protected static SpawnList <ListPathTraversalNode> GetPossibleExpansions(FloorPlan floorPlan, List <RoomHallIndex> candList) { // get all probabilities. // the probability of an extension is the distance that the target room is from the start room, in rooms var expansions = new SpawnList <ListPathTraversalNode>(); for (int nn = 0; nn < candList.Count; nn++) { // find the room to connect to // go through all sides of all rooms (randomly) RoomHallIndex chosenFrom = candList[nn]; IFloorRoomPlan planFrom = floorPlan.GetRoomHall(chosenFrom); // exhausting all possible directions (randomly) foreach (Dir4 dir in DirExt.VALID_DIR4) { bool forbidExtend = false; foreach (RoomHallIndex adjacent in planFrom.Adjacents) { Rect adjRect = floorPlan.GetRoomHall(adjacent).RoomGen.Draw; if (planFrom.RoomGen.Draw.GetScalar(dir) == adjRect.GetScalar(dir.Reverse())) { forbidExtend = true; break; } } if (!forbidExtend) { // find a rectangle to connect it with ListPathTraversalNode?expandToResult = GetRoomToConnect(floorPlan, chosenFrom, dir); if (expandToResult is ListPathTraversalNode expandTo) { int prb = floorPlan.GetDistance(expandTo.From, expandTo.To); if (prb < 0) { expansions.Add(expandTo, 1); } else if (prb > 0) { expansions.Add(expandTo, prb); } } } } } return(expansions); }