redBall.pde

void setup() {
  size(800, 800, P2D);
}

void draw() {
  float t = radians(frameCount);
  int detail = 50;
  float whiteRadius = 150+150*sin(t);
  float redRadius = 350;
  background(0);
  translate(width/2, height/2);
  beginShape(TRIANGLE_STRIP);
  noStroke();
  for (int i = 0; i <= detail; i++) {
    float a = map(i, 0, detail, 0, TAU);
    float x = whiteRadius * cos(a);
    float y = whiteRadius * sin(a);
    fill(255, 0, 0);
    vertex(x, y);
    fill(255);
    vertex(0, 0);
  }
  endShape();
  
  beginShape(TRIANGLE_STRIP);
  noStroke();
  for (int i = 0; i <= detail; i++) {
    float a = map(i, 0, detail, 0, TAU);
    float x0 = redRadius * cos(a);
    float x1 = whiteRadius * cos(a);
    float y0 = redRadius * sin(a);
    float y1 = whiteRadius * sin(a);
    fill(255, 0, 0);
    vertex(x0, y0);
    vertex(x1, y1);
  }
  endShape();
}