/// <summary>
/// Slide along the path steps until you hit something. Return path to point and if it ends attacking with the attack.
/// </summary>
private static List <position_t> Slide(ChessBoard board, Player p, position_t pos, position_t step)
{
List <position_t> moves = new List <position_t>();
for (int i = 1; i < 8; i++)
{
position_t moved = new position_t(pos.letter + i * step.letter, pos.number + i * step.number);
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
{
break;
}
if (board.Grid[moved.number][moved.letter].piece != Piece.NONE)
{
if (board.Grid[moved.number][moved.letter].player != p)
{
moves.Add(moved);
}
break;
}
moves.Add(moved);
}
return(moves);
}
/// <summary>
/// Checks to see if the king for a player is in check. This function
/// works by pretending the king is each of the different board pieces and seeing if it can attack
/// any of the same type of price from its current position.
/// </summary>
/// <param name="b">Board state</param>
/// <param name="king">the currnet player</param>
/// <returns>Is in check</returns>
public static bool isCheck(ChessBoard b, Player king)
{
if (b.Kings.Count == 0)
{
return(true);
}
position_t king_pos = b.Kings[king];
if (king_pos.number < 0 || king_pos.letter < 0)
{
return(true);
}
Piece[] pieces = { Piece.PAWN, Piece.ROOK, Piece.KNIGHT, Piece.BISHOP, Piece.QUEEN, Piece.KING };
ChessBoard tempBoard = new ChessBoard(b);
for (int i = 0; i < 6; i++)
{
tempBoard.Grid[king_pos.number][king_pos.letter] = new piece_t(pieces[i], king);
List <position_t> moves = getLegalMove(tempBoard, king_pos, false);
foreach (var move in moves)
{
if (b.Grid[move.number][move.letter].piece == pieces[i] &&
b.Grid[move.number][move.letter].player != king)
{
return(true);
}
}
}
return(false);
}
/// <summary>
/// Get any legal move from the current position on the provided board.
/// </summary>
/// <param name="board">The state of the game.</param>
/// <param name="pos">The piece/position to check for valid moves.</param>
/// <param name="verify_check">Whether or not to recurse and check if the current move puts you in check.</param>
/// <returns>A list of positions the piece can move to.</returns>
public static List <position_t> getLegalMove(ChessBoard board, position_t pos, bool verify_check = true)
{
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE)
{
return(new List <position_t>());
}
switch (p.piece)
{
case Piece.PAWN:
return(LegalMoveSet.Pawn(board, pos, verify_check));
case Piece.ROOK:
return(LegalMoveSet.Rook(board, pos, verify_check));
case Piece.KNIGHT:
return(LegalMoveSet.Knight(board, pos, verify_check));
case Piece.BISHOP:
return(LegalMoveSet.Bishop(board, pos, verify_check));
case Piece.QUEEN:
return(LegalMoveSet.Queen(board, pos, verify_check));
case Piece.KING:
return(LegalMoveSet.King(board, pos, verify_check));
default:
return(new List <position_t>());
}
}
private static List <position_t> Rook(ChessBoard board, position_t pos, bool verify_check = true)
{
List <position_t> moves = new List <position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE)
{
return(moves);
}
// slide along vert/hor for possible moves
moves.AddRange(Slide(board, p.player, pos, new position_t(1, 0)));
moves.AddRange(Slide(board, p.player, pos, new position_t(-1, 0)));
moves.AddRange(Slide(board, p.player, pos, new position_t(0, 1)));
moves.AddRange(Slide(board, p.player, pos, new position_t(0, -1)));
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return(moves);
}
private static List <position_t> Knight(ChessBoard board, position_t pos, bool verify_check = true)
{
List <position_t> moves = new List <position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE)
{
return(moves);
}
// collect all relative moves possible
List <position_t> relative = new List <position_t>();
relative.Add(new position_t(2, 1));
relative.Add(new position_t(2, -1));
relative.Add(new position_t(-2, 1));
relative.Add(new position_t(-2, -1));
relative.Add(new position_t(1, 2));
relative.Add(new position_t(-1, 2));
relative.Add(new position_t(1, -2));
relative.Add(new position_t(-1, -2));
// iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bounds check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
{
continue;
}
// if empty space or attacking
if (board.Grid[moved.number][moved.letter].piece == Piece.NONE ||
board.Grid[moved.number][moved.letter].player != p.player)
{
moves.Add(moved);
}
}
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return(moves);
}
private static bool allowCastle(ChessBoard board, Player player, position_t pos, bool isRight)
{
bool isValid = true;
int rookPos;
int kingDirection;
if (isRight)
{
rookPos = 7;
kingDirection = 1;
}
else
{
rookPos = 0;
kingDirection = -1;
}
//Check for valid right castling
// Is the peice at H,7 a rook owned by the player and has it moved
if (board.Grid[pos.number][rookPos].piece == Piece.ROOK &&
board.Grid[pos.number][rookPos].player == player && board.Grid[pos.number][rookPos].lastPosition.Equals(new position_t(-1, -1)))
{
// Check that the adjacent two squares are empty
for (int i = 0; i < 2; i++)
{
if (board.Grid[pos.number][pos.letter + (i + 1) * kingDirection].piece != Piece.NONE)
{
isValid = false;
break;
}
}
// Don't bother running secondary checks if the way isn't even clear
if (isValid)
{
