esphome-docs/components/light/index.rst

Light Component
===============

.. seo::
    :description: Instructions for setting up lights and light effects in ESPHome.
    :image: folder-open.png

The ``light`` domain in ESPHome lets you create lights that will
automatically be shown in Home Assistant’s frontend and have many
features such as RGB colors, transitions, flashing and effects.

This component restores its state on reboot/reset.

.. _config-light:

Base Light Configuration
------------------------

All light configuration schemas inherit these options.

.. code-block:: yaml

    light:
      - platform: ...


Configuration variables:

- **effects** (*Optional*, list): A list of :ref:`light effects <light-effects>` to use for this light.
- **gamma_correct** (*Optional*, float): Apply a `gamma correction
  factor <https://en.wikipedia.org/wiki/Gamma_correction>`__ to the light channels.
  Defaults to ``2.8``.
- **default_transition_length** (*Optional*, :ref:`config-time`): The default transition length
  to use when no transition length is set in the light call. Defaults to ``1s``.
- **restore_mode** (*Optional*): Control how the GPIO Switch attempts to restore state on bootup.
  For restoring on ESP8266s, also see ``esp8266_restore_from_flash`` in the
  :doc:`esphome section </components/esphome>`.

    - ``RESTORE_DEFAULT_OFF`` (Default) - Attempt to restore state and default to OFF if not possible to restore.
    - ``RESTORE_DEFAULT_ON`` - Attempt to restore state and default to ON.
    - ``ALWAYS_OFF`` - Always initialize the light as OFF on bootup.
    - ``ALWAYS_ON`` - Always initialize the light as ON on bootup.

Additional Configuration variables for addressable lights:

- **color_correct** (*Optional*, list of float): Apply a color correction to each color channel.
  This defines the maximum brightness of each channel. For example ``[100%, 50%, 100%]`` would set the
  green channel to be at most at 50% brightness.
- **power_supply** (*Optional*, :ref:`config-id`): The :doc:`/components/power_supply` to connect to
  this light. When the light is turned on, the power supply will automatically be switched on too.

Advanced options:

- **internal** (*Optional*, boolean): Mark this component as internal. Internal components will
  not be exposed to the frontend (like Home Assistant). Only specifying an ``id`` without
  a ``name`` will implicitly set this to true.
- If MQTT enabled, all other options from :ref:`MQTT Component <config-mqtt-component>`.

.. _light-toggle_action:

``light.toggle`` Action
-----------------------

This action toggles a light with the given ID when executed.

.. code-block:: yaml

    on_...:
      then:
        - light.toggle:
            id: light_1
        # Shorthand:
        - light.toggle: light_1

Configuration options:

- **id** (**Required**, :ref:`config-id`): The ID of the light.
- **transition_length** (*Optional*, :ref:`config-time`, :ref:`templatable <config-templatable>`): The length of the transition
  if the light supports it.

.. note::

    This action can also be expressed in :ref:`lambdas <config-lambda>`:

    .. code-block:: cpp

        auto call = id(light_1).toggle();
        // perform action:
        call.perform();

.. _light-turn_on_action:

``light.turn_on`` Action
------------------------

This action turns a light with the given ID on when executed.

.. code-block:: yaml

    on_...:
      then:
        - light.turn_on:
            id: light_1
            brightness: 100%
            red: 100%
            green: 100%
            blue: 1.0

        # Templated
        - light.turn_on:
            id: light_1
            brightness: !lambda |-
              // output value must be in range 0 - 1.0
              return id(some_sensor).state / 100.0;

        # Shorthand
        - light.turn_on: light_1

Configuration options:

- **id** (**Required**, :ref:`config-id`): The ID of the light.
- **transition_length** (*Optional*, :ref:`config-time`, :ref:`templatable <config-templatable>`): The length of the transition
  if the light supports it.
- **brightness** (*Optional*, percentage, :ref:`templatable <config-templatable>`): The brightness of the light. Must be in range
  ``0%`` to ``100%`` or ``0.0`` to ``1.0``. Defaults to not changing brightness.
- **red** (*Optional*, percentage, :ref:`templatable <config-templatable>`): The red channel of the light. Must be in range
  ``0%`` to ``100%`` or ``0.0`` to ``1.0``. Defaults to not changing red.
- **green** (*Optional*, percentage, :ref:`templatable <config-templatable>`): The green channel of the light. Must be in range
  ``0%`` to ``100%`` or ``0.0`` to ``1.0``. Defaults to not changing green channel.
- **blue** (*Optional*, percentage, :ref:`templatable <config-templatable>`): The blue channel of the light. Must be in range
  ``0%`` to ``100%`` or ``0.0`` to ``1.0``. Defaults to not changing blue channel.
- **white** (*Optional*, percentage, :ref:`templatable <config-templatable>`): The white channel value of RGBW lights. Must be in range
  ``0%`` to ``100%`` or ``0.0`` to ``1.0``. Defaults to not changing white value.
- **flash_length** (*Optional*, :ref:`config-time`, :ref:`templatable <config-templatable>`): If set, will flash the given color
  for this period of time and then go back to the previous state.
- **effect** (*Optional*, string, :ref:`templatable <config-templatable>`): If set, will attempt to
  start an effect with the given name.

