Sway window opacity change on keybindings

README.md

Sway opacity changer

• This script basically increase/decrease focused window opacity on keybind.
• It stores window opacity values in a temporary file since sway is not reliable (have no idea)

config

bindsym $mod+KP_Add exec /path/to/script/opacity.sh up
bindsym $mod+KP_Subtract exec /path/to/script/opacity.sh down

sway_opacity.sh

#!/bin/bash

direction="$1"
step=0.05
min=0.1
max=1.0
cache_file="/tmp/sway_opacity_cache"

window_id=$(swaymsg -t get_tree | jq '.. | objects | select(.focused == true) | .id')
[ -z "$window_id" ] && exit 1

current_opacity=$(grep "^$window_id " "$cache_file" 2>/dev/null | awk '{print $2}')
[ -z "$current_opacity" ] && current_opacity=1.0

if [ "$direction" == "up" ]; then
    new_opacity=$(echo "$current_opacity + $step" | bc)
else
    new_opacity=$(echo "$current_opacity - $step" | bc)
fi

new_opacity=$(echo "$new_opacity" | awk -v min="$min" -v max="$max" '
  { if ($1 < min) print min; else if ($1 > max) print max; else print $1 }')

swaymsg "[con_id=$window_id]" opacity "$new_opacity"

grep -v "^$window_id " "$cache_file" 2>/dev/null > "${cache_file}.tmp"
echo "$window_id $new_opacity" >> "${cache_file}.tmp"
mv "${cache_file}.tmp" "$cache_file"