Based on Don Karlsson's Recursive Squares contribution to CodingTrain Community

References:

https://thecodingtrain.com/CodingChallenges/077-recursion.html

https://codepen.io/DonKarlssonSan/pen/PJQvKG

*/

​

let angle = 0;

let iterations = 5;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  rectMode(CORNER);

  strokeWeight(2);

  noStroke();

  fill(255, 125);

}

​

function draw() {

  background(0);

  angle += 0.001;

  let x = width / 2;

  let y = height / 2;

  drawSquare(iterations, x, y);

}

​

function drawSquare(iteration, x, y) {

  if (iteration > 0) {

    iteration--;

​

    push();

    translate(x, y);

    rotate(iteration * angle);

    let windowMin = min(width, height);

    let size = ((iteration / iterations) * windowMin) / 3;

    square(-size / 2, -size / 2, size);

​

    drawSquare(iteration, -size / 2, -size / 2);

    drawSquare(iteration, size / 2, size / 2);

    drawSquare(iteration, size / 2, -size / 2);

    drawSquare(iteration, -size / 2, size / 2);

    pop();

  }

}

​

function windowResized() {

  resizeCanvas(windowWidth, windowHeight);

  background(0);

}

​