const int Sign[2] = { 1, -1 };
// Evaluation grain size, must be a power of 2
- const int GrainSize = 4;
+ const int GrainSize = 8;
// Evaluation weights, initialized from UCI options
- int WeightMobilityMidgame, WeightMobilityEndgame;
- int WeightPawnStructureMidgame, WeightPawnStructureEndgame;
- int WeightPassedPawnsMidgame, WeightPassedPawnsEndgame;
- int WeightKingSafety[2];
- int WeightSpace;
+ Score WeightMobility, WeightPawnStructure;
+ Score WeightPassedPawns, WeightSpace;
+ Score WeightKingSafety[2];
// Internal evaluation weights. These are applied on top of the evaluation
// weights read from UCI parameters. The purpose is to be able to change
// parameters at 100, which looks prettier.
//
// Values modified by Joona Kiiski
- const int WeightMobilityMidgameInternal = 248;
- const int WeightMobilityEndgameInternal = 271;
- const int WeightPawnStructureMidgameInternal = 233;
- const int WeightPawnStructureEndgameInternal = 201;
- const int WeightPassedPawnsMidgameInternal = 252;
- const int WeightPassedPawnsEndgameInternal = 259;
- const int WeightKingSafetyInternal = 247;
- const int WeightKingOppSafetyInternal = 259;
- const int WeightSpaceInternal = 46;
+ const Score WeightMobilityInternal = make_score(248, 271);
+ const Score WeightPawnStructureInternal = make_score(233, 201);
+ const Score WeightPassedPawnsInternal = make_score(252, 259);
+ const Score WeightSpaceInternal = make_score( 46, 0);
+ const Score WeightKingSafetyInternal = make_score(247, 0);
+ const Score WeightKingOppSafetyInternal = make_score(259, 0);
// Mobility and outposts bonus modified by Joona Kiiski
- //
- // Visually better to define tables constants
+
typedef Value V;
+ #define S(mg, eg) make_score(mg, eg)
+
+ CACHE_LINE_ALIGNMENT
// Knight mobility bonus in middle game and endgame, indexed by the number
// of attacked squares not occupied by friendly piecess.
- const Value MidgameKnightMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7 8
- V(-38), V(-25),V(-12), V(0), V(12), V(25), V(31), V(38), V(38)
- };
-
- const Value EndgameKnightMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7 8
- V(-33), V(-23),V(-13), V(-3), V(7), V(17), V(22), V(27), V(27)
+ const Score KnightMobilityBonus[16] = {
+ S(-38,-33), S(-25,-23), S(-12,-13), S( 0,-3),
+ S( 12, 7), S( 25, 17), S( 31, 22), S(38, 27), S(38, 27)
};
// Bishop mobility bonus in middle game and endgame, indexed by the number
// 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
- V(-25), V(-11), V(3), V(17), V(31), V(45), V(57), V(65),
- // 8 9 10 11 12 13 14 15
- V( 71), V( 74), V(76), V(78), V(79), V(80), V(81), V(81)
- };
-
- const Value EndgameBishopMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7
- V(-30), V(-16), V(-2), V(12), V(26), V(40), V(52), V(60),
- // 8 9 10 11 12 13 14 15
- V( 65), V( 69), V(71), V(73), V(74), V(75), V(76), V(76)
+ const Score BishopMobilityBonus[16] = {
+ S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12),
+ S( 31, 26), S( 45, 40), S(57, 52), S(65, 60),
+ S( 71, 65), S( 74, 69), S(76, 71), S(78, 73),
+ S( 79, 74), S( 80, 75), S(81, 76), S(81, 76)
};
// Rook mobility bonus in middle game and endgame, indexed by the number
// 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(-20), V(-14), V(-8), V(-2), V(4), V(10), V(14), V(19),
- // 8 9 10 11 12 13 14 15
- V( 23), V( 26), V(27), V(28), V(29), V(30), V(31), V(32)
- };
-
- const Value EndgameRookMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7
- V(-36), V(-19), V(-3), V(13), V(29), V(46), V(62), V(79),
- // 8 9 10 11 12 13 14 15
- V( 95), V(106),V(111),V(114),V(116),V(117),V(118),V(118)
+ const Score RookMobilityBonus[16] = {
+ S(-20,-36), S(-14,-19), S(-8, -3), S(-2, 13),
+ S( 4, 29), S( 10, 46), S(14, 62), S(19, 79),
+ S( 23, 95), S( 26,106), S(27,111), S(28,114),
+ S( 29,116), S( 30,117), S(31,118), S(32,118)
};
// Queen mobility bonus in middle game and endgame, indexed by the number
// of attacked squares not occupied by friendly pieces.
- const Value MidgameQueenMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7
- V(-10), V(-8), V(-6), V(-3), V(-1), V( 1), V( 3), V( 5),
- // 8 9 10 11 12 13 14 15
- V( 8), V(10), V(12), V(15), V(16), V(17), V(18), V(20),
- // 16 17 18 19 20 21 22 23
- V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20),
- // 24 25 26 27 28 29 30 31
- V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20)
+ const Score QueenMobilityBonus[32] = {
+ S(-10,-18), S(-8,-13), S(-6, -7), S(-3, -2), S(-1, 3), S( 1, 8),
+ S( 3, 13), S( 5, 19), S( 8, 23), S(10, 27), S(12, 32), S(15, 34),
+ S( 16, 35), S(17, 35), S(18, 35), S(20, 35), S(20, 35), S(20, 35),
+ S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35),
+ S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35),
+ S( 20, 35), S(20, 35)
};
- const Value EndgameQueenMobilityBonus[] = {
- // 0 1 2 3 4 5 6 7
- V(-18),V(-13), V(-7), V(-2), V( 3), V (8), V(13), V(19),
- // 8 9 10 11 12 13 14 15
- V( 23), V(27), V(32), V(34), V(35), V(35), V(35), V(35),
- // 16 17 18 19 20 21 22 23
- V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35),
- // 24 25 26 27 28 29 30 31
- V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35)
- };
+ // Pointers table to access mobility tables through piece type
+ const Score* MobilityBonus[8] = { 0, 0, KnightMobilityBonus, BishopMobilityBonus,
+ RookMobilityBonus, QueenMobilityBonus, 0, 0 };
// Outpost bonuses for knights and bishops, indexed by square (from white's
// point of view).
