/*
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
namespace {
- const int Sign[2] = {1, -1};
+ const int Sign[2] = { 1, -1 };
- // Evaluation grain size, must be a power of 2.
+ // 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
- // weights read from UCI parameters. The purpose is to be able to change
+ // Internal evaluation weights. These are applied on top of the evaluation
+ // weights read from UCI parameters. The purpose is to be able to change
// the evaluation weights while keeping the default values of the UCI
// parameters at 100, which looks prettier.
- const int WeightMobilityMidgameInternal = 0x100;
- const int WeightMobilityEndgameInternal = 0x100;
- const int WeightPawnStructureMidgameInternal = 0x100;
- const int WeightPawnStructureEndgameInternal = 0x100;
- const int WeightPassedPawnsMidgameInternal = 0x100;
- const int WeightPassedPawnsEndgameInternal = 0x100;
- const int WeightKingSafetyInternal = 0x110;
- const int WeightKingOppSafetyInternal = 0x110;
- const int WeightSpaceInternal = 0x30;
+ //
+ // Values modified by Joona Kiiski
+ const int WeightMobilityMidgameInternal = 0x0FA;
+ const int WeightMobilityEndgameInternal = 0x10A;
+ const int WeightPawnStructureMidgameInternal = 0x0EC;
+ const int WeightPawnStructureEndgameInternal = 0x0CD;
+ const int WeightPassedPawnsMidgameInternal = 0x108;
+ const int WeightPassedPawnsEndgameInternal = 0x109;
+ const int WeightKingSafetyInternal = 0x0F7;
+ const int WeightKingOppSafetyInternal = 0x101;
+ const int WeightSpaceInternal = 0x02F;
// Visually better to define tables constants
typedef Value V;
};
// Bishop mobility bonus in middle game and endgame, indexed by the number
- // of attacked squares not occupied by friendly pieces. X-ray attacks through
+ // of attacked squares not occupied by friendly pieces. X-ray attacks through
// queens are also included.
const Value MidgameBishopMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
};
// Rook mobility bonus in middle game and endgame, indexed by the number
- // of attacked squares not occupied by friendly pieces. X-ray attacks through
+ // of attacked squares not occupied by friendly pieces. X-ray attacks through
// queens and rooks are also included.
const Value MidgameRookMobilityBonus[] = {
// 0 1 2 3 4 5 6 7
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8
};
- // Bonus for unstoppable passed pawns:
+ // Bonus for unstoppable passed pawns
const Value UnstoppablePawnValue = Value(0x500);
- // Rooks and queens on the 7th rank:
- const Value MidgameRookOn7thBonus = Value(50);
- const Value EndgameRookOn7thBonus = Value(100);
- const Value MidgameQueenOn7thBonus = Value(25);
- const Value EndgameQueenOn7thBonus = Value(50);
+ // Rooks and queens on the 7th rank
+ const Value MidgameRookOn7thBonus = Value(47);
+ const Value EndgameRookOn7thBonus = Value(98);
+ const Value MidgameQueenOn7thBonus = Value(27);
+ const Value EndgameQueenOn7thBonus = Value(54);
- // Rooks on open files:
- const Value RookOpenFileBonus = Value(40);
- const Value RookHalfOpenFileBonus = Value(20);
+ // Rooks on open files
+ const Value RookOpenFileBonus = Value(43);
+ const Value RookHalfOpenFileBonus = Value(19);
// Penalty for rooks trapped inside a friendly king which has lost the
- // right to castle:
+ // right to castle.
const Value TrappedRookPenalty = Value(180);
// Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by
- // enemy pawns:
+ // enemy pawns.
const Value TrappedBishopA7H7Penalty = Value(300);
- // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black):
+ // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black)
const Bitboard MaskA7H7[2] = {
((1ULL << SQ_A7) | (1ULL << SQ_H7)),
((1ULL << SQ_A2) | (1ULL << SQ_H2))
};
// Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
- // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
+ // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
// happen in Chess960 games.
const Value TrappedBishopA1H1Penalty = Value(100);
- // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black):
+ // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black)
const Bitboard MaskA1H1[2] = {
((1ULL << SQ_A1) | (1ULL << SQ_H1)),
((1ULL << SQ_A8) | (1ULL << SQ_H8))
};
// The SpaceMask[color] contains area of the board which is consdered by
- // the space evaluation. In the middle game, each side is given a bonus
+ // the space evaluation. In the middle game, each side is given a bonus
// based on how many squares inside this area are safe and available for
// friendly minor pieces.
const Bitboard SpaceMask[2] = {
(1ULL<<SQ_C5) | (1ULL<<SQ_D5) | (1ULL<<SQ_E5) | (1ULL<<SQ_F5)
};
- /// King safety constants and variables. The king safety scores are taken
- /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
+ /// King safety constants and variables. The king safety scores are taken
+ /// from the array SafetyTable[]. Various little "meta-bonuses" measuring
/// the strength of the attack are added up into an integer, which is used
/// as an index to SafetyTable[].
