NAME
radharc - Reduce eye strain and improve sleep.
PRONUNCIATION
ɹˈaɪɐrk (depending on dialect)
SYNOPSIS
radharc [OPTIONS]...
The -l option is mandatory.
OPTIONS
-l LATITUDE:LONGITUDE
Tell radharc where you are. This is mandatory.
The values are measured in degrees and in the
GPS (you probably do not have too care about that,
the differences between the systems should not
be significant another), and must be in decimal.
Reminder for Americans (particularly US Americans),
you are an the western hemisphere, not the eastern,
thus your latitude is negative. If you experience
weird colour temperatures, 100 % of the times it is
because you forgot the minus sign. But no need to
feel stupid, it is a really common mistake.
-t DAY:NIGHT
Select colour temperature to use during full daytime
and full night. This should be a integer. Do not
include the unit (the 'K').
-t TEMPERATURE
Select temperature to use. The program will exit
when it is done setting the temperature. The
natural colour temperature is 6500 K ('-t 6500').
-t +DELTA
Increase the colour temperature by DELTA Kelvin.
-t -DELTA
Decrease the colour temperature by DELTA Kelvin.
-T TEMPERATURE
Temperature that shall be used when the program
is disabled (via SIGUSR1).
-p Print the current colour temperature.
-n Set the temperature immediately, do not transition.
-N Do not transision when exiting, reset and exit
immediately on exit.
-o Set the colour immediately, and exit.
-x Ignore the current calibrations on the monitors.
-s SECONDS
The start and exit transitions shall take SECONDS
seconds. This may be a floating point number.
-i
Apply negative image filter. Radharc will detect
which monitors have this one when it starts.
-h PATHNAME
Use a hook script for events.
-b
Broadcast events with bus.
-e EDID
Select monitor to use by its EDID.
-m NUM
Select monitor to use by its global index.
-m SCREEN:NUM
Select monitor to use by its index without
a screen or graphic card. The later is for when
not inside a graphics environment.
SIGNALS
SIGHUP
Perform an online update to a newer version.
SIGUSR1
Enable or disable radharc.
SIGUSR2
Toggle negative image filter. Enable on all
monitors if it is enable on some but not all.
SIGRTMIN+N
Toggle negative image on monitor N, if monitors
have been selected manually, it will be in the
order they where selected.
NOTES
I suggest using a local script named radharc that
sets all options for you.
KNOWN ISSUES
In X.org, the gamma ramps do not apply to hardware cursors,
because the developers thinks it is the graphics drivers
that shall fix this, and they are not accepting patches for
this. You can use xorg-server-hwcursor-gamma, however, that
patched version does not apply apply the gamma ramps until
the cursor changes image. You can also use sortware cursors
if this really bothers you.
SEE ALSO
redshift(1), blueshift(1), redshift-adjust(1), nightshift(1)
