public static void AddQuietMove(Board.Board board, int move, MoveList list)
{
Debug.Assert(Validators.SqOnBoard(MoveOperations.FromSq(move)));
Debug.Assert(Validators.SqOnBoard(MoveOperations.ToSq(move)));
list.Moves[list.Count].Move = move;
/* Captures generate 1.000.000 or higher score, therefore we have to
* score the move just below this, to ensure this is second highest priority for search
* after capture moves.
*/
if (board.SearchKillers[0, board.Ply] == move)
{
list.Moves[list.Count].Score = 900000;
}
else if (board.SearchKillers[1, board.Ply] == move)
{
list.Moves[list.Count].Score = 800000;
}
else
{
int from = MoveOperations.FromSq(move);
int to = MoveOperations.ToSq(move);
list.Moves[list.Count].Score = board.SearchHistory[board[from], to];
}
list.Count++;
}
// Capture move
private static void AddWhitePawnCapMove(Board.Board board, int from, int to, int capt,
MoveList list)
{
Debug.Assert(Validators.PieceValidEmpty(capt), String.Format("Invalid capture square {0}", capt));
Debug.Assert(Validators.SqOnBoard(from), String.Format("Invalid from square {0}", from));
Debug.Assert(Validators.SqOnBoard(to), String.Format("Invalid to square {0}", to));
// If White pawn promotion.
if (Conversion.getRanksBrd(from) == (int)Rank.RANK_7)
{
MoveGen.AddCaptureMove(board,
MoveOperations.CreateMove(from, to, capt, (int)Piece.wQ, 0),
list);
MoveGen.AddCaptureMove(board,
MoveOperations.CreateMove(from, to, capt, (int)Piece.wR, 0),
list);
MoveGen.AddCaptureMove(board,
MoveOperations.CreateMove(from, to, capt, (int)Piece.wB, 0),
list);
MoveGen.AddCaptureMove(board,
MoveOperations.CreateMove(from, to, capt, (int)Piece.wN, 0),
list);
}
else
{
MoveGen.AddCaptureMove(board,
MoveOperations.CreateMove(from, to, capt, (int)Piece.EMPTY, 0), list);
}
}
public static void AddEnPassantMove(Board.Board board, int move, MoveList list)
{
Debug.Assert(Validators.SqOnBoard(MoveOperations.FromSq(move)));
Debug.Assert(Validators.SqOnBoard(MoveOperations.ToSq(move)));
list.Moves[list.Count].Move = move;
list.Moves[list.Count].Score = 105 + 1000000;
list.Count++;
}
public static void AddCaptureMove(Board.Board board, int move, MoveList list)
{
Debug.Assert(Validators.SqOnBoard(MoveOperations.FromSq(move)));
Debug.Assert(Validators.SqOnBoard(MoveOperations.ToSq(move)));
Debug.Assert(Validators.PieceValidEmpty(MoveOperations.Captured(move)), String.Format("Invalid piece {0} was captured", MoveOperations.Captured(move)));
var captured = MoveOperations.Captured(move);
var attacker = board[MoveOperations.FromSq(move)];
list.Moves[list.Count].Move = move;
list.Moves[list.Count].Score = MvvLva.Scores[captured, attacker] + 1000000;
list.Count++;
}
public static void TakeMove(Board.Board board)
{
Debug.Assert(BoardOperations.CheckBoard(board));
// Decrement the plys.
board.HistoryPly--;
board.Ply--;
int move = board.History[board.HistoryPly].Move;
int from = MoveOperations.FromSq(move);
int to = MoveOperations.ToSq(move);
Debug.Assert(Validators.SqOnBoard(from), String.Format("Invalid From Square {0}", Io.SqToString(from)));
Debug.Assert(Validators.SqOnBoard(to), String.Format("Invalid To Square {0}", Io.SqToString(to)));
// If there is an EnPas square, hash it out.
if (board.EnPas != (int)Square.NO_SQ)
{
HashEnPas(board);
}
HashCastle(board);
// Reverse relevant board structures.
board.CastlePerm = board.History[board.HistoryPly].CastlePerm;
board.FiftyMoves = board.History[board.HistoryPly].FiftyMoves;
board.EnPas = board.History[board.HistoryPly].EnPas;
// If the previous move have an EnPas square set, we need to hash it back in
if (board.EnPas != (int)Square.NO_SQ)
{
HashEnPas(board);
}
// Hash the castling back incase it's changed.