- // Attack weights for each piece type.
+ // Attack weights for each piece type
const int QueenAttackWeight = 5;
const int RookAttackWeight = 3;
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.
15, 15, 15, 15, 15, 15, 15, 15
};
- // SafetyTable[] contains the actual king safety scores. It is initialized
+ // SafetyTable[] contains the actual king safety scores. It is initialized
// in init_safety().
Value SafetyTable[100];
// Pawn and material hash tables, indexed by the current thread id
- PawnInfoTable *PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
- MaterialInfoTable *MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ PawnInfoTable* PawnTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+ MaterialInfoTable* MaterialTable[8] = {0, 0, 0, 0, 0, 0, 0, 0};
// Sizes of pawn and material hash tables
const int PawnTableSize = 16384;
const int MaterialTableSize = 1024;
- // Array which gives the number of nonzero bits in an 8-bit integer:
+ // Array which gives the number of nonzero bits in an 8-bit integer
uint8_t BitCount8Bit[256];
// Function prototypes
- void evaluate_knight(const Position &p, Square s, Color us, EvalInfo &ei);
- void evaluate_bishop(const Position &p, Square s, Color us, EvalInfo &ei);
- void evaluate_rook(const Position &p, Square s, Color us, EvalInfo &ei);
- void evaluate_queen(const Position &p, Square s, Color us, EvalInfo &ei);
- void evaluate_king(const Position &p, Square s, Color us, EvalInfo &ei);
+ template<PieceType Piece>
+ void evaluate_pieces(const Position& p, Color us, EvalInfo& ei);
+
+ template<>
+ void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo &ei);
void evaluate_passed_pawns(const Position &pos, EvalInfo &ei);
void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
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);
-
int compute_weight(int uciWeight, int internalWeight);
int weight_option(const std::string& opt, int weight);
void init_safety();
// Evaluate pieces
for (Color c = WHITE; c <= BLACK; c++)
{
- // Knights
- for (int i = 0; i < pos.piece_count(c, KNIGHT); i++)
- evaluate_knight(pos, pos.piece_list(c, KNIGHT, i), c, ei);
-
- // Bishops
- for (int i = 0; i < pos.piece_count(c, BISHOP); i++)
- evaluate_bishop(pos, pos.piece_list(c, BISHOP, i), c, ei);
-
- // Rooks
- for (int i = 0; i < pos.piece_count(c, ROOK); i++)
- evaluate_rook(pos, pos.piece_list(c, ROOK, i), c, ei);
-
- // Queens
- for(int i = 0; i < pos.piece_count(c, QUEEN); i++)
- evaluate_queen(pos, pos.piece_list(c, QUEEN, i), c, ei);
-
- // Special pattern: trapped bishops on a7/h7/a2/h2
- Bitboard b = pos.bishops(c) & MaskA7H7[c];
- while (b)
- {
- Square s = pop_1st_bit(&b);
- evaluate_trapped_bishop_a7h7(pos, s, c, ei);
- }
-
- // Special pattern: trapped bishops on a1/h1/a8/h8 in Chess960:
- if (Chess960)
- {
- b = pos.bishops(c) & MaskA1H1[c];
- while (b)
- {
- Square s = pop_1st_bit(&b);
- evaluate_trapped_bishop_a1h1(pos, s, c, ei);
- }
- }
-
- // Sum up all attacked squares
- ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
- | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK]
- | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING];
+ evaluate_pieces<KNIGHT>(pos, c, ei);
+ evaluate_pieces<BISHOP>(pos, c, ei);
+ evaluate_pieces<ROOK>(pos, c, ei);
+ evaluate_pieces<QUEEN>(pos, c, ei);
+
+ // Sum up all attacked squares
+ ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT]
+ | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK]
+ | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING];
}
// Kings. Kings are evaluated after all other pieces for both sides,
// because we need complete attack information for all pieces when computing
// the king safety evaluation.
