public static int GetLoudMoves(BoardState boardState, Span <Move> moves, int offset, ulong evasionMask)
{
var color = boardState.ColorToMove;
var enemyColor = ColorOperations.Invert(color);
var bishops = boardState.Pieces[color][Piece.Bishop];
while (bishops != 0)
{
var piece = BitOperations.GetLsb(bishops);
bishops = BitOperations.PopLsb(bishops);
var from = BitOperations.BitScan(piece);
var availableMoves = BishopMovesGenerator.GetMoves(boardState.OccupancySummary, from) & boardState.Occupancy[enemyColor];
availableMoves &= evasionMask;
while (availableMoves != 0)
{
var field = BitOperations.GetLsb(availableMoves);
var fieldIndex = BitOperations.BitScan(field);
availableMoves = BitOperations.PopLsb(availableMoves);
moves[offset++] = new Move(from, fieldIndex, MoveFlags.Capture);
}
}
return(offset);
}
public static int GetMobility(BoardState boardState, int color, ref ulong fieldsAttackedByColor)
{
var centerMobility = 0;
var extendedCenterMobility = 0;
var outsideMobility = 0;
var bishops = boardState.Pieces[color][Piece.Bishop];
while (bishops != 0)
{
var piece = BitOperations.GetLsb(bishops);
bishops = BitOperations.PopLsb(bishops);
var from = BitOperations.BitScan(piece);
var availableMoves = BishopMovesGenerator.GetMoves(boardState.OccupancySummary, from);
centerMobility += (int)BitOperations.Count(availableMoves & EvaluationConstants.Center);
extendedCenterMobility += (int)BitOperations.Count(availableMoves & EvaluationConstants.ExtendedCenter);
outsideMobility += (int)BitOperations.Count(availableMoves & EvaluationConstants.Outside);
fieldsAttackedByColor |= availableMoves;
}
return(EvaluationConstants.CenterMobilityModifier * centerMobility +
EvaluationConstants.ExtendedCenterMobilityModifier * extendedCenterMobility +
EvaluationConstants.OutsideMobilityModifier * outsideMobility);
}
public byte GetAttackingPiecesWithColor(int color, int fieldIndex)
{
byte result = 0;
var jumpAttacks = KnightMovesGenerator.GetMoves(fieldIndex);
var attackingKnights = jumpAttacks & Pieces[color][Piece.Knight];
var attackingKnightsCount = BitOperations.Count(attackingKnights);
if (attackingKnightsCount != 0)
{
result |= (byte)((attackingKnightsCount == 1 ? 1 : 3) << SeePiece.Knight1);
}
var diagonalAttacks = BishopMovesGenerator.GetMoves(OccupancySummary, fieldIndex) & Occupancy[color];
var attackingBishops = diagonalAttacks & Pieces[color][Piece.Bishop];
if (attackingBishops != 0)
{
result |= 1 << SeePiece.Bishop;
}
var occupancyWithoutFileRankPieces = OccupancySummary & ~Pieces[color][Piece.Rook] & ~Pieces[color][Piece.Queen];
var fileRankAttacks = RookMovesGenerator.GetMoves(occupancyWithoutFileRankPieces, fieldIndex) & Occupancy[color];
var attackingRooks = fileRankAttacks & Pieces[color][Piece.Rook];
var attackingRooksCount = BitOperations.Count(attackingRooks);
if (attackingRooksCount != 0)
{
result |= (byte)((attackingRooksCount == 1 ? 1 : 3) << SeePiece.Rook1);
}
var attackingQueens = (fileRankAttacks | diagonalAttacks) & Pieces[color][Piece.Queen];
if (attackingQueens != 0)
{
result |= 1 << SeePiece.Queen;
}
var boxAttacks = KingMovesGenerator.GetMoves(fieldIndex);
var attackingKings = boxAttacks & Pieces[color][Piece.King];
if (attackingKings != 0)
{
result |= 1 << SeePiece.King;
}
var field = 1ul << fieldIndex;
var potentialPawns = boxAttacks & Pieces[color][Piece.Pawn];
var attackingPawns = color == Color.White ?
field & ((potentialPawns << 7) | (potentialPawns << 9)) :
field & ((potentialPawns >> 7) | (potentialPawns >> 9));
if (attackingPawns != 0)
{
result |= 1 << SeePiece.Pawn;
}
return(result);
}
public bool IsFieldAttacked(int color, int fieldIndex)
{
var enemyColor = ColorOperations.Invert(color);
var fileRankAttacks = RookMovesGenerator.GetMoves(OccupancySummary, fieldIndex) & Occupancy[enemyColor];
var attackingRooks = fileRankAttacks & (Pieces[enemyColor][Piece.Rook] | Pieces[enemyColor][Piece.Queen]);
if (attackingRooks != 0)
{
return(true);
}
var diagonalAttacks = BishopMovesGenerator.GetMoves(OccupancySummary, fieldIndex) & Occupancy[enemyColor];
var attackingBishops = diagonalAttacks & (Pieces[enemyColor][Piece.Bishop] | Pieces[enemyColor][Piece.Queen]);
if (attackingBishops != 0)
{
return(true);
}
var jumpAttacks = KnightMovesGenerator.GetMoves(fieldIndex);
var attackingKnights = jumpAttacks & Pieces[enemyColor][Piece.Knight];
if (attackingKnights != 0)
{
return(true);
}
var boxAttacks = KingMovesGenerator.GetMoves(fieldIndex);
var attackingKings = boxAttacks & Pieces[enemyColor][Piece.King];
if (attackingKings != 0)
{
return(true);
}
var field = 1ul << fieldIndex;
var potentialPawns = boxAttacks & Pieces[enemyColor][Piece.Pawn];
var attackingPawns = color == Color.White ?
field & ((potentialPawns >> 7) | (potentialPawns >> 9)) :
field & ((potentialPawns << 7) | (potentialPawns << 9));
if (attackingPawns != 0)
{
return(true);
}
return(false);
}
public static bool IsMoveLegal(BoardState boardState, Move move)
{
var enemyColor = ColorOperations.Invert(boardState.ColorToMove);
var availableMoves = BishopMovesGenerator.GetMoves(boardState.OccupancySummary, move.From);
var toField = 1ul << move.To;
if (move.IsSinglePush() && (availableMoves & toField) != 0 && (boardState.OccupancySummary & toField) == 0)
{
return(true);
}
if (move.IsCapture() && (availableMoves & toField) != 0 && (boardState.Occupancy[enemyColor] & toField) != 0)
{
return(true);
}
return(false);
}