/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, 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
namespace {
+ enum ExtendedPieceType { // Used for tracing
+ PST = 8, IMBALANCE, MOBILITY, THREAT, PASSED, UNSTOPPABLE, SPACE, TOTAL
+ };
+
+ namespace Tracing {
+
+ Score scores[COLOR_NB][TOTAL + 1];
+ std::stringstream stream;
+
+ void add(int idx, Score term_w, Score term_b = SCORE_ZERO);
+ void row(const char* name, int idx);
+ std::string do_trace(const Position& pos);
+ }
+
// Struct EvalInfo contains various information computed and collected
// by the evaluation functions.
struct EvalInfo {
Pawns::Entry* pi;
// attackedBy[color][piece type] is a bitboard representing all squares
- // attacked by a given color and piece type, attackedBy[color][0] contains
- // all squares attacked by the given color.
+ // attacked by a given color and piece type, attackedBy[color][ALL_PIECES]
+ // contains all squares attacked by the given color.
Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
// kingRing[color] is the zone around the king which is considered
};
// Evaluation grain size, must be a power of 2
- const int GrainSize = 8;
+ const int GrainSize = 4;
// Evaluation weights, initialized from UCI options
- enum { Mobility, PassedPawns, Space };
- Score Weights[3];
+ enum { Mobility, PawnStructure, PassedPawns, Space, KingDangerUs, KingDangerThem };
+ Score Weights[6];
typedef Value V;
#define S(mg, eg) make_score(mg, eg)
//
// Values modified by Joona Kiiski
const Score WeightsInternal[] = {
- S(252, 344), S(216, 266), S(46, 0)
+ S(289, 344), S(233, 201), S(221, 273), S(46, 0), S(271, 0), S(307, 0)
};
- // MobilityBonus[PieceType][attacked] contains mobility bonuses for middle and
- // end game, indexed by piece type and number of attacked squares not occupied
- // by friendly pieces.
+ // MobilityBonus[PieceType][attacked] contains bonuses for middle and end
+ // game, indexed by piece type and number of attacked squares not occupied by
+ // friendly pieces.
const Score MobilityBonus[][32] = {
{}, {},
- { S(-38,-33), S(-25,-23), S(-12,-13), S( 0, -3), S(12, 7), S(25, 17), // Knights
- S( 31, 22), S( 38, 27), S( 38, 27) },
- { S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12), S(31, 26), S(45, 40), // Bishops
- 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) },
- { S(-20,-36), S(-14,-19), S( -8, -3), S(-2, 13), S( 4, 29), S(10, 46), // Rooks
- 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) },
- { S(-10,-18), S( -8,-13), S( -6, -7), S(-3, -2), S(-1, 3), S( 1, 8), // Queens
- 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) }
+ { S(-35,-30), S(-22,-20), S(-9,-10), S( 3, 0), S(15, 10), S(27, 20), // Knights
+ S( 37, 28), S( 42, 31), S(44, 33) },
+ { S(-22,-27), S( -8,-13), S( 6, 1), S(20, 15), S(34, 29), S(48, 43), // Bishops
+ S( 60, 55), S( 68, 63), S(74, 68), S(77, 72), S(80, 75), S(82, 77),
+ S( 84, 79), S( 86, 81), S(87, 82), S(87, 82) },
+ { S(-17,-33), S(-11,-16), S(-5, 0), S( 1, 16), S( 7, 32), S(13, 48), // Rooks
+ S( 18, 64), S( 22, 80), S(26, 96), S(29,109), S(31,115), S(33,119),
+ S( 35,122), S( 36,123), S(37,124), S(38,124) },
+ { S(-12,-20), S( -8,-13), S(-5, -7), S(-2, -1), S( 1, 5), S( 4, 11), // Queens
+ S( 7, 17), S( 10, 23), S(13, 29), S(16, 34), S(18, 38), S(20, 40),
+ S( 22, 41), S( 23, 41), S(24, 41), S(25, 41), S(25, 41), S(25, 41),
+ S( 25, 41), S( 25, 41), S(25, 41), S(25, 41), S(25, 41), S(25, 41),
+ S( 25, 41), S( 25, 41), S(25, 41), S(25, 41), S(25, 41), S(25, 41),
+ S( 25, 41), S( 25, 41) }
};
- // OutpostBonus[PieceType][Square] contains outpost bonuses of knights and
- // bishops, indexed by piece type and square (from white's point of view).
- const Value OutpostBonus[][SQUARE_NB] = {
+ // Outpost[PieceType][Square] contains bonuses of knights and bishops, indexed
+ // by piece type and square (from white's point of view).
+ const Value Outpost[][SQUARE_NB] = {
{
// A B C D E F G H
V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights
V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) }
};
- // ThreatBonus[attacking][attacked] contains threat bonuses according to
- // which piece type attacks which one.
- const Score ThreatBonus[][PIECE_TYPE_NB] = {
+ // Threat[attacking][attacked] contains bonuses according to which piece
+ // type attacks which one.