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8
};
+ // ThreatBonus[][] contains bonus according to which piece type
+ // attacks which one.
+ #define Z S(0, 0)
+
+ const Score ThreatBonus[8][8] = {
+ { Z, Z, Z, Z, Z, Z, Z, Z }, // not used
+ { Z, S(18,37), Z, S(37,47), S(55,97), S(55,97), Z, Z }, // KNIGHT attacks
+ { Z, S(18,37), S(37,47), Z, S(55,97), S(55,97), Z, Z }, // BISHOP attacks
+ { Z, S( 9,27), S(27,47), S(27,47), Z, S(37,47), Z, Z }, // ROOK attacks
+ { Z, S(27,37), S(27,37), S(27,37), S(27,37), Z, Z, Z }, // QUEEN attacks
+ { Z, Z, Z, Z, Z, Z, Z, Z }, // not used
+ { Z, Z, Z, Z, Z, Z, Z, Z }, // not used
+ { Z, Z, Z, Z, Z, Z, Z, Z } // not used
+ };
+
+ // ThreatedByPawnPenalty[] contains a penalty according to which piece
+ // type is attacked by an enemy pawn.
+ const Score ThreatedByPawnPenalty[8] = {
+ Z, Z, S(56, 70), S(56, 70), S(76, 99), S(86, 118), Z, Z
+ };
+
+ #undef Z
+ #undef S
+
// Bonus for unstoppable passed pawns
const Value UnstoppablePawnValue = Value(0x500);
// Rooks and queens on the 7th rank (modified by Joona Kiiski)
- const Value MidgameRookOn7thBonus = Value(47);
- const Value EndgameRookOn7thBonus = Value(98);
- const Value MidgameQueenOn7thBonus = Value(27);
- const Value EndgameQueenOn7thBonus = Value(54);
+ const Score RookOn7thBonus = make_score(47, 98);
+ const Score QueenOn7thBonus = make_score(27, 54);
// Rooks on open files (modified by Joona Kiiski)
- const Value RookOpenFileBonus = Value(43);
- const Value RookHalfOpenFileBonus = Value(19);
+ const Score RookOpenFileBonus = make_score(43, 43);
+ const Score RookHalfOpenFileBonus = make_score(19, 19);
// Penalty for rooks trapped inside a friendly king which has lost the
// right to castle.
// Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by
// enemy pawns.
- const Value TrappedBishopA7H7Penalty = Value(300);
+ const Score TrappedBishopA7H7Penalty = make_score(300, 300);
// Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black)
const Bitboard MaskA7H7[2] = {
// 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
// happen in Chess960 games.
- const Value TrappedBishopA1H1Penalty = Value(100);
+ const Score TrappedBishopA1H1Penalty = make_score(100, 100);
// Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black)
const Bitboard MaskA1H1[2] = {
((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 SpaceMask[color] contains the area of the board which is considered
+ // by 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] = {
/// 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 and table indexed on piece type
const int QueenAttackWeight = 5;
const int RookAttackWeight = 3;
const int BishopAttackWeight = 2;
const int KnightAttackWeight = 2;
+ const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight };
+
// Bonuses for safe checks, initialized from UCI options
int QueenContactCheckBonus, DiscoveredCheckBonus;
int QueenCheckBonus, RookCheckBonus, BishopCheckBonus, KnightCheckBonus;
// 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};
+ // Pawn and material hash tables, indexed by the current thread id.
+ // Note that they will be initialized at 0 being global variables.
+ MaterialInfoTable* MaterialTable[THREAD_MAX];
+ PawnInfoTable* PawnTable[THREAD_MAX];
// Sizes of pawn and material hash tables
const int PawnTableSize = 16384;
template<bool HasPopCnt>
Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID);
- template<PieceType Piece, bool HasPopCnt>
- void evaluate_pieces(const Position& p, Color us, EvalInfo& ei);
+ template<Color Us, bool HasPopCnt>
+ void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei);
- template<bool HasPopCnt>
- void evaluate_king(const Position& p, Color us, EvalInfo &ei);
+ template<Color Us, bool HasPopCnt>
+ void evaluate_king(const Position& pos, EvalInfo& ei);
- void evaluate_passed_pawns(const Position &pos, EvalInfo &ei);
- void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
- EvalInfo &ei);
- void evaluate_trapped_bishop_a1h1(const Position &pos, Square s, Color us,
- EvalInfo &ei);
- template<bool HasPopCnt>
- 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[]);
+ template<Color Us>
+ void evaluate_threats(const Position& pos, EvalInfo& ei);
- int compute_weight(int uciWeight, int internalWeight);
- int weight_option(const std::string& opt, int weight);
- void init_safety();
+ template<Color Us, bool HasPopCnt>
+ void evaluate_space(const Position& pos, EvalInfo& ei);
+ void evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
+ void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, EvalInfo& ei);
+ void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei);
+ inline Score apply_weight(Score v, Score weight);
+ Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]);
+ Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight);
+ void init_safety();
}
assert(pos.is_ok());
assert(threadID >= 0 && threadID < THREAD_MAX);
+ assert(!pos.is_check());
memset(&ei, 0, sizeof(EvalInfo));
// Initialize by reading the incrementally updated scores included in the
// position object (material + piece square tables)
- ei.mgValue = pos.mg_value();
- ei.egValue = pos.eg_value();
+ ei.value = pos.value();
// Probe the material hash table
ei.mi = MaterialTable[threadID]->get_material_info(pos);
- ei.mgValue += ei.mi->material_value();
- ei.egValue += ei.mi->material_value();
+ ei.value += ei.mi->material_value();
// If we have a specialized evaluation function for the current material
// configuration, call it and return
// Probe the pawn hash table
ei.pi = PawnTable[threadID]->get_pawn_info(pos);
- ei.mgValue += apply_weight(ei.pi->mg_value(), WeightPawnStructureMidgame);
- ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame);
+ ei.value += apply_weight(ei.pi->pawns_value(), WeightPawnStructure);
// Initialize king attack bitboards and king attack zones for both sides
- ei.attackedBy[WHITE][KING] = pos.piece_attacks<KING>(pos.king_square(WHITE));
- ei.attackedBy[BLACK][KING] = pos.piece_attacks<KING>(pos.king_square(BLACK));
