​

function setup() {

  createCanvas(400, 400);

  pg = createGraphics(4000, 4000);

  pg.background(32);

}

​

function draw() {

  pg.ellipse(random(pg.width), random(pg.height), 100, 100);

  image(pg, 0, 0, width, height);

}

​

function mousePressed() {

  pg.save("pg.png");

}