X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fevaluate.cpp;h=fbe768bbbd4d72983fd1abd312ec7c31ba881c58;hb=eb07775583c39893bc6eb65a40b5f62a7799deee;hp=1d2c5f8e55304c1931790fa45c3649e9ddf0f55c;hpb=c163c2fcb0bf6fbb2c41b1399e7928cb76cd6118;p=stockfish
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 1d2c5f8e..fbe768bb 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -2,7 +2,7 @@
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
- Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -18,7 +18,6 @@
along with this program. If not, see .
*/
-#include
#include
#include // For std::memset
#include
@@ -73,28 +72,17 @@ using namespace Trace;
namespace {
- constexpr Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB;
- constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
- constexpr Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB;
- constexpr Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
-
- constexpr Bitboard KingFlank[FILE_NB] = {
- QueenSide, QueenSide, QueenSide,
- CenterFiles, CenterFiles,
- KingSide, KingSide, KingSide
- };
-
// Threshold for lazy and space evaluation
constexpr Value LazyThreshold = Value(1500);
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;
- constexpr int RookSafeCheck = 880;
- constexpr int BishopSafeCheck = 435;
+ constexpr int RookSafeCheck = 1080;
+ constexpr int BishopSafeCheck = 635;
constexpr int KnightSafeCheck = 790;
#define S(mg, eg) make_score(mg, eg)
@@ -102,8 +90,8 @@ namespace {
// MobilityBonus[PieceType-2][attacked] contains bonuses for middle and end game,
// indexed by piece type and number of attacked squares in the mobility area.
constexpr Score MobilityBonus[][32] = {
- { S(-75,-76), S(-57,-54), S( -9,-28), S( -2,-10), S( 6, 5), S( 14, 12), // Knights
- S( 22, 26), S( 29, 29), S( 36, 29) },
+ { S(-62,-81), S(-53,-56), S(-12,-30), S( -4,-14), S( 3, 8), S( 13, 15), // Knights
+ S( 22, 23), S( 28, 27), S( 33, 33) },
{ S(-48,-59), S(-20,-23), S( 16, -3), S( 26, 13), S( 38, 24), S( 51, 42), // Bishops
S( 55, 54), S( 63, 57), S( 63, 65), S( 68, 73), S( 81, 78), S( 81, 86),
S( 91, 88), S( 98, 97) },
@@ -117,70 +105,53 @@ namespace {
S(106,184), S(109,191), S(113,206), S(116,212) }
};
- // Outpost[knight/bishop][supported by pawn] contains bonuses for minor
- // pieces if they occupy or can reach an outpost square, bigger if that
- // square is supported by a pawn.
- constexpr Score Outpost[][2] = {
- { S(22, 6), S(36,12) }, // Knight
- { S( 9, 2), S(15, 5) } // Bishop
- };
-
// RookOnFile[semiopen/open] contains bonuses for each rook when there is
// no (friendly) pawn on the rook file.
- constexpr Score RookOnFile[] = { S(20, 7), S(45, 20) };
+ constexpr Score RookOnFile[] = { S(18, 7), S(44, 20) };
// ThreatByMinor/ByRook[attacked PieceType] contains bonuses according to
// which piece type attacks which one. Attacks on lesser pieces which are
// pawn-defended are not considered.
