private void MakeCastlingMove(Move move)
{
var rookSrcIx = CastlingTables.GetCastlingRookSrcIx(move.DstIx);
var rookDstIx = CastlingTables.GetCastlingRookDstIx(move.DstIx);
MovePiece(move.SourceIx, move.DstIx, SideMoving, PieceType.King);
MovePiece(rookSrcIx, rookDstIx, SideMoving, PieceType.Rook);
}
public static Position MakeMove(Position shell, Move move, Position parent)
{
// copy data which doesn't depend on performing the move
parent.CopyPieceBitboards(ref shell._pieceBitboards);
parent.CopySquares(ref shell._squares);
shell.ZobristHash = parent.ZobristHash;
shell.Parent = parent;
shell._inCheckWhite = null;
shell._inCheckBlack = null;
shell.SideToMove = parent.SideToMove.Other();
shell.EnPassant = 0; // this gets set for double moves
shell.FiftyMoveCounter = CalculateFiftyMoveCounter(parent, move);
shell.GamePly = parent.GamePly + 1;
shell._historyPly = parent._historyPly + 1;
switch (move.MoveType)
{
case MoveType.Normal | MoveType.Quiet:
shell.MakeNormalQuietMove(move);
break;
case MoveType.Normal | MoveType.Capture:
shell.MakeNormalCaptureMove(move);
break;
case MoveType.DoubleMove | MoveType.Quiet:
shell.MakeDoublePawnMove(move);
break;
case MoveType.EnPassant | MoveType.Capture:
shell.MakeEnPassantMove(move);
break;
case MoveType.Promotion | MoveType.Quiet:
shell.MakePromotionQuietMove(move);
break;
case MoveType.Promotion | MoveType.Capture:
shell.MakePromotionCaptureMove(move);
break;
case MoveType.Castling | MoveType.Quiet:
shell.MakeCastlingMove(move);
break;
default:
throw new Exception($"Invalid move type: {move.MoveType}");
}
shell.CastlingRights = parent.CastlingRights & CastlingTables.GetCastlingUpdateMask(move);
shell._occupiedWhite = shell.CalculateOccupied(Color.White);
shell._occupiedBlack = shell.CalculateOccupied(Color.Black);
shell._occupied = shell._occupiedWhite | shell._occupiedBlack;
shell.ZobristHash ^= ZobristHashing.OtherHashDiff(parent, shell);
shell.RepetitionNumber = CalculateRepetitionNumber(shell);
return(shell);
}
private void GenerateKingCastling(List <Move> moves, Position position)
{
var castlingDsts = position.CastlingRights & CastlingTables.GetCastlingRightsDstColorMask(position.SideToMove);
while (Bits.TryPopLsb(ref castlingDsts, out var dstIx))
{
if ((position.GetOccupied() & CastlingTables.GetCastlingEmptySquares(dstIx)) > 0)
{
continue;
}
if (position.InCheck(position.SideToMove))
{
continue;
}
bool attacked = false;
foreach (var potentiallyAttackedIx in Bits.Enumerate(CastlingTables.GetCastlingAttacks(dstIx)))
{
if (position.IsAttacked(potentiallyAttackedIx, position.SideToMove))
{
attacked = true;
break;
}
}
if (attacked)
{
continue;
}
// if we still have castling rights, the inbetween squares aren't occupied, we aren't in check, and we aren't castling through or into check, then we should be good to go!
int kingIx = Bits.GetLsb(position.GetPieceBitboard(position.SideToMove, PieceType.King));
moves.Add(new Move(MoveType.Castling | MoveType.Quiet, kingIx, dstIx));
}
}
