let alpha = 255;

let left = 0;

let right = 0;

​

function setup() {

  createCanvas(640, 480);

  textSize(18);

}

​

function draw() {

  // one value from Arduino controls the background's red color

  background(map(rVal, 0, 1023, 0, 255), 255, 255);

​

  // the other value controls the text's transparency value

  fill(255, 0, 255, map(alpha, 0, 1023, 0, 255));

​

  if (!serialActive) {

    text("Press Space Bar to select Serial Port", 20, 30);

  } else {

    text("Connected", 20, 30);

  }

​

  // click on one side of the screen, one LED will light up

  // click on the other side, the other LED will light up

  if (mouseIsPressed) {

    if (mouseX <= width / 2) {

      left = 1;

    } else {

      right = 1;

    }

  } else {

    left = right = 0;

  }

}

​

function keyPressed() {

  if (key == " ") {

    // important to have in order to start the serial connection!!

    setUpSerial();

  }

}

​

function readSerial(data) {

  ////////////////////////////////////

  //READ FROM ARDUINO HERE

  ////////////////////////////////////

​

  if (data != null) {

    // make sure there is actually a message

    // split the message

    let fromArduino = split(trim(data), ",");

    // if the right length, then proceed

    if (fromArduino.length == 2) {

      // only store values here

      // do everything with those values in the main draw loop

      rVal = fromArduino[0];

      alpha = fromArduino[1];

    }

​

    //////////////////////////////////

    //SEND TO ARDUINO HERE (handshake)

    //////////////////////////////////

    let sendToArduino = left + "," + right + "\n";

    writeSerial(sendToArduino);

  }

}

​

//Arudino Code

/*

void setup() {

  Serial.begin(9600);

  pinMode(2, OUTPUT);

  pinMode(5, OUTPUT);

  // start the handshake

  while (Serial.available() <= 0) {

    Serial.println("0,0"); // send a starting message

    delay(300);            // wait 1/3 second

  }

}

​

void loop() {

  // wait for data from p5 before doing something

  while (Serial.available()) {

    int left = Serial.parseInt();

    int right = Serial.parseInt();

    if (Serial.read() == '\n') {

      digitalWrite(2, left);

      digitalWrite(5, right);

      int sensor = analogRead(A0);

      delay(1);

      int sensor2 = analogRead(A1);

      delay(1);

      Serial.print(sensor);

      Serial.print(',');

      Serial.println(sensor2);

    }

  }

}

*/

​