/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
+ Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "position.h"
#include "thread.h"
+namespace Stockfish {
+
namespace {
#define V Value
#define S(mg, eg) make_score(mg, eg)
// Pawn penalties
- constexpr Score Backward = S( 8, 25);
- constexpr Score Doubled = S(10, 55);
- constexpr Score Isolated = S( 3, 15);
- constexpr Score WeakLever = S( 3, 55);
- constexpr Score WeakUnopposed = S(13, 25);
+ constexpr Score Backward = S( 6, 19);
+ constexpr Score Doubled = S(11, 51);
+ constexpr Score DoubledEarly = S(17, 7);
+ constexpr Score Isolated = S( 1, 20);
+ constexpr Score WeakLever = S( 2, 57);
+ constexpr Score WeakUnopposed = S(15, 18);
// Bonus for blocked pawns at 5th or 6th rank
- constexpr Score BlockedPawn[2] = { S(-15, -3), S(-6, 3) };
+ constexpr Score BlockedPawn[2] = { S(-19, -8), S(-7, 3) };
constexpr Score BlockedStorm[RANK_NB] = {
- S(0, 0), S(0, 0), S(75, 78), S(-8, 16), S(-6, 10), S(-6, 6), S(0, 2)
+ S(0, 0), S(0, 0), S(64, 75), S(-3, 14), S(-12, 19), S(-7, 4), S(-10, 5)
};
// Connected pawn bonus
- constexpr int Connected[RANK_NB] = { 0, 5, 7, 11, 24, 48, 86 };
+ constexpr int Connected[RANK_NB] = { 0, 3, 7, 7, 15, 54, 86 };
// Strength of pawn shelter for our king by [distance from edge][rank].
// RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
- { V( -5), V( 82), V( 92), V( 54), V( 36), V( 22), V( 28) },
- { V(-44), V( 63), V( 33), V(-50), V(-30), V(-12), V( -62) },
- { V(-11), V( 77), V( 22), V( -6), V( 31), V( 8), V( -45) },
- { V(-39), V(-12), V(-29), V(-50), V(-43), V(-68), V(-164) }
+ { V(-2), V(85), V(95), V(53), V(39), V(23), V(25) },
+ { V(-55), V(64), V(32), V(-55), V(-30), V(-11), V(-61) },
+ { V(-11), V(75), V(19), V(-6), V(26), V(9), V(-47) },
+ { V(-41), V(-11), V(-27), V(-58), V(-42), V(-66), V(-163) }
};
// Danger of enemy pawns moving toward our king by [distance from edge][rank].
// is behind our king. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
// on edge, likely blocked by our king.
constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
- { V( 87), V(-288), V(-168), V( 96), V( 47), V( 44), V( 46) },
- { V( 42), V( -25), V( 120), V( 45), V( 34), V( -9), V( 24) },
- { V( -8), V( 51), V( 167), V( 35), V( -4), V(-16), V(-12) },
- { V(-17), V( -13), V( 100), V( 4), V( 9), V(-16), V(-31) }
+ { V(94), V(-280), V(-170), V(90), V(59), V(47), V(53) },
+ { V(43), V(-17), V(128), V(39), V(26), V(-17), V(15) },
+ { V(-9), V(62), V(170), V(34), V(-5), V(-20), V(-11) },
+ { V(-27), V(-19), V(106), V(10), V(2), V(-13), V(-24) }
};
// KingOnFile[semi-open Us][semi-open Them] contains bonuses/penalties
// for king when the king is on a semi-open or open file.
- constexpr Score KingOnFile[2][2] = {{ S(-19,12), S(-6, 7) },
- { S( 0, 2), S( 6,-5) }};
+ constexpr Score KingOnFile[2][2] = {{ S(-18,11), S(-6,-3) },
+ { S( 0, 0), S( 5,-4) }};
#undef S
#undef V
constexpr Color Them = ~Us;
constexpr Direction Up = pawn_push(Us);
+ constexpr Direction Down = -Up;
Bitboard neighbours, stoppers, support, phalanx, opposed;
Bitboard lever, leverPush, blocked;
e->blockedCount += popcount(shift<Up>(ourPawns) & (theirPawns | doubleAttackThem));
// Loop through all pawns of the current color and score each pawn
- while (b) {
- s = pop_lsb(&b);
+ while (b)
+ {
+ s = pop_lsb(b);
assert(pos.piece_on(s) == make_piece(Us, PAWN));
phalanx = neighbours & rank_bb(s);
support = neighbours & rank_bb(s - Up);
+ if (doubled)
+ {
+ // Additional doubled penalty if none of their pawns is fixed
+ if (!(ourPawns & shift<Down>(theirPawns | pawn_attacks_bb<Them>(theirPawns))))
+ score -= DoubledEarly;
+ }
+
// A pawn is backward when it is behind all pawns of the same color on
// the adjacent files and cannot safely advance.
backward = !(neighbours & forward_ranks_bb(Them, s + Up))
else if (backward)
score -= Backward
- + WeakUnopposed * !opposed;
+ + WeakUnopposed * !opposed * bool(~(FileABB | FileHBB) & s);
if (!support)
score -= Doubled * doubled
if (pawns & attacks_bb<KING>(ksq))
minPawnDist = 1;
else while (pawns)
- minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(&pawns)));
+ minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(pawns)));
return shelter - make_score(0, 16 * minPawnDist);
}
template Score Entry::do_king_safety<BLACK>(const Position& pos);
} // namespace Pawns
+
+} // namespace Stockfish
projects / stockfish / blobdiff