for (Color c = WHITE; c <= BLACK; c++)
- evaluate_king(pos, pos.king_square(c), c, ei);
+ evaluate_pieces<KING>(pos, c, ei);
// Evaluate passed pawns. We evaluate passed pawns for both sides at once,
// because we need to know which side promotes first in positions where
assert(pos.is_ok());
static const
- ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};
+ ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};
Value mgv = pos.mg_value();
Value egv = pos.eg_value();
}
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;
}
}
// evaluate_common() computes terms common to all pieces attack
- int evaluate_common(const Position&p, const Bitboard& b, Color us, EvalInfo& ei,
- int AttackWeight, const Value* mgBonus, const Value* egBonus,
- Square s = SQ_NONE, const Value* OutpostBonus = NULL) {
+ template<PieceType Piece>
+ int evaluate_common(const Position& p, const Bitboard& b, Color us, EvalInfo& ei, Square s = SQ_NONE) {
+
+ static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight };
+ static const Value* MgBonus[] = { 0, 0, MidgameKnightMobilityBonus, MidgameBishopMobilityBonus, MidgameRookMobilityBonus, MidgameQueenMobilityBonus };
+ static const Value* EgBonus[] = { 0, 0, EndgameKnightMobilityBonus, EndgameBishopMobilityBonus, EndgameRookMobilityBonus, EndgameQueenMobilityBonus };
+ static const Value* OutpostBonus[] = { 0, 0, KnightOutpostBonus, BishopOutpostBonus, 0, 0 };
Color them = opposite_color(us);
+ // Update attack info
+ ei.attackedBy[us][Piece] |= b;
+
// King attack
if (b & ei.kingZone[us])
{
ei.kingAttackersCount[us]++;
- ei.kingAttackersWeight[us] += AttackWeight;
+ ei.kingAttackersWeight[us] += AttackWeight[Piece];
Bitboard bb = (b & ei.attackedBy[them][KING]);
if (bb)
ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15(bb);
}
- // Mobility
- int mob = count_1s_max_15(b & ~p.pieces_of_color(us));
- ei.mgMobility += Sign[us] * mgBonus[mob];
- ei.egMobility += Sign[us] * egBonus[mob];
+ // Remove squares protected by enemy pawns
+ Bitboard bb = (b & ~ei.attackedBy[them][PAWN]);
- // Bishop and Knight outposts
- if (!OutpostBonus || !p.square_is_weak(s, them))
- return mob;
+ // Mobility
+ int mob = (Piece != QUEEN ? count_1s_max_15(bb & ~p.pieces_of_color(us))
+ : count_1s(bb & ~p.pieces_of_color(us)));
- // Initial bonus based on square
- Value v, bonus;
- v = bonus = OutpostBonus[relative_square(us, s)];
+ ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
+ ei.egMobility += Sign[us] * EgBonus[Piece][mob];
- // 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)))
+ // Bishop and Knight outposts
+ 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_knight() assigns bonuses and penalties to a knight of a given
- // color on a given square.
-
- void evaluate_knight(const Position &p, Square s, Color us, EvalInfo &ei) {
-
- Bitboard b = p.piece_attacks<KNIGHT>(s);
- ei.attackedBy[us][KNIGHT] |= b;
-
- // King attack, mobility and outposts
- evaluate_common(p, b, us, ei, KnightAttackWeight, MidgameKnightMobilityBonus,
- EndgameKnightMobilityBonus, s, KnightOutpostBonus);
- }
-
-
- // evaluate_bishop() assigns bonuses and penalties to a bishop of a given
- // color on a given square.
-
- void evaluate_bishop(const Position &p, Square s, Color us, EvalInfo &ei) {
-
- Bitboard b = bishop_attacks_bb(s, p.occupied_squares() & ~p.queens(us));
- ei.attackedBy[us][BISHOP] |= b;
-
- // King attack, mobility and outposts
- evaluate_common(p, b, us, ei, BishopAttackWeight, MidgameBishopMobilityBonus,
- EndgameBishopMobilityBonus, s, BishopOutpostBonus);
- }
-
-
- // evaluate_rook() assigns bonuses and penalties to a rook of a given
- // color on a given square.
+ // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given
+ // color.
