Add backlight script

.local/bin/backlight

@@ -0,0 +1,43 @@
+#!/bin/bash
+set -e
+
+path="/sys/class/backlight/intel_backlight"
+
+current_abs=$(cat "$path/actual_brightness")
+max_abs=$(cat "$path/max_brightness")
+
+percent=$(( max_abs / 100 ))
+current=$(( current_abs / percent ))
+new="$current"
+
+change=$2
+
+if [ "$1" = "-get" ]
+then
+    echo "$current"
+    exit 0
+fi
+
+if [ "$1" = "-inc" ]
+then
+    new=$(( current + change ))
+fi
+if [ "$1" = "-dec" ]
+then
+    new=$(( current - change ))
+fi
+if [ "$1" = "-set" ]
+then
+    new=$2
+fi
+
+if [ "$new" -lt 10 ]
+then
+    new=10
+fi
+if [ "$new" -gt 100 ]
+then
+    new=100
+fi
+
+echo "$(( new * percent ))" | tee "$path/brightness"