+ ei.attackedBy[WHITE][KING] = pos.attacks_from<KING>(pos.king_square(WHITE));
+ ei.attackedBy[BLACK][KING] = pos.attacks_from<KING>(pos.king_square(BLACK));
ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8);
ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8);
// Initialize pawn attack bitboards for both sides
- ei.attackedBy[WHITE][PAWN] = ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB);
- ei.attackedBy[BLACK][PAWN] = ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB);
+ ei.attackedBy[WHITE][PAWN] = ei.pi->pawn_attacks(WHITE);
+ ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK);
Bitboard b1 = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING];
Bitboard b2 = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING];
if (b1)
ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(b2)/2;
// Evaluate pieces
- for (Color c = WHITE; c <= BLACK; c++)
- {
- evaluate_pieces<KNIGHT, HasPopCnt>(pos, c, ei);
- evaluate_pieces<BISHOP, HasPopCnt>(pos, c, ei);
- evaluate_pieces<ROOK, HasPopCnt>(pos, c, ei);
- evaluate_pieces<QUEEN, HasPopCnt>(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];
- }
+ evaluate_pieces_of_color<WHITE, HasPopCnt>(pos, ei);
+ evaluate_pieces_of_color<BLACK, HasPopCnt>(pos, ei);
// 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<HasPopCnt>(pos, c, ei);
+ evaluate_king<WHITE, HasPopCnt>(pos, ei);
+ evaluate_king<BLACK, HasPopCnt>(pos, ei);
- // Evaluate passed pawns. We evaluate passed pawns for both sides at once,
+ // Evaluate tactical threats, we need full attack info
+ evaluate_threats<WHITE>(pos, ei);
+ evaluate_threats<BLACK>(pos, 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
- // both sides have an unstoppable passed pawn.
+ // both sides have an unstoppable passed pawn. To be called after all attacks
+ // are computed, included king.
if (ei.pi->passed_pawns())
evaluate_passed_pawns(pos, ei);
- Phase phase = pos.game_phase();
+ Phase phase = ei.mi->game_phase();
// Middle-game specific evaluation terms
if (phase > PHASE_ENDGAME)
if ( square_file(pos.king_square(WHITE)) >= FILE_E
&& square_file(pos.king_square(BLACK)) <= FILE_D)
- ei.mgValue += ei.pi->queenside_storm_value(WHITE)
- - ei.pi->kingside_storm_value(BLACK);
+ ei.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0);
else if ( square_file(pos.king_square(WHITE)) <= FILE_D
&& square_file(pos.king_square(BLACK)) >= FILE_E)
- ei.mgValue += ei.pi->kingside_storm_value(WHITE)
- - ei.pi->queenside_storm_value(BLACK);
+ ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0);
// Evaluate space for both sides
if (ei.mi->space_weight() > 0)
{
- evaluate_space<HasPopCnt>(pos, WHITE, ei);
- evaluate_space<HasPopCnt>(pos, BLACK, ei);
+ evaluate_space<WHITE, HasPopCnt>(pos, ei);
+ evaluate_space<BLACK, HasPopCnt>(pos, ei);
}
}
// Mobility
- ei.mgValue += apply_weight(ei.mgMobility, WeightMobilityMidgame);
- ei.egValue += apply_weight(ei.egMobility, WeightMobilityEndgame);
+ ei.value += apply_weight(ei.mobility, WeightMobility);
// If we don't already have an unusual scale factor, check for opposite
// colored bishop endgames, and use a lower scale for those
if ( phase < PHASE_MIDGAME
&& pos.opposite_colored_bishops()
- && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0))
- || (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0))))
+ && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && eg_value(ei.value) > Value(0))
+ || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(ei.value) < Value(0))))
{
ScaleFactor sf;
factor[BLACK] = sf;
}
- // Interpolate between the middle game and the endgame score, and
- // return
+ // Interpolate between the middle game and the endgame score
Color stm = pos.side_to_move();
- Value v = Sign[stm] * scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor);
+ Value v = Sign[stm] * scale_by_game_phase(ei.value, phase, factor);
return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v);
}
} // namespace
-/// quick_evaluate() does a very approximate evaluation of the current position.
-/// It currently considers only material and piece square table scores. Perhaps
-/// we should add scores from the pawn and material hash tables?
-
-Value quick_evaluate(const Position &pos) {
-
- assert(pos.is_ok());
-
- static const
- ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL};
-
- Value mgv = pos.mg_value();
- Value egv = pos.eg_value();
- Phase ph = pos.game_phase();
- Color stm = pos.side_to_move();
-
- return Sign[stm] * scale_by_game_phase(mgv, egv, ph, sf);
-}
-
-
-/// init_eval() initializes various tables used by the evaluation function.
+/// init_eval() initializes various tables used by the evaluation function
void init_eval(int threads) {
}
-/// quit_eval() releases heap-allocated memory at program termination.
+/// quit_eval() releases heap-allocated memory at program termination
void quit_eval() {
}
-/// read_weights() reads evaluation weights from the corresponding UCI
-/// parameters.
+/// read_weights() reads evaluation weights from the corresponding UCI parameters
void read_weights(Color us) {
- WeightMobilityMidgame = weight_option("Mobility (Middle Game)", WeightMobilityMidgameInternal);
- WeightMobilityEndgame = weight_option("Mobility (Endgame)", WeightMobilityEndgameInternal);
- WeightPawnStructureMidgame = weight_option("Pawn Structure (Middle Game)", WeightPawnStructureMidgameInternal);
- WeightPawnStructureEndgame = weight_option("Pawn Structure (Endgame)", WeightPawnStructureEndgameInternal);
- WeightPassedPawnsMidgame = weight_option("Passed Pawns (Middle Game)", WeightPassedPawnsMidgameInternal);
- WeightPassedPawnsEndgame = weight_option("Passed Pawns (Endgame)", WeightPassedPawnsEndgameInternal);
-
Color them = opposite_color(us);
- WeightKingSafety[us] = weight_option("Cowardice", WeightKingSafetyInternal);
- WeightKingSafety[them] = weight_option("Aggressiveness", WeightKingOppSafetyInternal);
- // If running in analysis mode, make sure we use symmetrical king safety.