HashCastle(board);
// Change the side to move back.
board.Side ^= 1;
HashSide(board);
if ((move & MoveOperations.MoveFlagEnPas) != 0)
{
if (board.Side == (int)Colour.WHITE) // If EnPas move we need to add the pawn
{
AddPiece(to - 10, board, (int)Piece.bP);
}
else // Else black
{
AddPiece(to + 10, board, (int)Piece.wP);
}
}
else if ((move & MoveOperations.MoveFlagCastle) != 0)
{
// If castle we need to move the rook.
switch (to)
{
case (int)Square.C1:
MovePiece((int)Square.D1, (int)Square.A1, board); break;
case (int)Square.C8:
MovePiece((int)Square.D8, (int)Square.A8, board); break;
case (int)Square.G1:
MovePiece((int)Square.F1, (int)Square.H1, board); break;
case (int)Square.G8:
MovePiece((int)Square.F8, (int)Square.H8, board); break;
default:
throw new Exception(
"The move is a castling move, but the to square doesn't match any eligible moves");
}
}
// Move the piece back to the original square.
MovePiece(to, from, board);
if (Data.IsPieceKing(board[from]))
{
board.KingSq[board.Side] = from;
}
int captured = MoveOperations.Captured(move);
if (captured != (int)Piece.EMPTY)
{
Debug.Assert(Validators.PieceValid(captured), "Invalid piece captured");
AddPiece(to, board, captured);
}
int promotedPce = MoveOperations.Promoted(move);
if (promotedPce != (int)Piece.EMPTY) // If there is a promoted piece
// A piece cannot be promoted to a pawn.
{
Debug.Assert((Validators.PieceValid(promotedPce) || !Data.IsPiecePawn(promotedPce)), String.Format("Promoted piece {0} is invalid. PieceValid returned {1}, and IsPiecePawn returned {2}", (Piece)promotedPce, Validators.PieceValid(promotedPce), Data.IsPiecePawn(promotedPce)));
ClearPiece(from, board);
AddPiece(from, board, ((Data.PIECE_COLOURS[promotedPce] == Colour.WHITE) ? (int)Piece.wP : (int)Piece.bP));
}
Debug.Assert(BoardOperations.CheckBoard(board));
}
// Possibly not static
// Returns true if legal move, or false otherwise
/// <summary>
/// Makes the input move on the board, if the move is legal.
/// If illegal, nothing happens and the method returns false.
/// </summary>
/// <param name="board"> The board to make the move on </param>
/// <param name="move"> The move to perform </param>
public static bool Make_Move(Board.Board board, int move)
{
Debug.Assert(BoardOperations.CheckBoard(board), "The CheckBoard method returned false.");
int from = MoveOperations.FromSq(move);
int to = MoveOperations.ToSq(move);
int side = board.Side;
Debug.Assert(Validators.SqOnBoard(from), String.Format("Invalid From Square {0}", Io.SqToString(from)));
Debug.Assert(Validators.SqOnBoard(to), String.Format("Invalid To Square {0}", Io.SqToString(to)));
Debug.Assert(Validators.SideValid(side), String.Format("Invalid Side with integer value {0}", side));
Debug.Assert(Validators.PieceValid(board[from]), String.Format("Invalid From Square {0}", Io.SqToString(from)));
board.History[board.HistoryPly].PosKey = board.PosKey;
// Now we check for special moves.
if ((move & MoveOperations.MoveFlagEnPas) != 0)
{
if (side == (int)Colour.WHITE) // If EnPas move we need to kill the pawn
{
ClearPiece(to - 10, board);
}
else // Else black
{
ClearPiece(to + 10, board);
}
}
else if ((move & MoveOperations.MoveFlagCastle) != 0)
{
// If castle we need to move the rook.
switch (to)
{
case (int)Square.C1:
MovePiece((int)Square.A1, (int)Square.D1, board); break;
case (int)Square.C8:
MovePiece((int)Square.A8, (int)Square.D8, board); break;
case (int)Square.G1:
MovePiece((int)Square.H1, (int)Square.F1, board); break;
case (int)Square.G8:
MovePiece((int)Square.H8, (int)Square.F8, board); break;
default:
throw new Exception(
"The move is a castling move, but the to square doesn't match any eligible moves");
}
}
if (board.EnPas != (int)Square.NO_SQ)
{
MakeMove.HashEnPas(board);
}
MakeMove.HashCastle(board); // POSSIBLE ERROR, MAYBE IT SHOULD BE IN IF STATEMENT ABOVE.
