/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 Marco Costalba
+ Copyright (C) 2008-2009 Marco Costalba
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
// Evaluation grain size, must be a power of 2.
const int GrainSize = 4;
- // Evaluation weights
- int WeightMobilityMidgame = 0x100;
- int WeightMobilityEndgame = 0x100;
- int WeightPawnStructureMidgame = 0x100;
- int WeightPawnStructureEndgame = 0x100;
- int WeightPassedPawnsMidgame = 0x100;
- int WeightPassedPawnsEndgame = 0x100;
- int WeightKingSafety[2] = { 0x100, 0x100 };
+ // Evaluation weights, initialized from UCI options
+ int WeightMobilityMidgame, WeightMobilityEndgame;
+ int WeightPawnStructureMidgame, WeightPawnStructureEndgame;
+ int WeightPassedPawnsMidgame, WeightPassedPawnsEndgame;
+ int WeightKingSafety[2];
int WeightSpace;
// Internal evaluation weights. These are applied on top of the evaluation
const int BishopAttackWeight = 2;
const int KnightAttackWeight = 2;
- // Bonuses for safe checks for each piece type.
- int QueenContactCheckBonus = 3;
- int QueenCheckBonus = 2;
- int RookCheckBonus = 1;
- int BishopCheckBonus = 1;
- int KnightCheckBonus = 1;
- int DiscoveredCheckBonus = 3;
+ // Bonuses for safe checks, initialized from UCI options
+ int QueenContactCheckBonus, DiscoveredCheckBonus;
+ int QueenCheckBonus, RookCheckBonus, BishopCheckBonus, KnightCheckBonus;
// Scan for queen contact mates?
const bool QueenContactMates = true;
- // Bonus for having a mate threat.
- int MateThreatBonus = 3;
+ // Bonus for having a mate threat, initialized from UCI options
+ int MateThreatBonus;
// InitKingDanger[] contains bonuses based on the position of the defending
// king.
void evaluate_space(const Position &p, Color us, EvalInfo &ei);
inline Value apply_weight(Value v, int w);
+ Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]);
int count_1s_8bit(Bitboard b);
}
for (Bitboard b = 0ULL; b < 256ULL; b++)
- BitCount8Bit[b] = count_1s(b);
+ {
+ assert(count_1s(b) == int(uint8_t(count_1s(b))));
+ BitCount8Bit[b] = (uint8_t)count_1s(b);
+ }
}
{
delete PawnTable[i];
delete MaterialTable[i];
+ PawnTable[i] = NULL;
+ MaterialTable[i] = NULL;
}
}
}
-/// scale_by_game_phase() interpolates between a middle game and an endgame
-/// score, based on game phase. It also scales the return value by a
-/// ScaleFactor array.
-
-Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) {
-
- assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
- assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
- assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
-
- ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
-
- Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
- return Value(int(result) & ~(GrainSize - 1));
-}
-
namespace {
// evaluate_common() computes terms common to all pieces attack
ei.egMobility += Sign[us] * EgBonus[Piece][mob];
// Bishop and Knight outposts
- if ( (Piece != BISHOP && Piece != KNIGHT) // compile time condition
- || !p.square_is_weak(s, them))
- return mob;
-
- // Initial bonus based on square
- Value v, bonus;
- v = bonus = OutpostBonus[Piece][relative_square(us, s)];
-
- // Increase bonus if supported by pawn, especially if the opponent has
- // no minor piece which can exchange the outpost piece
- if (v && (p.pawn_attacks(them, s) & p.pawns(us)))
+ if ( (Piece == BISHOP || Piece == KNIGHT) // compile time condition
+ && p.square_is_weak(s, them))
{
- bonus += v / 2;
- if ( p.piece_count(them, KNIGHT) == 0
- && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
- bonus += v;
+ // Initial bonus based on square
+ Value v, bonus;
+ v = bonus = OutpostBonus[Piece][relative_square(us, s)];
+
+ // Increase bonus if supported by pawn, especially if the opponent has
+ // no minor piece which can exchange the outpost piece
+ if (v && (p.pawn_attacks(them, s) & p.pawns(us)))
+ {
+ bonus += v / 2;
+ if ( p.piece_count(them, KNIGHT) == 0
+ && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
+ bonus += v;
+ }
+ ei.mgValue += Sign[us] * bonus;
+ ei.egValue += Sign[us] * bonus;
}
- ei.mgValue += Sign[us] * bonus;
- ei.egValue += Sign[us] * bonus;
return mob;
}
evaluate_trapped_bishop_a1h1(pos, s, us, ei);
}
- if (Piece != ROOK && Piece != QUEEN)
- continue;
-
- // Queen or rook on 7th rank
- them = opposite_color(us);
-
- if ( relative_rank(us, s) == RANK_7
- && relative_rank(us, pos.king_square(them)) == RANK_8)
+ if (Piece == ROOK || Piece == QUEEN)
