analogread_pacman_1023.pde

import processing.serial.*;

Serial serial;
PFont font;

void setup() {
  size(600, 600);
  serial = new Serial(this, "/dev/cu.usbmodem1421", 115200);  

  font = createFont("Impact", 32);
}

int sensor_val;
int read_sensor_val() {
  while (serial.available () > 0) {
    String str = serial.readStringUntil(10);
    if (str != null) {
      str = trim(str);
      sensor_val = int(str);
    }
  }
  return sensor_val;
}

void draw() {
  int val = read_sensor_val();

  background(0, 0, 64);

  fill(255,255,255);
  noStroke();
  textFont(font);
  text("val=" + val, 30, 30);

  fill(255, 255, 0);
  noStroke();
  
  float p = val / 1023.0f;
  float angle = PI * p;

  arc(300, 300, 400, 400, -angle, angle, PIE);

}