SketchBook

var time;

function setup() {
createCanvas(windowWidth,
windowHeight);
noFill();

time = 0.0;
}

function draw() {
 background(255,255, 255);

var num = 20;
for (var i = 0; i < num; i = i + 1) {
   var R = i * (255 / num);
   var G = 250 - i * (125 / num);
   var B = 64 - i * (155 / num);
stroke(R, G, B);

var x = windowWidth / 2;
var y = windowHeight / 2;
var spX = 0.5 * i * windowWidth / num;
var spY = 0.5 * i * windowHeight / num;
// var dia = spX;
var dia = spX * sin(0.1 * i + time);
stamp(x, y, spX, spY, dia);
}

time = time + 0.01;
}

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);
}