// import libraries
import java.awt.Frame;
import java.awt.BorderLayout;
import processing.serial.*;

// Serial port to connect to
String serialPortName = "COM3";


/* SETTINGS END */

Serial serialPort; // Serial port object


void setup() {
  size(900,900);
  noStroke();

    serialPort = new Serial(this, serialPortName, 9600);
}

byte[] inBuffer = new byte[50]; // holds serial message

void draw() {
      background(0);
  if (serialPort.available() > 0) {
    float[] x= new float[2];
    String myString = "";
      try {
        serialPort.readBytesUntil('r', inBuffer);
      }
      catch (Exception e) {
      }
      myString = new String(inBuffer);
      String[] nums = split(myString, ' ');
        try {
            x[0] = float(nums[0]);    //X
            x[1] = float(nums[1]);    //Y
        }
        catch (Exception e) {
        }
      ellipse(x[0]+500, x[1]+500, 70, 70);      //+500 to make the circle in the middle of interface
  }
  }

Serial.print(xf,DEC);        //méthode 1
Serial.print(" ");
Serial.print(yf,DEC);
Serial.print('r');