How to use the robotjs.getScreenSize function in robotjs

updateMouse() {
		// periodically poll the system for mouse coordinates
		// console.log('updateMouse');
		var mouse = robot.getMousePos();
		this.mouse = {
			x: mouse.x,
			y: mouse.y
		};

		this.screenSize = robot.getScreenSize();
	}

using Socket.io version 1.0 or later (http://socket.io/)
using robot.js to control mouse

see ~/0/2015/p5/configSensact v1 for example of talking to serial port
https://github.com/voodootikigod/node-serialport

*/

//Move the mouse across the screen as a sine wave.
var robot = require("robotjs");

//Speed up the mouse.
robot.setMouseDelay(2);

var twoPI = Math.PI * 2.0;
var screenSize = robot.getScreenSize();
var height = (screenSize.height / 2) - 10;
var width = screenSize.width;

for (var x = 0; x < width; x++)
{
    y = height * Math.sin((twoPI * x) / width) + height;
    robot.moveMouse(x, y);
}


var express = require('express'); // include express.js

var io = require('socket.io'), // include socket.io
  app = express(), // make an instance of express.js
  server = app.listen(1871), // start a server with the express instance
  socketServer = io(server); // make a socket server using the express server

var robot = require('robotjs');

// Cache screen size
var screenSize = robot.getScreenSize();

var Scanner = require ('./Scanner');

// COLOR DEFINITIONS
// This is the Dino's colour, also used by Obstacles.
var COLOR_DINOSAUR = '535353';
var DARK_COLOR_DINO = 'ACACAC';

var GameManipulator = {

  // Stores the game position (Globally)
  offset: null,
  width: null,

  // Stores points (jumps)
  points: 0,

var dialog = require('dialog');
var robot = require('robotjs');
var DEBUG_MODE = require('./Enums').DEBUG_MODE;
var gui = window.require('nw.gui');

var w = robot.getScreenSize().width;
var h = robot.getScreenSize().height;

var resolution = w + 'x' + h;
var aspect = w / h;

var basePosition = {
	x: w / 2,
	y: h * 0.44
};

function showAllDevTools() {
	for (var i in global.__nwWindowsStore) {
		global.__nwWindowsStore[i].showDevTools();
	}
}

const handleMouse = (eventItem) => {
  const x = eventItem.data.x;
  const y = eventItem.data.y;

  const screenSize = robot.getScreenSize();

  if (x > 0 && x < screenSize.width && y > 0 && y < screenSize.height) {
    robot.moveMouse(x, y);
  }
};

setTimeout(function () {
            length = length * 100;

            var screen = robot.getScreenSize();
            var x = screen.width / 2;
            var y = screen.height / 2;

            var n = 0;
            var intervalId = setInterval(function () {
                robot.moveMouse(x, y);

                if (++n == length)
                    clearInterval(intervalId);
            }, 1);
        }, wait * 1000);

var dialog = require('dialog');
var robot = require('robotjs');
var DEBUG_MODE = require('./Enums').DEBUG_MODE;
var gui = window.require('nw.gui');

var w = robot.getScreenSize().width;
var h = robot.getScreenSize().height;

var resolution = w + 'x' + h;
var aspect = w / h;

var basePosition = {
	x: w / 2,
	y: h * 0.44
};

function showAllDevTools() {
	for (var i in global.__nwWindowsStore) {
		global.__nwWindowsStore[i].showDevTools();
	}
}

function hideAllGUIWindows() {