[CMD] Backlight adjust script based on time of day

Hi,

I couldn't find a good tool for adjusting my laptop backlight automatically based on the time of day.
So I decided to give it a shot and created this CMD file. It is very rough calculus but it kinda works.
Still need to do the maths for latitude/month correction (perhaps someone has a bright idea?)

Code:

@echo off

REM ### Tweakradje 2014 
REM ### Calculating sunrise/set and adjust backlight (very rough!)
REM ### Run it with windows scheduler e.g. every hour

REM  BACKLMAX   12:00
REM              /\ 
REM             /  \     6:00
REM           -/--18:00--/-- MONTH/LAT LINE UP/DOWN (HORIZON)
REM           6:00   \  /
REM                   \/
REM  BACKLMIN        24:00

title Adjusting Backlight based on Time of day...

SET LATITUDE=52
SET MONTH=
SET HOUR=
REM BACKLDIM=10 minimal in steps of 5 upwards
REM BACKLMIN=20 minimal in steps of 5 upwards
REM BACKLMAX=100 maximal
REM DIMTIMEOUT=60 minimal in seconds
SET BACKLMAX=80
SET BACKLMIN=30
SET BACKLDIM=10
SET DIMTIMEOUT=120
SET /A BACKLDIF=%BACKLMAX%-%BACKLMIN%
SET BACKLEVEL=

REM Get the month, %DATE% like wo 15-10-2014
Set MONTH=%date:~6,2%
REM Get the Hour, %TIME% like 23:12:38,60
Set HOUR=%time:~,2%

REM For 24 hour Simulation REM next "Goto SKIP_SIMULATE" line
Goto SKIP_SIMULATE

FOR /L %%H IN (0,1,24) DO Set HOUR=%%H & Call :SKIP_SIMULATE
rem Pause
Exit /b

:SKIP_SIMULATE
REM ### BACKLEVEL goes from 0 > BACKLDIF/2 > BACKLDIF > BACKLDIF/2 > 0 by the HOUR
If %HOUR% LEQ 24 Set /A BACKLEVEL=2*%BACKLDIF%-%BACKLDIF%/12*%HOUR%
If %HOUR% LEQ 12 Set /A BACKLEVEL=%BACKLDIF%/12*%HOUR%

Set /A BACKLEVEL=%BACKLMIN%+%BACKLEVEL%
Echo Backlight Level at %HOUR%h: %BACKLEVEL%

Powercfg.exe -SetAcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEODIM %DIMTIMEOUT%
Powercfg.exe -SetDcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEODIM %DIMTIMEOUT%
Powercfg.exe -SetAcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEODIMLEVEL %BACKLDIM%
Powercfg.exe -SetDcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEODIMLEVEL %BACKLDIM%
Powercfg.exe -SetAcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEONORMALLEVEL %BACKLEVEL%
Powercfg.exe -SetDcValueIndex SCHEME_CURRENT SUB_VIDEO VIDEONORMALLEVEL %BACKLEVEL%
Powercfg.exe /s SCHEME_CURRENT

Exit /b

Just a thought.

Time of day or night really doesn't mean much unless one is outside using their computer.

The lighting in a room or building that the laptop is being used in would be my concern.

Changing the backlight with time might not match the lighting conditions where the computer is being used.