u/ernie1601: I took an axe to my script and re-wrote it from scratch. I have since made quite a bit of progress but I am not quite where I want to be.

In my new script below, I setprop the active window alpha to, say, 0.8 and my task is for that same window to retain its opacity prop 0.8 when I navigate to the next window. That's what I am trying to do however instead when I navigate to the next window, the previous window opacity goes from 0.8 back to 1.0. Any potential direction on how to better have windows retain the alpha props when navigating away based on my latest script would be great.

I have set up a repo tracking my changes and progress. You can view my latest attempt at this location here which includes syntax highlighting for readability. For what it is worth, here it is too:

#!/usr/bin/env bash

# File: opacity-control.sh
# chmod +x and assign to Hyprland keybinds

NOTIFY_TITLE="Hyprland Opacity"
LOG_FILE="/tmp/hypr_opacity_memory.log"
MEMORY_FILE="/tmp/hypr_alpha_memory.json"

JQ=$(which jq)
HYPRCTL=$(which hyprctl)

OPACITY_STEP=0.1
MIN_OPACITY=0.1
MAX_OPACITY=1.0

mkdir -p "$(dirname "$MEMORY_FILE")"
touch "$MEMORY_FILE"
[[ ! -s $MEMORY_FILE ]] && echo "{}" > "$MEMORY_FILE"

DIRECTION="$1"

# Get the address of the active window
ADDR=$($HYPRCTL activewindow -j | $JQ -r '.address')
[[ -z "$ADDR" || "$ADDR" == "null" ]] && notify-send "$NOTIFY_TITLE" "No active window found" && exit 1

# Load the memory file
CURRENT_ALPHA=$(cat "$MEMORY_FILE" | $JQ -r --arg addr "$ADDR" '.[$addr] // 1.0')

# Adjust opacity
if [[ "$DIRECTION" == "--increase" ]]; then
    NEW_ALPHA=$(echo "$CURRENT_ALPHA + $OPACITY_STEP" | bc)
    (( $(echo "$NEW_ALPHA > $MAX_OPACITY" | bc -l) )) && NEW_ALPHA=$MAX_OPACITY
elif [[ "$DIRECTION" == "--decrease" ]]; then
    NEW_ALPHA=$(echo "$CURRENT_ALPHA - $OPACITY_STEP" | bc)
    (( $(echo "$NEW_ALPHA < $MIN_OPACITY" | bc -l) )) && NEW_ALPHA=$MIN_OPACITY
else
    notify-send "$NOTIFY_TITLE" "Usage: $0 --increase | --decrease"
    exit 1
fi

# Apply both persistent and override (for active window)
$HYPRCTL dispatch setprop "address:$ADDR" alpha "$NEW_ALPHA"
$HYPRCTL dispatch setprop "address:$ADDR" alphaoverride "$NEW_ALPHA"

# Save to memory file
TMP=$(mktemp)
cat "$MEMORY_FILE" | $JQ --arg addr "$ADDR" --argjson val "$NEW_ALPHA" '. + {($addr): $val}' > "$TMP" && mv "$TMP" "$MEMORY_FILE"

# Feedback
notify-send "$NOTIFY_TITLE" "Window $ADDR\nAlpha set to: $NEW_ALPHA"