swayout/README.md

swayout

swayout is a utility to configure sway outputs.

kanshi and way-displays certainly do a better job of this. I wrote this because I wanted a project to learn Rust.

Monitors and layouts are configured in a KDL file (~/.config/swayout/config.kdl).

Example config.kdl:

// This is my laptop's built-in screen.
monitor "laptop" make="Unknown" model="0x403D" serial="0x00000000" lid="LID"

// I usually have it hooked up to this monitor, which is the top one on my desk.
monitor "top" make="Dell Inc." model="DELL U2415" serial="CFV9N99T0Y0U"

// Sometimes I hook it up to these monitors, which are left and right.
// The left is in portrait.
monitor "left" make="Goldstar Company Ltd" model="LG HDR 4K" serial="0x0000B9C0"
monitor "right" make="Goldstar Company Ltd" model="LG HDR 4K" serial="0x0000B9BF"

// When I have "left" and "right" hooked up, I want this layout.
layout "two4k" automatic=#true {
    output "left" mode="3840x2160" scale="1.5" x=0 y=0 transform="270"
    output "right" mode="3840x2160" scale="1.5" x=1440 y=1120 transform="normal"
}

When you run swayout, it prints all available layout names to standard output, one per line. Printed layouts include:

• All layouts defined in config.kdl for which the monitors are currently available. E.g.: two4k.
• All monitors defined in config.kdl that are currently available. E.g.: laptop, left, right.
• All available outputs that are not matched by a configured monitor. E.g.: HDMI-2.

If a monitor has its lid property is set to the name of a directory in /proc/acpi/button/lid/, if the state file in that directory indicates that the lid is closed, the monitor will not be considered available.

If you pass a layout name (or monitor name, or output name) as a command line argument to swayout, it calls swaymsg to configure that layout. If a monitor name or output name is passed, only that monitor or output is enabled, and the output's defaults are used.

This behavior is useful in conjunction with tofi. My sway configuration has:

set $select_layout swayout | tofi | xargs swayout
bindsym $mod+Shift+m exec $select_layout

If swayout is called with the --automatic switch, the first layout with automatic=#true for which all outputs are available is enabled. If no automatic layouts are available, swayout exits with code 2.

This could be run by bindswitch lid:toggle exec swayout --automatic.

TODO

How to call when an output is connected or disconnected? Wayland events via wayland_client?