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@caub
Last active March 15, 2018 09:50
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#!/bin/bash
regexp='^[-+]?[0-9]*(\.[0-9]*)?$'
validateNumber() {
if [[ $1 == *[0-9]* && $1 =~ $regexp ]]; then
echo "$1"
else
printf >&2 '%s is not a valid number\n' "$1"
fi
}
# compare 2 numbers, similar and faster than if (( $(bc <<<"$1 < $2") ))
isGreater() {
local v1
local v2
LC_NUMERIC=C printf -v v1 '%f' "$1"
LC_NUMERIC=C printf -v v2 '%f' "$2"
local i1="${v1%.*}"
local i2="${v2%.*}"
local d1="${v1#*.}"
local d2="${v2#*.}"
d1="${d1:0:2}"
d2="${d2:0:2}"
if [[ "$d1" == 0* ]]; then d1="${d1:1}"; fi # deal with octals
if [[ "$d2" == 0* ]]; then d2="${d2:1}"; fi
# now compare integer parts or decimal parts if needed
return $(( i1 == i2 ? d1 <= d2 : i1 <= i2 ))
}
# add 2 numbers (2 decimals max, similar and faster than echo "scale=2; $1 + $2" | bc)
addNum() {
local v1
local v2
LC_NUMERIC=C printf -v v1 '%f' "$1"
LC_NUMERIC=C printf -v v2 '%f' "$2"
local i1="${v1%.*}"
local i2="${v2%.*}"
local d1="${v1#*.}"
local d2="${v2#*.}"
d1="${d1:0:2}"
d2="${d2:0:2}"
if [[ "$d1" == 0* ]]; then d1="${d1:1}"; fi # deal with octals
if [[ "$d2" == 0* ]]; then d2="${d2:1}"; fi
if [[ "$i1" == -* ]]; then d1="-$d1"; fi
if [[ "$i2" == -* ]]; then d2="-$d2"; fi
local d3=$(( d1 + d2 ))
local i3=$(( i1 + i2 ))
if (( d3 >= 100 )); then
d3=$(( d3 - 100 ))
i3=$(( i3 + 1 ))
elif (( d3 <= -100 )); then
d3=$(( -d3 - 100 ))
i3=$(( i3 - 1 ))
elif (( d3 < 0 && i3 > 0 )); then
d3=$(( d3 + 100 ))
i3=$(( i3 - 1 ))
elif (( d3 > 0 && i3 < 0 )); then
d3=$(( d3 - 100 ))
i3=$(( i3 + 1 ))
fi
if (( d3 < 0 && i3 >= 0 )); then
i3="-${i3#-}"
fi
local u="00${d3#-}"
d3="${u:0-2}"
echo "$i3.$d3"
}
getCurrent() {
local bl=$(xbacklight -get)
if [[ "$bl" == 0.* || "$bl" == 1.00* ]]; then
xrandr --verbose | awk '/Brightness/ { print $2; exit }'
else
echo "$bl"
fi
}
if [ ! "$1" ]; then
xrandr --verbose | grep -E '(Brightness|Gamma|Backlight)'
exit
fi
# use this to decr or incr brightness: light +/- value?
case "$1" in
[+-])
c=$(getCurrent)
auto=0
step="$1$2"
if [[ ! "$2" ]]; then
auto=1
step="${1}1"
if [[ "$c" == 0.* || ("$1" == '-' && "$c" == 1.*) ]]; then
step="$1.05"
fi
fi
val=$(addNum "$c" "$step");;
*)
val=$(validateNumber "$1");;
esac
if [[ ! $val ]]; then
echo "nope:" "$@"
exit
fi
if [[ $val == 0.* || $val == .* ]]; then
# xbacklight -set 1
tee /sys/class/backlight/intel_backlight/brightness <<< 30
if isGreater "$val" 0.66; then
xrandr --output eDP1 --brightness "$val" --gamma 1.0:0.8:0.65
else
xrandr --output eDP1 --brightness "$val" --gamma 1.0:0.7:0.45
fi
else
xbacklight -set "$val"
if (( val < 3 )); then
xrandr --output eDP1 --brightness 1 --gamma 1.0:0.9:0.82
elif (( val < 10 )); then
xrandr --output eDP1 --brightness 1 --gamma 1.0:0.96:0.9
else
xrandr --output eDP1 --brightness 1 --gamma 1.0:1.0:0.95
fi
fi
@caub
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caub commented Mar 12, 2018

this file above is in my home

I've added a sudoers entry to run the line 102 caub@inspiron:~$ sudo visudo -f /etc/sudoers.d/light

caub ALL=(root) NOPASSWD:/home/caub/.light

now sudo ~/.light .7 works fine, you can add a bash_alias aslias li='sudo ~/.light'

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