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;
// parameters at 100, which looks prettier.
//
// 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;
+ 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;
// Mobility and outposts bonus modified by Joona Kiiski
//
((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] = {
// Bonus for having a mate threat, initialized from UCI options
int MateThreatBonus;
+ // ThreatBonus[][] contains bonus according to which piece type
+ // attacks which one.
+ const Value MidgameThreatBonus[8][8] = {
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0),V(18), V(0),V(37), V(55), V(55), V(0), V(0) }, // KNIGHT attacks
+ { V(0),V(18),V(37), V(0), V(55), V(55), V(0), V(0) }, // BISHOP attacks
+ { V(0), V(9),V(27),V(27), V(0), V(37), V(0), V(0) }, // ROOK attacks
+ { V(0),V(27),V(27),V(27), V(27), V(0), V(0), V(0) }, // QUEEN attacks
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) } // not used
+ };
+
+ const Value EndgameThreatBonus[8][8] = {
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0),V(37), V(0),V(47), V(97), V(97), V(0), V(0) }, // KNIGHT attacks
+ { V(0),V(37),V(47), V(0), V(97), V(97), V(0), V(0) }, // BISHOP attacks
+ { V(0),V(27),V(47),V(47), V(0), V(47), V(0), V(0) }, // ROOK attacks
+ { V(0),V(37),V(37),V(37), V(37), V(0), V(0), V(0) }, // QUEEN attacks
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used
+ { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) } // not used
+ };
+
+ // ThreatedByPawnPenalty[] contains a penalty according to which piece
+ // type is attacked by an enemy pawn.
+ const Value MidgameThreatedByPawnPenalty[8] = {
+ V(0), V(0), V(56), V(56), V(76), V(86), V(0), V(0)
+ };
+
+ const Value EndgameThreatedByPawnPenalty[8] = {
+ V(0), V(0), V(70), V(70), V(99), V(118), V(0), V(0)
+ };
+
// InitKingDanger[] contains bonuses based on the position of the defending
// king.
const int InitKingDanger[64] = {
const int PawnTableSize = 16384;
const int MaterialTableSize = 1024;
- // Array which gives the number of nonzero bits in an 8-bit integer
- uint8_t BitCount8Bit[256];
-
// Function prototypes
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);
+ template<Color Us>
+ void evaluate_threats(const Position& pos, EvalInfo& ei);
+
+ 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 Value apply_weight(Value v, int w);
Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]);
-
- int compute_weight(int uciWeight, int internalWeight);
int weight_option(const std::string& opt, int weight);
void init_safety();
-
}
assert(pos.is_ok());
assert(threadID >= 0 && threadID < THREAD_MAX);
+ assert(!pos.is_check());
memset(&ei, 0, sizeof(EvalInfo));
// Probe the material hash table
ei.mi = MaterialTable[threadID]->get_material_info(pos);
- ei.mgValue += ei.mi->mg_value();
- ei.egValue += ei.mi->eg_value();
+ ei.mgValue += ei.mi->material_value();
+ ei.egValue += ei.mi->material_value();
// If we have a specialized evaluation function for the current material
// configuration, call it and return
ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame);
// 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.kingAttackersCount[WHITE] = count_1s_max_15<HasPopCnt>(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2;
- ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2;
+ 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[WHITE] = count_1s_max_15<HasPopCnt>(b1)/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);
+ if (b2)
+ ei.kingAttackersCount[BLACK] = count_1s_max_15<HasPopCnt>(b2)/2;
- // 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
+ 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 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,
+ // 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);
// 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);
}
}
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);
} // namespace
/// quick_evaluate() does a very approximate evaluation of the current position.