constexpr Score ThreatByMinor[PIECE_TYPE_NB] = {
- S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(47, 120)
+ S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(62, 120)
};
constexpr Score ThreatByRook[PIECE_TYPE_NB] = {
- S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(36, 38)
+ S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(51, 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(18, 23), S(74, 58), S(164, 166), S(268, 243)
+ 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( 15, 7), S(-5, 14), S( 1, -5), S(-22,-11),
- S(-22,-11), S( 1, -5), S(-5, 14), S( 15, 7)
+ 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, 3, 6, 12, 21 };
-
- // 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) };
-
// Assorted bonuses and penalties
- constexpr Score BishopPawns = S( 3, 5);
- constexpr Score CloseEnemies = S( 7, 0);
- constexpr Score Connectivity = S( 3, 1);
+ constexpr Score BishopPawns = S( 3, 7);
constexpr Score CorneredBishop = S( 50, 50);
- constexpr Score Hanging = S( 52, 30);
- constexpr Score HinderPassedPawn = S( 8, 1);
- 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 ThreatByRank = S( 16, 3);
- constexpr Score ThreatBySafePawn = S(175,168);
- constexpr Score TrappedRook = S( 92, 0);
- constexpr Score WeakQueen = S( 50, 10);
- constexpr Score WeakUnopposedPawn = S( 5, 25);
+ constexpr Score FlankAttacks = S( 8, 0);
+ constexpr Score Hanging = S( 69, 36);
+ constexpr Score KingProtector = S( 7, 8);
+ constexpr Score KnightOnQueen = S( 16, 12);
+ constexpr Score LongDiagonalBishop = S( 45, 0);
+ constexpr Score MinorBehindPawn = S( 18, 3);
+ constexpr Score Outpost = S( 9, 3);
+ constexpr Score PawnlessFlank = S( 17, 95);
+ constexpr Score RestrictedPiece = S( 7, 7);
+ constexpr Score RookOnPawn = S( 10, 32);
+ constexpr Score SliderOnQueen = S( 59, 18);
+ constexpr Score ThreatByKing = S( 24, 89);
+ constexpr Score ThreatByPawnPush = S( 48, 39);
+ constexpr Score ThreatByRank = S( 13, 0);
+ constexpr Score ThreatBySafePawn = S(173, 94);
+ constexpr Score TrappedRook = S( 47, 4);
+ constexpr Score WeakQueen = S( 49, 15);
+ constexpr Score WeakUnopposedPawn = S( 12, 23);
#undef S
@@ -223,7 +194,7 @@ namespace {
// kingRing[color] are the squares adjacent to the king, plus (only for a
// king on its first rank) the squares two ranks in front. For instance,
// if black's king is on g8, kingRing[BLACK] is f8, h8, f7, g7, h7, f6, g6
- // and h6. It is set to 0 when king safety evaluation is skipped.
+ // and h6.
Bitboard kingRing[COLOR_NB];
// kingAttackersCount[color] is the number of pieces of the given color
@@ -255,37 +226,40 @@ namespace {
constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
constexpr Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB);
+ const Square ksq = pos.square(Us);
+
+ Bitboard dblAttackByPawn = pawn_double_attacks_bb(pos.pieces(Us, PAWN));
+
// Find our pawns that are blocked or on the first two ranks
Bitboard b = pos.pieces(Us, PAWN) & (shift(pos.pieces()) | LowRanks);
- // Squares occupied by those pawns, by our king or queen, or controlled by enemy pawns
- // are excluded from the mobility area.
+ // 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.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them));
- // Initialise attackedBy bitboards for kings and pawns
- attackedBy[Us][KING] = pos.attacks_from(pos.square(Us));
+ // Initialize attackedBy[] for king and pawns
+ attackedBy[Us][KING] = pos.attacks_from(ksq);
attackedBy[Us][PAWN] = pe->pawn_attacks(Us);