for (int i = 0; i < 2; i++)
{
// Move kings postion over i squares to check if king is passing over an attackable
// square
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, new position_t(pos.letter + (i + 1) * kingDirection, pos.number)));
// Attackable square is in between king and rook so
// its not possible to castle to the right rook
if (isCheck(b2, player))
{
isValid = false;
break;
}
}
}
}
else
{
isValid = false;
}
return(isValid);
}
public void SetPiece(Piece piece, Player player, int letter, int number)
{
// set grid values
Grid[number][letter].piece = piece;
Grid[number][letter].player = player;
// add piece to list
Pieces[player].Add(new position_t(letter, number));
// update king position
if (piece == Piece.KING)
{
Kings[player] = new position_t(letter, number);
}
}
public void SetRandomPlacement()
{
//Add the pieces via using the SetPiece() method
//Check for placement, then add:
Random r = new Random();
int letter = r.Next(0, 8), number = 0;
//Pawns
for (int i = 0; i < 8; i++)
{
SetPiece(Piece.PAWN, Player.WHITE, i, 1);
SetPiece(Piece.PAWN, Player.BLACK, i, 6);
}
//Kings
AssignPiece(Piece.KING, out letter, out number);
Kings[Player.WHITE] = new position_t(letter, number);
Kings[Player.BLACK] = new position_t(letter, Mirror(number));
//Rooks
AssignPiece(Piece.ROOK, out letter, out number);
AssignPiece(Piece.ROOK, out letter, out number);
//Bishops
AssignPiece(Piece.BISHOP, out letter, out number);
BishopPos = new position_t(letter, number);
//Somehow.. get where the bishop was placed.
AssignPiece(Piece.BISHOP, out letter, out number);
//Queens
AssignPiece(Piece.QUEEN, out letter, out number);
//Knights
AssignPiece(Piece.KNIGHT, out letter, out number);
AssignPiece(Piece.KNIGHT, out letter, out number);
}
private static List <position_t> Pawn(ChessBoard board, position_t pos, bool verify_check = true)
{
List <position_t> moves = new List <position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE)
{
return(moves);
}
// gather relative moves
List <position_t> relative = new List <position_t>();
relative.Add(new position_t(-1, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(0, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(0, 2 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(1, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
// iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bounds check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
{
continue;
}
// double forward move
if (moved.letter == pos.letter && board.Grid[moved.number][moved.letter].piece == Piece.NONE && Math.Abs(moved.number - pos.number) == 2)
{
// check the first step
int step = -((moved.number - pos.number) / (Math.Abs(moved.number - pos.number)));
bool hasnt_moved = pos.number == ((p.player == Player.BLACK) ? 6 : 1);
if (board.Grid[moved.number + step][moved.letter].piece == Piece.NONE && hasnt_moved)
{
moves.Add(moved);
}
}
// if it's not blocked we can move forward
else if (moved.letter == pos.letter && board.Grid[moved.number][moved.letter].piece == Piece.NONE)
{
moves.Add(moved);
}
// angled attack
else if (moved.letter != pos.letter && board.Grid[moved.number][moved.letter].piece != Piece.NONE && board.Grid[moved.number][moved.letter].player != p.player)
{
moves.Add(moved);
}
// en passant
else if (isEnPassant(board, new move_t(pos, moved)))
{
moves.Add(moved);
}
}
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return(moves);
}
private static List <position_t> King(ChessBoard board, position_t pos, bool verify_check = true)
{
List <position_t> moves = new List <position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE)
{
return(moves);
}
// collect all relative moves possible
List <position_t> relative = new List <position_t>();
relative.Add(new position_t(-1, 1));
relative.Add(new position_t(0, 1));
relative.Add(new position_t(1, 1));
relative.Add(new position_t(-1, 0));
relative.Add(new position_t(1, 0));
relative.Add(new position_t(-1, -1));
relative.Add(new position_t(0, -1));
relative.Add(new position_t(1, -1));
// Iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bound check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
{
continue;
}
// if it's not blocked we can move
if (board.Grid[moved.number][moved.letter].piece == Piece.NONE || board.Grid[moved.number][moved.letter].player != p.player)
{
if (verify_check) // make sure we don't put ourselves in check
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moved));
if (!isCheck(b2, p.player))
{
moves.Add(moved);
}
}
else
{
moves.Add(moved);
}
}
}
// Castling
/* A king can only castle if:
* king has not moved
* rook has not moved
* king is not in check
* king does not end up in check
* king does not pass through any other peieces
* king does not pass through any squares under attack
* king knows secret handshake
*/
if (verify_check)
{
if (!isCheck(board, p.player) &&
p.lastPosition.Equals(new position_t(-1, -1)))
{
bool castleRight = allowCastle(board, p.player, pos, true);
bool castleLeft = allowCastle(board, p.player, pos, false);
if (castleRight)
{
moves.Add(new position_t(6, pos.number));
}
if (castleLeft)
{
moves.Add(new position_t(2, pos.number));
}
}
}
return(moves);
}
/// <summary>
/// Slide along the path steps until you hit something. Return path to point and if it ends attacking with the attack.