// Store information in history array.
board.History[board.HistoryPly].Move = move;
board.History[board.HistoryPly].EnPas = board.EnPas;
board.History[board.HistoryPly].CastlePerm = board.CastlePerm;
board.History[board.HistoryPly].FiftyMoves = board.FiftyMoves;
// Adjust castle permissions if rook or king has moved.
board.CastlePerm &= MakeMove.castlePerm[from];
board.CastlePerm &= MakeMove.castlePerm[to];
board.EnPas = (int)Square.NO_SQ;
HashCastle(board);
int captured = MoveOperations.Captured(move);
board.FiftyMoves++;
// If there is a piece captured
if (captured != (int)Piece.EMPTY)
{
// Test if the piece is valid.
Debug.Assert(Validators.PieceValid(captured), String.Format("Invalid piece ID integer {0}", captured));
ClearPiece(to, board);
board.FiftyMoves = 0; // reset 50moves, cuz a piece has been captured.
}
board.HistoryPly++;
board.Ply++;
if (Data.IsPiecePawn(board[from]))
{
board.FiftyMoves = 0; // Reset 50moves, cuz a pawn has moved.
if ((move & MoveOperations.MoveFlagPawnStart) != 0)
{
if (side == (int)Colour.WHITE)
{
board.EnPas = from + 10;
Debug.Assert(Conversion.getRanksBrd(board.EnPas) == (int)Rank.RANK_3, String.Format("Invalid board state: the enPas square {0} is wrong", Io.SqToString(board.EnPas)));
}
else
{
board.EnPas = from - 10;
Debug.Assert(Conversion.getRanksBrd(board.EnPas) == (int)Rank.RANK_6, String.Format("Invalid board state: the enPas square {0} is wrong", Io.SqToString(board.EnPas)));
}
HashEnPas(board);
}
}
MovePiece(from, to, board);
int promotedPce = MoveOperations.Promoted(move);
if (promotedPce != (int)Piece.EMPTY) // If there is a promoted piece
// A piece cannot be promoted to a pawn.
{
Debug.Assert(Validators.PieceValid(promotedPce) && !Data.IsPiecePawn(promotedPce), String.Format("Promoted piece {0} is invalid", (Piece)promotedPce));
ClearPiece(to, board);
AddPiece(to, board, promotedPce);
}
if (Data.IsPieceKing(board[to]))
{
// If piece is king set the KingSQ
board.KingSq[side] = to;
}
// Exclusive or, changes the side from white to black or black to white.
board.Side ^= 1;
HashSide(board);
Debug.Assert(BoardOperations.CheckBoard(board));
// Make sure that the new king square isn't attacked.
if (Attack.IsSqAttacked(board.KingSq[side], board.Side, board))
{
TakeMove(board);
return(false);
}
return(true);
}
/// <summary>
/// Generates all available moves for the current position on the board in the parameter MoveList.
/// If the onlyCaptures parameter is true, it will only generate capture moves.
/// </summary>
/// <param name="board"> The current board position </param>
/// <param name="list"> The MoveList to parse the available moves to. </param>
/// <param name="onlyCaptures"> True if only generating for captures. </param>
public static void GenerateAllMoves(Board.Board board, MoveList list, bool onlyCaptures)
{
Debug.Assert(BoardOperations.CheckBoard(board));
list.Count = 0;
var side = (Colour)board.Side;
var piece = side == Colour.WHITE ? (int)Piece.wP : (int)Piece.bP;
for (var pceNum = 0; pceNum < board.PceNum[piece]; ++pceNum)
{
var sq = board.PList[piece, pceNum];
Debug.Assert(Validators.IsSq(sq), String.Format("Sq {0} is invalid", sq));
var leftCaptureSq = side == Colour.WHITE ? sq + 9 : sq - 9;
var rightCaptureSq = side == Colour.WHITE ? sq + 11 : sq - 11;
if (!onlyCaptures)
{
var sqInfront = side == Colour.WHITE ? sq + 10 : sq - 10;
if (board[sqInfront] == (int)Piece.EMPTY && Validators.SqOnBoard(sqInfront))
{
if (side == Colour.WHITE)
{
MoveGen.AddWhitePawnMove(board, sq, sqInfront, list);
// Check if the number two square infront of the pawn is empty and that the rank is 2.
if (Conversion.getRanksBrd(sq) == (int)Rank.RANK_2 &&
board[sq + 20] == (int)Piece.EMPTY)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove(sq, sq + 20, (int)Piece.EMPTY,
(int)Piece.EMPTY, MoveOperations.MoveFlagPawnStart), list);
}
}
else // BLACK
{
MoveGen.AddBlackPawnMove(board, sq, sqInfront, list);
// Check if the number two square infront of the pawn is empty and that the rank is 7.
