/// <summary>
/// Constructs a new TicTacToe game using the specified player's pieces.
///
/// </summary>
/// <param name="player1Piece">Player one's piece</param>
/// <param name="player2Piece">Player two's piece</param>
public TicTacToeGame(Board.Pieces player1Piece, Board.Pieces player2Piece)
{
this.player1Piece = player1Piece;
this.player2Piece = player2Piece;
board = new Board();
moves = new Stack <TicTacToeMove>();
}
/// <summary>
/// Constructs a new TicTacToe game using the specified player's pieces.
///
/// </summary>
/// <param name="player1Piece">Player one's piece</param>
/// <param name="player2Piece">Player two's piece</param>
public TicTacToeGame(Board.Pieces player1Piece, Board.Pieces player2Piece)
{
this.player1Piece = player1Piece;
this.player2Piece = player2Piece;
board = new Board();
moves = new Stack<TicTacToeMove>();
}
/// <summary>
/// Constructs a new Node
/// </summary>
/// <param name="b">The board that the Node will use to evaluate itself and generate its children</param>
/// <param name="parent">The parent of this node</param>
/// <param name="move">The move from the parent's board that generated this node's board</param>
public Node(Board b, Node parent, TicTacToeMove move)
{
this.board = b;
this.parent = parent;
this.move = move;
if (parent != null)
myPiece = Board.GetOponentPiece(parent.MyPiece);
children = new List<Node>();
}
/// <summary>
/// Constructs a new Node
/// </summary>
/// <param name="b">The board that the Node will use to evaluate itself and generate its children</param>
/// <param name="parent">The parent of this node</param>
/// <param name="move">The move from the parent's board that generated this node's board</param>
public Node(Board b, Node parent, TicTacToeMove move)
{
this.board = b;
this.parent = parent;
this.move = move;
if (parent != null)
{
myPiece = Board.GetOponentPiece(parent.MyPiece);
}
children = new List <Node>();
}
// draws each piece on the board onto the panel
private void DrawPieces(Graphics g)
{
for (int i = 0; i < game.Rows * game.Columns; i++)
{
Board.Pieces piece = game.GameBoard.GetPieceAtPosition(i);
if (piece == Board.Pieces.X || piece == Board.Pieces.O)
{
DrawPiece(piece, g, i);
}
}
}
// returns the Player who has the specified piece
protected TicTacToeGame.Players GetPlayerWhoHasPiece(Board.Pieces piece)
{
if (piece == player1Piece)
{
return(Players.Player1);
}
else
{
return(Players.Player2);
}
}
/// <summary>
/// Returns the piece representing the opponent
/// </summary>
/// <param name="yourPiece">The piece representing the player</param>
/// <returns></returns>
public static Board.Pieces GetOponentPiece(Board.Pieces yourPiece)
{
if (yourPiece == Board.Pieces.X)
{
return(Board.Pieces.O);
}
else if (yourPiece == Board.Pieces.O)
{
return(Board.Pieces.X);
}
else
{
throw new Exception("Invalid Piece!");
}
}
/// <summary>
/// Draws the specified piece on the board in the designated position.