{
- ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
- ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ // Queen or rook on 7th rank
+ them = opposite_color(us);
+
+ if ( relative_rank(us, s) == RANK_7
+ && relative_rank(us, pos.king_square(them)) == RANK_8)
+ {
+ ei.mgValue += Sign[us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
+ ei.egValue += Sign[us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
+ }
}
// Special extra evaluation for rooks
- if (Piece != ROOK)
- continue;
-
- // Open and half-open files
- f = square_file(s);
- if (ei.pi->file_is_half_open(us, f))
+ if (Piece == ROOK)
{
- if (ei.pi->file_is_half_open(them, f))
+ // Open and half-open files
+ f = square_file(s);
+ if (ei.pi->file_is_half_open(us, f))
{
- ei.mgValue += Sign[us] * RookOpenFileBonus;
- ei.egValue += Sign[us] * RookOpenFileBonus;
- }
- else
- {
- ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
- ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ if (ei.pi->file_is_half_open(them, f))
+ {
+ ei.mgValue += Sign[us] * RookOpenFileBonus;
+ ei.egValue += Sign[us] * RookOpenFileBonus;
+ }
+ else
+ {
+ ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
+ ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ }
}
- }
- // Penalize rooks which are trapped inside a king. Penalize more if
- // king has lost right to castle.
- if (mob > 6 || ei.pi->file_is_half_open(us, f))
- continue;
+ // Penalize rooks which are trapped inside a king. Penalize more if
+ // king has lost right to castle.
+ if (mob > 6 || ei.pi->file_is_half_open(us, f))
+ continue;
- ksq = pos.king_square(us);
+ ksq = pos.king_square(us);
- if ( square_file(ksq) >= FILE_E
- && square_file(s) > square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
- }
- else if ( square_file(ksq) <= FILE_D
- && square_file(s) < square_file(ksq)
- && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
- {
- // Is there a half-open file between the king and the edge of the board?
- if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
- ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
+ if ( square_file(ksq) >= FILE_E
+ && square_file(s) > square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_right(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
+ else if ( square_file(ksq) <= FILE_D
+ && square_file(s) < square_file(ksq)
+ && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s)))
+ {
+ // Is there a half-open file between the king and the edge of the board?
+ if (!ei.pi->has_open_file_to_left(us, square_file(ksq)))
+ ei.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[us] * (TrappedRookPenalty - mob * 16);
+ }
}
}
}
// King shelter
if (relative_rank(us, s) <= RANK_4)
{
- Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
- Rank r = square_rank(s);
- for (int i = 1; i < 4; i++)
- shelter += count_1s_8bit(shiftRowsDown(pawns, r+i*sign)) * (128>>i);
-
+ // Shelter cache lookup
+ shelter = ei.pi->kingShelter(us, s);
+ if (shelter == -1)
+ {
+ shelter = 0;
+ Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s);
+ Rank r = square_rank(s);
+ for (int i = 1; i < 4; i++)
+ shelter += count_1s_8bit(shiftRowsDown(pawns, r+i*sign)) * (128>>i);
+
+ // Cache shelter value in pawn info
+ ei.pi->setKingShelter(us, s, shelter);
+ }
ei.mgValue += sign * Value(shelter);
}
if ( bit_is_set(p.piece_attacks<QUEEN>(from), to)
&& !bit_is_set(p.pinned_pieces(them), from)
&& !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))
- && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us)))
+ && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & p.bishops_and_queens(us)))
ei.mateThreat[them] = make_move(from, to);
}
}
+ // scale_by_game_phase() interpolates between a middle game and an endgame
+ // score, based on game phase. It also scales the return value by a
+ // ScaleFactor array.
+
+ Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) {
+
+ assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
+ assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
+ assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
+
+ ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
+
+ Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
+ return Value(int(result) & ~(GrainSize - 1));
+ }
+
+
// count_1s_8bit() counts the number of nonzero bits in the 8 least
// significant bits of a Bitboard. This function is used by the king
// shield evaluation.
projects / stockfish / blobdiff