#include "evaluate.h"
#include "material.h"
#include "pawns.h"
-
-std::atomic<Score> Eval::Contempt;
+#include "thread.h"
namespace Trace {
constexpr Value SpaceThreshold = Value(12222);
// KingAttackWeights[PieceType] contains king attack weights by piece type
- constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 };
+ constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 77, 55, 44, 10 };
// Penalties for enemy's safe checks
constexpr int QueenSafeCheck = 780;
S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(36, 38)
};
- // ThreatByKing[on one/on many] contains bonuses for king attacks on
- // pawns or pieces which are not pawn-defended.
- constexpr Score ThreatByKing[] = { S(3, 65), S(9, 145) };
-
// PassedRank[Rank] contains a bonus according to the rank of a passed pawn
constexpr Score PassedRank[RANK_NB] = {
- S(0, 0), S(5, 7), S(5, 13), S(32, 42), S(70, 70), S(172, 170), S(217, 269)
+ S(0, 0), S(5, 18), S(12, 23), S(10, 31), S(57, 62), S(163, 167), S(271, 250)
};
// PassedFile[File] contains a bonus according to the file of a passed pawn
constexpr Score PassedFile[FILE_NB] = {
- S( 9, 10), S(2, 10), S(1, -8), S(-20,-12),
- S(-20,-12), S(1, -8), S(2, 10), S( 9, 10)
+ S( -1, 7), S( 0, 9), S(-9, -8), S(-30,-14),
+ S(-30,-14), S(-9, -8), S( 0, 9), S( -1, 7)
};
// PassedDanger[Rank] contains a term to weight the passed score
- constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 2, 7, 12, 19 };
+ constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 3, 7, 11, 20 };
- // KingProtector[PieceType-2] contains a penalty according to distance from king
- constexpr Score KingProtector[] = { S(3, 5), S(4, 3), S(3, 0), S(1, -1) };
+ // KingProtector[knight/bishop] contains a penalty according to distance from king
+ constexpr Score KingProtector[] = { S(5, 6), S(6, 5) };
// Assorted bonuses and penalties
- constexpr Score BishopPawns = S( 8, 12);
- constexpr Score CloseEnemies = S( 7, 0);
+ constexpr Score BishopPawns = S( 3, 7);
+ constexpr Score CloseEnemies = S( 6, 0);
constexpr Score Connectivity = S( 3, 1);
constexpr Score CorneredBishop = S( 50, 50);
constexpr Score Hanging = S( 52, 30);
- constexpr Score HinderPassedPawn = S( 8, 1);
+ constexpr Score HinderPassedPawn = S( 4, 0);
constexpr Score KnightOnQueen = S( 21, 11);
constexpr Score LongDiagonalBishop = S( 22, 0);
constexpr Score MinorBehindPawn = S( 16, 0);
+ constexpr Score Overload = S( 10, 5);
constexpr Score PawnlessFlank = S( 20, 80);
constexpr Score RookOnPawn = S( 8, 24);
constexpr Score SliderOnQueen = S( 42, 21);
- constexpr Score ThreatByPawnPush = S( 47, 26);
+ constexpr Score ThreatByKing = S( 23, 76);
+ constexpr Score ThreatByPawnPush = S( 45, 40);
constexpr Score ThreatByRank = S( 16, 3);
- constexpr Score ThreatBySafePawn = S(175,168);
+ constexpr Score ThreatBySafePawn = S(173,102);
constexpr Score TrappedRook = S( 92, 0);
constexpr Score WeakQueen = S( 50, 10);
- constexpr Score WeakUnopposedPawn = S( 5, 25);
+ constexpr Score WeakUnopposedPawn = S( 5, 29);
#undef S
// Find our pawns that are blocked or on the first two ranks
Bitboard b = pos.pieces(Us, PAWN) & (shift<Down>(pos.pieces()) | LowRanks);
- // Squares occupied by those pawns, by our king, or controlled by enemy pawns
+ // Squares occupied by those pawns, by our king or queen, or controlled by enemy pawns
// are excluded from the mobility area.