- // We do this by replacing both WeightKingSafety[us] and
- // WeightKingSafety[them] by their average.
- if (get_option_value_bool("UCI_AnalyseMode")) {
+ WeightMobility = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightMobilityInternal);
+ WeightPawnStructure = weight_option("Pawn Structure (Middle Game)", "Pawn Structure (Endgame)", WeightPawnStructureInternal);
+ WeightPassedPawns = weight_option("Passed Pawns (Middle Game)", "Passed Pawns (Endgame)", WeightPassedPawnsInternal);
+ WeightSpace = weight_option("Space", "Space", WeightSpaceInternal);
+ WeightKingSafety[us] = weight_option("Cowardice", "Cowardice", WeightKingSafetyInternal);
+ WeightKingSafety[them] = weight_option("Aggressiveness", "Aggressiveness", WeightKingOppSafetyInternal);
+
+ // If running in analysis mode, make sure we use symmetrical king safety. We do this
+ // by replacing both WeightKingSafety[us] and WeightKingSafety[them] by their average.
+ if (get_option_value_bool("UCI_AnalyseMode"))
+ {
WeightKingSafety[us] = (WeightKingSafety[us] + WeightKingSafety[them]) / 2;
WeightKingSafety[them] = WeightKingSafety[us];
}
-
- WeightSpace = weight_option("Space", WeightSpaceInternal);
-
init_safety();
}
namespace {
- // evaluate_mobility() computes mobility and attacks for every piece
-
- template<PieceType Piece, bool HasPopCnt>
- int evaluate_mobility(const Position& p, const Bitboard& b, Color us, Color them, EvalInfo& ei) {
-
- 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 };
-
- // Update attack info
- ei.attackedBy[us][Piece] |= b;
-
- // King attacks
- if (b & ei.kingZone[us])
- {
- ei.kingAttackersCount[us]++;
- ei.kingAttackersWeight[us] += AttackWeight[Piece];
- Bitboard bb = (b & ei.attackedBy[them][KING]);
- if (bb)
- ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15<HasPopCnt>(bb);
- }
-
- // Remove squares protected by enemy pawns
- Bitboard bb = (b & ~ei.attackedBy[them][PAWN]);
-
- // Mobility
- int mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(bb & ~p.pieces_of_color(us))
- : count_1s<HasPopCnt>(bb & ~p.pieces_of_color(us)));
-
- ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
- ei.egMobility += Sign[us] * EgBonus[Piece][mob];
- return mob;
- }
-
-
// evaluate_outposts() evaluates bishop and knight outposts squares
- template<PieceType Piece>
- void evaluate_outposts(const Position& p, Color us, Color them, EvalInfo& ei, Square s) {
+ template<PieceType Piece, Color Us>
+ void evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) {
+
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
// Initial bonus based on square
- Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(us, s)]
- : KnightOutpostBonus[relative_square(us, s)]);
+ Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(Us, s)]
+ : KnightOutpostBonus[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 (bonus && (p.pawn_attacks(them, s) & p.pawns(us)))
+ if (bonus && bit_is_set(ei.attackedBy[Us][PAWN], s))
{
- if ( p.knights(them) == EmptyBoardBB
- && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB)
+ if ( pos.pieces(KNIGHT, Them) == EmptyBoardBB
+ && (SquaresByColorBB[square_color(s)] & pos.pieces(BISHOP, Them)) == EmptyBoardBB)
bonus += bonus + bonus / 2;
else
bonus += bonus / 2;
}
- ei.mgValue += Sign[us] * bonus;
- ei.egValue += Sign[us] * bonus;
+ ei.value += Sign[Us] * make_score(bonus, bonus);
}
- // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given
- // color.
+ // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given color
- template<PieceType Piece, bool HasPopCnt>
- void evaluate_pieces(const Position& pos, Color us, EvalInfo& ei) {
+ template<PieceType Piece, Color Us, bool HasPopCnt>
+ void evaluate_pieces(const Position& pos, EvalInfo& ei, Bitboard no_mob_area) {
Bitboard b;
Square s, ksq;
int mob;
File f;
- Color them = opposite_color(us);
- for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++)
- {
- s = pos.piece_list(us, Piece, i);
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Square* ptr = pos.piece_list_begin(Us, Piece);
+ while ((s = *ptr++) != SQ_NONE)
+ {
+ // Find attacked squares, including x-ray attacks for bishops and rooks
if (Piece == KNIGHT || Piece == QUEEN)
- b = pos.
piece_attacks<Piece>(s);
+ b = pos.
attacks_from<Piece>(s);
else if (Piece == BISHOP)
- b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.queens(us));
+ b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(QUEEN, Us));
else if (Piece == ROOK)
- b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us));
+ b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(ROOK, QUEEN, Us));
else
assert(false);
- // Attacks and mobility
- mob = evaluate_mobility<Piece, HasPopCnt>(pos, b, us, them, ei);
+ // Update attack info
+ ei.attackedBy[Us][Piece] |= b;
+
+ // King attacks
+ if (b & ei.kingZone[Us])
+ {
+ ei.kingAttackersCount[Us]++;
+ ei.kingAttackersWeight[Us] += AttackWeight[Piece];
+ Bitboard bb = (b & ei.attackedBy[Them][KING]);
+ if (bb)
+ ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15<HasPopCnt>(bb);
+ }
+
+ // Mobility
+ mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(b & no_mob_area)
+ : count_1s<HasPopCnt>(b & no_mob_area));
+
+ ei.mobility += Sign[Us] * MobilityBonus[Piece][mob];
+
+ // Decrease score if we are attacked by an enemy pawn. Remaining part
+ // of threat evaluation must be done later when we have full attack info.
