tower {
  flags CIRCLE
  size_x 12~16
  size_y 9~14
  id_1 0
  relations {
    tower_walls {
      flags CIRCLE|BORDER|OVERLAP
    }
    hole {
      x 50%
      y 50%
    }
  }
}
tower_walls {
  flags BORDER
  size_x 100%
  size_y 100%
  id_1 1
}
hole {
  flags RECT|IGNORE_EMPTY
  size_x 100%
  id_1 0
  replace {
    id_1 1
  }
}

start {
  size_x 40
  size_y 20
  id_1 0
  relations {
    tower {
      flags ORIGIN
      x 50%
      y 50%
    }
  }
}