​

function setup() {

  createCanvas(400, 400);

  setTimeout(rainbow, 3000);

}

​

function rainbow() {

  createP('rainbow');

  setTimeout(rainbow, 3000);

}

​

function draw() {

  background(0);

  stroke(255);

  line(x, 0, x, height);

  x = x + 3;

  if (x > width) {

    x = 0;

  }

}