gistfile1.java

void setup() {
  size(500, 500);
  noFill();
  strokeWeight(3);
  strokeJoin(BEVEL);
}

float th1, th2, r, x, y, t;
int N = 16;

void draw() {
  background(0);
  t = map(frameCount, 0, 48, 0, TWO_PI);
  stroke(255);
  beginShape();
  for (int i=0; i<N; i++) {
    th1 = map(i, 0, N, 0, 3*TWO_PI);
    th2 = map(i, 0, N, 0, 2*TWO_PI);
    r = map(sin(t+th2), -1, 1, 140, 180);
    x = width/2 + r*cos(th1);
    y = height/2 + r*sin(th1);
    vertex(x, y);
  }
  endShape(CLOSE);
}