+ if (bit_is_set(ei.attackedBy[Them][PAWN], s))
+ ei.value -= Sign[Us] * ThreatedByPawnPenalty[Piece];
// Bishop and knight outposts squares
- if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, them))
- evaluate_outposts<Piece>(pos, us, them, ei, s);
+ if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Them))
+ evaluate_outposts<Piece, Us>(pos, ei, s);
// 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 (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);
+ if (Chess960 && bit_is_set(MaskA1H1[Us], s))
+ evaluate_trapped_bishop_a1h1(pos, s, Us, ei);
}
- if (Piece == ROOK || Piece == QUEEN)
+ // Queen or rook on 7th rank
+ if ( (Piece == ROOK || Piece == QUEEN)
+ && relative_rank(Us, s) == RANK_7
+ && relative_rank(Us, pos.king_square(Them)) == RANK_8)
{
- // Queen or rook on 7th rank
- 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);
- }
+ ei.value += Sign[Us] * (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
}
// Special extra evaluation for rooks
{
// 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(Us, f))
{
- if (ei.pi->file_is_half_open(them, f))
- {
- ei.mgValue += Sign[us] * RookOpenFileBonus;
- ei.egValue += Sign[us] * RookOpenFileBonus;
- }
+ if (ei.pi->file_is_half_open(Them, f))
+ ei.value += Sign[Us] * RookOpenFileBonus;
else
- {
- ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
- ei.egValue += Sign[us] * RookHalfOpenFileBonus;
- }
+ ei.value += 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))
+ 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)))
+ && (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);
+ if (!ei.pi->has_open_file_to_right(Us, square_file(ksq)))
+ ei.value -= Sign[Us] * make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
+ : (TrappedRookPenalty - mob * 16), 0);
}
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)))
+ && 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 (!ei.pi->has_open_file_to_left(Us, square_file(ksq)))
+ ei.value -= Sign[Us] * make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
+ : (TrappedRookPenalty - mob * 16), 0);
}
}
}
}
- // evaluate_king<>() assigns bonuses and penalties to a king of a given color.
+ // evaluate_threats<>() assigns bonuses according to the type of attacking piece
+ // and the type of attacked one.
+
+ template<Color Us>
+ void evaluate_threats(const Position& pos, EvalInfo& ei) {
+
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+
+ Bitboard b;
+ Score bonus = make_score(0, 0);
+
+ // Enemy pieces not defended by a pawn and under our attack
+ Bitboard weakEnemies = pos.pieces_of_color(Them)
+ & ~ei.attackedBy[Them][PAWN]
+ & ei.attackedBy[Us][0];
+ if (!weakEnemies)
+ return;
+
+ // Add bonus according to type of attacked enemy pieces and to the
+ // type of attacking piece, from knights to queens. Kings are not
+ // considered because are already special handled in king evaluation.
+ for (PieceType pt1 = KNIGHT; pt1 < KING; pt1++)
+ {
+ b = ei.attackedBy[Us][pt1] & weakEnemies;
+ if (b)
+ for (PieceType pt2 = PAWN; pt2 < KING; pt2++)
+ if (b & pos.pieces(pt2))
+ bonus += ThreatBonus[pt1][pt2];
+ }
+ ei.value += Sign[Us] * bonus;
+ }
- template<bool HasPopCnt>
- void evaluate_king(const Position& p, Color us, EvalInfo& ei) {
- int shelter = 0, sign = Sign[us];
- Square s = p.king_square(us);
+ // evaluate_pieces_of_color<>() assigns bonuses and penalties to all the
+ // pieces of a given color.
+
+ template<Color Us, bool HasPopCnt>
+ void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei) {
+
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+
+ // Do not include in mobility squares protected by enemy pawns or occupied by our pieces
+ const Bitboard no_mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us));
+
+ evaluate_pieces<KNIGHT, Us, HasPopCnt>(pos, ei, no_mob_area);
+ evaluate_pieces<BISHOP, Us, HasPopCnt>(pos, ei, no_mob_area);
+ evaluate_pieces<ROOK, Us, HasPopCnt>(pos, ei, no_mob_area);
+ evaluate_pieces<QUEEN, Us, HasPopCnt>(pos, ei, no_mob_area);
+
+ // Sum up all attacked squares
+ ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
+ | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
+ | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING];
+ }
+
+
+ // evaluate_king<>() assigns bonuses and penalties to a king of a given color
+
+ template<Color Us, bool HasPopCnt>
+ void evaluate_king(const Position& pos, EvalInfo& ei) {
+
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+
+ Bitboard undefended, attackedByOthers, escapeSquares, occ, b, b2, safe;
+ Square from, to;
+ bool sente;
+ int attackUnits, count, shelter = 0;
+ const Square s = pos.king_square(Us);
// King shelter
- if (relative_rank(us, s) <= RANK_4)
+ if (relative_rank(Us, s) <= RANK_4)
{
- shelter = ei.pi->get_king_shelter(p, us, s);
- ei.mgValue += sign * Value(shelter);
+ shelter = ei.pi->get_king_shelter(pos, Us, s);
+ ei.value += Sign[Us] * make_score(shelter, 0);
}
// King safety. This is quite complicated, and is almost certainly far
// from optimally tuned.
- Color them = opposite_color(us);
-
- if ( p.piece_count(them, QUEEN) >= 1
- && ei.kingAttackersCount[them] >= 2
- && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame
- && ei.kingAdjacentZoneAttacksCount[them])
+ if ( pos.piece_count(Them, QUEEN) >= 1
+ && ei.kingAttackersCount[Them] >= 2
+ && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame
+ && ei.kingAdjacentZoneAttacksCount[Them])
{
// Is it the attackers turn to move?
- bool sente = (them == p.side_to_move());
+ sente = (Them == pos.side_to_move());
// Find the attacked squares around the king which has no defenders
// apart from the king itself
- Bitboard undefended =
- ei.attacked_by(them) & ~ei.attacked_by(us, PAWN)
- & ~ei.attacked_by(us, KNIGHT) & ~ei.attacked_by(us, BISHOP)
- & ~ei.attacked_by(us, ROOK) & ~ei.attacked_by(us, QUEEN)
- & ei.attacked_by(us, KING);
-
- Bitboard occ = p.occupied_squares(), b, b2;
+ undefended = ei.attacked_by(Them) & ei.attacked_by(Us, KING);
+ undefended &= ~( ei.attacked_by(Us, PAWN) | ei.attacked_by(Us, KNIGHT)
+ | ei.attacked_by(Us, BISHOP) | ei.attacked_by(Us, ROOK)
+ | ei.attacked_by(Us, QUEEN));
// Initialize the 'attackUnits' variable, which is used later on as an
- // index to the SafetyTable[] array. The initial value is based on the
+ // index to the SafetyTable[] array. The initial value is based on the
// number and types of the attacking pieces, the number of attacked and
// undefended squares around the king, the square of the king, and the
// quality of the pawn shelter.