attackedBy[Us][ALL_PIECES] = attackedBy[Us][KING] | attackedBy[Us][PAWN];
- attackedBy2[Us] = attackedBy[Us][KING] & attackedBy[Us][PAWN];
+ attackedBy2[Us] = (attackedBy[Us][KING] & attackedBy[Us][PAWN])
+ | dblAttackByPawn;
- // Init our king safety tables only if we are going to use them
- if (pos.non_pawn_material(Them) >= RookValueMg + KnightValueMg)
- {
- kingRing[Us] = attackedBy[Us][KING];
- if (relative_rank(Us, pos.square(Us)) == RANK_1)
- kingRing[Us] |= shift(kingRing[Us]);
+ // Init our king safety tables
+ kingRing[Us] = attackedBy[Us][KING];
+ if (relative_rank(Us, ksq) == RANK_1)
+ kingRing[Us] |= shift(kingRing[Us]);
- if (file_of(pos.square(Us)) == FILE_H)
- kingRing[Us] |= shift(kingRing[Us]);
+ if (file_of(ksq) == FILE_H)
+ kingRing[Us] |= shift(kingRing[Us]);
- else if (file_of(pos.square(Us)) == FILE_A)
- kingRing[Us] |= shift(kingRing[Us]);
+ else if (file_of(ksq) == FILE_A)
+ kingRing[Us] |= shift(kingRing[Us]);
- kingAttackersCount[Them] = popcount(attackedBy[Us][KING] & pe->pawn_attacks(Them));
- kingAttacksCount[Them] = kingAttackersWeight[Them] = 0;
- }
- else
- kingRing[Us] = kingAttackersCount[Them] = 0;
+ kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them));
+ kingAttacksCount[Them] = kingAttackersWeight[Them] = 0;
+
+ // Remove from kingRing[] the squares defended by two pawns
+ kingRing[Us] &= ~dblAttackByPawn;
}
@@ -300,12 +274,11 @@ namespace {
const Square* pl = pos.squares(Us);
Bitboard b, bb;
- Square s;
Score score = SCORE_ZERO;
attackedBy[Us][Pt] = 0;
- while ((s = *pl++) != SQ_NONE)
+ for (Square s = *pl; s != SQ_NONE; s = *++pl)
{
// Find attacked squares, including x-ray attacks for bishops and rooks
b = Pt == BISHOP ? attacks_bb(s, pos.pieces() ^ pos.pieces(QUEEN))
@@ -330,24 +303,25 @@ namespace {
mobility[Us] += MobilityBonus[Pt - 2][mob];
- // Penalty if the piece is far from the king
- score -= KingProtector[Pt - 2] * distance(s, pos.square(Us));
-
if (Pt == BISHOP || Pt == KNIGHT)
{
// Bonus if piece is on an outpost square or can reach one
bb = OutpostRanks & ~pe->pawn_attacks_span(Them);
if (bb & s)
- score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & s)] * 2;
+ score += Outpost * (Pt == KNIGHT ? 4 : 2)
+ * (1 + bool(attackedBy[Us][PAWN] & s));
else if (bb &= b & ~pos.pieces(Us))
- score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)];
+ score += Outpost * (Pt == KNIGHT ? 2 : 1)
+ * (1 + 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(pos.pieces(PAWN)) & s)
score += MinorBehindPawn;
+ // Penalty if the piece is far from the king
+ score -= KingProtector * distance(s, pos.square(Us));
+
if (Pt == BISHOP)
{
// Penalty according to number of pawns on the same color square as the
@@ -358,7 +332,7 @@ namespace {
* (1 + popcount(blocked & CenterFiles));
// Bonus for bishop on a long diagonal which can "see" both center squares
- if (more_than_one(Center & (attacks_bb(s, pos.pieces(PAWN)) | s)))
+ if (more_than_one(attacks_bb(s, pos.pieces(PAWN)) & Center))
score += LongDiagonalBishop;
}
@@ -384,15 +358,15 @@ namespace {
score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]);
// Bonus for rook on an open or semi-open file
- if (pe->semiopen_file(Us, file_of(s)))
- score += RookOnFile[bool(pe->semiopen_file(Them, file_of(s)))];
+ if (pos.semiopen_file(Us, file_of(s)))
+ score += RookOnFile[bool(pos.semiopen_file(Them, file_of(s)))];
// Penalty when trapped by the king, even more if the king cannot castle
else if (mob <= 3)
{
File kf = file_of(pos.square(Us));
if ((kf < FILE_E) == (file_of(s) < kf))
