module pie_slice(radius, start_angle, end_angle) {
    R = radius * sqrt(2) + 1;
    a0 = (4 * start_angle + 0 * end_angle) / 4;
    a1 = (3 * start_angle + 1 * end_angle) / 4;
    a2 = (2 * start_angle + 2 * end_angle) / 4;
    a3 = (1 * start_angle + 3 * end_angle) / 4;
    a4 = (0 * start_angle + 4 * end_angle) / 4;
    m = 2;
    if(end_angle > start_angle) {
      intersection() {
        circle(r=radius);
        polygon([
            [0,0],
            [R * m * cos(a0), R * m * sin(a0)],
            [R * m * cos(a1), R * m * sin(a1)],
            [R * m * cos(a2), R * m * sin(a2)],
            [R * m * cos(a3), R * m * sin(a3)],
            [R * m * cos(a4), R * m * sin(a4)],
            [0,0]
        ]);
      }
    } else {
      pie_slice(radius, end_angle, start_angle);
    }
}