public void Generate()
{
InitializeMap();
ClearMap();
Stack <PairRowCol> st = new Stack <PairRowCol>();
System.Random rng = new System.Random();
var currentPos = new PairRowCol {
Row = rng.Next(Height), Col = rng.Next(Width)
};
st.Push(currentPos);
MarkVisited(currentPos);
while (st.Count > 0)
{
var uns = GetUnvisitedNeighbors(currentPos).ToArray();
if (uns.Length > 0)
{
var nextPos = uns[rng.Next(uns.Length)];
Connect(currentPos, nextPos);
st.Push(nextPos);
MarkVisited(nextPos);
currentPos = nextPos;
}
else
{
currentPos = st.Pop();
}
}
CleanWalls();
}
private void Connect(PairRowCol p1, PairRowCol p2)
{
if (p1.Row == p2.Row)
{
if (p1.Col < p2.Col)
{
_map[p1.Row, p1.Col].WallState ^= InvertX ? MazeCell.WallStates.Left : MazeCell.WallStates.Right;
_map[p2.Row, p2.Col].WallState ^= InvertX ? MazeCell.WallStates.Right : MazeCell.WallStates.Left;
}
else if (p1.Col > p2.Col)
{
_map[p1.Row, p1.Col].WallState ^= InvertX ? MazeCell.WallStates.Right : MazeCell.WallStates.Left;
_map[p2.Row, p2.Col].WallState ^= InvertX ? MazeCell.WallStates.Left : MazeCell.WallStates.Right;
}
}
if (p1.Col == p2.Col)
{
if (p1.Row < p2.Row)
{
_map[p1.Row, p1.Col].WallState ^= InvertY ? MazeCell.WallStates.Top : MazeCell.WallStates.Bottom;
_map[p2.Row, p2.Col].WallState ^= InvertY ? MazeCell.WallStates.Bottom : MazeCell.WallStates.Top;
}
else if (p1.Row > p2.Row)
{
_map[p1.Row, p1.Col].WallState ^= InvertY ? MazeCell.WallStates.Bottom : MazeCell.WallStates.Top;
_map[p2.Row, p2.Col].WallState ^= InvertY ? MazeCell.WallStates.Top : MazeCell.WallStates.Bottom;
}
}
}
PairRowCol GetRandomNonBlockedCell(int nRandom = 1)
{
PairRowCol pos = PairRowCol.Create(0, 0);
int iterCnt = 0;
do
{
pos.Row = Random.Range(0, MazeRows);
pos.Col = Random.Range(0, MazeColumns);
} while (iterCnt++ < nRandom && _mg.GetCell(pos).WallState.HasFlag(MazeGenerator.MazeCell.WallStates.All));
return(pos);
}
private IEnumerable <PairRowCol> GetNeighbors(PairRowCol p)
{
var l = new PairRowCol {
Row = p.Row, Col = p.Col - 1
}; // left
var r = new PairRowCol {
Row = p.Row, Col = p.Col + 1
}; // right
var a = new PairRowCol {
Row = p.Row - 1, Col = p.Col
}; // above
var b = new PairRowCol {
Row = p.Row + 1, Col = p.Col
}; // below
return(new[] { l, r, a, b }.Where(ValidPos));
}
private void CleanWalls()
{
for (int row = 1; row < Height; ++row)
{
for (int col = 1; col < Width; ++col)
{
var current = GetCell(PairRowCol.Create(row, col));
var left = GetCell(PairRowCol.Create(row, col - 1));
var above = GetCell(PairRowCol.Create(row - 1, col));
if (left.WallState.HasFlag(MazeCell.WallStates.Right) && current.WallState.HasFlag(MazeCell.WallStates.Left))
{
left.WallState ^= MazeCell.WallStates.Right;
}
if (above.WallState.HasFlag(MazeCell.WallStates.Bottom) && current.WallState.HasFlag(MazeCell.WallStates.Top))
{
above.WallState ^= MazeCell.WallStates.Bottom;
}
}
}
}
private bool ValidPos(PairRowCol p)
{
return(ValidPos(p.Row, p.Col));
}
private void MarkVisited(PairRowCol p)
