var time;



function setup() {

  createCanvas(windowWidth,

               windowHeight);

  noFill();



  time = 0.5;

}



function draw() {

  background(123, 123, 123);



  var num = 30;

  for (var i = 0; i < num; i = i + 1) {

    var R = i * (270 / num);

    var G = 160 - i * (247 / num);

    var B = 250 - i * (200 / num);

    stroke(R, G, B);



    var x = windowWidth / 2;

    var y = windowHeight / 2;

    var spX = 0.3 * i * windowWidth / num;

    var spY = 0.3 * i * windowHeight / num;

    // var dia = spX;

    var dia = spX * sin(0.1 * i + time);

    stamp(x, y, spX, spY, dia);

  }



  time = time + 0.05;

}



function stamp(x, y, spaceX, spaceY, diameter) {

  ellipse(x - spaceX, y - spaceY, diameter);

  ellipse(x - spaceX, y + spaceY, diameter);

  ellipse(x + spaceX, y - spaceY, diameter);

  ellipse(x + spaceX, y + spaceY, diameter);

}