// Based on Listing 4-1, Generative Art

float x, y, radius = 200, centX, centY;

size(500, 500);
background(255);
centX = width / 2;
centY = height / 2;
strokeWeight(5);
stroke(0, 60);
noFill();
ellipse(centX, centY, radius*2, radius*2);
stroke(0);
for (float ang = 0; ang <= 360; ang += 10) {
  float rad = radians(ang);
  x = centX + (radius * cos(rad));
  y = centY + (radius * sin(rad));
  point(x, y);
}