既に十分にわかりやすいんだけど
/*
* AAでマップを図示
*/
trait originAndPit extends installations  {
  val pitPlace = Point(1, 1)
  initTile(field, origin, players(0))
  initTile(field, pitPlace, players(0))
  aroundPoints(origin).foreach(initTile(field, _, players(0)))
  aroundPoints(pitPlace).foreach(initTile(field, _, players(0)))
  field(origin).robots = 1
  field(pitPlace).robots = 20
}

"allow to accept building a \"square\"" in new installations with originAndPit {
みたいにするとどうかな？