- void evaluate_rook(const Position &p, Square s, Color us, EvalInfo &ei) {
+ template<PieceType Piece>
+ void evaluate_pieces(const Position& pos, Color us, EvalInfo& ei) {
- Bitboard b = rook_attacks_bb(s, p.occupied_squares() & ~p.rooks_and_queens(us));
- ei.attackedBy[us][ROOK] |= b;
+ Bitboard b;
+ Square s, ksq;
+ Color them;
+ int mob;
+ File f;
- // King attack and mobility
- int mob = evaluate_common(p, b, us, ei, RookAttackWeight, MidgameRookMobilityBonus,
- EndgameRookMobilityBonus);
-
- // Rook on 7th rank
- Color them = opposite_color(us);
-
- if ( relative_rank(us, s) == RANK_7
- && relative_rank(us, p.king_square(them)) == RANK_8)
+ for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++)
{
- ei.mgValue += Sign[us] * MidgameRookOn7thBonus;
- ei.egValue += Sign[us] * EndgameRookOn7thBonus;
- }
-
- // Open and half-open files
- File f = square_file(s);
- if (ei.pi->file_is_half_open(us, f))
- {
- 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;
- }
- }
+ s = pos.piece_list(us, Piece, i);
- // 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))
- return;
+ if (Piece == KNIGHT || Piece == QUEEN)
+ b = pos.piece_attacks<Piece>(s);
+ else if (Piece == BISHOP)
+ b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.queens(us));
+ else if (Piece == ROOK)
+ b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us));
- Square ksq = p.king_square(us);
+ // Attacks, mobility and outposts
+ mob = evaluate_common<Piece>(pos, b, us, ei, s);
- 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 -= p.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 -= p.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2)
- : Sign[us] * (TrappedRookPenalty - mob * 16);
- }
- }
+ // Special patterns: trapped bishops on a7/h7/a2/h2
+ // and trapped bishops on a1/h1/a8/h8 in Chess960.
+ if (Piece == BISHOP)
+ {
+ if (bit_is_set(MaskA7H7[us], s))
+ evaluate_trapped_bishop_a7h7(pos, s, us, ei);
+ if (Chess960 && bit_is_set(MaskA1H1[us], s))
+ evaluate_trapped_bishop_a1h1(pos, s, us, ei);
+ }
- // evaluate_queen() assigns bonuses and penalties to a queen of a given
- // color on a given square.
+ if (Piece == ROOK || Piece == QUEEN)
+ {
+ // Queen or rook on 7th rank
+ them = opposite_color(us);
- void evaluate_queen(const Position &p, Square s, Color us, EvalInfo &ei) {
+ 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);
+ }
+ }
- Bitboard b = p.piece_attacks<QUEEN>(s);
- ei.attackedBy[us][QUEEN] |= b;
+ // Special extra evaluation for rooks
+ if (Piece == ROOK)
+ {
+ // Open and half-open files
+ f = square_file(s);
+ if (ei.pi->file_is_half_open(us, f))
+ {
+ 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;
+ }
+ }
- // King attack and mobility
- evaluate_common(p, b, us, ei, QueenAttackWeight, MidgameQueenMobilityBonus,
- EndgameQueenMobilityBonus);
+ // 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;
- // Queen on 7th rank
- Color them = opposite_color(us);
+ ksq = pos.king_square(us);
- if ( relative_rank(us, s) == RANK_7
- && relative_rank(us, p.king_square(them)) == RANK_8)
- {
- ei.mgValue += Sign[us] * MidgameQueenOn7thBonus;
- ei.egValue += Sign[us] * EndgameQueenOn7thBonus;
+ 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);
+ }
+ }
}
}
return b >> (num << 3);
}
- // evaluate_king() assigns bonuses and penalties to a king of a given
- // color on a given square.
+ // evaluate_pieces<KING>() assigns bonuses and penalties to a king of a given
+ // color.
