NAME
radharc - Adjust display colour temperature after the Sun
SYNOPSIS
radharc [-M method] [-S site] [-c crtc] ... [-R rule] [-p priority] [-f fade-in]
[-F fade-out] [-h [high-temp][@high-elev]] [-l [low-temp][@low-elev]]
[-W options] ... (-L latitude:longitude | -t temperature [-d] | -x)
DESCRIPTION
radharc adjusts the colour temperature of your monitor according
the the elevation of the Sun. This is intended to reduce eye strain
and reduce deplayed sleep phase syndrome.
radharc is inspired by redshift(1) but uses libcoopgamma(7) to allow it
to be used alongside other programs that also modify the monitors
colour output, as long as the also use libcoopgamma(7).
OPTIONS
The following options are supported:
-c crtc
Apply the filter to the CRTC with the monitor whose EDID is crtc.
By default, the filter is applied to all monitors.
If crtc is '?', all available CRTC's are listed.
-d
Keep the process alive and remove the filter on death.
-f fade-in
Set effect fade-in time (gradual application when the program
starts). The value is interpreted a real number of seconds.
-F fade-out
Set effect fade-out time (gradual restoration when the program
stops). The value is interpreted a real number of seconds.
-h [high-temp][@high-evel]
Selects that the colour temperature shall be high-temp Kelvins
when the Sun's elevation is high-evel degrees or higher above
the horizon.
This option only has effect when combined with the -L option.
-l [low-temp][@low-evel]
Selects that the colour temperature shall be low-temp Kelvins
when the Sun's elevation is low-evel degrees or lower above
the horizon.
This option only has effect when combined with the -L option.
-L latitude:longitude
Selects the location the Sun's elevation shall be calculated
for. The program will run until it is manually terminated and
continually readjust the colour temperature according the
the Sun's elevation. The latitude and longitude shall be
specified in decimal format. Positive numbers shall be used
GPS coordinates north of the equator and GPS coordinates
east of the prime meridian. Negative number shall be used
for GPS coordinates south of the equator and GPS coordinates
west of the prime meridian.
-M method
Adjustment method name or number. Recognised names include:
dummy Dummy method
randr X RAndR
vidmode X VidMode
drm Linux DRM
gdi Windows GDI
quartz Quartz Core Graphics
The adjustment methods are supported via libgamma(7). Only methods
that were enabled when libgamma was compiled will be supported.
If method is '?', all available adjustment methods are printed.
-p priority
Set the priority of the filter. Filters with higher priority
are applied before filters with lower priority. The value must
be a signed 64-bit integer (between -9223372036854775807 and
9223372036854775807). radharc's default priority is
-2305843009213693952.
If priority is '?', the utility's default priority is printed.
-R rule
Set the rule of the filter to rule. This is the last part of
the filter's identifier (class). The default rule is standard.
-S site
Select the site to which to connect. For example ':0', for local
display 0 when using X.
-t temperature
Colour temperature, in Kelvins, to apply.
If temperature is '?' or 'get', the utility will print the
currently applied temperature.
-W options
Comma-separated list of implementation-specific options.
Supported options are:
linear=value
If value is 'yes', the effect will be surrounded
by an effect equivalent to that of cg-linear(1),
the two effects will be applied as one.
If value is 'no', the above will not be done.
socket=name
Select name (abstract address) of the socket created
for IPC functionality.
if name is '-', the standard input will be used, and
must be a bound unix(7) datagram socket.
If no specified, and no-socket has not been
specified, a default string will be used, being
defined by the pattern
"/proc/%u/%s", <PID>, <class>
Any comma (,) will be interpeted as part of name.
no-socket
Do not create a socket for IPC functionality.
-x
Remove the currently applied filter.
OPERANDS
No operands are supported.
SIGNALS
The following signals have non-default meaning:
SIGINT
Gradually fade out the effect and terminate the process.
If the fade out time is 0 (default) or if the signal is sent
twice, the effect is removed immediately.
SIGHUP
Terminate the process after any current fade in or fade out
action, but leaf the effect in place.
SIGUSR1
Gradually fade out the effect but do not terminate the process.
If the fade out time is 0 (default) or if the signal is sent
twice, the effect is removed immediately.
SIGUSR2
Gradually fade the effect back in (from SIGUSR1).
If the fade in time is 0 (default) or if the signal is sent
twice, the effect is restored immediately.
If sent during the initial fade in, the fade in is cancelled
and the full effect is immediately applied.
SEE ALSO
radharc-ipc(1), coopgammad(1), cg-tools(7), redshift(1), blueshift(1)