private Direction FindValidConnections(Direction dir, Point loc)
{
var list = new List<Direction>();
var startDir = dir;
dir = dir.TurnLeft();
for (var i = 0; i < DirectionHelpers.Directions.Count() - 1; i++)
{
var newLoc = dir.GetLocation(loc);
if (newLoc.X >= 0 && newLoc.X < _cells.GetLength(0) && newLoc.Y >= 0 && newLoc.Y < _cells.GetLength(1))
{
var cell = _cells[newLoc.X, newLoc.Y];
if (cell.Type == CellType.None || cell.Openings.Facing(dir))
{
list.Add(dir);
}
}
dir = dir.TurnRight();
}
var connectsToMake = list.Count > 0 ? _random.Next(1, list.Count + 1) : 0;
var validConnections = list.Take(connectsToMake).Concat(new[] { startDir.TurnAround() }).ToArray();
// close the openings in the neighbor cells that we didn't make
foreach (var connectToUndo in list.Skip(connectsToMake))
{
var newLoc = connectToUndo.GetLocation(loc);
var dirToUndo = connectToUndo.TurnAround();
_cells[newLoc.X, newLoc.Y].Openings ^= dirToUndo;
}
return validConnections.ToDirectionFlag();
}
public void Generate(ITileMap map)
{
_random = new MersennePrimeRandom(_params.Seed);
var w = map.Width / CellSize;
var h = map.Height / CellSize;
_cells = new Cell[w, h];
var startLoc = new Point { X = w / 2, Y = h / 2 };
_cells[startLoc.X, startLoc.Y] = Cell.FourWayRoom();
if (_params.Exits)
{
_cells[startLoc.X, startLoc.Y].Attributes = AttributeType.Entry;
}
var unprocessed = new Queue<Point>();
unprocessed.Enqueue(startLoc);
while (unprocessed.Count > 0)
{
var location = unprocessed.Dequeue();
var cell = _cells[location.X, location.Y];
foreach (var opening in cell.Openings.ToDirectionsArray())
{
var newLocation = opening.GetLocation(location);
var newCell = DetermineCellType(newLocation, opening);
if (newCell.Type != CellType.None)
{
_cells[newLocation.X, newLocation.Y] = ApplyAttributes(newCell);
unprocessed.Enqueue(newLocation);
}
}
}
var secondExitPlaced = !_params.Exits;
var chance = 10;
for (var x = 0; x < _cells.GetLength(0); x++)
for (var y = 0; y < _cells.GetLength(1); y++)
{
var cell = _cells[x, y];
if (!secondExitPlaced)
{
var spawnExit = _random.Chance(chance);
if (cell.Type != CellType.None && ((x <= w * 0.15) || (x >= w * 0.65)) && spawnExit)
{
cell.Attributes = AttributeType.Exit;
secondExitPlaced = true;
}
else if (!spawnExit)
{
chance += (int)(chance * 0.25f);
}
}
cell.Fill(x, y, map, _params);
}
}
// pick a cell type that will connect as many rooms as possible
private Cell DetermineCellType(Point location, Direction direction)
{
var locationInBounds = location.X >= 0 && location.X < _cells.GetLength(0) && location.Y >= 0 && location.Y < _cells.GetLength(0);
if (locationInBounds && _cells[location.X, location.Y].Type == CellType.None)
return new Cell
{
Type = _random.Chance(_params.RoomChance) ? CellType.Room : CellType.Corridor,
Openings = FindValidConnections(direction, location),
Attributes = AttributeType.None,
};
return default(Cell);
}