- void evaluate_king(const Position &p, Square s, Color us, EvalInfo &ei) {
+ template<>
+ void evaluate_pieces<KING>(const Position& p, Color us, EvalInfo& ei) {
int shelter = 0, sign = Sign[us];
+ Square s = p.king_square(us);
// 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 += BitCount8Bit[shiftRowsDown(pawns, r+i*sign) & 0xFF] * (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);
}
}
// evaluate_passed_pawns() evaluates the passed pawns for both sides.
void evaluate_passed_pawns(const Position &pos, EvalInfo &ei) {
+
bool hasUnstoppable[2] = {false, false};
int movesToGo[2] = {100, 100};
- for(Color us = WHITE; us <= BLACK; us++) {
- Color them = opposite_color(us);
- Square ourKingSq = pos.king_square(us);
- Square theirKingSq = pos.king_square(them);
- Bitboard b = ei.pi->passed_pawns() & pos.pawns(us), b2, b3, b4;
-
- while(b) {
- Square s = pop_1st_bit(&b);
- assert(pos.piece_on(s) == pawn_of_color(us));
- assert(pos.pawn_is_passed(us, s));
-
- int r = int(relative_rank(us, s) - RANK_2);
- int tr = Max(0, r * (r-1));
- Square blockSq = s + pawn_push(us);
-
- // Base bonus based on rank:
- Value mbonus = Value(20 * tr);
- Value ebonus = Value(10 + r * r * 10);
-
- // Adjust bonus based on king proximity:
- ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr);
- ebonus -=
- Value(square_distance(ourKingSq, blockSq + pawn_push(us)) * 1 * tr);
- ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr);
-
- // If the pawn is free to advance, increase bonus:
- if(pos.square_is_empty(blockSq)) {
-
- b2 = squares_in_front_of(us, s);
- b3 = b2 & ei.attacked_by(them);
- b4 = b2 & ei.attacked_by(us);
- if((b2 & pos.pieces_of_color(them)) == EmptyBoardBB) {
- // There are no enemy pieces in the pawn's path! Are any of the
- // squares in the pawn's path attacked by the enemy?
- if(b3 == EmptyBoardBB)
- // No enemy attacks, huge bonus!
- ebonus += Value(tr * ((b2 == b4)? 17 : 15));
- else
- // OK, there are enemy attacks. Are those squares which are
- // attacked by the enemy also attacked by us? If yes, big bonus
- // (but smaller than when there are no enemy attacks), if no,
- // somewhat smaller bonus.
- ebonus += Value(tr * (((b3 & b4) == b3)? 13 : 8));
- }
- else {
- // There are some enemy pieces in the pawn's path. While this is
- // sad, we still assign a moderate bonus if all squares in the path
- // which are either occupied by or attacked by enemy pieces are
- // also attacked by us.
- if(((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB)
- ebonus += Value(tr * 6);
- }
- // At last, add a small bonus when there are no *friendly* pieces
- // in the pawn's path:
- if((b2 & pos.pieces_of_color(us)) == EmptyBoardBB)
- ebonus += Value(tr);
- }
+ for (Color us = WHITE; us <= BLACK; us++)
+ {
+ Color them = opposite_color(us);
+ Square ourKingSq = pos.king_square(us);
+ Square theirKingSq = pos.king_square(them);
+ Bitboard b = ei.pi->passed_pawns() & pos.pawns(us), b2, b3, b4;
- // If the pawn is supported by a friendly pawn, increase bonus.
- b2 = pos.pawns(us) & neighboring_files_bb(s);
- if(b2 & rank_bb(s))
- ebonus += Value(r * 20);
- else if(pos.pawn_attacks(them, s) & b2)
- ebonus += Value(r * 12);
-
- // If the other side has only a king, check whether the pawn is
- // unstoppable:
- if(pos.non_pawn_material(them) == Value(0)) {
- Square qsq;
- int d;
-
- qsq = relative_square(us, make_square(square_file(s), RANK_8));
- d = square_distance(s, qsq) - square_distance(theirKingSq, qsq)
- + ((us == pos.side_to_move())? 0 : 1);
-
- if(d < 0) {
- int mtg = RANK_8 - relative_rank(us, s);
- int blockerCount =
- count_1s_max_15(squares_in_front_of(us,s)&pos.occupied_squares());
- mtg += blockerCount;
- d += blockerCount;
- if(d < 0) {
- hasUnstoppable[us] = true;
- movesToGo[us] = Min(movesToGo[us], mtg);
+ while (b)
+ {
+ Square s = pop_1st_bit(&b);
+
+ assert(pos.piece_on(s) == piece_of_color_and_type(us, PAWN));
+ assert(pos.pawn_is_passed(us, s));
+
+ int r = int(relative_rank(us, s) - RANK_2);
+ int tr = Max(0, r * (r - 1));
+ Square blockSq = s + pawn_push(us);
+
+ // Base bonus based on rank
+ Value mbonus = Value(20 * tr);
+ Value ebonus = Value(10 + r * r * 10);
+
+ // Adjust bonus based on king proximity
+ if (tr != 0)
+ {
+ ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr);
+ ebonus -= Value(square_distance(ourKingSq, blockSq + pawn_push(us)) * 1 * tr);
+ ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr);
+
+ // If the pawn is free to advance, increase bonus
+ if (pos.square_is_empty(blockSq))
+ {
+ b2 = squares_in_front_of(us, s);
+ b3 = b2 & ei.attacked_by(them);
+ b4 = b2 & ei.attacked_by(us);
+
+ // If there is an enemy rook or queen attacking the pawn from behind,
+ // add all X-ray attacks by the rook or queen.