-/// It currently considers only material and piece square table scores. Perhaps
+/// 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) {
}
-/// 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) {
if (!MaterialTable[i])
MaterialTable[i] = new MaterialInfoTable(MaterialTableSize);
}
-
- for (Bitboard b = 0ULL; b < 256ULL; b++)
- {
- assert(count_1s(b) == int(uint8_t(count_1s(b))));
- BitCount8Bit[b] = (uint8_t)count_1s(b);
- }
}
-/// 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) {
+ Color them = opposite_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);
+ WeightSpace = weight_option("Space", WeightSpaceInternal);
+ WeightKingSafety[us] = weight_option("Cowardice", WeightKingSafetyInternal);
+ WeightKingSafety[them] = weight_option("Aggressiveness", WeightKingOppSafetyInternal);
- Color them = opposite_color(us);
-
- WeightKingSafety[us] = weight_option("Cowardice", WeightKingSafetyInternal);
- WeightKingSafety[them] = weight_option("Aggressiveness", WeightKingOppSafetyInternal);
- WeightSpace = weight_option("Space", WeightSpaceInternal);
-
+ // 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];
+ }
init_safety();
}
// 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) {
+ template<PieceType Piece, Color Us, bool HasPopCnt>
+ int evaluate_mobility(Bitboard b, Bitboard mob_area, EvalInfo& ei) {
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
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;
+ ei.attackedBy[Us][Piece] |= b;
// King attacks
- if (b & ei.kingZone[us])
+ if (b & ei.kingZone[Us])
{
- ei.kingAttackersCount[us]++;
- ei.kingAttackersWeight[us] += AttackWeight[Piece];
- Bitboard bb = (b & ei.attackedBy[them][KING]);
+ 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);
+ 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)));
+ int mob = (Piece != QUEEN ? count_1s_max_15<HasPopCnt>(b & mob_area)
+ : count_1s<HasPopCnt>(b & mob_area));
- ei.mgMobility += Sign[us] * MgBonus[Piece][mob];
- ei.egMobility += Sign[us] * EgBonus[Piece][mob];
+ 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 && (pos.attacks_from<PAWN>(s, Them) & pos.pieces(PAWN, Us)))
{
- 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.mgValue += Sign[Us] * bonus;
+ ei.egValue += Sign[Us] * 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 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);
+
+ // Do not include in mobility squares protected by enemy pawns or occupied by our pieces
+ const Bitboard mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us));
+ while ((s = *ptr++) != SQ_NONE)
+ {
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);
+ mob = evaluate_mobility<Piece, Us, HasPopCnt>(b, mob_area, ei);
+
+ // 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.mgValue -= Sign[Us] * MidgameThreatedByPawnPenalty[Piece];
+ ei.egValue -= Sign[Us] * EndgameThreatedByPawnPenalty[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 ( relative_rank(us, s) == RANK_7
- && relative_rank(us, pos.king_square(them)) == RANK_8)
+ 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.mgValue += Sign[Us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus);
+ ei.egValue += Sign[Us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus);
}
}
{
// 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))
+ if (ei.pi->file_is_half_open(Them, f))
{
- ei.mgValue += Sign[us] * RookOpenFileBonus;
- ei.egValue += Sign[us] * RookOpenFileBonus;
+ ei.mgValue += Sign[Us] * RookOpenFileBonus;
+ ei.egValue += Sign[Us] * RookOpenFileBonus;
}
else
{
- ei.mgValue += Sign[us] * RookHalfOpenFileBonus;
- ei.egValue += Sign[us] * RookHalfOpenFileBonus;
+ ei.mgValue += Sign[Us] * RookHalfOpenFileBonus;
+ ei.egValue += Sign[Us] * RookHalfOpenFileBonus;
}
}
// Penalize rooks which are trapped inside a king. Penalize more if
// king has lost right to castle.