/// </summary>
private static List<position_t> Slide(ChessBoard board, Player p, position_t pos, position_t step)
{
List<position_t> moves = new List<position_t>();
for (int i = 1; i < 8; i++)
{
position_t moved = new position_t(pos.letter + i * step.letter, pos.number + i * step.number);
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
break;
if (board.Grid[moved.number][moved.letter].piece != Piece.NONE)
{
if (board.Grid[moved.number][moved.letter].player != p)
moves.Add(moved);
break;
}
moves.Add(moved);
}
return moves;
}
public List<position_t> Select(position_t pos)
{
// has previously selected something
if (this.Board.Grid[this.Selection.number][this.Selection.letter].piece != Piece.NONE
&& this.Turn == this.Board.Grid[this.Selection.number][this.Selection.letter].player
&& (this.m_nPlayers == 2
|| this.Turn == Player.WHITE))
{
// get previous selections moves and determine if we chose a legal one by clicking
List<position_t> moves = LegalMoveSet.getLegalMove(this.Board, this.Selection);
foreach (position_t move in moves)
{
if (move.Equals(pos))
{
// we selected a legal move so update the board
MakeMove(new move_t(this.Selection, pos));
// If piece that was just moved is a king and it moved anyhthing other than 1 square, it was
// a castling move, so we need to move the rook
if (this.Board.Grid[pos.number][pos.letter].piece == Piece.KING && Math.Abs(pos.letter - this.Selection.letter) == 2)
{
int row = (this.Turn == Player.WHITE) ? 0 : 7;
// Left rook
if (pos.letter < 4)
{
LegalMoveSet.move(this.Board, new move_t(new position_t(0, row), new position_t(3, row)));
}
// right rook
else
{
LegalMoveSet.move(this.Board, new move_t(new position_t(7, row), new position_t(5, row)));
}
}
// finish move
switchPlayer();
if (detectCheckmate()) return new List<position_t>();
if (this.m_nPlayers == 1) // start ai
{
new Thread(AISelect).Start(); // thread turn
}
return new List<position_t>();
}
}
}
// first click, let's show possible moves
if (this.Board.Grid[pos.number][pos.letter].player == this.Turn && (this.m_nPlayers == 2 || this.Turn == Player.WHITE))
{
List<position_t> moves = LegalMoveSet.getLegalMove(this.Board, pos);
this.Selection = pos;
return moves;
}
// reset
this.Selection = new position_t();
return new List<position_t>();
}
public void SetPiece(Piece piece, Player player, int letter, int number)
{
// set grid values
Grid[number][letter].piece = piece;
Grid[number][letter].player = player;
// add piece to list
Pieces[player].Add(new position_t(letter, number));
// update king position
if (piece == Piece.KING)
{
Kings[player] = new position_t(letter, number);
}
}
private static List<position_t> Pawn(ChessBoard board, position_t pos, bool verify_check = true)
{
List<position_t> moves = new List<position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE) return moves;
// gather relative moves
List<position_t> relative = new List<position_t>();
relative.Add(new position_t(-1, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(0, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(0, 2 * ((p.player == Player.BLACK) ? -1 : 1)));
relative.Add(new position_t(1, 1 * ((p.player == Player.BLACK) ? -1 : 1)));
// iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bounds check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
continue;
// double forward move
if (moved.letter == pos.letter && board.Grid[moved.number][moved.letter].piece == Piece.NONE && Math.Abs(moved.number - pos.number) == 2)
{
// check the first step
int step = -((moved.number - pos.number) / (Math.Abs(moved.number - pos.number)));
bool hasnt_moved = pos.number == ((p.player == Player.BLACK) ? 6 : 1);
if (board.Grid[moved.number + step][moved.letter].piece == Piece.NONE && hasnt_moved)
{
moves.Add(moved);
}
}
// if it's not blocked we can move forward
else if (moved.letter == pos.letter && board.Grid[moved.number][moved.letter].piece == Piece.NONE)
{
moves.Add(moved);
}
// angled attack
