Arduino and Processing gives NullPointerException

Processing Electronics (Arduino, etc.)
7

That is because you have commented this:

  //Campus = loadImage("Egbertbackground.jpg");

Try this example and tell me what you are seeing:

Arduino Code < Click to open! 
void setup() 
  {
  Serial.begin(9600);
  delay(500);
  }

int c;

void loop() 
  {
  float angle = c*TWO_PI/360;  
  int x = int(200*cos(angle));
  int y = int(200*sin(angle));
  Serial.print(x);
  Serial.print(',');
  Serial.print(y);
  Serial.print(',');
  Serial.println(c);
  delay(10);        // delay in between reads for stability
  c++;
  if(c>359) c = 0;
  }
Processing Code < Click to open! 
/*
DATE: 23_10_2022
 CREATIVE CHALLENGE 2: EGBERT THE FISH GAME_version_3
 AUTHOR: TAISSIA VISSER
 REFERENCES:
 https://www.youtube.com/watch?v=jUmjbFsA2zw&ab_channel=Crazy-Logic
 */

// Modified by glv for testing. 2022/10/24

// Importing the serial library.
import processing.serial.*;

// Declare serial communication port
Serial myPort;
//String inString;
String[] data = {"0", "0", "0"};    // Array of data received from the serial port

void setup() 
  {
  size (400, 400);
  String myPortName = Serial.list()[5];
  myPort = new Serial(this, myPortName, 9600);
  myPort.bufferUntil('\n');
  //PrintArray(Serial.list());
  }

void draw() {
  //background(Campus);
  background(0);
  int xPos = int(data[0])/2;
  int yPos = int(data[1])/2;
  int Pressed = int(data[2]);
  //image(Egbert, xPos, yPos);
  circle(xPos+200, yPos+200, 30);
}

// will get called every time data comes in
// storing the data string here
void serialEvent(Serial myPort) {
  String inString = myPort.readStringUntil('\n');
  if (inString != null)
    {
    // removing the whitespace
    inString = trim(inString);
  // Splitting the string at the commas and
  // seperating the variables out into an array
    data = split(inString, ",");
    }
}

I initialized data to avoid the null until you received data:
String[] data = {"0", "0", "0"};

Focus on receiving data for now and refine and add to the code later.

I am just helping you along…

What operating system and which version of Processing?

Related:
https://discourse.processing.org/t/text-indicator-not-in-the-right-place/32073/3

The Processing Preferences has something related HiDPI to scaling:

image
image471×755 53.6 KB

I am using W10 and Processing 4.01.

:)

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