+ const Score Threat[][PIECE_TYPE_NB] = {
{}, {},
{ S(0, 0), S( 7, 39), S( 0, 0), S(24, 49), S(41,100), S(41,100) }, // KNIGHT
{ S(0, 0), S( 7, 39), S(24, 49), S( 0, 0), S(41,100), S(41,100) }, // BISHOP
{ S(0, 0), S(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN
};
- // ThreatenedByPawnPenalty[PieceType] contains a penalty according to which
- // piece type is attacked by an enemy pawn.
- const Score ThreatenedByPawnPenalty[] = {
+ // ThreatenedByPawn[PieceType] contains a penalty according to which piece
+ // type is attacked by an enemy pawn.
+ const Score ThreatenedByPawn[] = {
S(0, 0), S(0, 0), S(56, 70), S(56, 70), S(76, 99), S(86, 118)
};
#undef S
- // Bonus for having the side to move (modified by Joona Kiiski)
- const Score Tempo = make_score(24, 11);
-
- // Rooks and queens on the 7th rank
- const Score RookOn7thBonus = make_score(3, 20);
- const Score QueenOn7thBonus = make_score(1, 8);
-
- // Rooks and queens attacking pawns on the same rank
- const Score RookOnPawnBonus = make_score(3, 48);
- const Score QueenOnPawnBonus = make_score(1, 40);
-
- // Rooks on open files (modified by Joona Kiiski)
- const Score RookOpenFileBonus = make_score(43, 21);
- const Score RookHalfOpenFileBonus = make_score(19, 10);
-
- // Penalty for rooks trapped inside a friendly king which has lost the
- // right to castle.
- const Value TrappedRookPenalty = Value(180);
+ const Score Tempo = make_score(24, 11);
+ const Score BishopPin = make_score(66, 11);
+ const Score RookOn7th = make_score(11, 20);
+ const Score QueenOn7th = make_score( 3, 8);
+ const Score RookOnPawn = make_score(10, 28);
+ const Score QueenOnPawn = make_score( 4, 20);
+ const Score RookOpenFile = make_score(43, 21);
+ const Score RookSemiopenFile = make_score(19, 10);
+ const Score BishopPawns = make_score( 8, 12);
+ const Score UndefendedMinor = make_score(25, 10);
+ const Score TrappedRook = make_score(90, 0);
// 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 Score TrappedBishopA1H1Penalty = make_score(100, 100);
-
- // Penalty for an undefended bishop or knight
- const Score UndefendedMinorPenalty = make_score(25, 10);
+ const Score TrappedBishopA1H1 = make_score(50, 50);
// 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
};
// King danger constants and variables. The king danger scores are taken
- // from the KingDangerTable[]. Various little "meta-bonuses" measuring
+ // from the KingDanger[]. Various little "meta-bonuses" measuring
// the strength of the enemy attack are added up into an integer, which
- // is used as an index to KingDangerTable[].
+ // is used as an index to KingDanger[].
//
- // King safety evaluation is asymmetrical and different for us (root color)
- // and for our opponent. These values are used to init KingDangerTable.
- const int KingDangerWeights[] = { 259, 247 };
-
// KingAttackWeights[PieceType] contains king attack weights by piece type
const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 };
// Bonuses for enemy's safe checks
- const int QueenContactCheckBonus = 6;
- const int RookContactCheckBonus = 4;
- const int QueenCheckBonus = 3;
- const int RookCheckBonus = 2;
- const int BishopCheckBonus = 1;
- const int KnightCheckBonus = 1;
-
- // InitKingDanger[Square] contains penalties based on the position of the
+ const int QueenContactCheck = 6;
+ const int RookContactCheck = 4;
+ const int QueenCheck = 3;
+ const int RookCheck = 2;
+ const int BishopCheck = 1;
+ const int KnightCheck = 1;
+
+ // KingExposed[Square] contains penalties based on the position of the
// defending king, indexed by king's square (from white's point of view).
- const int InitKingDanger[] = {
+ const int KingExposed[] = {
2, 0, 2, 5, 5, 2, 0, 2,
2, 2, 4, 8, 8, 4, 2, 2,
7, 10, 12, 12, 12, 12, 10, 7,
15, 15, 15, 15, 15, 15, 15, 15
};
- // KingDangerTable[Color][attackUnits] contains the actual king danger
- // weighted scores, indexed by color and by a calculated integer number.
- Score KingDangerTable[COLOR_NB][128];
-
- // TracedTerms[Color][PieceType || TracedType] contains a breakdown of the
- // evaluation terms, used when tracing.
- Score TracedScores[COLOR_NB][16];
- std::stringstream TraceStream;
-
- enum TracedType {
- PST = 8, IMBALANCE = 9, MOBILITY = 10, THREAT = 11,
- PASSED = 12, UNSTOPPABLE = 13, SPACE = 14, TOTAL = 15
- };
+ // KingDanger[Color][attackUnits] contains the actual king danger weighted
+ // scores, indexed by color and by a calculated integer number.