- score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us));
+ score -= TrappedRook * (1 + !pos.castling_rights(Us));
}
}
@@ -419,90 +393,97 @@ namespace {
constexpr Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB
: AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB);
+ Bitboard weak, b1, b2, safe, unsafeChecks = 0;
+ Bitboard rookChecks, queenChecks, bishopChecks, knightChecks;
+ int kingDanger = 0;
const Square ksq = pos.square(Us);
- Bitboard weak, b, b1, b2, safe, unsafeChecks;
- // King shelter and enemy pawns storm
- Score score = pe->king_safety(pos, ksq);
+ // Init the score with king shelter and enemy pawns storm
+ Score score = pe->king_safety(pos);
- // Main king safety evaluation
- if (kingAttackersCount[Them] > 1 - pos.count(Them))
- {
- int kingDanger = 0;
- unsafeChecks = 0;
+ // Attacked squares defended at most once by our queen or king
+ weak = attackedBy[Them][ALL_PIECES]
+ & ~attackedBy2[Us]
+ & (~attackedBy[Us][ALL_PIECES] | attackedBy[Us][KING] | attackedBy[Us][QUEEN]);
- // Attacked squares defended at most once by our queen or king
- weak = attackedBy[Them][ALL_PIECES]
- & ~attackedBy2[Us]
- & (~attackedBy[Us][ALL_PIECES] | attackedBy[Us][KING] | attackedBy[Us][QUEEN]);
+ // Analyse the safe enemy's checks which are possible on next move
+ safe = ~pos.pieces(Them);
+ safe &= ~attackedBy[Us][ALL_PIECES] | (weak & attackedBy2[Them]);
- // Analyse the safe enemy's checks which are possible on next move
- safe = ~pos.pieces(Them);
- safe &= ~attackedBy[Us][ALL_PIECES] | (weak & attackedBy2[Them]);
+ b1 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN));
+ b2 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN));
- b1 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN));
- b2 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN));
+ // Enemy rooks checks
+ rookChecks = b1 & safe & attackedBy[Them][ROOK];
- // Enemy queen safe checks
- if ((b1 | b2) & attackedBy[Them][QUEEN] & safe & ~attackedBy[Us][QUEEN])
- kingDanger += QueenSafeCheck;
-
- b1 &= attackedBy[Them][ROOK];
- b2 &= attackedBy[Them][BISHOP];
+ if (rookChecks)
+ kingDanger += RookSafeCheck;
+ else
+ unsafeChecks |= b1 & attackedBy[Them][ROOK];
+
+ // Enemy queen safe checks: we count them only if they are from squares from
+ // which we can't give a rook check, because rook checks are more valuable.
+ queenChecks = (b1 | b2)
+ & attackedBy[Them][QUEEN]
+ & safe
+ & ~attackedBy[Us][QUEEN]
+ & ~rookChecks;
+
+ if (queenChecks)
+ kingDanger += QueenSafeCheck;
+
+ // Enemy bishops checks: we count them only if they are from squares from
+ // which we can't give a queen check, because queen checks are more valuable.
+ bishopChecks = b2
+ & attackedBy[Them][BISHOP]
+ & safe
+ & ~queenChecks;
+
+ if (bishopChecks)
+ kingDanger += BishopSafeCheck;
+ else
+ unsafeChecks |= b2 & attackedBy[Them][BISHOP];
- // Enemy rooks checks
- if (b1 & safe)
- kingDanger += RookSafeCheck;
- else
- unsafeChecks |= b1;
+ // Enemy knights checks
+ knightChecks = pos.attacks_from(ksq) & attackedBy[Them][KNIGHT];
- // Enemy bishops checks
- if (b2 & safe)
- kingDanger += BishopSafeCheck;
- else
- unsafeChecks |= b2;
+ if (knightChecks & safe)
+ kingDanger += KnightSafeCheck;
+ else
+ unsafeChecks |= knightChecks;
- // Enemy knights checks
- b = pos.attacks_from(ksq) & attackedBy[Them][KNIGHT];
- if (b & safe)
- kingDanger += KnightSafeCheck;
- else
- unsafeChecks |= b;
-
- // Unsafe or occupied checking squares will also be considered, as long as
- // the square is in the attacker's mobility area.
