// step is one twenty-fifth of the smallest dimension of the screen, // rounded to the nearest integer step = round(min(width, height)/25) // outer loop iterates x from 0 to the width of the screen loop(0, width, step, x { // inner loop iterates y from 0 to the height of the screen loop(0, height, step, y { // draw a rectangle and fill it a random shade of gray fill_rectangle(x, y, x+step, y+step, random('gray')) }) })