+ Score KingDanger[COLOR_NB][128];
// Function prototypes
template<bool Trace>
template<Color Us, bool Trace>
Score evaluate_king(const Position& pos, EvalInfo& ei, Value margins[]);
- template<Color Us>
+ template<Color Us, bool Trace>
Score evaluate_threats(const Position& pos, EvalInfo& ei);
- template<Color Us>
- int evaluate_space(const Position& pos, EvalInfo& ei);
+ template<Color Us, bool Trace>
+ Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
template<Color Us>
- Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei);
+ int evaluate_space(const Position& pos, EvalInfo& ei);
Score evaluate_unstoppable_pawns(const Position& pos, EvalInfo& ei);
Value interpolate(const Score& v, Phase ph, ScaleFactor sf);
+ Score apply_weight(Score v, Score w);
Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight);
double to_cp(Value v);
- void trace_add(int idx, Score term_w, Score term_b = SCORE_ZERO);
- void trace_row(const char* name, int idx);
}
}
+ /// trace() is like evaluate() but instead of a value returns a string suitable
+ /// to be print on stdout with the detailed descriptions and values of each
+ /// evaluation term. Used mainly for debugging.
+ std::string trace(const Position& pos) {
+ return Tracing::do_trace(pos);
+ }
+
+
/// init() computes evaluation weights from the corresponding UCI parameters
/// and setup king tables.
void init() {
- Weights[Mobility] = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightsInternal[Mobility]);
- Weights[PassedPawns] = weight_option("Passed Pawns (Middle Game)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]);
- Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]);
-
- int KingDanger[] = { KingDangerWeights[0], KingDangerWeights[1] };
-
- // If running in analysis mode, make sure we use symmetrical king safety.
- // We do so by replacing both KingDanger weights by their average.
- if (Options["UCI_AnalyseMode"])
- KingDanger[0] = KingDanger[1] = (KingDanger[0] + KingDanger[1]) / 2;
+ Weights[Mobility] = weight_option("Mobility (Midgame)", "Mobility (Endgame)", WeightsInternal[Mobility]);
+ Weights[PawnStructure] = weight_option("Pawn Structure (Midgame)", "Pawn Structure (Endgame)", WeightsInternal[PawnStructure]);
+ Weights[PassedPawns] = weight_option("Passed Pawns (Midgame)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]);
+ Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]);
+ Weights[KingDangerUs] = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]);
+ Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]);
const int MaxSlope = 30;
const int Peak = 1280;
{
t = std::min(Peak, std::min(int(0.4 * i * i), t + MaxSlope));
- KingDangerTable[0][i] = apply_weight(make_score(t, 0), make_score(KingDanger[0], 0));
- KingDangerTable[1][i] = apply_weight(make_score(t, 0), make_score(KingDanger[1], 0));
+ KingDanger[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]);
+ KingDanger[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]);
}
}
-
- /// trace() is like evaluate() but instead of a value returns a string suitable
- /// to be print on stdout with the detailed descriptions and values of each
- /// evaluation term. Used mainly for debugging.
-
- std::string trace(const Position& pos) {
-
- Value margin;
- std::string totals;
-
- Search::RootColor = pos.side_to_move();
-
- TraceStream.str("");
- TraceStream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
- memset(TracedScores, 0, 2 * 16 * sizeof(Score));
-
- do_evaluate<true>(pos, margin);
-
- totals = TraceStream.str();
- TraceStream.str("");
-
- TraceStream << std::setw(21) << "Eval term " << "| White | Black | Total \n"
- << " | MG EG | MG EG | MG EG \n"
- << "---------------------+-------------+-------------+---------------\n";
-
- trace_row("Material, PST, Tempo", PST);
- trace_row("Material imbalance", IMBALANCE);
- trace_row("Pawns", PAWN);
- trace_row("Knights", KNIGHT);
- trace_row("Bishops", BISHOP);
- trace_row("Rooks", ROOK);
- trace_row("Queens", QUEEN);
- trace_row("Mobility", MOBILITY);
- trace_row("King safety", KING);
- trace_row("Threats", THREAT);
- trace_row("Passed pawns", PASSED);
- trace_row("Unstoppable pawns", UNSTOPPABLE);
- trace_row("Space", SPACE);
-
- TraceStream << "---------------------+-------------+-------------+---------------\n";
- trace_row("Total", TOTAL);
- TraceStream << totals;
-
- return TraceStream.str();
- }
-
} // namespace Eval
// Probe the pawn hash table
ei.pi = Pawns::probe(pos, th->pawnsTable);
- score += ei.pi->pawns_value();
+ score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]);
// Initialize attack and king safety bitboards
init_eval_info<WHITE>(pos, ei);
- evaluate_king<BLACK, Trace>(pos, ei, margins);
// Evaluate tactical threats, we need full attack information including king
- score += evaluate_threats<WHITE>(pos, ei)
- - evaluate_threats<BLACK>(pos, ei);
+ score += evaluate_threats<WHITE, Trace>(pos, ei)
+ - evaluate_threats<BLACK, Trace>(pos, ei);
// Evaluate passed pawns, we need full attack information including king
- score += evaluate_passed_pawns<WHITE>(pos, ei)
- - evaluate_passed_pawns<BLACK>(pos, ei);
+ score += evaluate_passed_pawns<WHITE, Trace>(pos, ei)
+ - evaluate_passed_pawns<BLACK, Trace>(pos, ei);
// If one side has only a king, check whether exists any unstoppable passed pawn
if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK))
{
// Check for KBP vs KB with only a single pawn that is almost
// certainly a draw or at least two pawns.
