Sway / Switch refresh rate (MAX_REFRESH_RATE) without vrr with half this value + vrr

switch_refresh.sh

#!/bin/bash

function usage() {
    echo "Usage: $0 <mode>"
    echo "Modes:"
    echo -e "\t- switch: Switch between max refresh rate with VRR disabled to half the refresh rate and VRR enabled"
    echo -e "\t- read: Read the current refresh rate"
}

# check min args
if [ "$#" -ne 1 ]; then
    usage
    exit 1
fi
MODE=$1

# check mode values
if [ "${MODE}" != "switch" ] && [ "${MODE}" != "read" ]; then
    echo "Invalid mode: ${MODE}"
    echo ""
    usage
    exit 1
fi

OUT=$(swaymsg -t get_outputs | jq -r '.[] | select(.focused == true) | "\(.name) \(.current_mode.width) \(.current_mode.height) \(.current_mode.refresh) \(.adaptive_sync_status)"')
IFS=' ' read -r OUTPUT_NAME OUTPUT_WIDTH OUTPUT_HEIGHT OUTPUT_REFRESH VRR <<< "$OUT"

# in read mode
OUTPUT_REFRESH=$((OUTPUT_REFRESH / 1000))

if [ "${MODE}" == "read" ]; then
    # check if VRR is enabled
    if [ "${VRR}" == "enabled" ]; then
        echo "${OUTPUT_REFRESH}Hz vrr"
    else
        echo "${OUTPUT_REFRESH}Hz"
    fi
    exit 0
fi

# in switch mode

REFRESH_RATES=($(swaymsg -t get_outputs | jq -r \
  --argjson w "${OUTPUT_WIDTH}" \
  --argjson h "${OUTPUT_HEIGHT}" \
  '.[] | select(.focused == true) | .modes[] 
   | select(.width == $w and .height == $h) 
   | .refresh'))

MAX_REFRESH_RATE=$(echo ${REFRESH_RATES} | sort -nr | head -n1)

closest() {
    TARGET=$((MAX_REFRESH_RATE / 2))
    local closest_val diff min_diff val
    min_diff=
    for val in "${REFRESH_RATES[@]}"; do
        diff=$(( val > TARGET ? val - TARGET : TARGET - val ))
        if [ -z "$min_diff" ] || [ "$diff" -lt "$min_diff" ]; then
            min_diff=$diff
            closest_val=$val
        fi
    done
    echo "$closest_val"
}
MIN_REFRESH_RATE=$(closest)

MAX_REFRESH_RATE=$((MAX_REFRESH_RATE / 1000))
MIN_REFRESH_RATE=$((MIN_REFRESH_RATE / 1000))

echo MAX_REFRESH_RATE: ${MAX_REFRESH_RATE}Hz
echo MIN_REFRESH_RATE: ${MIN_REFRESH_RATE}Hz

# based on refresh rate (wxh@<refresh>Hz)
if [[ "${OUTPUT_REFRESH}" == "${MAX_REFRESH_RATE}" ]]; then
    # set to MIN_REFRESH_RATE (VRR enabled)
    swaymsg output "${OUTPUT_NAME}" mode ${OUTPUT_WIDTH}x${OUTPUT_HEIGHT}@${MIN_REFRESH_RATE}Hz adaptive_sync on
else
    # set to MAX_REFRESH_RATE (VRR disabled)
    swaymsg output "${OUTPUT_NAME}" mode ${OUTPUT_WIDTH}x${OUTPUT_HEIGHT}@${MAX_REFRESH_RATE}Hz adaptive_sync off
fi