.. note::

    This action can also be expressed in :ref:`lambdas <config-lambda>`:

    .. code-block:: cpp

        auto call = id(light_1).turn_on();
        // set parameters (optional)
        call.set_transition_length(1000); // in ms
        call.set_brightness(1.0); // 1.0 is full brightness
        call.set_rgb(1.0, 1.0, 1.0); // color, 1.0 is fully lit
        call.set_effect("The Effect");
        // perform action:
        call.perform();

.. note::

    The ``red``, ``green`` and ``blue`` values only control the color of the light, not its
    brightness! If you assign ``50%`` to all RGB channels it will be interpreted as 100% on.
    Only use ``brightness`` to control the brightness of the light.

.. _light-turn_off_action:

``light.turn_off`` Action
-------------------------

This action turns a light with the given ID off when executed.

.. code-block:: yaml

    on_...:
      then:
        - light.turn_off:
            id: light_1

        # Shorthand
        - light.turn_off: light_1

Configuration options:

- **id** (**Required**, :ref:`config-id`): The ID of the light.
- **transition_length** (*Optional*, :ref:`config-time`, :ref:`templatable <config-templatable>`): The length of the transition
  if the light supports it.

.. note::

    This action can also be expressed in :ref:`lambdas <config-lambda>`:

    .. code-block:: cpp

        auto call = id(light_1).turn_off();
        // set parameters (optional)
        call.set_transition_length(1000); // in ms
        // perform action:
        call.perform();

.. _light-control_action:

``light.control`` Action
------------------------

This :ref:`Action <config-action>` is a generic call to change the state of a light - it
is essentially just a combination of the turn_on and turn_off calls.

.. code-block:: yaml

    on_...:
      then:
        - light.control:
            id: light_1
            state: on

Configuration options:

- **id** (**Required**, :ref:`config-id`): The ID of the light.
- **state** (*Optional*, :ref:`templatable <config-templatable>`, boolean): Change the ON/OFF
  state of the light.
- All other options from :ref:`light.turn_on <light-turn_on_action>`.

.. _light-dim_relative_action:

``light.dim_relative`` Action
-----------------------------

This :ref:`Action <config-action>` allows you to dim a light that supports brightness
by a relative amount.

.. code-block:: yaml

    on_...:
      then:
        # Increases the brightness by 5%
        - light.dim_relative:
            id: light_1
            relative_brightness: 5%

Configuration options:

- **id** (**Required**, :ref:`config-id`): The ID of the light.
- **relative_brightness** (**Required***, :ref:`templatable <config-templatable>`, percentage):
  The relative brightness to dim the light by.
- **transition_length** (*Optional*, :ref:`config-time`, :ref:`templatable <config-templatable>`): The length of the transition.

.. note::

    Example: dimming a light with a button press

    .. code-block:: yaml

        binary_sensor:
          - platform: gpio
            # ...
            id: my_binary_sensor
            on_press:
              - while:
                  condition:
                    binary_sensor.is_on: my_binary_sensor
                  then:
                    - light.dim_relative:
                        id: light_1
                        relative_brightness: 5%
                        transition_length: 0.1s
                    - delay: 0.1s

.. _light-addressable_set_action:

``light.addressable_set`` Action
--------------------------------

This :ref:`Action <config-action>` allows you to manually set a range of LEDs on an addressable light
to a specific color.

