test.pde

size(1024, 500);
background(16,64,128);

noStroke();
fill(32,32,128);

float h = 51;
for (int y = 1; y < height; y += h) {
  float w = y % 41 + 20;
  for (int x = 0; x < width; x += w) {
    rect(x, y, w-10, h-40);
  }    
}