Logitech Litra

This JavaScript driver allows you to control USB-connected Logitech Litra Glow and Logitech Litra Beam lights using a CLI and from your JavaScript code.

With this driver, you can:

• Turn your light on and off
• Check if the light is on or off
• Set and get the brightness of your light
• Set and get the temperature of your light

Compatibility

This library:

• only works with Litra devices connected via USB. Logitech Litra Beam devices connected via Bluetooth are not supported.
• is only tested on macOS Monterey (12.5) and Windows 11. It's powered by node-hid, which is compatible with other macOS versions, Windows and Linux, so it would be expected to work there too, but your mileage may vary 🙏

Using as a command line tool

Make sure you have Node.js available on your machine, and then install the package with npm install -g litra.

With the package installed:

• Use the litra-on, litra-off and litra-toggle commands to turn your light on and off.
• Use the litra-brightness command to set your Litra's brightness to a percentage of its maximum (e.g. litra-brightness 90).
• Use the litra-brightness-lm command to get or set your Litra's brightness to a value in Lumen (e.g. litra-brightness 250).
• Use the litra-temperature-k command to get or set your Litra's temperature to a value in Kelvin (e.g. litra-temperature-k 6500).

All of the these commands support a --serial-number/-s argument to specify the serial number of the device you want to target. If you only have one Litra device, you can omit this argument. If you have multiple devices, we recommend specifying it. If it isn't specified, the "first" device will be picked, but this isn't guaranteed to be stable between command runs.

You can also use:

• litra-devices to list Litra devices connected to your machine, including in JSON format with --json
• litra-identify to interactively identify the serial numbers of your Litra devices, if you have multiple connected

Each CLI command can also be called with --help for more detailed documentation.

Using as a JavaScript library

Installation

Simply add the litra Node.js package to your package.json and install it:

npm install --save litra

Usage

Checking if a Litra device is plugged in

The findDevice function checks your computer to find whether a Logitech Litra device is plugged in.

If it is, it returns an object representing the device, which you can pass into other function. If it isn't, it returns null.

import { findDevice } from 'litra';

const device = findDevice();

if (device) {
  console.log(`Found a ${device.type} device connected`);

  // Do something
} else {
  // Blow up
}

If you're a huge fan of Litra devices and you have multiple plugged in at the same time, use findDevices instead:

const devices = findDevices();

if (devices.length > 0) {
  console.log(`Found ${devices.length} devices connected`);
  for (let i = 0; i < devices.length; ++i) {
    console.log(`Device ${i + 1}: ${devices[i].type}`);
  }

  // Do something
} else {
  // Blow up
}

Turning your Litra device on or off

Find your device with findDevice, and then use the simple turnOn and turnOff functions. They just take one parameter: the device.

You can also use the isOn function to check if your device is on/off.

import { findDevice, turnOff, turnOn, isOn } from 'litra';

const device = findDevice();

// Turn your light on, then turn it off again after 5 seconds
if (device) {
  turnOn(device);

  if (isOn(device)) {
    console.log(
      `Your device is now on!`,
    );
  }

  setTimeout(() => {
    turnOff(device)

    if (!isOn(device)) {
      console.log(
        `Your device is now off!`,
      );
    }
  }, 5000));
}

Alternatively, you can use the toggle function to switch your device on if it's off and vice-versa.

import { findDevice, toggle } from 'litra';

const device = findDevice();

// Turn your light on if it's currently off, and vice-versa
toggle();

Setting and getting the brightness of your Litra device

You can set the brightness of your Litra device, measured in Lumen, using the setBrightnessInLumen function.

To get the current brightness of your device, use the getBrightnessInLumen function.

The Litra Glow supports brightness between 20 and 250 Lumen. The Litra Beam supports brightness between 20 and 400 Lumen.