- mobilityArea[Us] = ~(b | pos.square<KING>(Us) | pe->pawn_attacks(Them));
+ mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them));
// Initialise attackedBy bitboards for kings and pawns
attackedBy[Us][KING] = pos.attacks_from<KING>(pos.square<KING>(Us));
else if (file_of(pos.square<KING>(Us)) == FILE_A)
kingRing[Us] |= shift<EAST>(kingRing[Us]);
- kingAttackersCount[Them] = popcount(attackedBy[Us][KING] & pe->pawn_attacks(Them));
+ kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them));
kingAttacksCount[Them] = kingAttackersWeight[Them] = 0;
}
else
template<Tracing T> template<Color Us, PieceType Pt>
Score Evaluation<T>::pieces() {
- constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
: Rank5BB | Rank4BB | Rank3BB);
const Square* pl = pos.squares<Pt>(Us);
mobility[Us] += MobilityBonus[Pt - 2][mob];
- // Penalty if the piece is far from the king
- score -= KingProtector[Pt - 2] * distance(s, pos.square<KING>(Us));
-
if (Pt == BISHOP || Pt == KNIGHT)
{
// Bonus if piece is on an outpost square or can reach one
else if (bb &= b & ~pos.pieces(Us))
score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)];
- // Bonus when behind a pawn
- if ( relative_rank(Us, s) < RANK_5
- && (pos.pieces(PAWN) & (s + pawn_push(Us))))
+ // Knight and Bishop bonus for being right behind a pawn
+ if (shift<Down>(pos.pieces(PAWN)) & s)
score += MinorBehindPawn;
+ // Penalty if the piece is far from the king
+ score -= KingProtector[Pt == BISHOP] * distance(s, pos.square<KING>(Us));
+
if (Pt == BISHOP)
{
- // Penalty according to number of pawns on the same color square as the bishop
- score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s);
+ // Penalty according to number of pawns on the same color square as the
+ // bishop, bigger when the center files are blocked with pawns.
+ Bitboard blocked = pos.pieces(Us, PAWN) & shift<Down>(pos.pieces());
+
+ score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s)
+ * (1 + popcount(blocked & CenterFiles));
// Bonus for bishop on a long diagonal which can "see" both center squares
if (more_than_one(Center & (attacks_bb<BISHOP>(s, pos.pieces(PAWN)) | s)))
if (Pt == ROOK)
{
- // Bonus for aligning rook with with enemy pawns on the same rank/file
+ // Bonus for aligning rook with enemy pawns on the same rank/file
if (relative_rank(Us, s) >= RANK_5)
score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]);
: AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB);
const Square ksq = pos.square<KING>(Us);
- Bitboard weak, b, b1, b2, safe, unsafeChecks, pinned;
+ Bitboard weak, b, b1, b2, safe, unsafeChecks;
// King shelter and enemy pawns storm
Score score = pe->king_safety<Us>(pos, ksq);
// Unsafe or occupied checking squares will also be considered, as long as
// the square is in the attacker's mobility area.
unsafeChecks &= mobilityArea[Them];
- pinned = pos.blockers_for_king(Us) & pos.pieces(Us);
kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them]
- + 102 * kingAttacksCount[Them]
- + 191 * popcount(kingRing[Us] & weak)
- + 143 * popcount(pinned | unsafeChecks)
- - 848 * !pos.count<QUEEN>(Them)
- - 9 * mg_value(score) / 8
- + 40;
+ + 69 * kingAttacksCount[Them]
+ + 185 * popcount(kingRing[Us] & weak)
+ + 129 * popcount(pos.blockers_for_king(Us) | unsafeChecks)
+ - 873 * !pos.count<QUEEN>(Them)
+ - 6 * mg_value(score) / 8
+ - 2 ;
// Transform the kingDanger units into a Score, and subtract it from the evaluation
if (kingDanger > 0)
Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safeThreats;
Score score = SCORE_ZERO;
- // Non-pawn enemies attacked by a pawn
+ // Non-pawn enemies
nonPawnEnemies = pos.pieces(Them) ^ pos.pieces(Them, PAWN);
- weak = nonPawnEnemies & attackedBy[Us][PAWN];
-
- if (weak)
- {
- // Our safe or protected pawns
- b = pos.pieces(Us, PAWN)
- & (~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]);
-
- safeThreats = pawn_attacks_bb<Us>(b) & weak;
- score += ThreatBySafePawn * popcount(safeThreats);
- }
// Squares strongly protected by the enemy, either because they defend the
// square with a pawn, or because they defend the square twice and we don't.