+ if ( bit_is_set(ei.attacked_by(them,ROOK) | ei.attacked_by(them,QUEEN),s)
+ && (squares_behind(us, s) & pos.rooks_and_queens(them)))
+ b3 = b2;
+
+ if ((b2 & pos.pieces_of_color(them)) == EmptyBoardBB)
+ {
+ // There are no enemy pieces in the pawn's path! Are any of the
+ // squares in the pawn's path attacked by the enemy?
+ if (b3 == EmptyBoardBB)
+ // No enemy attacks, huge bonus!
+ ebonus += Value(tr * (b2 == b4 ? 17 : 15));
+ else
+ // OK, there are enemy attacks. Are those squares which are
+ // attacked by the enemy also attacked by us? If yes, big bonus
+ // (but smaller than when there are no enemy attacks), if no,
+ // somewhat smaller bonus.
+ ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8));
+ }
+ else
+ {
+ // There are some enemy pieces in the pawn's path. While this is
+ // sad, we still assign a moderate bonus if all squares in the path
+ // which are either occupied by or attacked by enemy pieces are
+ // also attacked by us.
+ if (((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB)
+ ebonus += Value(tr * 6);
+ }
+ // At last, add a small bonus when there are no *friendly* pieces
+ // in the pawn's path.
+ if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB)
+ ebonus += Value(tr);
+ }
}
- }
- }
- // Rook pawns are a special case: They are sometimes worse, and
- // sometimes better than other passed pawns. It is difficult to find
- // good rules for determining whether they are good or bad. For now,
- // we try the following: Increase the value for rook pawns if the
- // other side has no pieces apart from a knight, and decrease the
- // value if the other side has a rook or queen.
- if(square_file(s) == FILE_A || square_file(s) == FILE_H) {
- if(pos.non_pawn_material(them) == KnightValueMidgame
- && pos.piece_count(them, KNIGHT) == 1)
- ebonus += ebonus / 4;
- else if(pos.rooks_and_queens(them))
- ebonus -= ebonus / 4;
- }
- // Add the scores for this pawn to the middle game and endgame eval.
- ei.mgValue += apply_weight(Sign[us] * mbonus, WeightPassedPawnsMidgame);
- ei.egValue += apply_weight(Sign[us] * ebonus, WeightPassedPawnsEndgame);
- }
+ // If the pawn is supported by a friendly pawn, increase bonus
+ b2 = pos.pawns(us) & neighboring_files_bb(s);
+ if (b2 & rank_bb(s))
+ ebonus += Value(r * 20);
+ else if (pos.pawn_attacks(them, s) & b2)
+ ebonus += Value(r * 12);
+
+ // If the other side has only a king, check whether the pawn is
+ // unstoppable
+ if (pos.non_pawn_material(them) == Value(0))
+ {
+ Square qsq;
+ int d;
+
+ qsq = relative_square(us, make_square(square_file(s), RANK_8));
+ d = square_distance(s, qsq)
+ - square_distance(theirKingSq, qsq)
+ + (us != pos.side_to_move());
+
+ if (d < 0)
+ {
+ int mtg = RANK_8 - relative_rank(us, s);
+ int blockerCount = count_1s_max_15(squares_in_front_of(us,s) & pos.occupied_squares());
+ mtg += blockerCount;
+ d += blockerCount;
+ if (d < 0)
+ {
+ hasUnstoppable[us] = true;
+ movesToGo[us] = Min(movesToGo[us], mtg);
+ }
+ }
+ }
+ // Rook pawns are a special case: They are sometimes worse, and
+ // sometimes better than other passed pawns. It is difficult to find
+ // good rules for determining whether they are good or bad. For now,
+ // we try the following: Increase the value for rook pawns if the
+ // other side has no pieces apart from a knight, and decrease the
+ // value if the other side has a rook or queen.