.. code-block:: yaml

    on_...:
      - light.addressable_set:
          id: my_light
          range_from: 0
          range_to: 50
          red: 100%
          green: 0%
          blue: 0%

Configuration variables:

- **id** (**Required**, :ref:`config-id`): The ID of the addressable light to control.
- **range_from** (*Optional*, :ref:`templatable <config-templatable>`, int): The beginning
  of the range of LEDs to control. 0-based indexing. Defaults to 0 (the beginning of the strip).
- **range_to** (*Optional*, :ref:`templatable <config-templatable>`, int): The end of the
  range of LEDs to control - this is a half-open interval. 0-based indexing.
  Defaults to the end of the strip (``num_leds``).
- **red** (*Optional*, :ref:`templatable <config-templatable>`, percentage): The value to
  set the red channel to.
- **green** (*Optional*, :ref:`templatable <config-templatable>`, percentage): The value to
  set the green channel to.
- **blue** (*Optional*, :ref:`templatable <config-templatable>`, percentage): The value to
  set the blue channel to.
- **white** (*Optional*, :ref:`templatable <config-templatable>`, percentage): The value to
  set the white channel to.

.. _light-is_on_condition:
.. _light-is_off_condition:

``light.is_on`` / ``light.is_off`` Condition
********************************************

This :ref:`Condition <config-condition>` checks if the given light is ON or OFF. OFF means
that the light is completely OFF, and ON means that the light is emitting at least a bit of light.

.. code-block:: yaml

    # In some trigger:
    on_...:
      if:
        condition:
          # Same syntax for is_off
          light.is_on: my_light

.. _light-effects:

Light Effects
-------------

ESPHome also offers a bunch of light effects you can use for your lights. The defaults for the
effect parameters are made to work well on their own but of course ESPHome gives you the option to manually change
these parameters.

With ESPHome's light effects system you're basically creating a bunch of entries for the effects dropdown in
Home Assistant. If you wish to have several variants of the same effect you can of course also create multiple
entries with each having a unique name like so:

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          # Use default parameters:
          - random:
          # Customize parameters
          - random:
              name: "My Slow Random Effect"
              transition_length: 30s
              update_interval: 30s
          - random:
              name: "My Fast Random Effect"
              transition_length: 4s
              update_interval: 5s

Random Effect
*************

This effect makes a transition (of length ``transition_length``) to a randomly-chosen color every ``update_interval``.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - random:
          - random:
              name: Random Effect With Custom Values
              transition_length: 5s
              update_interval: 7s

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Random``.
- **transition_length** (*Optional*, :ref:`config-time`): The duration of each transition to start. Defaults to ``5s``.
- **update_interval** (*Optional*, :ref:`config-time`): The interval with which a new color is selected and transitioned
  to.

Strobe Effect
*************

This effect cycles through a list of colors with specific durations.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - strobe:
          - strobe:
              name: Strobe Effect With Custom Values
              colors:
                - state: True
                  brightness: 100%
                  red: 100%
                  green: 90%
                  blue: 0%
                  duration: 500ms
                - state: False
                  duration: 250ms
                - state: True
                  brightness: 100%
                  red: 0%
                  green: 100%
                  blue: 0%
                  duration: 500ms

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Strobe``.
- **colors** (*Optional*, list): A list of colors to cycle through. Defaults to a quick cycle between ON and OFF.

  - **state** (*Optional*, boolean): The ON/OFF state to show. Defaults to ``True``.
  - **brightness** (*Optional*, percentage): The brightness of the light. Defaults to ``100%``.
  - **red** (*Optional*, percentage): The percentage that the red color should be on for RGB lights. Defaults to ``100%``.
  - **green** (*Optional*, percentage): The percentage that the green color should be on for RGB lights. Defaults to ``100%``.
  - **blue** (*Optional*, percentage): The percentage that the blue color should be on for RGB lights. Defaults to ``100%``.
  - **white** (*Optional*, percentage): The percentage that the white color should be on for RGBW lights. Defaults to ``100%``.
  - **duration** (**Required**, :ref:`config-time`): The duration this color should be active.

Flicker Effect
**************

This effect "hovers" around the active color of the light and flickers each color channel a bit.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - flicker:
          - flicker:
              name: Flicker Effect With Custom Values
              alpha: 95%
              intensity: 1.5%

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Flicker``.
- **alpha** (*Optional*, percentage): The percentage that the last color value should affect the light. More
  or less the "forget-factor" of an exponential moving average. Defaults to ``95%``.
- **intensity** (*Optional*, percentage): The intensity of the flickering, basically the maximum amplitude of the
  random offsets. Defaults to ``1.5%``.

