Super hacky Node.js script that lets you control your cursor with a joystick connected to an Arduino, using Johnny-Five and RobotJS

johnny-joystick.js

'use strict'
const five = require('johnny-five')
const board = new five.Board()
const robot = require('robotjs')
const range = 24
const center = range / 2
const threshold = range / 8
let count = 0

robot.setMouseDelay(1)

board.on('ready', function() {
  // Create a new 'joystick' hardware instance.
  const joystick = new five.Joystick({
    // [ x, y ]
    pins: ['A0', 'A1']
  })

  joystick.on('change', function() {
    console.log(count)
    count++
    console.log('Joystick')
    console.log('  x : ', this.x)
    console.log('  y : ', this.y)
    console.log('--------------------------------')

    const xReading = readAxis(this.x)
    const yReading = readAxis(this.y)
    const current = robot.getMousePos()
    robot.moveMouse(current.x + xReading, current.y - yReading)
  })
})

function readAxis(thisAxis) {
  // johnny-five reading ranges from -1 to 1
  // Add one then scale to a (0, range) reading
  let reading = ++thisAxis * (range / 2)

  let distance = reading - center

  if (Math.abs(distance) < threshold) {
    distance = 0
  }

  return distance
}