Week 11 – Assignment

Video

P5.js code

let velocity;
let gravity;
let position;
let acceleration;
let wind;
let drag = 0.99;
let mass = 50;

let didTouch = 0;

function setup() {
  createCanvas(640, 360);
  noFill();
  position = createVector(width/2, 0);
  velocity = createVector(0,0);
  acceleration = createVector(0,0);
  gravity = createVector(0, 0.5*mass);
  wind = createVector(0,0);
}

function draw() {
  background(255);
  applyForce(wind);
  applyForce(gravity);
  velocity.add(acceleration);
  velocity.mult(drag);
  position.add(velocity);
  acceleration.mult(0);
  ellipse(position.x,position.y,mass,mass);
  if (position.y > height-mass/2) {
      didTouch = 1;
      velocity.y *= -0.9;  // A little dampening when hitting the bottom
      position.y = height-mass/2;
  } else {
    didTouch = 0
  }
}

function applyForce(force){
  // Newton's 2nd law: F = M * A
  // or A = F / M
  let f = p5.Vector.div(force, mass);
  acceleration.add(f);
}

function keyPressed(){
  if (keyCode==LEFT_ARROW){
    wind.x=-1;
  }
  if (keyCode==RIGHT_ARROW){
    wind.x=1;
  }
  if (key==' '){
    mass=random(15,80);
    position.y=-mass;
    position.x = width / 2
    velocity.mult(0);
  }
  
  if (key == 's') {
    setUpSerial();
  }
}

// This function will be called by the web-serial library
// with each new *line* of data. The serial library reads
// the data until the newline and then gives it to us through
// this callback function
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 == 1) {
      // only store values here
      // do everything with those values in the main draw loop
      
      // We take the string we get from Arduino and explicitly
      // convert it to a number by using int()
      // e.g. "103" becomes 103
      windValue = int(fromArduino[0]);
      wind = createVector(map(windValue, 0, 1023, -2, 2), 0)
    }

    //////////////////////////////////
    //SEND TO ARDUINO HERE (handshake)
    //////////////////////////////////
    let sendToArduino = didTouch + "\n";
    print(sendToArduino)
    writeSerial(sendToArduino);
  }
}

Arduino code

// Week 11.2 Example of bidirectional serial communication

// Inputs:
// - A0 - sensor connected as voltage divider (e.g. potentiometer or light sensor)
// - A1 - sensor connected as voltage divider 
//
// Outputs:
// - 2 - LED
// - 5 - LED

int ledPin = 5;
int potPin = A2;

void setup() {
  // Start serial communication so we can send data
  // over the USB connection to our p5js sketch
  Serial.begin(9600);

  // We'll use the builtin LED as a status output.
  // We can't use the serial monitor since the serial connection is
  // used to communicate to p5js and only one application on the computer
  // can use a serial port at once.
  pinMode(LED_BUILTIN, OUTPUT);

  // Outputs on these pins
  pinMode(ledPin, OUTPUT);

  // Blink them so we can check the wiring
  digitalWrite(ledPin, HIGH);
  delay(200);
  digitalWrite(ledPin, LOW);



  // start the handshake
  while (Serial.available() <= 0) {
    digitalWrite(LED_BUILTIN, HIGH); // on/blink while waiting for serial data
    Serial.println("0"); // send a starting message
    delay(300);            // wait 1/3 second
    digitalWrite(LED_BUILTIN, LOW);
    delay(50);
  }
}

void loop() {
  // wait for data from p5 before doing something
  while (Serial.available()) {
    digitalWrite(LED_BUILTIN, HIGH); // led on while receiving data

    int ledLight = Serial.parseInt();
    if (Serial.read() == '\n') {
      digitalWrite(ledPin, ledLight);
      int sensor = analogRead(potPin);
      delay(5);
      Serial.println(sensor);
    }
  }
  digitalWrite(LED_BUILTIN, LOW);
}