Lambda Effect
*************

This effect allows you to write completely custom light effects yourself using :ref:`lambdas <config-lambda>`.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - lambda:
              name: My Custom Effect
              update_interval: 1s
              lambda: |-
                static int state = 0;
                auto call = id(my_light).turn_on();
                // Transtion of 1000ms = 1s
                call.set_transition_length(1000);
                if (state == 0) {
                  call.set_rgb(1.0, 1.0, 1.0);
                } else if (state == 1) {
                  call.set_rgb(1.0, 0.0, 1.0);
                } else if (state == 2) {
                  call.set_rgb(0.0, 0.0, 1.0);
                } else {
                  call.set_rgb(1.0, 0.0, 0.0);
                }
                call.perform();
                state += 1;
                if (state == 4)
                  state = 0;

Configuration variables:

- **name** (**Required**, string): The name of the custom effect.
- **update_interval** (*Optional*, :ref:`config-time`): The interval with which the lambda code is executed.
  A value of ``0ms`` means that the lambda is always executed, without a cool-down. Defaults to ``0ms``.
- **lambda** (**Required**, :ref:`lambda <config-lambda>`): The code to execute. ``static`` variables are
  especially useful.

Addressable Rainbow Effect
**************************

A light effect for individually-addressable LEDs that creates a moving rainbow over the whole LED strip using
the HSV color wheel.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_rainbow:
          - addressable_rainbow:
              name: Rainbow Effect With Custom Values
              speed: 10
              width: 50

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Rainbow``.
- **speed** (*Optional*, int): The speed of the effect, unitless. Defaults to ``10``.
- **width** (*Optional*, int): The "width" of a full-scale rainbow, unitless. Defaults to ``50``.


Addressable Color Wipe Effect
*****************************

A light effect for individually-addressable LEDs that continuously introduces new colors at the beginning of
the strip and shifts them forward every ``add_led_interval``.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_color_wipe:
          - addressable_color_wipe:
              name: Color Wipe Effect With Custom Values
              colors:
                - red: 100%
                  green: 100%
                  blue: 100%
                  num_leds: 1
                - red: 0%
                  green: 0%
                  blue: 0%
                  num_leds: 1
              add_led_interval: 100ms
              reverse: False

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Color Wipe``.
- **colors** (*Optional*, list): The colors to shift in at the beginning of the strip. Defaults to shifting in random
  colors.

  - **red** (*Optional*, percentage): The percentage the red color channel should be on. Defaults to ``100%``.
  - **green** (*Optional*, percentage): The percentage the green color channel should be on. Defaults to ``100%``.
  - **blue** (*Optional*, percentage): The percentage the blue color channel should be on. Defaults to ``100%``.
  - **random** (*Optional*, boolean): If set to ``True``, will overwrite the RGB colors by a new, randomly-chosen
    color each time. Defaults to ``False``.
  - **num_leds** (*Optional*, int): The number of leds of this type to have before moving on to the next color.

- **add_led_interval** (*Optional*, :ref:`config-time`): The interval with which to shift in new leds at the
  beginning of the strip. Defaults to ``100ms``.
- **reverse** (*Optional*, boolean): Whether to reverse the direction of the color wipe. Defaults to ``False``.

Addressable Scan Effect
***********************

Create a single, fast-moving dot moving back and forth an individually-addressable LED strip. The color is chosen by the
currently active light color.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_scan:
          - addressable_scan:
              name: Scan Effect With Custom Values
              move_interval: 100ms

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Scan``.
- **move_interval** (*Optional*, :ref:`config-time`): The interval with which to move the dot one LED forward.
  Defaults to ``100ms``.

Addressable Twinkle Effect
**************************

A light effect for individually-addressable LED strips that randomly chooses some LEDs and let's them bright
up for a moment, like a stars twinkling in the night's sky. The color of the pixels will be chosen by the
currently active light color.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_twinkle:
          - addressable_twinkle:
              name: Twinkle Effect With Custom Values
              twinkle_probability: 5%
              progress_interval: 4ms

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Twinkle``.
- **twinkle_probability** (*Optional*, percentage): The percentage with which, at any time step, a randomly-chosen
  LED should start its twinkle animation.
- **progress_interval** (*Optional*, :ref:`config-time`): The interval with which to progress the effect. This
  affects the duration of a twinkle animation. Defaults to ``4ms``.

Addressable Random Twinkle Effect
*********************************

A light effect similar to ``addressable_twinkle``, but using random colors for each twinkle animation.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_random_twinkle:
          - addressable_random_twinkle:
              name: Random Twinkle Effect With Custom Values
              twinkle_probability: 5%
              progress_interval: 32ms

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Random Twinkle``.
- **twinkle_probability** (*Optional*, percentage): The percentage with which, at any time step, a randomly-chosen
  LED should start its twinkle animation.
- **progress_interval** (*Optional*, :ref:`config-time`): The interval with which to progress the effect. This
  affects the duration of a twinkle animation. Defaults to ``4ms``.


