createCanvas(400, 400);

}

​

function draw() {

  background(200);

​

  var period = 2000.0; // milliseconds

  var angle = TWO_PI * millis() / period;

​

  var center = width / 2;

  var amplitude = 100;

  var frequency = 1.0;

  var phase = 0;

​

  fill(255,255,200); 

  frequency = 1.0;

  for (var i = 0; i < 4; i++) {

    phase = i * radians(45); 

    var py = 40 + i*40; 

    var px = center + amplitude * sin(phase + frequency * angle);

    ellipse(px, py, 40, 40);

  }

  fill(200,255,255); 

  phase = 0;

  for (var i = 0; i < 4; i++) {

    frequency = i+1;

    var py = 240 + i*40; 

    var px = center + amplitude * sin(phase + frequency * angle);

    ellipse(px, py, 40, 40);

  }

}