- bool one_pawn = (pos.piece_count(WHITE, PAWN) + pos.piece_count(BLACK, PAWN) == 1);
+ bool one_pawn = (pos.count<PAWN>(WHITE) + pos.count<PAWN>(BLACK) == 1);
sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32);
}
else
// In case of tracing add all single evaluation contributions for both white and black
if (Trace)
{
- trace_add(PST, pos.psq_score());
- trace_add(IMBALANCE, ei.mi->material_value());
- trace_add(PAWN, ei.pi->pawns_value());
- trace_add(MOBILITY, apply_weight(mobilityWhite, Weights[Mobility]), apply_weight(mobilityBlack, Weights[Mobility]));
- trace_add(THREAT, evaluate_threats<WHITE>(pos, ei), evaluate_threats<BLACK>(pos, ei));
- trace_add(PASSED, evaluate_passed_pawns<WHITE>(pos, ei), evaluate_passed_pawns<BLACK>(pos, ei));
- trace_add(UNSTOPPABLE, evaluate_unstoppable_pawns(pos, ei));
+ Tracing::add(PST, pos.psq_score());
+ Tracing::add(IMBALANCE, ei.mi->material_value());
+ Tracing::add(PAWN, ei.pi->pawns_value());
+ Tracing::add(UNSTOPPABLE, evaluate_unstoppable_pawns(pos, ei));
Score w = make_score(ei.mi->space_weight() * evaluate_space<WHITE>(pos, ei), 0);
Score b = make_score(ei.mi->space_weight() * evaluate_space<BLACK>(pos, ei), 0);
- trace_add(SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space]));
- trace_add(TOTAL, score);
- TraceStream << "\nUncertainty margin: White: " << to_cp(margins[WHITE])
- << ", Black: " << to_cp(margins[BLACK])
- << "\nScaling: " << std::noshowpos
- << std::setw(6) << 100.0 * ei.mi->game_phase() / 128.0 << "% MG, "
- << std::setw(6) << 100.0 * (1.0 - ei.mi->game_phase() / 128.0) << "% * "
- << std::setw(6) << (100.0 * sf) / SCALE_FACTOR_NORMAL << "% EG.\n"
- << "Total evaluation: " << to_cp(v);
+ Tracing::add(SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space]));
+ Tracing::add(TOTAL, score);
+ Tracing::stream << "\nUncertainty margin: White: " << to_cp(margins[WHITE])
+ << ", Black: " << to_cp(margins[BLACK])
+ << "\nScaling: " << std::noshowpos
+ << std::setw(6) << 100.0 * ei.mi->game_phase() / 128.0 << "% MG, "
+ << std::setw(6) << 100.0 * (1.0 - ei.mi->game_phase() / 128.0) << "% * "
+ << std::setw(6) << (100.0 * sf) / SCALE_FACTOR_NORMAL << "% EG.\n"
+ << "Total evaluation: " << to_cp(v);
}
return pos.side_to_move() == WHITE ? v : -v;
template<Color Us>
void init_eval_info(const Position& pos, EvalInfo& ei) {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Color Them = (Us == WHITE ? BLACK : WHITE);
+ const Square Down = (Us == WHITE ? DELTA_S : DELTA_N);
Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from<KING>(pos.king_square(Them));
ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
// Init king safety tables only if we are going to use them
- if ( pos.piece_count(Us, QUEEN)
- && pos.non_pawn_material(Us) >= QueenValueMg + RookValueMg)
+ if (pos.count<QUEEN>(Us) && pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg)
{
- ei.kingRing[Them] = (b | (Us == WHITE ? b >> 8 : b << 8));
+ ei.kingRing[Them] = b | shift_bb<Down>(b);
b &= ei.attackedBy[Us][PAWN];
ei.kingAttackersCount[Us] = b ? popcount<Max15>(b) / 2 : 0;
ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0;
assert (Piece == BISHOP || Piece == KNIGHT);
// Initial bonus based on square
- Value bonus = OutpostBonus[Piece == BISHOP][relative_square(Us, s)];
+ Value bonus = Outpost[Piece == BISHOP][relative_square(Us, s)];
// Increase bonus if supported by pawn, especially if the opponent has
// no minor piece which can exchange the outpost piece.
Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score& mobility, Bitboard mobilityArea) {
Bitboard b;
- Square s, ksq;
- int mob;
- File f;
+ Square s;
Score score = SCORE_ZERO;
const Color Them = (Us == WHITE ? BLACK : WHITE);
- const Square* pl = pos.piece_list(Us, Piece);
+ const Square* pl = pos.list<Piece>(Us);
ei.attackedBy[Us][Piece] = 0;
while ((s = *pl++) != SQ_NONE)
{
// Find attacked squares, including x-ray attacks for bishops and rooks
- if (Piece == KNIGHT || Piece == QUEEN)
- b = pos.attacks_from<Piece>(s);
- else if (Piece == BISHOP)
- b = attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(Us, QUEEN));
- else if (Piece == ROOK)
- b = attacks_bb<ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN));
- else
- assert(false);
+ b = Piece == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(Us, QUEEN))
+ : Piece == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN))
+ : pos.attacks_from<Piece>(s);
ei.attackedBy[Us][Piece] |= b;
ei.kingAdjacentZoneAttacksCount[Us] += popcount<Max15>(bb);
}
- mob = (Piece != QUEEN ? popcount<Max15>(b & mobilityArea)
- : popcount<Full >(b & mobilityArea));
-
+ int mob = popcount<Piece == QUEEN ? Full : Max15>(b & mobilityArea);
mobility += MobilityBonus[Piece][mob];
- // Add a bonus if a slider is pinning an enemy piece
- if ( (Piece == BISHOP || Piece == ROOK || Piece == QUEEN)
- && (PseudoAttacks[Piece][pos.king_square(Them)] & s))
- {
- b = BetweenBB[s][pos.king_square(Them)] & pos.pieces();
-
- assert(b);
-
- if (!more_than_one(b) && (b & pos.pieces(Them)))
- score += ThreatBonus[Piece][type_of(pos.piece_on(lsb(b)))];
- }
-
// 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 (ei.attackedBy[Them][PAWN] & s)
- score -= ThreatenedByPawnPenalty[Piece];
+ score -= ThreatenedByPawn[Piece];
+
+ // Otherwise give a bonus if we are a bishop and can pin a piece or can
+ // give a discovered check through an x-ray attack.
+ else if ( Piece == BISHOP
+ && (PseudoAttacks[Piece][pos.king_square(Them)] & s)
+ && !more_than_one(BetweenBB[s][pos.king_square(Them)] & pos.pieces()))
+ score += BishopPin;
+
+ // Penalty for bishop with same coloured pawns
+ if (Piece == BISHOP)
+ score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s);
// Bishop and knight outposts squares
if ( (Piece == BISHOP || Piece == KNIGHT)
&& !(pos.pieces(Them, PAWN) & attack_span_mask(Us, s)))
score += evaluate_outposts<Piece, Us>(pos, ei, s);
- if ((Piece == ROOK || Piece == QUEEN) && relative_rank(Us, s) >= RANK_5)
+ if ( (Piece == ROOK || Piece == QUEEN)
+ && relative_rank(Us, s) >= RANK_5)
{
- // Major piece on 7th rank
+ // Major piece on 7th rank and enemy king trapped on 8th
if ( relative_rank(Us, s) == RANK_7
&& relative_rank(Us, pos.king_square(Them)) == RANK_8)
- score += (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus);
+ score += Piece == ROOK ? RookOn7th : QueenOn7th;
- // Major piece attacking pawns on the same rank
+ // Major piece attacking enemy pawns on the same rank
Bitboard pawns = pos.pieces(Them, PAWN) & rank_bb(s);
if (pawns)
- score += (Piece == ROOK ? RookOnPawnBonus
- : QueenOnPawnBonus) * popcount<Max15>(pawns);
- }
-
- // Special extra evaluation for bishops
- if (Piece == BISHOP && pos.is_chess960())
- {
- // An important Chess960 pattern: A cornered bishop blocked by
- // a friendly pawn diagonally in front of it is a very serious
- // problem, especially when that pawn is also blocked.
- if (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))
- {
- Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
- if (pos.piece_on(s + d) == make_piece(Us, PAWN))
- {
- if (!pos.is_empty(s + d + pawn_push(Us)))
- score -= 2*TrappedBishopA1H1Penalty;
- else if (pos.piece_on(s + 2*d) == make_piece(Us, PAWN))
- score -= TrappedBishopA1H1Penalty;
- else
- score -= TrappedBishopA1H1Penalty / 2;
- }
- }
+ score += popcount<Max15>(pawns) * (Piece == ROOK ? RookOnPawn : QueenOnPawn);
}
// Special extra evaluation for rooks
if (Piece == ROOK)
{
- // Open and half-open files
- f = file_of(s);
- if (ei.pi->file_is_half_open(Us, f))
- {
- if (ei.pi->file_is_half_open(Them, f))
- score += RookOpenFileBonus;
- else
- score += RookHalfOpenFileBonus;
- }
+ // Give a bonus for a rook on a open or semi-open file
+ if (ei.pi->semiopen(Us, file_of(s)))
+ score += ei.pi->semiopen(Them, file_of(s)) ? RookOpenFile : RookSemiopenFile;
- // 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->semiopen(Us, file_of(s)))
continue;
- ksq = pos.king_square(Us);
+ Square ksq = pos.king_square(Us);
- if ( file_of(ksq) >= FILE_E
- && file_of(s) > file_of(ksq)
- && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(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, file_of(ksq)))
- score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
- : (TrappedRookPenalty - mob * 16), 0);
- }
- else if ( file_of(ksq) <= FILE_D
- && file_of(s) < file_of(ksq)
- && (relative_rank(Us, ksq) == RANK_1 || rank_of(ksq) == rank_of(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, file_of(ksq)))
- score -= make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2
- : (TrappedRookPenalty - mob * 16), 0);
- }
+ // Penalize rooks which are trapped inside a king. Penalize more if
+ // king has lost right to castle.