if (Conversion.getRanksBrd(sq) == (int)Rank.RANK_7 &&
board[sq - 20] == (int)Piece.EMPTY)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove(sq, sq - 20, (int)Piece.EMPTY,
(int)Piece.EMPTY, MoveOperations.MoveFlagPawnStart), list);
}
}
}
}
if (Validators.IsSq(leftCaptureSq) &&
Data.PIECE_COLOURS[board[leftCaptureSq]] == (Colour)((int)side ^ 1))
{
if (side == Colour.WHITE)
{
MoveGen.AddWhitePawnCapMove(board, sq, leftCaptureSq, board[leftCaptureSq],
list);
}
else
{
// BLACK
MoveGen.AddBlackPawnCapMove(board, sq, leftCaptureSq, board[leftCaptureSq],
list);
}
}
if (Validators.IsSq(rightCaptureSq) &&
Data.PIECE_COLOURS[board[rightCaptureSq]] == (Colour)((int)side ^ 1))
{
if (side == Colour.WHITE)
{
MoveGen.AddWhitePawnCapMove(board, sq, rightCaptureSq,
board[rightCaptureSq], list);
}
else
{
// BLACK
MoveGen.AddBlackPawnCapMove(board, sq, rightCaptureSq,
board[rightCaptureSq], list);
}
}
if (Validators.IsSq(board.EnPas))
{
if (leftCaptureSq == board.EnPas)
{
MoveGen.AddEnPassantMove(board, MoveOperations.CreateMove(sq, leftCaptureSq,
(int)Piece.EMPTY
, (int)Piece.EMPTY, MoveOperations.MoveFlagEnPas), list);
}
else if (rightCaptureSq == board.EnPas)
{
MoveGen.AddEnPassantMove(board, MoveOperations.CreateMove(sq,
rightCaptureSq, (int)Piece.EMPTY
, (int)Piece.EMPTY, MoveOperations.MoveFlagEnPas), list);
}
}
}
// Castling
if (!onlyCaptures)
{
if (side == Colour.WHITE)
{
// If there is White King Castle Permission.
if ((board.CastlePerm & (int)Castling.WKCA) != 0)
{
// Check if squares are empty before we call the less efficient SqAttacked method.
var isSqG1F1Empty = board[(int)Square.F1] == (int)Piece.EMPTY && board[
(int)Square.G1] == (int)Piece.EMPTY;
if (isSqG1F1Empty)
{
var IsSqE1OrF1NotAtt =
!Attack.IsSqAttacked((int)Square.F1, (int)Colour.BLACK, board) &&
!Attack.IsSqAttacked((int)Square.E1, (int)Colour.BLACK, board);
if (IsSqE1OrF1NotAtt)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove((int)Square.E1, (int)Square.G1,
(int)Piece.EMPTY, (int)Piece.EMPTY,
MoveOperations.MoveFlagCastle), list);
}
}
}
// If there is White Queen Castle Permission.
if ((board.CastlePerm & (int)Castling.WQCA) != 0)
{
var isSqB1C1D1Empty = board[(int)Square.B1] == (int)Piece.EMPTY &&
board[(int)Square.C1] == (int)Piece.EMPTY &&
board[(int)Square.D1] == (int)Piece.EMPTY;
if (isSqB1C1D1Empty)
{
var isSqE1OrD1NotAtt =
!Attack.IsSqAttacked((int)Square.E1, (int)Colour.BLACK, board) &&
!Attack.IsSqAttacked((int)Square.D1, (int)Colour.BLACK, board);
if (isSqE1OrD1NotAtt)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove((int)Square.E1, (int)Square.C1,
(int)Piece.EMPTY, (int)Piece.EMPTY,
MoveOperations.MoveFlagCastle), list);
}
}
}
}
else
{
// If there is Black King Castle Permission.
if ((board.CastlePerm & (int)Castling.BKCA) != 0)
{
// Check if squares are empty before we call the less efficient SqAttacked method.
var isSqG8F8Empty = board[(int)Square.F8] == (int)Piece.EMPTY &&
board[(int)Square.G8] == (int)Piece.EMPTY;
if (isSqG8F8Empty)
{
var isSqE8F8NotAttacked =
!Attack.IsSqAttacked((int)Square.E8, (int)Colour.WHITE, board) &&
!Attack.IsSqAttacked((int)Square.F8, (int)Colour.WHITE, board);
if (isSqE8F8NotAttacked)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove((int)Square.E8, (int)Square.G8,
(int)Piece.EMPTY, (int)Piece.EMPTY,
MoveOperations.MoveFlagCastle), list);
}
}
}
// If there is White Queen Castle Permission.
