float xincr, yincr, dst;

void setup() {
  //size(600, 600);
  fullScreen();
  background(60);
  dst = height/5.5;
  strokeWeight(2);
}

void draw() {
  fill(0);//40
  rect(0, 0, width, height);

  translate(width/2, height/2);
  xincr += 0.01;
  yincr += 0.005;
  float yincr2 = yincr;
  for (float y = -dst; y <= dst; y += 3) {
    yincr2 += 0.01;
    float xincr2 = xincr;
    for (float x = -dst; x <= dst; x += 3) {
      xincr2 += 0.01;
      drawSquare(x, y, noise(xincr2*(mouseX-width/2)/2000, yincr2*(mouseY-height/2)/2000));
    }
  }
}

void drawSquare(float x, float y, float noiseFactor) {
  stroke(0, 175);
  if (noiseFactor * 450 > 255) fill(255);
  else fill(noiseFactor * 450);
  rect(x * noiseFactor * 4, y * noiseFactor * 4, 5, 5);
}