+ if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq)))
+ && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1)
+ && !ei.pi->semiopen_on_side(Us, file_of(ksq), file_of(ksq) < FILE_E))
+ score -= (TrappedRook - make_score(mob * 8, 0)) * (pos.can_castle(Us) ? 1 : 2);
+ }
+
+ // An important Chess960 pattern: A cornered bishop blocked by a friendly
+ // pawn diagonally in front of it is a very serious problem, especially
+ // when that pawn is also blocked.
+ if ( Piece == BISHOP
+ && pos.is_chess960()
+ && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)))
+ {
+ const enum Piece P = make_piece(Us, PAWN);
+ Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
+ if (pos.piece_on(s + d) == P)
+ score -= !pos.is_empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4
+ : pos.piece_on(s + d + d) == P ? TrappedBishopA1H1 * 2
+ : TrappedBishopA1H1;
}
}
if (Trace)
- TracedScores[Us][Piece] = score;
+ Tracing::scores[Us][Piece] = score;
return score;
}
// evaluate_threats<>() assigns bonuses according to the type of attacking piece
// and the type of attacked one.
- template<Color Us>
+ template<Color Us, bool Trace>
Score evaluate_threats(const Position& pos, EvalInfo& ei) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
Score score = SCORE_ZERO;
// Undefended minors get penalized even if not under attack
- undefendedMinors = pos.pieces(Them)
- & (pos.pieces(BISHOP) | pos.pieces(KNIGHT))
- & ~ei.attackedBy[Them][0];
+ undefendedMinors = pos.pieces(Them, BISHOP, KNIGHT)
+ & ~ei.attackedBy[Them][ALL_PIECES];
if (undefendedMinors)
- score += more_than_one(undefendedMinors) ? UndefendedMinorPenalty * 2
- : UndefendedMinorPenalty;
+ score += UndefendedMinor;
// Enemy pieces not defended by a pawn and under our attack
weakEnemies = pos.pieces(Them)
& ~ei.attackedBy[Them][PAWN]
- & ei.attackedBy[Us][0];
-
- if (!weakEnemies)
- return score;
+ & ei.attackedBy[Us][ALL_PIECES];
// Add bonus according to type of attacked enemy piece and to the
// type of attacking piece, from knights to queens. Kings are not
// considered because are already 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))
- score += ThreatBonus[pt1][pt2];
- }
+ if (weakEnemies)
+ 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))
+ score += Threat[pt1][pt2];
+ }
+
+ if (Trace)
+ Tracing::scores[Us][THREAT] = score;
+
return score;
}
Score score = mobility = SCORE_ZERO;
// Do not include in mobility squares protected by enemy pawns or occupied by our pieces
- const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces(Us));
+ const Bitboard mobilityArea = ~(ei.attackedBy[Them][PAWN] | pos.pieces(Us, PAWN, KING));
score += evaluate_pieces<KNIGHT, Us, Trace>(pos, ei, mobility, mobilityArea);
score += evaluate_pieces<BISHOP, Us, Trace>(pos, ei, mobility, mobilityArea);
score += evaluate_pieces<QUEEN, Us, Trace>(pos, ei, mobility, mobilityArea);
// 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];
+ ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
+ | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
+ | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING];
+ if (Trace)
+ Tracing::scores[Us][MOBILITY] = apply_weight(mobility, Weights[Mobility]);
+
return score;
}
{
// Find the attacked squares around the king which has no defenders
// apart from the king itself
- undefended = ei.attackedBy[Them][0] & ei.attackedBy[Us][KING];
+ undefended = ei.attackedBy[Them][ALL_PIECES] & ei.attackedBy[Us][KING];
undefended &= ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT]
| ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
| ei.attackedBy[Us][QUEEN]);
// Initialize the 'attackUnits' variable, which is used later on as an
- // index to the KingDangerTable[] array. The initial value is based on
- // the number and types of the enemy's attacking pieces, the number of
+ // index to the KingDanger[] array. The initial value is based on the
+ // number and types of the enemy's attacking pieces, the number of
// attacked and undefended squares around our king, the square of the
// king, and the quality of the pawn shelter.