{
MarkVisited(p.Row, p.Col);
}
public MazeCell GetCell(PairRowCol p) => GetCell(p.Row, p.Col);
private IEnumerable <PairRowCol> GetUnvisitedNeighbors(PairRowCol p)
{
return(GetNeighbors(p).Where(_p => !_map[_p.Row, _p.Col].Visited));
}
// Start is called before the first frame update
void Start()
{
Cursor.lockState = CursorLockMode.Confined;
_mg.Height = MazeRows;
_mg.Width = MazeColumns;
_mg.InvertY = true;
_mg.Generate();
var halfHeight = MazeRows / 2f;
var halfWidth = MazeColumns / 2f;
for (int row = 0; row < MazeRows; ++row)
{
for (int col = 0; col < MazeColumns; ++col)
{
Vector3 cellPos = new Vector3(col - halfWidth + 0.5f, 0, row - halfHeight + 0.5f);
var cell = _mg.GetCell(row, col);
if (cell.WallState.HasFlag(MazeGenerator.MazeCell.WallStates.Top))
{
GameObject g = Instantiate(_horizontalWallPrefab, _wallParent is null ? this.transform : _wallParent.transform);
g.name = $"Wall (N) ({row}, {col})";
g.transform.position = cellPos + new Vector3(0, g.transform.localScale.y / 2, +0.5f);
}
if (cell.WallState.HasFlag(MazeGenerator.MazeCell.WallStates.Bottom))
{
GameObject g = Instantiate(_horizontalWallPrefab, _wallParent is null ? this.transform : _wallParent.transform);
g.name = $"Wall (S) ({row}, {col})";
g.transform.position = cellPos + new Vector3(0, g.transform.localScale.y / 2, -0.5f);
}
if (cell.WallState.HasFlag(MazeGenerator.MazeCell.WallStates.Left))
{
GameObject g = Instantiate(_verticalWallPrefab, _wallParent is null ? this.transform : _wallParent.transform);
g.name = $"Wall (W) ({row}, {col})";
g.transform.position = cellPos + new Vector3(-0.5f, g.transform.localScale.y / 2, 0);
}
if (cell.WallState.HasFlag(MazeGenerator.MazeCell.WallStates.Right))
{
GameObject g = Instantiate(_verticalWallPrefab, _wallParent is null ? this.transform : _wallParent.transform);
g.name = $"Wall (E) ({row}, {col})";
g.transform.position = cellPos + new Vector3(+0.5f, g.transform.localScale.y / 2, 0);
}
}
}
{
var ballPos = GetRandomNonBlockedCell();
var ballLocalPos = CellToLocal(ballPos);
SpawnBall(CellToLocal(ballPos) + new Vector3(0, InitialBallHeight, 0));
PairRowCol winPos = PairRowCol.Create(0, 0);
var dist = (CellToLocal(winPos) - ballLocalPos).sqrMagnitude;
for (int row = 0; row < MazeRows; ++row)
{
for (int col = 0; col < MazeColumns; ++col)
{
PairRowCol pos = PairRowCol.Create(row, col);
if (_mg.GetCell(pos).WallState.HasFlag(MazeGenerator.MazeCell.WallStates.All))
{
continue;
}
var d = (CellToLocal(pos) - ballLocalPos).sqrMagnitude;
if (d > dist)
{
dist = d;
winPos = pos;
}
}
}
if (_debug)
{
SpawnWinningSpot(CellToLocal(PairRowCol.Create(ballPos.Row, ballPos.Col - 1)) + new Vector3(0, _winningSpotPrefab.transform.localScale.y / 2, 0));
}
else
{
SpawnWinningSpot(CellToLocal(winPos) + new Vector3(0, _winningSpotPrefab.transform.localScale.y / 2, 0));
}
}
}
Vector3 CellToLocal(PairRowCol p)
{
return(new Vector3(p.Col - MazeColumns / 2f + 0.5f, 0, p.Row - MazeRows / 2f + 0.5f));
}
