patience in pixels

let n = 150;
function setup() {
  c = max(600, min(windowWidth * 0.9, windowHeight * 0.9));
  createCanvas(c, c);
  n = int(random(50, 120));
  rectMode(CENTER);
  d = c / n;
  stroke(20, 40, 50);
  strokeWeight(0.5);
  angleMode(DEGREES);
  rn = int(random(10, 40));
}

function draw() {
  background(10, 30, 40);
  translate(c / 2, c / 2);
  t = frameCount;
  for (let i = 0; i <= width; i += d) {
    for (let j = 0; j <= height; j += d) {
      x = -c / 2 + i;
      y = -c / 2 + j;

      dp = dist(x, y, 0, 0);
      b = atan(y / dp);
      if (abs((dp % rn) * abs(cos(t / 10))) < 5) {
        dp2 = 100 * sin(b + t);
      } else if (int(b + rn * cos(t + b - dp)) % rn == 0) {
        dp2 = -100 * sin(b + t / 2);
      } else {
        dp2 = 0;
      }

      col = map(dp, -c / 2, c / 2, 0, 255) + dp2;

      fill(col / 7, col / 2, col / 1.5);

      rect(x, y, d, d);
    }
  }
  t = frameCount;
  push();
  border();
  pop();
}

function border() {
  push();
  noFill();
  stroke(20, 50, 60);
  strokeWeight(4);
  rect(0, 0, width - 20, height - 20);
  pop();
}

function mousePressed() {
  frameCount = 0;
  setup();
  draw();
}

function keyPressed() {}

function windowResized() {
  setup();
  draw();
}