

HDMI-0 is enabled to the left of DP-4, however DP-4 is still the primary output that determines DPI.

DVI-D-0 disconnected
HDMI-0 connected 0cm/0cm
 + 1920x1080 50Hz
   2880x576 50Hz
   2880x576 50Hz
   2880x480 60Hz
   2880x480 60Hz
   1920x1080 60Hz
   1920x1080 60Hz
   1920x1080 24Hz
   1920x1080 60Hz
  !1920x1080 60Hz
   1920x1080 50Hz
   1440x576 50Hz
   1440x480 60Hz
   1280x720 60Hz
   1280x720 50Hz
   720x576 50Hz
   720x480 60Hz
   640x480 60Hz
DP-0 disconnected
DP-1 disconnected
DP-2 disconnected
DP-3 disconnected
DP-4 active 60cm/34cm 2560x1440+0+0 165Hz
 + 2560x1440 60Hz
* !2560x1440 165Hz
   2560x1440 144Hz
   2560x1440 120Hz
   2560x1440 100Hz
   2560x1440 85Hz
   2560x1440 24Hz
   1024x768 60Hz
   800x600 60Hz
   640x480 60Hz
*current +preferred !optimal

laptop lid open or not present

calculated DPI 108 for output DP-4

xrandr \
 --dpi 108 \
 --output HDMI-0 --mode 1920x1080 --rate 60 --pos 0x0 \
 --output DP-4 --mode 2560x1440 --rate 165 --pos 1920x0 --primary \
 --output DVI-D-0 --off \
 --output DP-0 --off \
 --output DP-1 --off \
 --output DP-2 --off \
 --output DP-3 --off

echo "Xft.dpi: 108" | xrdb -merge

End state:

/--------------\/----------------------\
|              ||                      |
|    HDMI-0    ||                      |
|              ||        DP-4          |
|  1920x1080   ||                      |
|              ||     2560x1440        |
\--------------/|                      |
                |                      |
                |                      |
                \----------------------/

Problems

Freezing When Using NVIDIA Closed Source Drivers

xlayoutdisplay may sometimes freeze the display, when applying a (full) composition pipeline to the whole X server.

This may be avoided by running xlayoutdisplay first. You'll need to remove this bit of configuration from your Xorg conf and explicitly invoke via nvidia-settings. e.g.

From /etc/X11/xorg.conf.d/20-nvidia.conf:

Section "Screen"
    Identifier     "nvidiaSpecific"
    # Option         "metamodes" "nvidia-auto-select +0+0 {ForceFullCompositionPipeline=On, AllowGSYNCCompatible=On}"
EndSection

To .xinitrc:

xlayoutdisplay
nvidia-settings --assign CurrentMetaMode="nvidia-auto-select +0+0 {ForceFullCompositionPipeline=On, AllowGSYNCCompatible=On}"

Developing

Build

git clone https://github.com/alex-courtis/xlayoutdisplay.git
cd xlayoutdisplay
make

Build using Docker

Prepare build directory

mkdir -p build

Use one of:

Ubuntu

docker run --rm -it -v $(pwd)/build:/src --name ubuntu ubuntu:22.04 bash
apt-get update
apt-get install -y build-essential libxrandr-dev libxcursor-dev git-core pkg-config libgtest-dev libgmock-dev

OR Arch

docker run --rm -it -v $(pwd)/build:/src --name archlinux archlinux:base bash
pacman -Sy git gcc make pkgconfig libxcursor xorg-xrandr gtest gmock

Being inside the container run

cd /src
git clone --depth 1 https://github.com/alex-courtis/xlayoutdisplay .
make
exit

You may find compiled binary inside build directory

ls -la build/xlayoutdisplay

Test

Install Google Test and Google Mock.

make gtest

Contributing

PRs very welcome: fork this repo and submit a PR.

Bugs / Features

Please raise an issue.

Note again that PRs are very welcome ;)

alex-courtis / xlayoutdisplay