- int attackUnits =
- Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25)
- + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15<HasPopCnt>(undefended)) * 3
- + InitKingDanger[relative_square(us, s)] - (shelter >> 5);
+ attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
+ + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15<HasPopCnt>(undefended))
+ + InitKingDanger[relative_square(Us, s)]
+ - (shelter >> 5);
// Analyse safe queen contact checks
- b = undefended & ei.attacked_by(them, QUEEN) & ~p.pieces_of_color(them);
+ b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them);
if (b)
{
- Bitboard attackedByOthers =
- ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT)
- | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK);
+ attackedByOthers = ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT)
+ | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK);
b &= attackedByOthers;
+
+ // Squares attacked by the queen and supported by another enemy piece and
+ // not defended by other pieces but our king.
if (b)
{
- // The bitboard b now contains the squares available for safe queen
- // contact checks.
- int count = count_1s_max_15<HasPopCnt>(b);
- attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1);
-
- // Is there a mate threat?
- if (QueenContactMates && !p.is_check())
- {
- Bitboard escapeSquares =
- p.piece_attacks<KING>(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
-
- while (b)
+ // The bitboard b now contains the squares available for safe queen
+ // contact checks.
+ count = count_1s_max_15<HasPopCnt>(b);
+ attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1);
+
+ // Is there a mate threat?
+ if (QueenContactMates && !pos.is_check())
{
- Square from, to = pop_1st_bit(&b);
- if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[s])))
+ escapeSquares = pos.attacks_from<KING>(s) & ~pos.pieces_of_color(Us) & ~attackedByOthers;
+ occ = pos.occupied_squares();
+ while (b)
{
- // We have a mate, unless the queen is pinned or there
- // is an X-ray attack through the queen.
- for (int i = 0; i < p.piece_count(them, QUEEN); i++)
- {
- from = p.piece_list(them, QUEEN, i);
- 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))
- && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & p.bishops_and_queens(us)))
+ to = pop_1st_bit(&b);
- ei.mateThreat[them] = make_move(from, to);
+ // Do we have escape squares from queen contact check attack ?
+ if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[s])))
+ {
+ // We have a mate, unless the queen is pinned or there
+ // is an X-ray attack through the queen.
+ for (int i = 0; i < pos.piece_count(Them, QUEEN); i++)
+ {
+ from = pos.piece_list(Them, QUEEN, i);
+ if ( bit_is_set(pos.attacks_from<QUEEN>(from), to)
+ && !bit_is_set(pos.pinned_pieces(Them), from)
+ && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(ROOK, QUEEN, Us))
+ && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(BISHOP, QUEEN, Us)))
+
+ // Set the mate threat move
+ ei.mateThreat[Them] = make_move(from, to);
+ }
}
}
}
- }
}
}
// Analyse safe distance checks
+ safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us));
+
if (QueenCheckBonus > 0 || RookCheckBonus > 0)
{
- b = p.piece_attacks<ROOK>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+ b = pos.attacks_from<ROOK>(s) & safe;
// Queen checks
- b2 = b & ei.attacked_by(them, QUEEN);
- if( b2)
+ b2 = b & ei.attacked_by(Them, QUEEN);
+ if (b2)
attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b2);
// Rook checks
- b2 = b & ei.attacked_by(them, ROOK);
+ b2 = b & ei.attacked_by(Them, ROOK);
if (b2)
attackUnits += RookCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
if (QueenCheckBonus > 0 || BishopCheckBonus > 0)
{
- b = p.piece_attacks<BISHOP>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+ b = pos.attacks_from<BISHOP>(s) & safe;
// Queen checks
- b2 = b & ei.attacked_by(them, QUEEN);
+ b2 = b & ei.attacked_by(Them, QUEEN);
if (b2)
attackUnits += QueenCheckBonus * count_1s_max_15<HasPopCnt>(b2);
// Bishop checks
- b2 = b & ei.attacked_by(them, BISHOP);
+ b2 = b & ei.attacked_by(Them, BISHOP);
if (b2)
attackUnits += BishopCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
if (KnightCheckBonus > 0)
{
- b = p.piece_attacks<KNIGHT>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+ b = pos.attacks_from<KNIGHT>(s) & safe;
// Knight checks
- b2 = b & ei.attacked_by(them, KNIGHT);
+ b2 = b & ei.attacked_by(Them, KNIGHT);
if (b2)
attackUnits += KnightCheckBonus * count_1s_max_15<HasPopCnt>(b2);
}
// adding pawns later).
if (DiscoveredCheckBonus)
{
- b = p.discovered_check_candidates(them) & ~p.pawns();
- if (b)
- attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente? 2 : 1);
+ b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN);
+ if (b)
+ attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente ? 2 : 1);
}
- // Has a mate threat been found? We don't do anything here if the
+ // Has a mate threat been found? We don't do anything here if the
// side with the mating move is the side to move, because in that
// case the mating side will get a huge bonus at the end of the main
// evaluation function instead.
- if (ei.mateThreat[them] != MOVE_NONE)
+ if (ei.mateThreat[Them] != MOVE_NONE)
attackUnits += MateThreatBonus;
// Ensure that attackUnits is between 0 and 99, in order to avoid array
- // out of bounds errors:
- if (attackUnits < 0)
- attackUnits = 0;
-
- if (attackUnits >= 100)
- attackUnits = 99;
+ // out of bounds errors.
+ attackUnits = Min(99, Max(0, attackUnits));
// Finally, extract the king safety score from the SafetyTable[] array.
- // Add the score to the evaluation, and also to ei.futilityMargin. The
+ // Add the score to the evaluation, and also to ei.futilityMargin. The
// reason for adding the king safety score to the futility margin is
// that the king safety scores can sometimes be very big, and that
// capturing a single attacking piece can therefore result in a score
// change far bigger than the value of the captured piece.
- Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[us]);
-
- ei.mgValue -= sign * v;
-
- if (us == p.side_to_move())
- ei.futilityMargin += v;
+ Score v = apply_weight(make_score(SafetyTable[attackUnits], 0), WeightKingSafety[Us]);
+ ei.value -= Sign[Us] * v;
+ ei.futilityMargin[Us] += mg_value(v);
}
}
- // evaluate_passed_pawns() evaluates the passed pawns for both sides.
+ // evaluate_passed_pawns() evaluates the passed pawns of the given color
+
+ template<Color Us>
+ void evaluate_passed_pawns_of_color(const Position& pos, int movesToGo[], Square pawnToGo[], EvalInfo& ei) {
- void evaluate_passed_pawns(const Position &pos, EvalInfo &ei) {
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
- bool hasUnstoppable[2] = {false, false};
- int movesToGo[2] = {100, 100};
+ Bitboard b2, b3, b4;
+ Square ourKingSq = pos.king_square(Us);
+ Square theirKingSq = pos.king_square(Them);
+ Bitboard b = ei.pi->passed_pawns() & pos.pieces(PAWN, Us);
- for (Color us = WHITE; us <= BLACK; us++)
+ while (b)
{
- 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;
+ Square s = pop_1st_bit(&b);
- 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));
- assert(pos.piece_on(s) == piece_of_color_and_type(us, PAWN));
- assert(pos.pawn_is_passed(us, s));
+ // Base bonus based on rank
+ Value mbonus = Value(20 * tr);
+ Value ebonus = Value(10 + r * r * 10);
- int r = int(relative_rank(us, s) - RANK_2);
- int tr = Max(0, r * (r - 1));
- Square blockSq = s + pawn_push(us);
+ // Adjust bonus based on king proximity
+ if (tr)
+ {
+ Square blockSq = s + pawn_push(Us);
- // Base bonus based on rank
- Value mbonus = Value(20 * tr);
- Value ebonus = Value(10 + r * r * 10);
+ 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);
- // Adjust bonus based on king proximity
- if (tr != 0)
+ // If the pawn is free to advance, increase bonus
+ if (pos.square_is_empty(blockSq))
{
- 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);
+ // There are no enemy pawns in the pawn's path
+ b2 = squares_in_front_of(Us, s);
- // 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;
-
- // Squares attacked or occupied by enemy pieces
- b3 |= (b2 & pos.pieces_of_color(them));
-
- // There are no enemy pawns in the pawn's path
- assert((b2 & pos.pieces_of_color_and_type(them, PAWN)) == EmptyBoardBB);
-
- // Are any of the squares in the pawn's path attacked or occupied by the enemy?
- if (b3 == EmptyBoardBB)
- // No enemy attacks or pieces, huge bonus!
- ebonus += Value(tr * (b2 == b4 ? 17 : 15));
- else
- // OK, there are enemy attacks or pieces (but not pawns). 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));
-
- // 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);
- }
- }
+ assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB);
- // 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);
+ // Squares attacked by us
+ b4 = b2 & ei.attacked_by(Us);
- // 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;
+ // Squares attacked or occupied by enemy pieces
+ b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them));
- 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 there is an enemy rook or queen attacking the pawn from behind,
+ // add all X-ray attacks by the rook or queen.
+ if ( (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them))
+ && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from<QUEEN>(s)))
+ b3 = b2;
- 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);
- }
- }
+ // Are any of the squares in the pawn's path attacked or occupied by the enemy?
+ if (b3 == EmptyBoardBB)
+ // No enemy attacks or pieces, huge bonus!
+ // Even bigger if we protect the pawn's path
+ ebonus += Value(tr * (b2 == b4 ? 17 : 15));
+ else
+ // OK, there are enemy attacks or pieces (but not pawns). 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));
+
+ // 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)
+ } // tr != 0
+
+ // If the pawn is supported by a friendly pawn, increase bonus
+ b2 = pos.pieces(PAWN, Us) & neighboring_files_bb(s);
+ if (b2 & rank_bb(s))
+ ebonus += Value(r * 20);
+ else if (pos.attacks_from<PAWN>(s, Them) & 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)
{
- 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;
+ 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 && (!movesToGo[Us] || movesToGo[Us] > mtg))
+ {
+ movesToGo[Us] = mtg;
+ pawnToGo[Us] = s;
+ }
}
+ }
- // 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);
+ // 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.pieces(ROOK, QUEEN, Them))
+ ebonus -= ebonus / 4;
}
- }
- // 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])
+ // Add the scores for this pawn to the middle game and endgame eval.
+ ei.value += Sign[Us] * apply_weight(make_score(mbonus, ebonus), WeightPassedPawns);
+
+ } // while
+ }
+
+
+ // evaluate_passed_pawns() evaluates the passed pawns for both sides
+
+ void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) {
+
+ int movesToGo[2] = {0, 0};
+ Square pawnToGo[2] = {SQ_NONE, SQ_NONE};
+
+ // Evaluate pawns for each color
+ evaluate_passed_pawns_of_color<WHITE>(pos, movesToGo, pawnToGo, ei);
+ evaluate_passed_pawns_of_color<BLACK>(pos, movesToGo, pawnToGo, ei);
+
+ // Neither side has an unstoppable passed pawn?
+ if (!(movesToGo[WHITE] | movesToGo[BLACK]))
+ return;
+
+ // Does only one side have an unstoppable passed pawn?
+ if (!movesToGo[WHITE] || !movesToGo[BLACK])
{
- // Both sides have unstoppable pawns! Try to find out who queens
+ Color winnerSide = movesToGo[WHITE] ? WHITE : BLACK;
+ ei.value += make_score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * movesToGo[winnerSide])));
+ }
+ else
+ { // 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.
+ Color winnerSide = movesToGo[WHITE] < movesToGo[BLACK] ? WHITE : BLACK;
+ Color loserSide = opposite_color(winnerSide);
+
+ // If one side queens at least three plies before the other, that side wins
+ if (movesToGo[winnerSide] <= movesToGo[loserSide] - 3)
+ ei.value += Sign[winnerSide] * make_score(0, UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2)));
+
+ // If one side queens one ply before the other and checks the king or attacks
+ // the undefended opponent's queening square, that side wins. To avoid cases
+ // where the opponent's king could move somewhere before first pawn queens we
+ // consider only free paths to queen for both pawns.
