Physical Controller for my OOP Game

I decided to create a physical controller for my simple version of Flappy Bird, that I coded for the OOP assignment. I tried to code a button which will control the movement of the object in the game, and with some help from Rick, I was able FINALLY figure it out! I set up a button state and used it in the draw function, since I have three states for the game – pressing the button will change the button state from 0 to 1 then change the state of the game also from 0 to 1.

Arduino Code:

int buttonPin = 2;
int button;

void setup() {
  Serial.begin(9600);
  Serial.println('0');
  pinMode(buttonPin, INPUT);
}
 
void loop() {
    char inByte=Serial.read();
    button = digitalRead(buttonPin);
    delay(0);
    Serial.println(button);
}

Processing Code:

import processing.serial.*;
Serial myPort;
int state = 0; 
int score=0;
boolean currentState = false;
boolean prevState = false;
int arduinoButton = 0;
bird b = new bird();
pillar[] p = new pillar[3];


void setup(){
 size(500,700);
 
 printArray(Serial.list());
  String portname=Serial.list()[7];
  println(portname);
  myPort = new Serial(this,portname,9600);
  myPort.clear();
  myPort.bufferUntil('\n');
  
 int i; 
 for (i = 0; i < 3; i++){
   p[i]=new pillar(i);
 };
}

void draw(){
  background(0);
  if (arduinoButton == 1 && prevState == false) {
    currentState = true;
    prevState = true;
    state = 1;
  }
  
  if (arduinoButton == 1) {
    b.jump();
  }
  
  if (state==0){
    // intro state
    text("Click to Play",155,240);
    b.move(p);
  }
  
  else if (state==1){
    // start state 
    b.move(p);
    b.drag();
    b.checkCollisions();
    rect(20,20,100,50);
    fill(255);
    text(score,30,58);
  }
  
  else {
    // end state 
    rect(150,100,200,50);
    rect(150,200,200,50);
    fill(255);
    text("game over",170,140);
    text("score",180,240);
    text(score,280,240);
  }
  
  b.drawBird();
  
  for(int i = 0;i<3;i++){
    p[i].drawPillar();
    p[i].checkPosition();
  }
  
  stroke(255);
  textSize(32);
}
void mousePressed(){
  state = 1;
} 

void serialEvent(Serial myPort){
  String s=myPort.readStringUntil('\n');
  s=trim(s);
  if (s!=null){
    arduinoButton = int(s);
  }
  println(arduinoButton);
}