mango-monitors

A small GTK GUI for arranging your displays under MangoWM.

Mango configures monitors through monitorrule= lines in its config file, which is fine until you actually want to drag a screen somewhere or change a resolution without counting pixels in your head. This is a little point-and-click front end for that: drag the monitors into place, set their resolution / refresh / scale / rotation, and apply.

Features

• Drag-to-arrange canvas with edge snapping
• Per-monitor resolution, refresh rate, scale, rotation and VRR
• Enable / disable individual outputs
• Custom mode entry for resolutions the panel doesn't advertise
• Apply to change the layout live, or Save to just write it to the config
• A 15-second "keep or revert" prompt after applying, in case a mode leaves you staring at a black screen
• Hotplug aware: plug or unplug a monitor and the layout updates on its own
• "Identify" sends a notification to each screen so you know which is which

Requirements

• MangoWM (provides mango and mmsg)
• Python 3 with PyGObject, GTK 4 and libadwaita
• wlr-randr (recommended — used to read the full mode list and live geometry; without it the app falls back to wayland-info and the current mode only)

On Arch / CachyOS:

sudo pacman -S python-gobject gtk4 libadwaita wlr-randr

On Debian / Ubuntu:

sudo apt install python3-gi gir1.2-gtk-4.0 gir1.2-adw-1 wlr-randr

Install

It's a single Python script — there's nothing to compile. Either run it straight from the checkout:

./mango-monitors

or install it for your user (copies the script to ~/.local/bin and adds a desktop entry):

./install.sh

To remove it again:

./install.sh --uninstall

How it works

• Reading the current setup — wlr-randr gives the live state of each output (available modes, position, scale, transform, adaptive sync). Output names come from mmsg -O.
• Saving — the app writes a managed block of monitorrule= lines into ~/.config/mango/config.conf, fenced between two marker comments so it can rewrite just that block and leave the rest of your config alone. The first time it writes, it makes a config.conf.bak-mango-monitors backup next to it.
• Applying — it calls mmsg -d reload_config, which makes mango re-read the config and commit the new monitor geometry. Disabled outputs are switched off with mmsg -d disable_monitor,NAME and kept off across restarts with a small exec-once line in the managed block.
• Hotplug — a 2-second timer watches the output list; connecting or disconnecting a monitor updates the canvas while keeping any edits you've made to the monitors that are still attached.

The generated lines look like this:

# >>> mango-monitors (managed) — do not edit by hand >>>
monitorrule=name:^DP-1$,width:1920,height:1080,refresh:60,x:0,y:0,scale:1,rr:0,vrr:0
monitorrule=name:^eDP-1$,width:1920,height:1200,refresh:60,x:1920,y:0,scale:1,rr:0,vrr:0
# <<< mango-monitors (managed) <<<

You can edit them by hand too; the app just saves you the arithmetic. See mango's monitor documentation for the full list of monitorrule fields.

Notes

• Layouts are normalised so the top-left monitor sits at (0,0). XWayland mishandles negative output coordinates, so the app avoids them.
• The accent colours in the script are picked for a light theme. If you run a dark one, the handful of ACCENT / CANVAS_BG constants near the top are easy to change.

License

MIT. See LICENSE.