# hs.redshift

Inverts and/or lowers the color temperature of the screen(s) on a schedule, for a more pleasant experience at night

Usage:

-- make a windowfilterDisable for redshift: VLC, Photos and screensaver/login window will disable color adjustment and inversion
local wfRedshift=hs.window.filter.new({VLC={focused=true},Photos={focused=true},loginwindow={visible=true,allowRoles='*'}},'wf-redshift')
-- start redshift: 2800K + inverted from 21 to 7, very long transition duration (19->23 and 5->9)
hs.redshift.start(2800,'21:00','7:00','4h',true,wfRedshift)
-- allow manual control of inverted colors
hs.hotkey.bind(HYPER,'f1','Invert',hs.redshift.toggleInvert)

Note:

  • As of macOS 10.12.4, Apple provides "Night Shift", which implements a simple red-shift effect, as part of the OS. It seems unlikely that hs.redshift will see significant future development.

# API Overview

Variables - Configurable values

  • COLORRAMP

Functions - API calls offered directly by the extension

  • invertSubscribe
  • invertUnsubscribe
  • isInverted
  • requestInvert
  • start
  • stop
  • toggle
  • toggleInvert

# API Documentation

# Variables

# COLORRAMP

Signature hs.redshift.COLORRAMP
Type Variable
Description A table holding the gamma values for given color temperatures; each key must be a color temperature number in K (useful values are between
Notes
  • hs.inspect(hs.redshift.COLORRAMP) from the console will show you how the table is built
  • the default ramp has entries from 1000K to 10000K every 100K
Source extensions/redshift/redshift.lua line 342

# Functions

# invertSubscribe

Signature hs.redshift.invertSubscribe([id,]fn)
Type Function
Description Subscribes a callback to be notified when the color inversion status changes
Parameters
  • id - (optional) a string identifying the requester (usually the module name); if omitted, fn itself will be the identifier; this identifier must be passed to hs.redshift.invertUnsubscribe()
  • fn - a function that will be called whenever color inversion status changes; it must accept a single parameter, a string or false as per the return value of hs.redshift.isInverted()
Returns
  • None
Notes
  • You can use this to dynamically adjust the UI colors in your modules or configuration, if appropriate.
Examples None
Source extensions/redshift/redshift.lua line 107

# invertUnsubscribe

Signature hs.redshift.invertUnsubscribe(id)
Type Function
Description Unsubscribes a previously subscribed color inversion change callback
Parameters
  • id - a string identifying the requester or the callback function itself, depending on how you called hs.redshift.invertSubscribe()
Returns
  • None
Notes None
Examples None
Source extensions/redshift/redshift.lua line 128

# isInverted

Signature hs.redshift.isInverted() -> string or false
Type Function
Description Checks if the colors are currently inverted
Parameters
  • None
Returns
  • false if the colors are not currently inverted; otherwise, a string indicating the reason, one of:
  • "user" for the user override (see hs.redshift.toggleInvert())
  • "redshift-night" if hs.redshift.start() was called with invertAtNight set to true,
  • and it's currently night time
  • the ID string (usually the module name) provided to hs.redshift.requestInvert(), if another module requested color inversion
Notes None
Examples None
Source extensions/redshift/redshift.lua line 144

# requestInvert

Signature hs.redshift.requestInvert(id,v)
Type Function
Description Sets or clears a request for color inversion
Parameters
  • id - a string identifying the requester (usually the module name)
  • v - a boolean indicating whether to invert the colors (if true) or clear any previous requests (if false or nil)
Returns
  • None
Notes
  • you can use this function e.g. to automatically invert colors if the ambient light sensor reading drops below
  • a certain threshold (hs.brightness.DDCauto() can optionally do exactly that)
  • if the user's configuration doesn't explicitly start the redshift module, calling this will have no effect
Examples None
Source extensions/redshift/redshift.lua line 161

# start

Signature hs.redshift.start(colorTemp,nightStart,nightEnd[,transition[,invertAtNight[,windowfilterDisable[,dayColorTemp]]]])
Type Function
Description Sets the schedule and (re)starts the module
Parameters
  • colorTemp - a number indicating the desired color temperature (Kelvin) during the night cycle; the recommended range is between 3600K and 1400K; lower values (minimum 1000K) result in a more pronounced adjustment
  • nightStart - a string in the format "HH:MM" (24-hour clock) or number of seconds after midnight (see hs.timer.seconds()) indicating when the night cycle should start
  • nightEnd - a string in the format "HH:MM" (24-hour clock) or number of seconds after midnight (see hs.timer.seconds()) indicating when the night cycle should end
  • transition - (optional) a string or number of seconds (see hs.timer.seconds()) indicating the duration of the transition to the night color temperature and back; if omitted, defaults to 1 hour
  • invertAtNight - (optional) a boolean indicating whether the colors should be inverted (in addition to the color temperature shift) during the night; if omitted, defaults to false
  • windowfilterDisable - (optional) an hs.window.filter instance that will disable color adjustment (and color inversion) whenever any window is allowed; alternatively, you can just provide a list of application names (typically media apps and/or apps for color-sensitive work) and a windowfilter will be created for you that disables color adjustment whenever one of these apps is focused
  • dayColorTemp - (optional) a number indicating the desired color temperature (in Kelvin) during the day cycle; you can use this to maintain some degree of "redshift" during the day as well, or, if desired, you can specify a value higher than 6500K (up to 10000K) for more bluish colors, although that's not recommended; if omitted, defaults to 6500K, which disables color adjustment and restores your screens' original color profiles
Returns
  • None
Notes None
Examples None
Source extensions/redshift/redshift.lua line 273

# stop

Signature hs.redshift.stop()
Type Function
Description Stops the module and disables color adjustment and color inversion
Parameters
  • None
Returns
  • None
Notes None
Examples None
Source extensions/redshift/redshift.lua line 243

# toggle

Signature hs.redshift.toggle([v])
Type Function
Description Sets or clears the user override for color temperature adjustment.
Parameters
  • v - (optional) a boolean; if true, the override will enable color temperature adjustment on the given schedule; if false, the override will disable color temperature adjustment; if omitted or nil, it will toggle the override, i.e. clear it if it's currently enforced, or set it to the opposite of the current color temperature adjustment status otherwise.
Returns
  • None
Notes
  • This function should be bound to a hotkey, e.g.: hs.hotkey.bind('ctrl-cmd','-','Redshift',hs.redshift.toggle)
Examples None
Source extensions/redshift/redshift.lua line 218

# toggleInvert

Signature hs.redshift.toggleInvert([v])
Type Function
Description Sets or clears the user override for color inversion.
Parameters
  • v - (optional) a boolean; if true, the override will invert the colors no matter what; if false, the override will disable color inversion no matter what; if omitted or nil, it will toggle the override, i.e. clear it if it's currently enforced, or set it to the opposite of the current color inversion status otherwise.
Returns
  • None
Notes
  • This function should be bound to a hotkey, e.g.: hs.hotkey.bind('ctrl-cmd','=','Invert',hs.redshift.toggleInvert)
Examples None
Source extensions/redshift/redshift.lua line 195