[
  {
    "type": "mapgen",
    "method": "json",
    "nested_mapgen_id": "riverside_boat",
    "object": {
      "mapgensize": [ 24, 24 ],
      "place_vehicles": [ { "vehicle": "boats_shore", "x": 12, "y": 1, "chance": 100, "rotation": 90, "status": -1 } ]
    }
  }
]