- unsafeChecks &= mobilityArea[Them];
-
- kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them]
- + 102 * kingAttacksCount[Them]
- + 191 * popcount(kingRing[Us] & weak)
- + 143 * popcount(pos.blockers_for_king(Us) | unsafeChecks)
- - 848 * !pos.count(Them)
- - 9 * mg_value(score) / 8
- + 40;
-
- // Transform the kingDanger units into a Score, and subtract it from the evaluation
- if (kingDanger > 0)
- {
- int mobilityDanger = mg_value(mobility[Them] - mobility[Us]);
- kingDanger = std::max(0, kingDanger + mobilityDanger);
- score -= make_score(kingDanger * kingDanger / 4096, kingDanger / 16);
- }
- }
+ // Unsafe or occupied checking squares will also be considered, as long as
+ // the square is in the attacker's mobility area.
+ unsafeChecks &= mobilityArea[Them];
- Bitboard kf = KingFlank[file_of(ksq)];
+ // Find the squares that opponent attacks in our king flank, and the squares
+ // which are attacked twice in that flank.
+ b1 = attackedBy[Them][ALL_PIECES] & KingFlank[file_of(ksq)] & Camp;
+ b2 = b1 & attackedBy2[Them];
+
+ int kingFlankAttacks = popcount(b1) + popcount(b2);
+
+ kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them]
+ + 69 * kingAttacksCount[Them]
+ + 185 * popcount(kingRing[Us] & weak)
+ - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING])
+ + 150 * popcount(pos.blockers_for_king(Us) | unsafeChecks)
+ - 873 * !pos.count(Them)
+ - 6 * mg_value(score) / 8
+ + mg_value(mobility[Them] - mobility[Us])
+ + 5 * kingFlankAttacks * kingFlankAttacks / 16
+ - 15;
+
+ // Transform the kingDanger units into a Score, and subtract it from the evaluation
+ if (kingDanger > 100)
+ score -= make_score(kingDanger * kingDanger / 4096, kingDanger / 16);
// Penalty when our king is on a pawnless flank
- if (!(pos.pieces(PAWN) & kf))
+ if (!(pos.pieces(PAWN) & KingFlank[file_of(ksq)]))
score -= PawnlessFlank;
- // Find the squares that opponent attacks in our king flank, and the squares
- // which are attacked twice in that flank but not defended by our pawns.
- b1 = attackedBy[Them][ALL_PIECES] & kf & Camp;
- b2 = b1 & attackedBy2[Them] & ~attackedBy[Us][PAWN];
-
- // King tropism, to anticipate slow motion attacks on our king
- score -= CloseEnemies * (popcount(b1) + popcount(b2));
+ // Penalty if king flank is under attack, potentially moving toward the king
+ score -= FlankAttacks * kingFlankAttacks;
if (T)
Trace::add(KING, Us, score);
@@ -520,11 +501,11 @@ namespace {
constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB);
- Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safeThreats;
+ Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe;
Score score = SCORE_ZERO;
// Non-pawn enemies
- nonPawnEnemies = pos.pieces(Them) ^ pos.pieces(Them, PAWN);
+ nonPawnEnemies = pos.pieces(Them) & ~pos.pieces(PAWN);
// 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.