/// Position 0 is the upper left square on the board and position 8 is the lower right
/// corner square on the board
/// </summary>
/// <param name="p">The piece we wish to draw</param>
/// <param name="g">The graphics object we are drawing on</param>
/// <param name="position">The position on the board to draw at</param>
private void DrawPiece(Board.Pieces p, Graphics g, int position)
{
float pixelsPerRow = ticTacToePanel.Width / game.Rows;
float pixelsPerColumn = ticTacToePanel.Height / game.Columns;
PointF point = GetPieceDrawingCoordsFromPosition(position);
Font f = new Font("Arial", 40);
if (p == Board.Pieces.X)
{
g.DrawString("X", f, Brushes.Blue, point);
}
else if (p == Board.Pieces.O)
{
g.DrawString("O", f, Brushes.Red, point);
}
}
/// <summary>
/// Evaluates the favorability of the current board configuration for maxPiece. Higher values
/// indicate better configuration for maxPiece
/// </summary>
/// <param name="b">the game board to evaluate</param>
/// <param name="maxPiece">the piece representing MAX</param>
/// <returns></returns>
public double Evaluate(Board b, Board.Pieces maxPiece)
{
functionCalls++;
if (b.HasWinner())
{
if (b.WinningPiece == maxPiece)
{
return(double.MaxValue);
}
else
{
return(double.MinValue);
}
}
double maxValue = EvaluatePiece(b, maxPiece);
double minValue = EvaluatePiece(b, Board.GetOponentPiece(maxPiece));
return(maxValue - minValue);
}
// over all rows sums the number of pieces in the row if
// the specified piece can still win in that row i.e. the row
// does not contain an opponent's piece
private double EvaluateColumns(Board b, Board.Pieces p)
{
int cols = b.Columns;
int rows = b.Rows;
double score = 0.0;
int count;
// check the rows
for (int j = 0; j < b.Columns; j++)
{
count = 0;
bool rowClean = true;
for (int i = 0; i < b.Columns; i++)
{
Board.Pieces boardPiece = b.GetPieceAtPoint(i, j);
if (boardPiece == p)
{
count++;
}
else if (boardPiece == Board.GetOponentPiece(p))
{
rowClean = false;
break;
}
}
// if we get here then the row is clean (an open row)
if (rowClean && count != 0)
{
score += count; //Math.Pow(count, count);
}
}
return(score);
}
// over both diagonals sums the number of pieces in the diagonal if
// the specified piece can still win in that diagonal i.e. the diagonal
// does not contain an opponent's piece
private double EvaluateDiagonals(Board b, Board.Pieces p)
{
// go down and to the right diagonal first
int count = 0;
bool diagonalClean = true;
double score = 0.0;
for (int i = 0; i < b.Columns; i++)
{
Board.Pieces boardPiece = b.GetPieceAtPoint(i, i);
if (boardPiece == p)
{
count++;
}
if (boardPiece == Board.GetOponentPiece(p))
{
diagonalClean = false;
break;
}
}
if (diagonalClean && count > 0)
{
score += count;// Math.Pow(count, count);
}
// now try the other way
int row = 0;
int col = 2;
count = 0;
diagonalClean = true;
while (row < b.Rows && col >= 0)
{
Board.Pieces boardPiece = b.GetPieceAtPoint(row, col);
if (boardPiece == p)
{
count++;
}
if (boardPiece == Board.GetOponentPiece(p))
{
diagonalClean = false;
break;
}
row++;
col--;
}
if (count > 0 && diagonalClean)
{
score += count;
}
return(score);
}
// sums up all the possible ways to win for the specified board piece
private double EvaluatePiece(Board b, Board.Pieces p)
{
return(EvaluateRows(b, p) + EvaluateColumns(b, p) + EvaluateDiagonals(b, p));
}
/// <summary>
/// Constructs a TicTacToeMove
/// </summary>
/// <param name="position">The position to move to</param>
/// <param name="piece">The piece that is moving</param>
public TicTacToeMove(int position, Board.Pieces piece)
{
this.Position = position;
this.Piece = piece;
}
public Player(string name, Board.Pieces p)
{
this.Name = name;
this.PlayerPiece = p;
}
public HumanPlayer(string name, Board.Pieces p, TicTacToeForm tttf)
: base(name, p)
{
this.ticTacToeForm = tttf;
}
/// <summary>
/// Constructs a new computer player
/// </summary>
/// <param name="name">The name of the player</param>
/// <param name="p">The piece the player is using</param>
/// <param name="searchDepth">The depth to search for moves in the game tree.</param>
public ComputerPlayer(string name, Board.Pieces p, int searchDepth) : base(name, p)
{
this.SearchDepth = searchDepth;
}
/// <summary>
/// Constructs a new computer player. The DEFAULT_SEARCH_DEPTH is used
/// </summary>
/// <param name="name">The name of the player</param>
/// <param name="p">The piece this player is using in the came</param>
public ComputerPlayer(string name, Board.Pieces p) : this(name,
p, DEFAULT_SEARCH_DEPTH)
{
}