Addressable Fireworks Effect
****************************

A light effect for individually-addressable LED strips that randomly sparks some fireworks at random positions
and lets the sparkles cascade over the LED strip.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_fireworks:
          - addressable_fireworks:
              name: Fireworks Effect With Custom Values
              update_interval: 32ms
              spark_probability: 10%
              use_random_color: false
              fade_out_rate: 120

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Fireworks``.
- **update_interval** (*Optional*, :ref:`config-time`): The interval with which to progress the effect.
  Defaults to ``32ms``.
- **spark_probability** (*Optional*, percentage): The probability to start a new firework spark at a randomly-chosen
  LED at any given time step. Defaults to ``10%``.
- **use_random_color** (*Optional*, boolean): Whether to use random colors for new firework sparks. Defaults to
  using the currently active light color.
- **fade_out_rate** (*Optional*, integer): The rate with which to fade out the LED strip, unitless. Needs to be carefully
  chosen so that the whole strip doesn't light up forever if the fade out rate is too low or that the firework
  sparks do not propagate for a long time. Defaults to ``120``.

Addressable Flicker Effect
**************************

An effect similar to the ``flicker`` effect, but for individually-addressable LED strips. This effect flickers
each LED by its own random amount around the currently active light color.

.. code-block:: yaml

    light:
      - platform: ...
        # ...
        effects:
          - addressable_flicker:
          - addressable_flicker:
              name: Flicker Effect With Custom Values
              update_interval: 16ms
              intensity: 5%

Configuration variables:

- **name** (*Optional*, string): The name of the effect. Defaults to ``Addressable Flicker``.
- **update_interval** (*Optional*, :ref:`config-time`): The time interval for updating the random offsets.
  Defaults to ``16ms``.
- **intensity** (*Optional*, percentage): The intensity of the effect, basically how much the random values can offset
  the currently active light color. Defaults to ``5%``.

Addressable Lambda Effect
*************************

This effect allows you to access each LED individually in a custom light effect.

You're passed in one variable: ``it`` - an :apiclass:`AddressableLight <light::AddressableLight>`
instance (see API reference for more info).

.. code-block:: yaml

    light:
    - platform: ...
      effects:
        - addressable_lambda:
            name: "My Custom Effect"
            update_interval: 16ms
            lambda: |-
              // it.size() - Number of LEDs
              // it[num] - Access the LED at index num.
              // Set the LED at num to the given r, g, b values
              // it[num] = ESPColor(r, g, b);
              // Get the color at index num (ESPColor instance)
              // it[num].get();

              // Example: Simple color wipe
              for (int i = 1; i < it.size(); i++) {
                it[i] = it[i - 1].get();
              }
              it[0] = ESPColor::random_color();

              // Bonus: use .range() and .all() to set many LEDs without having to write a loop.
              it.range(0, 50) = ESPColor::BLACK;
              it.all().fade_to_black(10);

Examples of this API can be found here:
https://github.com/esphome/esphome/blob/dev/esphome/components/light/addressable_light_effect.h
(the built-in addressable light effects).

Automation Light Effect
***********************

Additionally to the ``lambda`` and ``addressable_lambda`` light effects, effects can also
be written through ESPHome's :ref:`Automation <automation>` system with the ``automation``
effect type.

The automation given in the ``sequence`` block will be repeatedly executed until the effect
is stopped by the user.

.. code-block:: yaml

    light:
    - platform: ...
      id: my_light
      effects:
        - automation:
            name: Custom Automation Effect
            sequence:
              - light.addressable_set:
                  id: my_light
                  red: 100%
                  green: 100%
                  blue: 100%
              - delay: 100ms
              - light.addressable_set:
                  id: my_light
                  range_from: 0
                  range_to: 20
                  red: 100%
                  green: 0%
                  blue: 0%

Configuration variables:

- **name** (*Optional*, string): The name of the effect.
- **sequence** (*Optional*, :ref:`Action <config-action>`): The actions to perform in sequence
  until the effect is stopped.

See Also
--------

- :apiref:`light/light_state.h`
- `WS2812FX library <https://github.com/kitesurfer1404/WS2812FX>`__ by `@kitesurfer1404 <https://github.com/kitesurfer1404>`__
- :ghedit:`Edit`

.. toctree::
    :maxdepth: 1
    :glob:

    *