@@ -537,6 +518,9 @@ namespace {
// Enemies not strongly protected and under our attack
weak = pos.pieces(Them) & ~stronglyProtected & attackedBy[Us][ALL_PIECES];
+ // Safe or protected squares
+ safe = ~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES];
+
// Bonus according to the kind of attacking pieces
if (defended | weak)
{
@@ -549,7 +533,7 @@ namespace {
score += ThreatByRank * (int)relative_rank(Them, s);
}
- b = (pos.pieces(Them, QUEEN) | weak) & attackedBy[Us][ROOK];
+ b = weak & attackedBy[Us][ROOK];
while (b)
{
Square s = pop_lsb(&b);
@@ -558,65 +542,58 @@ namespace {
score += ThreatByRank * (int)relative_rank(Them, s);
}
- b = weak & attackedBy[Us][KING];
- if (b)
- score += ThreatByKing[more_than_one(b)];
+ if (weak & attackedBy[Us][KING])
+ score += ThreatByKing;
- score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]);
-
- // Bonus for overload (non-pawn enemies attacked and defended exactly once)
- b = nonPawnEnemies
- & attackedBy[Us][ALL_PIECES] & ~attackedBy2[Us]
- & attackedBy[Them][ALL_PIECES] & ~attackedBy2[Them];
- score += Overload * popcount(b);
+ b = ~attackedBy[Them][ALL_PIECES]
+ | (nonPawnEnemies & attackedBy2[Us]);
+ score += Hanging * popcount(weak & b);
}
+ // Bonus for restricting their piece moves
+ b = attackedBy[Them][ALL_PIECES]
+ & ~stronglyProtected
+ & attackedBy[Us][ALL_PIECES];
+
+ score += RestrictedPiece * 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(b) & nonPawnEnemies;
- score += ThreatBySafePawn * popcount(safeThreats);
-
// Find squares where our pawns can push on the next move
b = shift(pos.pieces(Us, PAWN)) & ~pos.pieces();
b |= shift(b & TRank3BB) & ~pos.pieces();
- // Keep only the squares which are not completely unsafe
- b &= ~attackedBy[Them][PAWN]
- & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]);
+ // Keep only the squares which are relatively safe
+ b &= ~attackedBy[Them][PAWN] & safe;
// Bonus for safe pawn threats on the next move
- b = pawn_attacks_bb(b)
- & pos.pieces(Them)
- & ~attackedBy[Us][PAWN];
-
+ b = pawn_attacks_bb(b) & pos.pieces(Them);
score += ThreatByPawnPush * popcount(b);
+ // Our safe or protected pawns
+ b = pos.pieces(Us, PAWN) & safe;
+
+ b = pawn_attacks_bb(b) & nonPawnEnemies;
+ score += ThreatBySafePawn * popcount(b);
+
// Bonus for threats on the next moves against enemy queen
if (pos.count(Them) == 1)
{
Square s = pos.square(Them);
- safeThreats = mobilityArea[Us] & ~stronglyProtected;
+ safe = mobilityArea[Us] & ~stronglyProtected;
b = attackedBy[Us][KNIGHT] & pos.attacks_from(s);
- score += KnightOnQueen * popcount(b & safeThreats);
+ score += KnightOnQueen * popcount(b & safe);
b = (attackedBy[Us][BISHOP] & pos.attacks_from(s))
| (attackedBy[Us][ROOK ] & pos.attacks_from(s));
- score += SliderOnQueen * popcount(b & safeThreats & attackedBy2[Us]);
+ score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]);
}
- // Connectivity: ensure that knights, bishops, rooks, and queens are protected
- b = (pos.pieces(Us) ^ pos.pieces(Us, PAWN, KING)) & attackedBy[Us][ALL_PIECES];
- score += Connectivity * popcount(b);
-
if (T)
Trace::add(THREAT, Us, score);
@@ -647,16 +624,13 @@ namespace {
assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
- bb = forward_file_bb(Us, s) & (attackedBy[Them][ALL_PIECES] | pos.pieces(Them));
- score -= HinderPassedPawn * popcount(bb);
-
int r = relative_rank(Us, s);
- int w = PassedDanger[r];
Score bonus = PassedRank[r];
- if (w)
+ if (r > RANK_3)
{
+ int w = (r-2) * (r-2) + 2;
Square blockSq = s + Up;
// Adjust bonus based on the king's proximity
@@ -697,9 +671,7 @@ namespace {
bonus += make_score(k * w, k * w);
}
- else if (pos.pieces(Us) & blockSq)
- bonus += make_score(w + r * 2, w + r * 2);
- } // w != 0
+ } // rank > RANK_3
// Scale down bonus for candidate passers which need more than one
// pawn push to become passed, or have a pawn in front of them.