else if (moved.letter != pos.letter && board.Grid[moved.number][moved.letter].piece != Piece.NONE && board.Grid[moved.number][moved.letter].player != p.player)
{
moves.Add(moved);
}
// en passant
else if(isEnPassant(board, new move_t(pos,moved)))
{
moves.Add(moved);
}
}
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return moves;
}
private static List<position_t> Rook(ChessBoard board, position_t pos, bool verify_check = true)
{
List<position_t> moves = new List<position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE) return moves;
// slide along vert/hor for possible moves
moves.AddRange(Slide(board, p.player, pos, new position_t(1, 0)));
moves.AddRange(Slide(board, p.player, pos, new position_t(-1, 0)));
moves.AddRange(Slide(board, p.player, pos, new position_t(0, 1)));
moves.AddRange(Slide(board, p.player, pos, new position_t(0, -1)));
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return moves;
}
private static List<position_t> Knight(ChessBoard board, position_t pos, bool verify_check = true)
{
List<position_t> moves = new List<position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE) return moves;
// collect all relative moves possible
List<position_t> relative = new List<position_t>();
relative.Add(new position_t(2, 1));
relative.Add(new position_t(2, -1));
relative.Add(new position_t(-2, 1));
relative.Add(new position_t(-2, -1));
relative.Add(new position_t(1, 2));
relative.Add(new position_t(-1, 2));
relative.Add(new position_t(1, -2));
relative.Add(new position_t(-1, -2));
// iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bounds check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
continue;
// if empty space or attacking
if (board.Grid[moved.number][moved.letter].piece == Piece.NONE ||
board.Grid[moved.number][moved.letter].player != p.player)
moves.Add(moved);
}
if (verify_check)// make sure each move doesn't put us in check
{
for (int i = moves.Count - 1; i >= 0; i--)
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moves[i]));
if (isCheck(b2, p.player))
{
moves.RemoveAt(i);
}
}
}
return moves;
}
private static bool allowCastle(ChessBoard board, Player player, position_t pos, bool isRight)
{
bool isValid = true;
int rookPos;
int kingDirection;
if (isRight)
{
rookPos = 7;
kingDirection = 1;
}
else
{
rookPos = 0;
kingDirection = -1;
}
//Check for valid right castling
// Is the peice at H,7 a rook owned by the player and has it moved
if (board.Grid[pos.number][rookPos].piece == Piece.ROOK &&
board.Grid[pos.number][rookPos].player == player && board.Grid[pos.number][rookPos].lastPosition.Equals(new position_t(-1,-1)))
{
// Check that the adjacent two squares are empty
for (int i = 0; i < 2; i++)
{
if (board.Grid[pos.number][pos.letter + (i + 1) * kingDirection].piece != Piece.NONE)
{
isValid = false;
break;
}
}
// Don't bother running secondary checks if the way isn't even clear
if (isValid)
{
for (int i = 0; i < 2; i++)
{
// Move kings postion over i squares to check if king is passing over an attackable
// square
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, new position_t(pos.letter + (i + 1) * kingDirection, pos.number)));
// Attackable square is in between king and rook so
// its not possible to castle to the right rook
if (isCheck(b2, player))
{
isValid = false;
break;
}
}
}
}
else
{
isValid = false;
}
return isValid;
}
private static List<position_t> King(ChessBoard board, position_t pos, bool verify_check = true)
{
List<position_t> moves = new List<position_t>();
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE) return moves;
// collect all relative moves possible
List<position_t> relative = new List<position_t>();
relative.Add(new position_t(-1, 1));
relative.Add(new position_t(0, 1));
relative.Add(new position_t(1, 1));
relative.Add(new position_t(-1, 0));
relative.Add(new position_t(1, 0));
relative.Add(new position_t(-1, -1));
relative.Add(new position_t(0, -1));
relative.Add(new position_t(1, -1));
// Iterate moves
foreach (position_t move in relative)
{
position_t moved = new position_t(move.letter + pos.letter, move.number + pos.number);
