script to change brightness

awesome/rc.lua

@@ -278,7 +278,10 @@ globalkeys = awful.util.table.join(
     -- Menubar
     awful.key({ modkey }, "p", function() menubar.show() end),
     -- locking
-    awful.key({ modkey, "Control" }, "l", function () awful.util.spawn("xscreensaver-command -lock") end)
+    awful.key({ modkey, "Control" }, "l", function () awful.util.spawn("xscreensaver-command -lock") end),
+    -- brightness adjustment
+    awful.key({ }, "XF86MonBrightnessDown", function() awful.util.spawn("/home/yorick/dotfiles/bin/brightne.sh down") end),
+    awful.key({ }, "XF86MonBrightnessUp", function() awful.util.spawn("/home/yorick/dotfiles/bin/brightne.sh up") end)
 )
 
 clientkeys = awful.util.table.join(

bin/brightne.sh

@@ -0,0 +1,102 @@
+#!/bin/bash
+# brightne.sh
+
+# changes my backlight brightness, for use with nvidiabl
+# possibly the ugliest bash script ever
+
+# Requires /sys/class/backlight/nvidia_backlight/
+
+E_NOARGS=75
+
+backlight_path=/sys/class/backlight/nvidia_backlight
+
+usage() {
+  echo "Usage: brightne.sh [set|fix|up|down] arg between 0 and 1024"
+}
+
+get_raw_maximum() {
+	return `cat $backlight_path/max_brightness`
+}
+
+get_raw_current() {
+	return `cat $backlight_path/brightness`
+}
+
+set_raw() {
+	echo $1 > $backlight_path/brightness
+}
+
+# from 0-1024 to 0-max
+scale_to_bl() {
+	get_raw_maximum
+	max=$?
+	echo "$max * $1 / 1024" | bc
+}
+
+# from 0-max to 0-1024
+scale_from_bl() {
+	get_raw_maximum
+	max=$?
+	echo "1024 * $1 / $max" | bc
+}
+
+off() {
+	set_raw 0;
+}
+
+max() {
+	get_raw_maximum
+	raw_current=$?
+	set_raw $raw_current
+}
+
+set_bl() {
+	set_raw $(scale_to_bl $1)
+}
+
+get() {
+	get_raw_current
+	echo $(scale_from_bl $?)
+}
+
+fix() {
+	get_raw_current
+	set_raw $?
+}
+
+up() {
+	local addvalue=$1
+	if [ -z $1 ]
+		then
+		addvalue=10
+	fi
+	set_bl $(echo "$(get) + $addvalue" | bc)
+}
+
+down() {
+	local addvalue=$1
+	if [ -z $1 ]
+		then
+		addvalue=10
+	fi
+	set_bl $(echo "$(get) - $addvalue" | bc)
+}
+
+if [ -z "$1" ]
+then
+  usage
+  exit $E_NOARGS
+fi
+
+case $1 in
+	"up"    ) up $2;;
+	"set"    ) set_bl $2;;
+	"down"    ) down $2;;
+	"fix"    ) fix;;
+	"get"    ) get;;
+	"off"	) off ;;
+	"max"	) max ;;
+    *       ) usage;;
+esac
+
+exit 0