+ if (square_file(s) == FILE_A || square_file(s) == FILE_H)
+ {
+ if( pos.non_pawn_material(them) <= KnightValueMidgame
+ && pos.piece_count(them, KNIGHT) <= 1)
+ ebonus += ebonus / 4;
+ else if(pos.rooks_and_queens(them))
+ ebonus -= ebonus / 4;
+ }
+
+ // Add the scores for this pawn to the middle game and endgame eval.
+ ei.mgValue += apply_weight(Sign[us] * mbonus, WeightPassedPawnsMidgame);
+ ei.egValue += apply_weight(Sign[us] * ebonus, WeightPassedPawnsEndgame);
+ }
}
// Does either side have an unstoppable passed pawn?
- if(hasUnstoppable[WHITE] && !hasUnstoppable[BLACK])
- ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]);
- else if(hasUnstoppable[BLACK] && !hasUnstoppable[WHITE])
- ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]);
- else if(hasUnstoppable[BLACK] && hasUnstoppable[WHITE]) {
- // Both sides have unstoppable pawns! Try to find out who queens
- // first. We begin by transforming 'movesToGo' to the number of
- // plies until the pawn queens for both sides:
- movesToGo[WHITE] *= 2;
- movesToGo[BLACK] *= 2;
- movesToGo[pos.side_to_move()]--;
-
- // If one side queens at least three plies before the other, that
- // side wins:
- if(movesToGo[WHITE] <= movesToGo[BLACK] - 3)
- ei.egValue += UnstoppablePawnValue - Value(0x40 * (movesToGo[WHITE]/2));
- else if(movesToGo[BLACK] <= movesToGo[WHITE] - 3)
- ei.egValue -= UnstoppablePawnValue - Value(0x40 * (movesToGo[BLACK]/2));
-
- // We could also add some rules about the situation when one side
- // queens exactly one ply before the other: Does the first queen
- // check the opponent's king, or attack the opponent's queening square?
- // This is slightly tricky to get right, because it is possible that
- // the opponent's king has moved somewhere before the first pawn queens.
+ if (hasUnstoppable[WHITE] && !hasUnstoppable[BLACK])
+ ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]);
+ else if (hasUnstoppable[BLACK] && !hasUnstoppable[WHITE])
+ ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]);
+ else if (hasUnstoppable[BLACK] && hasUnstoppable[WHITE])
+ {
+ // Both sides have unstoppable pawns! Try to find out who queens
+ // first. We begin by transforming 'movesToGo' to the number of
+ // plies until the pawn queens for both sides.
+ movesToGo[WHITE] *= 2;
+ movesToGo[BLACK] *= 2;
+ movesToGo[pos.side_to_move()]--;
+
+ // If one side queens at least three plies before the other, that
+ // side wins.
+ if (movesToGo[WHITE] <= movesToGo[BLACK] - 3)
+ ei.egValue += UnstoppablePawnValue - Value(0x40 * (movesToGo[WHITE]/2));
+ else if(movesToGo[BLACK] <= movesToGo[WHITE] - 3)
+ ei.egValue -= UnstoppablePawnValue - Value(0x40 * (movesToGo[BLACK]/2));
+
+ // We could also add some rules about the situation when one side
+ // queens exactly one ply before the other: Does the first queen
+ // check the opponent's king, or attack the opponent's queening square?
+ // This is slightly tricky to get right, because it is possible that
+ // the opponent's king has moved somewhere before the first pawn queens.