- if (mob > 6 || ei.pi->file_is_half_open(us, f))
+ 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.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)))
+ && (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.mgValue -= pos.can_castle(Us)? Sign[Us] * ((TrappedRookPenalty - mob * 16) / 2)
+ : Sign[Us] * (TrappedRookPenalty - mob * 16);
}
}
}
}
- inline Bitboard shiftRowsDown(const Bitboard& b, int num) {
- return b >> (num << 3);
+ // 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;
+ Value mgBonus = Value(0);
+ Value egBonus = Value(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))
+ {
+ mgBonus += MidgameThreatBonus[pt1][pt2];
+ egBonus += EndgameThreatBonus[pt1][pt2];
+ }
+ }
+ ei.mgValue += Sign[Us] * mgBonus;
+ ei.egValue += Sign[Us] * egBonus;
+ }
+
+
+ // 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) {
+
+ evaluate_pieces<KNIGHT, Us, HasPopCnt>(pos, ei);
+ evaluate_pieces<BISHOP, Us, HasPopCnt>(pos, ei);
+ evaluate_pieces<ROOK, Us, HasPopCnt>(pos, ei);
+ evaluate_pieces<QUEEN, Us, HasPopCnt>(pos, ei);
+
+ // 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<bool HasPopCnt>
- void evaluate_king(const Position& p, Color us, EvalInfo& ei) {
+ // evaluate_king<>() assigns bonuses and penalties to a king of a given color
- int shelter = 0, sign = Sign[us];
- Square s = p.king_square(us);
+ template<Color Us, bool HasPopCnt>
+ void evaluate_king(const Position& pos, EvalInfo& ei) {
+
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Square s = pos.king_square(Us);
+ int shelter = 0;
// King shelter
- if (relative_rank(us, s) <= RANK_4)
+ if (relative_rank(Us, s) <= RANK_4)
{
- // 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);
+ shelter = ei.pi->get_king_shelter(pos, Us, s);
+ ei.mgValue += Sign[Us] * Value(shelter);
}
// 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());
+ bool 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);
+ 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;
+ Bitboard occ = pos.occupied_squares(), b, b2;
// Initialize the 'attackUnits' variable, which is used later on as an
// index to the SafetyTable[] array. The initial value is based on the
// 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);
+ 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);
// 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);
+ ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT)
+ | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK);
b &= attackedByOthers;
if (b)
attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1);
// Is there a mate threat?
- if (QueenContactMates && !p.is_check())
+ if (QueenContactMates && !pos.is_check())
{
Bitboard escapeSquares =
- p.piece_attacks<KING>(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
+ pos.attacks_from<KING>(s) & ~pos.pieces_of_color(Us) & ~attackedByOthers;
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++)
+ for (int i = 0; i < pos.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)))
+ 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)))
- ei.mateThreat[them] = make_move(from, to);
+ ei.mateThreat[Them] = make_move(from, to);
}
}
}
// Analyse safe distance checks
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) & ~pos.pieces_of_color(Them) & ~ei.attacked_by(Us);
// 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) & ~pos.pieces_of_color(Them) & ~ei.attacked_by(Us);
// 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) & ~pos.pieces_of_color(Them) & ~ei.attacked_by(Us);
// 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();
+ b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN);
if (b)
- attackUnits += DiscoveredCheckBonus * count_1s_max_15<HasPopCnt>(b) * (sente? 2 : 1);
+ 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
// 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
// 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]);
+ Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[Us]);
- ei.mgValue -= sign * v;
+ ei.mgValue -= Sign[Us] * v;
- if (us == p.side_to_move())
+ if (Us == pos.side_to_move())
ei.futilityMargin += 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));
- 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));
- 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);
- // 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)
+ {
+ Square blockSq = s + pawn_push(Us);
+
+ 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.mgValue += apply_weight(Sign[Us] * mbonus, WeightPassedPawnsMidgame);
+ ei.egValue += apply_weight(Sign[Us] * ebonus, WeightPassedPawnsEndgame);
+
+ } // 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.egValue += 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.egValue += Sign[winnerSide] * (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.egValue += Sign[winnerSide] * (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));
// 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;
// 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.mgValue += Sign[Us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace);
}
}
- // compute_weight() computes the value of an evaluation weight, by combining
+ // weight_option() computes the value of an evaluation weight, by combining
// an UCI-configurable weight with an internal weight.
- int compute_weight(int uciWeight, int internalWeight) {
+ int weight_option(const std::string& opt, int internalWeight) {
+ int uciWeight = get_option_value_int(opt);
uciWeight = (uciWeight * 0x100) / 100;
return (uciWeight * internalWeight) / 0x100;
}
- // helper used in read_weights()
- int weight_option(const std::string& opt, int weight) {
-
- return compute_weight(get_option_value_int(opt), weight);
- }
-
-
// 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)));
}