#declare PieceBase =
union {
    intersection {
       sphere { <0, 0, 0>, 3 }
       plane { -y, 0 }
    }
    cylinder { 0, y*0.35, 3.0 pigment { green 0.65 } }
}

#declare Knight = union {
   intersection {
      object { Cylinder_Z
         scale <17.875, 17.875, 1>
         translate <-18.625, 7, 0>
         inverse
      }

      object { Cylinder_Z
         scale <17.875, 17.875, 1>
         translate <18.625, 7, 0>
         inverse
      }

      object { Cylinder_X
         scale <1, 5.1, 5.1>
         translate <0, 11.2, -5>
         inverse
      }

      union {
         plane { y, 0
            rotate 30*x
            translate 9.15*y
         }
         plane { z, 0
            rotate -20*x
            translate 10*y
         }
      }

      union {
         plane { -y, 0
            rotate 30*x
            translate 7.15*y
         }
         plane { y, 0
            rotate 60*x
            translate 7.3*y
         }
      }

      union {
         plane { y, 0
            rotate -45*y
         }
         plane { y, 0
            rotate 45*z
         }
         translate 9*y
      }

      object { Cylinder_Y scale <2, 1, 2> }
      sphere { <0, 7, 0>, 4 }
   }

   sphere { <0, 0, 0>, 1
      scale <2.5, 0.5, 2.5>
      translate <0, 2.8, 0>
   }

   object { PieceBase }
}