attackUnits = std::min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
+ 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount<Max15>(undefended))
- + InitKingDanger[relative_square(Us, ksq)]
+ + KingExposed[relative_square(Us, ksq)]
- mg_value(score) / 32;
// Analyse enemy's safe queen contact checks. First find undefended
b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT]
| ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]);
if (b)
- attackUnits += QueenContactCheckBonus
+ attackUnits += QueenContactCheck
* popcount<Max15>(b)
* (Them == pos.side_to_move() ? 2 : 1);
}
b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT]
| ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]);
if (b)
- attackUnits += RookContactCheckBonus
+ attackUnits += RookContactCheck
* popcount<Max15>(b)
* (Them == pos.side_to_move() ? 2 : 1);
}
// Analyse enemy's safe distance checks for sliders and knights
- safe = ~(pos.pieces(Them) | ei.attackedBy[Us][0]);
+ safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]);
b1 = pos.attacks_from<ROOK>(ksq) & safe;
b2 = pos.attacks_from<BISHOP>(ksq) & safe;
// Enemy queen safe checks
b = (b1 | b2) & ei.attackedBy[Them][QUEEN];
if (b)
- attackUnits += QueenCheckBonus * popcount<Max15>(b);
+ attackUnits += QueenCheck * popcount<Max15>(b);
// Enemy rooks safe checks
b = b1 & ei.attackedBy[Them][ROOK];
if (b)
- attackUnits += RookCheckBonus * popcount<Max15>(b);
+ attackUnits += RookCheck * popcount<Max15>(b);
// Enemy bishops safe checks
b = b2 & ei.attackedBy[Them][BISHOP];
if (b)
- attackUnits += BishopCheckBonus * popcount<Max15>(b);
+ attackUnits += BishopCheck * popcount<Max15>(b);
// Enemy knights safe checks
b = pos.attacks_from<KNIGHT>(ksq) & ei.attackedBy[Them][KNIGHT] & safe;
if (b)
- attackUnits += KnightCheckBonus * popcount<Max15>(b);
+ attackUnits += KnightCheck * popcount<Max15>(b);
- // To index KingDangerTable[] attackUnits must be in [0, 99] range
+ // To index KingDanger[] attackUnits must be in [0, 99] range
attackUnits = std::min(99, std::max(0, attackUnits));
- // Finally, extract the king danger score from the KingDangerTable[]
+ // Finally, extract the king danger score from the KingDanger[]
// array and subtract the score from evaluation. Set also margins[]
// value that will be used for pruning because this value can sometimes
// be very big, and so capturing a single attacking piece can therefore
// result in a score change far bigger than the value of the captured piece.
- score -= KingDangerTable[Us == Search::RootColor][attackUnits];
- margins[Us] += mg_value(KingDangerTable[Us == Search::RootColor][attackUnits]);
+ score -= KingDanger[Us == Search::RootColor][attackUnits];
+ margins[Us] += mg_value(KingDanger[Us == Search::RootColor][attackUnits]);
}
if (Trace)
- TracedScores[Us][KING] = score;
+ Tracing::scores[Us][KING] = score;
return score;
}
// evaluate_passed_pawns<>() evaluates the passed pawns of the given color
- template<Color Us>
+ template<Color Us, bool Trace>
Score evaluate_passed_pawns(const Position& pos, EvalInfo& ei) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
b = ei.pi->passed_pawns(Us);
- if (!b)
- return SCORE_ZERO;
-
- do {
+ while (b)
+ {
Square s = pop_lsb(&b);
assert(pos.pawn_is_passed(Us, s));
int rr = r * (r - 1);
// Base bonus based on rank
- Value mbonus = Value(20 * rr);
- Value ebonus = Value(10 * (rr + r + 1));
+ Value mbonus = Value(17 * rr);
+ Value ebonus = Value(7 * (rr + r + 1));
if (rr)
{
if (pos.is_empty(blockSq))
{
squaresToQueen = forward_bb(Us, s);
- defendedSquares = squaresToQueen & ei.attackedBy[Us][0];
+ defendedSquares = squaresToQueen & ei.attackedBy[Us][ALL_PIECES];
// If there is an enemy rook or queen attacking the pawn from behind,
// add all X-ray attacks by the rook or queen. Otherwise consider only
// the squares in the pawn's path attacked or occupied by the enemy.
- if ( (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN))
- && (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from<ROOK>(s)))
+ if (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from<ROOK>(s))
unsafeSquares = squaresToQueen;
else
- unsafeSquares = squaresToQueen & (ei.attackedBy[Them][0] | pos.pieces(Them));
+ unsafeSquares = squaresToQueen & (ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them));
- // If there aren't enemy attacks or pieces along the path to queen give
- // huge bonus. Even bigger if we protect the pawn's path.
- if (!unsafeSquares)
- ebonus += Value(rr * (squaresToQueen == defendedSquares ? 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(rr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8));
+ // If there aren't enemy attacks huge bonus, a bit smaller if at
+ // least block square is not attacked, otherwise smallest bonus.
+ int k = !unsafeSquares ? 15 : !(unsafeSquares & blockSq) ? 9 : 3;
+
+ // Big bonus if the path to queen is fully defended, a bit less
+ // if at least block square is defended.