if ((board.CastlePerm & (int)Castling.BQCA) != 0)
{
// Check if squares are empty before we call the less efficient SqAttacked method.
var isSqB8C8D8Empty = board[(int)Square.B8] == (int)Piece.EMPTY &&
board[(int)Square.C8] == (int)Piece.EMPTY &&
board[(int)Square.D8] == (int)Piece.EMPTY;
if (isSqB8C8D8Empty)
{
var isSqE8D8NotAttacked =
!Attack.IsSqAttacked((int)Square.E8, (int)Colour.WHITE, board) &&
!Attack.IsSqAttacked((int)Square.D8, (int)Colour.WHITE, board);
if (isSqE8D8NotAttacked)
{
MoveGen.AddQuietMove(board,
MoveOperations.CreateMove((int)Square.E8, (int)Square.C8,
(int)Piece.EMPTY, (int)Piece.EMPTY,
MoveOperations.MoveFlagCastle), list);
}
}
}
}
}
// Loop sliding pieces
var pceIndex = MoveGen.LOOP_SLIDE_INDEX[board.Side];
// Increments AFTER it's run
var pce = MoveGen.LOOP_SLIDE_PCE[pceIndex++];
while (pce != 0)
{
Debug.Assert(Validators.PieceValid(pce),
String.Format("You have reached an invalid sliding piece {0}", pce));
for (var pceNum = 0; pceNum < board.PceNum[pce]; ++pceNum)
{
var sq = board.PList[pce, pceNum];
// Square check
Debug.Assert(Validators.IsSq(sq), String.Format("Sq {0} is false", sq));
for (var index = 0; index < MoveGen.NUM_DIR[pce]; ++index)
{
var t_sq = sq + MoveGen.PCE_DIR[pce, index];
// Check if offboard
if (!Validators.SqOnBoard(t_sq))
{
continue;
}
while (Validators.SqOnBoard(t_sq))
{
if (board[t_sq] != (int)Piece.EMPTY)
{
// 0 EXCLUSIVE OR 1 returns 1 = COLOUR.WHITE
// 1 EXCLUSIVE OR 1 returns 0 = COLOUR.BLACK
if ((int)Data.PIECE_COLOURS[board[t_sq]] == (board.Side ^ 1))
{
AddCaptureMove(board, MoveOperations.CreateMove(sq, t_sq, board[t_sq], (int)Piece.EMPTY, 0), list);
}
break;
}
if (!onlyCaptures)
{
AddQuietMove(board,
MoveOperations.CreateMove(sq, t_sq, (int)Piece.EMPTY,
(int)Piece.EMPTY, 0), list);
}
t_sq += MoveGen.PCE_DIR[pce, index];
}
}
}
pce = MoveGen.LOOP_SLIDE_PCE[pceIndex++];
}
// Loop non_sliding pieces
pceIndex = MoveGen.LOOP_NON_SLIDE_INDEX[board.Side];
pce = MoveGen.LOOP_NON_SLIDE_PCE[pceIndex++];
while (pce != 0)
{
Debug.Assert(Validators.PieceValid(pce), String.Format("You have reached an invalid sliding piece {0}", pce));
for (var pceNum = 0; pceNum < board.PceNum[pce]; ++pceNum)
{
var sq = board.PList[pce, pceNum];
// Square check
Debug.Assert(Validators.IsSq(sq), String.Format("Sq {0} is invalid", sq));
for (var index = 0; index < MoveGen.NUM_DIR[pce]; ++index)
{
var t_sq = sq + MoveGen.PCE_DIR[pce, index];
// Check if offboard
if (!Validators.SqOnBoard(t_sq))
{
continue;
}
if (board[t_sq] != (int)Piece.EMPTY)
{
// 0 EXCLUSIVE OR 1 returns 1 = COLOUR.WHITE
// 1 EXCLUSIVE OR 1 returns 0 = COLOUR.BLACK
if ((int)Data.PIECE_COLOURS[board[t_sq]] == (board.Side ^ 1))
{
AddCaptureMove(board, MoveOperations.CreateMove(sq, t_sq, board[t_sq], (int)Piece.EMPTY, 0), list);
}
continue;
}
if (!onlyCaptures)
{
AddQuietMove(board,
MoveOperations.CreateMove(sq, t_sq, (int)Piece.EMPTY,
(int)Piece.EMPTY, 0), list);
}
}
}
pce = MoveGen.LOOP_NON_SLIDE_PCE[pceIndex++];
}
}