}
}
void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
EvalInfo &ei) {
-
assert(square_is_ok(s));
- assert(pos.piece_on(s) == bishop_of_color(us));
+ assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP));
Square b6 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B6 : SQ_G6);
Square b8 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B8 : SQ_G8);
- if ( pos.piece_on(b6) == pawn_of_color(opposite_color(us))
+ if ( pos.piece_on(b6) == piece_of_color_and_type(opposite_color(us), PAWN)
&& pos.see(s, b6) < 0
&& pos.see(s, b8) < 0)
{
void evaluate_trapped_bishop_a1h1(const Position &pos, Square s, Color us,
EvalInfo &ei) {
- Piece pawn = pawn_of_color(us);
+ Piece pawn = piece_of_color_and_type(us, PAWN);
Square b2, b3, c3;
assert(Chess960);
assert(square_is_ok(s));
- assert(pos.piece_on(s) == bishop_of_color(us));
+ assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP));
- if(square_file(s) == FILE_A) {
- b2 = relative_square(us, SQ_B2);
- b3 = relative_square(us, SQ_B3);
- c3 = relative_square(us, SQ_C3);
+ if (square_file(s) == FILE_A)
+ {
+ b2 = relative_square(us, SQ_B2);
+ b3 = relative_square(us, SQ_B3);
+ c3 = relative_square(us, SQ_C3);
}
- else {
- b2 = relative_square(us, SQ_G2);
- b3 = relative_square(us, SQ_G3);
- c3 = relative_square(us, SQ_F3);
+ else
+ {
+ b2 = relative_square(us, SQ_G2);
+ b3 = relative_square(us, SQ_G3);
+ c3 = relative_square(us, SQ_F3);
}
- if(pos.piece_on(b2) == pawn) {
- Value penalty;
+ if (pos.piece_on(b2) == pawn)
+ {
+ Value penalty;
- if(!pos.square_is_empty(b3))
- penalty = 2*TrappedBishopA1H1Penalty;
- else if(pos.piece_on(c3) == pawn)
- penalty = TrappedBishopA1H1Penalty;
- else
- penalty = TrappedBishopA1H1Penalty / 2;
+ if (!pos.square_is_empty(b3))
+ penalty = 2*TrappedBishopA1H1Penalty;
+ else if (pos.piece_on(c3) == pawn)
+ penalty = TrappedBishopA1H1Penalty;
+ else
+ penalty = TrappedBishopA1H1Penalty / 2;
- ei.mgValue -= Sign[us] * penalty;
- ei.egValue -= Sign[us] * penalty;
+ ei.mgValue -= Sign[us] * penalty;
+ ei.egValue -= Sign[us] * penalty;
}
-
}
Color them = opposite_color(us);
// Find the safe squares for our pieces inside the area defined by
- // SpaceMask[us]. A square is unsafe it is attacked by an enemy
+ // SpaceMask[us]. A square is unsafe it is attacked by an enemy
// pawn, or if it is undefended and attacked by an enemy piece.
- Bitboard safeSquares =
- SpaceMask[us] & ~pos.pawns(us) & ~ei.attacked_by(them, PAWN)
- & ~(~ei.attacked_by(us) & ei.attacked_by(them));
+ Bitboard safeSquares = SpaceMask[us]
+ & ~pos.pawns(us)
+ & ~ei.attacked_by(them, PAWN)
+ & ~(~ei.attacked_by(us) & ei.attacked_by(them));
// Find all squares which are at most three squares behind some friendly
// pawn.
Bitboard behindFriendlyPawns = pos.pawns(us);
- if(us == WHITE) {
- behindFriendlyPawns |= (behindFriendlyPawns >> 8);
- behindFriendlyPawns |= (behindFriendlyPawns >> 16);
+ if (us == WHITE)
+ {
+ behindFriendlyPawns |= (behindFriendlyPawns >> 8);
+ behindFriendlyPawns |= (behindFriendlyPawns >> 16);
}
- else {
- behindFriendlyPawns |= (behindFriendlyPawns << 8);
- behindFriendlyPawns |= (behindFriendlyPawns << 16);
+ else
+ {
+ behindFriendlyPawns |= (behindFriendlyPawns << 8);
+ behindFriendlyPawns |= (behindFriendlyPawns << 16);
}
- int space =
- count_1s_max_15(safeSquares)
- + count_1s_max_15(behindFriendlyPawns & safeSquares);
+ int space = count_1s_max_15(safeSquares)
+ + count_1s_max_15(behindFriendlyPawns & safeSquares);
- ei.mgValue += Sign[us] *
- apply_weight(Value(space * ei.mi->space_weight()), WeightSpace);
+ ei.mgValue += Sign[us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace);
}
}
- // 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.
-
- int count_1s_8bit(Bitboard b) {
- return int(BitCount8Bit[b & 0xFF]);
- }
-
-
// compute_weight() computes the value of an evaluation weight, by combining
// an UCI-configurable weight with an internal weight.
int compute_weight(int uciWeight, int internalWeight) {
+
uciWeight = (uciWeight * 0x100) / 100;
return (uciWeight * internalWeight) / 0x100;
}
SafetyTable[i] = Value(peak);
}
}
-
}
projects / stockfish / blobdiff