+ else if ( !(squares_in_front_of(WHITE, pawnToGo[WHITE]) & pos.occupied_squares())
+ && !(squares_in_front_of(BLACK, pawnToGo[BLACK]) & pos.occupied_squares()))
+ {
+ assert(movesToGo[loserSide] - movesToGo[winnerSide] == 1);
+
+ Square winnerQSq = relative_square(winnerSide, make_square(square_file(pawnToGo[winnerSide]), RANK_8));
+ Square loserQSq = relative_square(loserSide, make_square(square_file(pawnToGo[loserSide]), RANK_8));
+
+ Bitboard b = pos.occupied_squares();
+ clear_bit(&b, pawnToGo[winnerSide]);
+ clear_bit(&b, pawnToGo[loserSide]);
+ b = queen_attacks_bb(winnerQSq, b);
+
+ if ( (b & pos.pieces(KING, loserSide))
+ ||(bit_is_set(b, loserQSq) && !bit_is_set(ei.attacked_by(loserSide), loserQSq)))
+ ei.value += Sign[winnerSide] * make_score(0, UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2)));
+ }
}
}
// (a2/h2 for black) is trapped by enemy pawns, and assigns a penalty
// if it is.
- void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us,
- EvalInfo &ei) {
+ void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, EvalInfo &ei) {
+
assert(square_is_ok(s));
assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP));
&& pos.see(s, b6) < 0
&& pos.see(s, b8) < 0)
{
- ei.mgValue -= Sign[us] * TrappedBishopA7H7Penalty;
- ei.egValue -= Sign[us] * TrappedBishopA7H7Penalty;
+ ei.value -= Sign[us] * TrappedBishopA7H7Penalty;
}
}
// evaluate_trapped_bishop_a1h1() determines whether a bishop on a1/h1
// (a8/h8 for black) is trapped by a friendly pawn on b2/g2 (b7/g7 for
- // black), and assigns a penalty if it is. This pattern can obviously
+ // black), and assigns a penalty if it is. This pattern can obviously
// only occur in Chess960 games.
- void evaluate_trapped_bishop_a1h1(const Position &pos, Square s, Color us,
- EvalInfo &ei) {
+ void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei) {
+
Piece pawn = piece_of_color_and_type(us, PAWN);
Square b2, b3, c3;
if (pos.piece_on(b2) == pawn)
{
- Value penalty;
+ Score penalty;
if (!pos.square_is_empty(b3))
- penalty = 2*TrappedBishopA1H1Penalty;
+ 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.value -= Sign[us] * penalty;
}
}
// squares one, two or three squares behind a friendly pawn are counted
// twice. Finally, the space bonus is scaled by a weight taken from the
// material hash table.
- template<bool HasPopCnt>
- void evaluate_space(const Position &pos, Color us, EvalInfo &ei) {
+ template<Color Us, bool HasPopCnt>
+ void evaluate_space(const Position& pos, EvalInfo& ei) {
- Color them = opposite_color(us);
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
// 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 if 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.pieces(PAWN, 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);
- }
- else
- {
- behindFriendlyPawns |= (behindFriendlyPawns << 8);
- behindFriendlyPawns |= (behindFriendlyPawns << 16);
- }
+ Bitboard behindFriendlyPawns = pos.pieces(PAWN, Us);
+ behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 8 : behindFriendlyPawns << 8);
+ behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 16 : behindFriendlyPawns << 16);
int space = count_1s_max_15<HasPopCnt>(safeSquares)
+ count_1s_max_15<HasPopCnt>(behindFriendlyPawns & safeSquares);
- ei.mgValue += Sign[us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace);
+ ei.value += Sign[Us] * apply_weight(make_score(space * ei.mi->space_weight(), 0), WeightSpace);
}
- // apply_weight() applies an evaluation weight to a value
+ // apply_weight() applies an evaluation weight to a value trying to prevent overflow
- inline Value apply_weight(Value v, int w) {
- return (v*w) / 0x100;
+ inline Score apply_weight(Score v, Score w) {
+ return make_score((int(mg_value(v)) * mg_value(w)) / 0x100, (int(eg_value(v)) * eg_value(w)) / 0x100);
}
// 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[]) {
+ Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]) {
- assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE);
- assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE);
+ assert(mg_value(v) > -VALUE_INFINITE && mg_value(v) < VALUE_INFINITE);
+ assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE);
assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME);
- ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]);
+ Value ev = apply_scale_factor(eg_value(v), sf[(eg_value(v) > Value(0) ? WHITE : BLACK)]);
- Value result = Value(int((mv * ph + ev * (128 - ph)) / 128));
- return Value(int(result) & ~(GrainSize - 1));
+ int result = (mg_value(v) * ph + ev * (128 - ph)) / 128;
+ return Value(result & ~(GrainSize - 1));
}
- // 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) {
+ // weight_option() computes the value of an evaluation weight, by combining
+ // two UCI-configurable weights (midgame and endgame) with an internal weight.
- uciWeight = (uciWeight * 0x100) / 100;
- return (uciWeight * internalWeight) / 0x100;
- }
+ Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) {
+ Score uciWeight = make_score(get_option_value_int(mgOpt), get_option_value_int(egOpt));
- // helper used in read_weights()
- int weight_option(const std::string& opt, int weight) {
+ // Convert to integer to prevent overflow
+ int mg = mg_value(uciWeight);
+ int eg = eg_value(uciWeight);
- return compute_weight(get_option_value_int(opt), weight);
+ mg = (mg * 0x100) / 100;
+ eg = (eg * 0x100) / 100;
+ mg = (mg * mg_value(internalWeight)) / 0x100;
+ eg = (eg * eg_value(internalWeight)) / 0x100;
+ return make_score(mg, eg);
}
-
// init_safety() initizes the king safety evaluation, based on UCI
// parameters. It is called from read_weights().
{
if (i < b)
SafetyTable[i] = Value(0);
- else if(quad)
+ else if (quad)
SafetyTable[i] = Value((int)(a * (i - b) * (i - b)));
- else if(linear)
+ else if (linear)
SafetyTable[i] = Value((int)(100 * a * (i - b)));
}
projects / stockfish / blobdiff