// More: https://itp.nyu.edu/camp2019/session/55

​

const myNamePrefix = 'Twiz';

const optionalServiceUUID = 0x1901; // or '00001901-0000-1000-8000-00805f9b34fb';

​

var IMU_char;

var valueX = 0, valueY = 0, valueZ = 0;

​

function connect() {

  let options = {

    filters: [{

      optionalServices: [optionalServiceUUID],

      namePrefix: myNamePrefix

    }]}

​

  console.log('Requesting Bluetooth Device...');

​

  navigator.bluetooth.requestDevice(options)

  .then(device => {

    console.log('Got device', device.name);

    return device.gatt.connect();

  })

  .then(server => {

      console.log('Getting Service...');

      return server.getPrimaryService(optionalServiceUUID);

    })

    .then(service => {

      console.log('Getting Characteristics...');

      // Get all characteristics.

      return service.getCharacteristics();

    }) 

    .then(characteristic => {

    myCharacteristic = characteristic;

    return myCharacteristic.startNotifications().then(_ => {

      log('> Notifications started');

      myCharacteristic.addEventListener('characteristicvaluechanged',

          handle_IMU);

    });

  })

  /*

    .then(characteristics => {

      console.log('Got Characteristics');

      IMU_char = characteristics;

​

      IMU_char.startNotifications();

      console.log('> Notifications started');

​

      IMU_char.addEventListener('characteristicvaluechanged', handle_IMU);

      console.log('addEventListener() ok');

    }) */

    .catch(error => {

      console.log('Argh! ' + error);

    });

  }

​

​

function handle_IMU(event) {

  valueX = event.target.value.getUint8(0);

  console.log('> X-Axis: ' + valueX);

}

​

​

function setup() {

  createCanvas(500, 400, WEBGL);

  connect();

}

​

function draw() {

  background(250);

  normalMaterial();

  push();

  rotateX(valueX * 0.01);

  rotateY(valueY * 0.01);

  rotateZ(valueZ * 0.01);

  box(100, 100, 100);

  pop();

}

​

/*

​

function handleNotifications(theData) {

  console.log(theData.length);

  if(theData.length==12) {

              var values = [];

              for(var k=0;k<theData.length;k+=2) {

                  values.push(theData.readInt16BE(k, 2)); // signed int

              }

        debug('data',

              peripheral.advertisement.localName+"\t"+values[0]+

              ", "+values[1]+

              ", "+values[2]+

              ", "+values[3]+

              ", "+values[4]+

              ", "+values[5]);

​

              var n = Math.pow(2, 16);

              var rad = 0.0174533;

              var ax = (values[0] * 4.0)/n;

              var ay = (values[1] * 4.0)/n;

              var az = (values[2] * 4.0)/n;

​

              ex = rad * (values[3] * 360.0)/n;

              ey = rad * (values[4] * 360.0)/n;

              ez = rad * (values[5] * 360.0)/n;

  console.log(theData);

  }

}

​

*/