function square_corners(width, height, rounding = 0) = [
    [width / 2 - rounding, height / 2 - rounding],
    [-width / 2 + rounding, height / 2 - rounding],
    [width / 2 - rounding, -height / 2 + rounding],
    [-width / 2 + rounding, -height / 2 + rounding],
];

module corner(vector = [0, 0], rounding = 0, squared = false) {
    translate(vector) {
        if (squared) {
            square([rounding * 2, rounding * 2], center = true);
        } else {
            circle(r = rounding);
        }
    }
}