+ if (defendedSquares == squaresToQueen)
+ k += 6;
+
+ else if (defendedSquares & blockSq)
+ k += (unsafeSquares & defendedSquares) == unsafeSquares ? 4 : 2;
+
+ mbonus += Value(k * rr), ebonus += Value(k * rr);
}
} // rr != 0
}
score += make_score(mbonus, ebonus);
- } while (b);
+ }
+
+ if (Trace)
+ Tracing::scores[Us][PASSED] = apply_weight(score, Weights[PassedPawns]);
// Add the scores to the middle game and endgame eval
return apply_weight(score, Weights[PassedPawns]);
// Compute plies to queening and check direct advancement
movesToGo = rank_distance(s, queeningSquare) - int(relative_rank(c, s) == RANK_2);
oppMovesToGo = square_distance(pos.king_square(~c), queeningSquare) - int(c != pos.side_to_move());
- pathDefended = ((ei.attackedBy[c][0] & queeningPath) == queeningPath);
+ pathDefended = ((ei.attackedBy[c][ALL_PIECES] & queeningPath) == queeningPath);
if (movesToGo >= oppMovesToGo && !pathDefended)
continue;
Bitboard safe = SpaceMask[Us]
& ~pos.pieces(Us, PAWN)
& ~ei.attackedBy[Them][PAWN]
- & (ei.attackedBy[Us][0] | ~ei.attackedBy[Them][0]);
+ & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]);
// Find all squares which are at most three squares behind some friendly pawn
Bitboard behind = pos.pieces(Us, PAWN);
return Value((result + GrainSize / 2) & ~(GrainSize - 1));
}
+ // apply_weight() weights score v by score w trying to prevent overflow
+ 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);
+ }
// weight_option() computes the value of an evaluation weight, by combining
// two UCI-configurable weights (midgame and endgame) with an internal weight.
}
- // A couple of little helpers used by tracing code, to_cp() converts a value to
- // a double in centipawns scale, trace_add() stores white and black scores.
+ // Tracing functions definitions
double to_cp(Value v) { return double(v) / double(PawnValueMg); }
- void trace_add(int idx, Score wScore, Score bScore) {
+ void Tracing::add(int idx, Score wScore, Score bScore) {
- TracedScores[WHITE][idx] = wScore;
- TracedScores[BLACK][idx] = bScore;
+ scores[WHITE][idx] = wScore;
+ scores[BLACK][idx] = bScore;
}
+ void Tracing::row(const char* name, int idx) {
- // trace_row() is an helper function used by tracing code to register the
- // values of a single evaluation term.
-
- void trace_row(const char* name, int idx) {
-
- Score wScore = TracedScores[WHITE][idx];
- Score bScore = TracedScores[BLACK][idx];
+ Score wScore = scores[WHITE][idx];
+ Score bScore = scores[BLACK][idx];
switch (idx) {
case PST: case IMBALANCE: case PAWN: case UNSTOPPABLE: case TOTAL:
- TraceStream << std::setw(20) << name << " | --- --- | --- --- | "
- << std::setw(6) << to_cp(mg_value(wScore)) << " "
- << std::setw(6) << to_cp(eg_value(wScore)) << " \n";
+ stream << std::setw(20) << name << " | --- --- | --- --- | "
+ << std::setw(6) << to_cp(mg_value(wScore)) << " "
+ << std::setw(6) << to_cp(eg_value(wScore)) << " \n";
break;
default:
- TraceStream << std::setw(20) << name << " | " << std::noshowpos
- << std::setw(5) << to_cp(mg_value(wScore)) << " "
- << std::setw(5) << to_cp(eg_value(wScore)) << " | "
- << std::setw(5) << to_cp(mg_value(bScore)) << " "
- << std::setw(5) << to_cp(eg_value(bScore)) << " | "
- << std::showpos
- << std::setw(6) << to_cp(mg_value(wScore - bScore)) << " "
- << std::setw(6) << to_cp(eg_value(wScore - bScore)) << " \n";
+ stream << std::setw(20) << name << " | " << std::noshowpos
+ << std::setw(5) << to_cp(mg_value(wScore)) << " "
+ << std::setw(5) << to_cp(eg_value(wScore)) << " | "
+ << std::setw(5) << to_cp(mg_value(bScore)) << " "
+ << std::setw(5) << to_cp(eg_value(bScore)) << " | "
+ << std::showpos
+ << std::setw(6) << to_cp(mg_value(wScore - bScore)) << " "
+ << std::setw(6) << to_cp(eg_value(wScore - bScore)) << " \n";
}
}
+
+ std::string Tracing::do_trace(const Position& pos) {
+
+ Search::RootColor = pos.side_to_move();
+
+ stream.str("");
+ stream << std::showpoint << std::showpos << std::fixed << std::setprecision(2);
+ memset(scores, 0, 2 * (TOTAL + 1) * sizeof(Score));
+
+ Value margin;
+ do_evaluate<true>(pos, margin);
+
+ std::string totals = stream.str();
+ stream.str("");
+
+ stream << std::setw(21) << "Eval term " << "| White | Black | Total \n"
+ << " | MG EG | MG EG | MG EG \n"
+ << "---------------------+-------------+-------------+---------------\n";
+
+ row("Material, PST, Tempo", PST);
+ row("Material imbalance", IMBALANCE);
+ row("Pawns", PAWN);
+ row("Knights", KNIGHT);
+ row("Bishops", BISHOP);
+ row("Rooks", ROOK);
+ row("Queens", QUEEN);
+ row("Mobility", MOBILITY);
+ row("King safety", KING);
+ row("Threats", THREAT);
+ row("Passed pawns", PASSED);
+ row("Unstoppable pawns", UNSTOPPABLE);
+ row("Space", SPACE);
+
+ stream << "---------------------+-------------+-------------+---------------\n";
+ row("Total", TOTAL);
+ stream << totals;
+
+ return stream.str();
+ }
}
projects / stockfish / blobdiff