rook_battlement.scad

module rook_battlement(height, radius) {
  neck_radius = radius;
  battlement_radius = 1.4 * radius;
  inner_battlement_radius = 0.6 * battlement_radius;

  cylinder(0.2 * height, neck_radius, battlement_radius);
  translate([0, 0, 0.2 * height]) {
    difference() {
      // the battlement
      cylinder(0.8 * height, battlement_radius, battlement_radius);

      // cut out the loopholes
      for (i = [0:5]) {
        rotate(a = [0, 0, i * 360 / 6]) 
          translate([-1.5, 0, 0.5 * height])
            cube([3, 10, 4]);
      }

      // cut out circular space at top
      translate([0, 0, 0.5 * height]) {
        cylinder(height, inner_battlement_radius, inner_battlement_radius);
        sphere(inner_battlement_radius);
      }
    }
  }
}