score += ThreatByRank * (int)relative_rank(Them, s);
}
+ // Bonus for king attacks on pawns or pieces which are not pawn-defended
+ if (weak & attackedBy[Us][KING])
+ score += ThreatByKing;
+
score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]);
- b = weak & attackedBy[Us][KING];
- if (b)
- score += ThreatByKing[more_than_one(b)];
+ // Bonus for overload (non-pawn enemies attacked once or more and defended exactly once)
+ b = nonPawnEnemies
+ & attackedBy[Us][ALL_PIECES]
+ & attackedBy[Them][ALL_PIECES] & ~attackedBy2[Them];
+ score += Overload * popcount(b);
}
// Bonus for enemy unopposed weak pawns
if (pos.pieces(Us, ROOK, QUEEN))
score += WeakUnopposedPawn * pe->weak_unopposed(Them);
+ // Our safe or protected pawns
+ b = pos.pieces(Us, PAWN)
+ & (~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]);
+
+ safeThreats = pawn_attacks_bb<Us>(b) & nonPawnEnemies;
+ score += ThreatBySafePawn * popcount(safeThreats);
+
// Find squares where our pawns can push on the next move
b = shift<Up>(pos.pieces(Us, PAWN)) & ~pos.pieces();
b |= shift<Up>(b & TRank3BB) & ~pos.pieces();
assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
- bb = forward_file_bb(Us, s) & (attackedBy[Them][ALL_PIECES] | pos.pieces(Them));
+ bb = forward_file_bb(Us, s) & pos.pieces(Them);
score -= HinderPassedPawn * popcount(bb);
int r = relative_rank(Us, s);
}
else if (pos.pieces(Us) & blockSq)
bonus += make_score(w + r * 2, w + r * 2);
- } // rr != 0
+ } // w != 0
// Scale down bonus for candidate passers which need more than one
- // pawn push to become passed or have a pawn in front of them.
+ // pawn push to become passed, or have a pawn in front of them.
if ( !pos.pawn_passed(Us, s + Up)
|| (pos.pieces(PAWN) & forward_file_bb(Us, s)))
bonus = bonus / 2;
if (pos.non_pawn_material() < SpaceThreshold)
return SCORE_ZERO;
- // Find the safe squares for our pieces inside the area defined by
- // SpaceMask. A square is unsafe if it is attacked by an enemy
- // pawn, or if it is undefended and attacked by an enemy piece.
+ // Find the available squares for our pieces inside the area defined by SpaceMask
Bitboard safe = SpaceMask
& ~pos.pieces(Us, PAWN)
- & ~attackedBy[Them][PAWN]
- & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]);
+ & ~attackedBy[Them][PAWN];
// Find all squares which are at most three squares behind some friendly pawn
Bitboard behind = pos.pieces(Us, PAWN);
&& (pos.pieces(PAWN) & KingSide);
// Compute the initiative bonus for the attacking side
- int complexity = 8 * outflanking
- + 8 * pe->pawn_asymmetry()
+ int complexity = 8 * pe->pawn_asymmetry()
+ 12 * pos.count<PAWN>()
+ + 12 * outflanking
+ 16 * pawnsOnBothFlanks
+ 48 * !pos.non_pawn_material()
-136 ;
Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
int sf = me->scale_factor(pos, strongSide);
- // If we don't already have an unusual scale factor, check for certain
- // types of endgames, and use a lower scale for those.
- if (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)
+ // If scale is not already specific, scale down the endgame via general heuristics
+ if (sf == SCALE_FACTOR_NORMAL)
{
- if (pos.opposite_bishops())
- {
- // Endgame with opposite-colored bishops and no other pieces (ignoring pawns)
- // is almost a draw, in case of KBP vs KB, it is even more a draw.
- if ( pos.non_pawn_material(WHITE) == BishopValueMg
- && pos.non_pawn_material(BLACK) == BishopValueMg)
- sf = more_than_one(pos.pieces(PAWN)) ? 31 : 9;
-
- // Endgame with opposite-colored bishops, but also other pieces. Still
- // a bit drawish, but not as drawish as with only the two bishops.
- else
- sf = 46;
- }
- // Endings where weaker side can place his king in front of the enemy's
- // pawns are drawish.
- else if ( abs(eg) <= BishopValueEg
- && pos.count<PAWN>(strongSide) <= 2
- && !pos.pawn_passed(~strongSide, pos.square<KING>(~strongSide)))
- sf = 37 + 7 * pos.count<PAWN>(strongSide);
+ if ( pos.opposite_bishops()
+ && pos.non_pawn_material(WHITE) == BishopValueMg
+ && pos.non_pawn_material(BLACK) == BishopValueMg)
+ sf = 31;
+ else
+ sf = std::min(40 + (pos.opposite_bishops() ? 2 : 7) * pos.count<PAWN>(strongSide), sf);
}
return ScaleFactor(sf);
// Initialize score by reading the incrementally updated scores included in
// the position object (material + piece square tables) and the material
// imbalance. Score is computed internally from the white point of view.
- Score score = pos.psq_score() + me->imbalance() + Eval::Contempt;
+ Score score = pos.psq_score() + me->imbalance() + pos.this_thread()->contempt;
// Probe the pawn hash table
pe = Pawns::probe(pos);
std::memset(scores, 0, sizeof(scores));
- Eval::Contempt = SCORE_ZERO; // Reset any dynamic contempt
+ pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
Value v = Evaluation<TRACE>(pos).value();
projects / stockfish / blobdiff