You can programatically check what brightness levels are supported by your device. Once you know what brightness levels are supported, you can set the brightness in Lumen. If you try to set a value that isn't allowed by your device, an error will be thrown:

import {
  findDevice,
  getMaximumBrightnessInLumenForDevice,
  getMinimumBrightnessInLumenForDevice,
  setBrightnessInLumen,
} from 'litra';

const device = findDevice();

if (device) {
  const minimumBrightness = getMinimumBrightnessInLumenForDevice(device);
  const maximumBrightness = getMaximumBrightnessInLumenForDevice(device);

  console.log(
    `The minimum allowed brightness is ${minimumBrightness} and the maximum is ${maximumBrightness}`,
  );

  setBrightnessInLumen(device, 150);

  // Will return 150
  getBrightnessInLumen(device);
}

You can also set brightness level to a percentage with setBrightnessPercentage if you don't want to think in Lumen:

import { findDevice, setBrightnessPercentage } from 'litra';

const device = findDevice();

if (device) {
  setBrightnessPercentage(device, 75);
}

Setting the temperature of your Litra device

You can set the temperature of your Litra device, measured in Kelvin, using the setTemperatureInKelvin function.

The getTemperatureInKelvin function can be used to get the current temperature your device is set to.

Both the Litra Glow and Litra Beam support temperatures which are multiples of 100 between 2700 and 6500 Kelvin (i.e.. 2700, 2800, 2900, etc.).

You can check programatically what temperature levels are supported by your device. Once you know what temperature levels are supported, you can set the temperature in Kelvin. If you try to set a value that isn't allowed by your device, an error will be thrown:

import {
  findDevice,
  getAllowedTemperaturesInKelvinForDevice,
  getMaximumTemperatureInKelvinForDevice,
  getMinimumTemperatureInKelvinForDevice,
  setTemperatureInKelvin,
} from 'litra';

const device = findDevice();

if (device) {
  const minimumTemperature = getMinimumTemperatureInKelvinForDevice(device);
  const maximumTemperature = getMaximumTemperatureInKelvinForDevice(device);
  const allowedTemperatures = getAllowedTemperaturesInKelvinForDevice(device);

  console.log(
    `The minimum allowed temperature is ${minimumTemperature} and the maximum is ${maximumTemperature}`,
  );
  console.log(`The following temperature are allowed: ${allowedTemperatures.join(', ')}`);

  setTemperatureInKelvin(device, 6500);

  // Should return 6500
  getTemeratureInKelvin(device);
}

Use the RGB side

Litra beam LX also has a RGB side. You can use the setRGBColor function to set the color of the RGB side. By setting all to zero you can turn off the RGB side completely.

import {
  findDevice,
  setRGBColor
} from 'litra';

const device = findDevice();

if (device) {
  setRGBColor(device, 255, 0, 0); // red
}

Per-zone configuration. Litra Beam LX has 7 different programmable zones. You can use the setZoneColorRGB function to set the RGB color of a specific zone. By setting all to zero you can turn off the RGB side completely. Please run setRGBColor(device, 0, 0, 0) before OR set all the 7 zones everytime, otherwise the device might behave strangely.

The below example will set the central zone to blue and all the rest will be off.

import {
  findDevice,
  setRGBColor,
  setZoneColorRGB
} from 'litra';

const device = findDevice();

if (device) {
  setZoneColorRGB(device, 1, 0, 0, 0);
  setZoneColorRGB(device, 2, 0, 0, 0);
  setZoneColorRGB(device, 3, 0, 0, 0);
  setZoneColorRGB(device, 4, 0, 0, 255);
  setZoneColorRGB(device, 5, 0, 0, 0);
  setZoneColorRGB(device, 6, 0, 0, 0);
  setZoneColorRGB(device, 7, 0, 0, 0);
}

Using with Raycast

Litra integrates with Raycast so you can manage your Litra device from the Raycast launcher.

To use the integration, just install this package globally with npm install -g litra, add the "Logitech Litra" extension from the Raycast Store (source code here), find the "Manage Devices" command and then follow the instructions to configure the extension.

Using with Oversight

Litra integrates with Oversight to allow you to automatically turn your Litra device on or off when your webcam turns on and off. This allows you to be illuminated every time you join a video call!

To use the integration, just point Oversight at the litra-oversight CLI command. You can find the path of the binary on Unix machines by running which litra-oversight from a terminal after installing this package.

If you have multiple Litra devices, they will all be targeted when litra-oversight runs