// bound check
if (moved.letter < 0 || moved.letter > 7 || moved.number < 0 || moved.number > 7)
continue;
// if it's not blocked we can move
if (board.Grid[moved.number][moved.letter].piece == Piece.NONE || board.Grid[moved.number][moved.letter].player != p.player)
{
if (verify_check) // make sure we don't put ourselves in check
{
ChessBoard b2 = LegalMoveSet.move(board, new move_t(pos, moved));
if(!isCheck(b2, p.player))
{
moves.Add(moved);
}
}
else
{
moves.Add(moved);
}
}
}
// Castling
/* A king can only castle if:
* king has not moved
* rook has not moved
* king is not in check
* king does not end up in check
* king does not pass through any other peieces
* king does not pass through any squares under attack
* king knows secret handshake
*/
if (verify_check)
{
if (!isCheck(board, p.player)
&& p.lastPosition.Equals(new position_t(-1,-1)))
{
bool castleRight = allowCastle(board, p.player, pos, true);
bool castleLeft = allowCastle(board, p.player, pos, false);
if (castleRight)
{
moves.Add(new position_t(6, pos.number));
}
if (castleLeft)
{
moves.Add(new position_t(2, pos.number));
}
}
}
return moves;
}
public List <position_t> Select(position_t pos)
{
// has previously selected something
if (this.Board.Grid[this.Selection.number][this.Selection.letter].piece != Piece.NONE &&
this.Turn == this.Board.Grid[this.Selection.number][this.Selection.letter].player &&
(this.m_nPlayers == 2 ||
this.Turn == Player.WHITE))
{
// get previous selections moves and determine if we chose a legal one by clicking
List <position_t> moves = LegalMoveSet.getLegalMove(this.Board, this.Selection);
foreach (position_t move in moves)
{
if (move.Equals(pos))
{
// we selected a legal move so update the board
MakeMove(new move_t(this.Selection, pos));
// If piece that was just moved is a king and it moved anyhthing other than 1 square, it was
// a castling move, so we need to move the rook
if (this.Board.Grid[pos.number][pos.letter].piece == Piece.KING && Math.Abs(pos.letter - this.Selection.letter) == 2)
{
int row = (this.Turn == Player.WHITE) ? 0 : 7;
// Left rook
if (pos.letter < 4)
{
LegalMoveSet.move(this.Board, new move_t(new position_t(0, row), new position_t(3, row)));
}
// right rook
else
{
LegalMoveSet.move(this.Board, new move_t(new position_t(7, row), new position_t(5, row)));
}
}
// finish move
switchPlayer();
if (detectCheckmate())
{
return(new List <position_t>());
}
if (this.m_nPlayers == 1) // start ai
{
new Thread(AISelect).Start(); // thread turn
}
return(new List <position_t>());
}
}
}
// first click, let's show possible moves
if (this.Board.Grid[pos.number][pos.letter].player == this.Turn && (this.m_nPlayers == 2 || this.Turn == Player.WHITE))
{
List <position_t> moves = LegalMoveSet.getLegalMove(this.Board, pos);
this.Selection = pos;
return(moves);
}
// reset
this.Selection = new position_t();
return(new List <position_t>());
}
/// <summary>
/// Get any legal move from the current position on the provided board.
/// </summary>
/// <param name="board">The state of the game.</param>
/// <param name="pos">The piece/position to check for valid moves.</param>
/// <param name="verify_check">Whether or not to recurse and check if the current move puts you in check.</param>
/// <returns>A list of positions the piece can move to.</returns>
public static List<position_t> getLegalMove(ChessBoard board, position_t pos, bool verify_check = true)
{
piece_t p = board.Grid[pos.number][pos.letter];
if (p.piece == Piece.NONE) return new List<position_t>();
switch (p.piece)
{
case Piece.PAWN:
return LegalMoveSet.Pawn(board, pos, verify_check);
case Piece.ROOK:
return LegalMoveSet.Rook(board, pos, verify_check);
case Piece.KNIGHT:
return LegalMoveSet.Knight(board, pos, verify_check);
case Piece.BISHOP:
return LegalMoveSet.Bishop(board, pos, verify_check);
case Piece.QUEEN:
return LegalMoveSet.Queen(board, pos, verify_check);
case Piece.KING:
return LegalMoveSet.King(board, pos, verify_check);
default:
return new List<position_t>();
}
}