@@ -727,14 +699,15 @@ namespace {
template template
Score Evaluation::space() const {
- constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ if (pos.non_pawn_material() < SpaceThreshold)
+ return SCORE_ZERO;
+
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
constexpr Bitboard SpaceMask =
Us == WHITE ? CenterFiles & (Rank2BB | Rank3BB | Rank4BB)
: CenterFiles & (Rank7BB | Rank6BB | Rank5BB);
- if (pos.non_pawn_material() < SpaceThreshold)
- return SCORE_ZERO;
-
// Find the available squares for our pieces inside the area defined by SpaceMask
Bitboard safe = SpaceMask
& ~pos.pieces(Us, PAWN)
@@ -742,11 +715,12 @@ namespace {
// Find all squares which are at most three squares behind some friendly pawn
Bitboard behind = pos.pieces(Us, PAWN);
- behind |= (Us == WHITE ? behind >> 8 : behind << 8);
- behind |= (Us == WHITE ? behind >> 16 : behind << 16);
+ behind |= shift(behind);
+ behind |= shift(shift(behind));
int bonus = popcount(safe) + popcount(behind & safe);
- int weight = pos.count(Us) - 2 * pe->open_files();
+ int weight = pos.count(Us)
+ - (16 - pos.count()) / 4;
Score score = make_score(bonus * weight * weight / 16, 0);
@@ -771,12 +745,12 @@ namespace {
&& (pos.pieces(PAWN) & KingSide);
// Compute the initiative bonus for the attacking side
- int complexity = 8 * outflanking
- + 8 * pe->pawn_asymmetry()
- + 12 * pos.count()
- + 16 * pawnsOnBothFlanks
- + 48 * !pos.non_pawn_material()
- -136 ;
+ int complexity = 9 * pe->passed_count()
+ + 11 * pos.count()
+ + 9 * outflanking
+ + 18 * pawnsOnBothFlanks
+ + 49 * !pos.non_pawn_material()
+ -103 ;
// Now apply the bonus: note that we find the attacking side by extracting
// the sign of the endgame value, and that we carefully cap the bonus so
@@ -801,20 +775,13 @@ namespace {
// 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 is almost a draw
- if ( pos.non_pawn_material(WHITE) == BishopValueMg
- && pos.non_pawn_material(BLACK) == BishopValueMg)
- sf = 31;
-
- // 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;
- }
+ if ( pos.opposite_bishops()
+ && pos.non_pawn_material(WHITE) == BishopValueMg
+ && pos.non_pawn_material(BLACK) == BishopValueMg)
+ sf = 16 + 4 * pe->passed_count();
else
- sf = std::min(40 + 7 * pos.count(strongSide), sf);
+ sf = std::min(40 + (pos.opposite_bishops() ? 2 : 7) * pos.count(strongSide), sf);
+
}
return ScaleFactor(sf);
@@ -877,7 +844,7 @@ namespace {
v = mg_value(score) * int(me->game_phase())
+ eg_value(score) * int(PHASE_MIDGAME - me->game_phase()) * sf / SCALE_FACTOR_NORMAL;
- v /= int(PHASE_MIDGAME);
+ v /= PHASE_MIDGAME;
// In case of tracing add all remaining individual evaluation terms
if (T)
@@ -925,7 +892,6 @@ std::string Eval::trace(const Position& pos) {
<< " ------------+-------------+-------------+------------\n"
<< " Material | " << Term(MATERIAL)
<< " Imbalance | " << Term(IMBALANCE)
- << " Initiative | " << Term(INITIATIVE)
<< " Pawns | " << Term(PAWN)
<< " Knights | " << Term(KNIGHT)
<< " Bishops | " << Term(BISHOP)
@@ -936,6 +902,7 @@ std::string Eval::trace(const Position& pos) {
<< " Threats | " << Term(THREAT)
<< " Passed | " << Term(PASSED)
<< " Space | " << Term(SPACE)
+ << " Initiative | " << Term(INITIATIVE)
<< " ------------+-------------+-------------+------------\n"
<< " Total | " << Term(TOTAL);