/*
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) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2004-2020 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 <algorithm>
#include <cassert>
+#include <cstdlib>
#include <cstring> // For std::memset
#include <iomanip>
#include <sstream>
+#include <iostream>
#include "bitboard.h"
#include "evaluate.h"
#include "material.h"
#include "pawns.h"
#include "thread.h"
+#include "uci.h"
+
+namespace Eval {
+
+ bool useNNUE;
+ std::string eval_file_loaded="None";
+
+ void init_NNUE() {
+
+ useNNUE = Options["Use NNUE"];
+ std::string eval_file = std::string(Options["EvalFile"]);
+ if (useNNUE && eval_file_loaded != eval_file)
+ if (Eval::NNUE::load_eval_file(eval_file))
+ eval_file_loaded = eval_file;
+ }
+
+ void verify_NNUE() {
+
+ std::string eval_file = std::string(Options["EvalFile"]);
+ if (useNNUE && eval_file_loaded != eval_file)
+ {
+ std::cerr << "Use of NNUE evaluation, but the file " << eval_file << " was not loaded successfully. "
+ << "These network evaluation parameters must be available, compatible with this version of the code. "
+ << "The UCI option EvalFile might need to specify the full path, including the directory/folder name, to the file." << std::endl;
+ std::exit(EXIT_FAILURE);
+ }
+
+ if (useNNUE)
+ sync_cout << "info string NNUE evaluation using " << eval_file << " enabled." << sync_endl;
+ else
+ sync_cout << "info string classical evaluation enabled." << sync_endl;
+ }
+}
namespace Trace {
enum Tracing { NO_TRACE, TRACE };
enum Term { // The first 8 entries are reserved for PieceType
- MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, INITIATIVE, TOTAL, TERM_NB
+ MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, WINNABLE, TOTAL, TERM_NB
};
Score scores[TERM_NB][COLOR_NB];
std::ostream& operator<<(std::ostream& os, Term t) {
- if (t == MATERIAL || t == IMBALANCE || t == INITIATIVE || t == TOTAL)
+ if (t == MATERIAL || t == IMBALANCE || t == WINNABLE || t == TOTAL)
os << " ---- ----" << " | " << " ---- ----";
else
os << scores[t][WHITE] << " | " << scores[t][BLACK];
namespace {
// Threshold for lazy and space evaluation
- constexpr Value LazyThreshold = Value(1400);
+ constexpr Value LazyThreshold1 = Value(1400);
+ constexpr Value LazyThreshold2 = Value(1300);
constexpr Value SpaceThreshold = Value(12222);
+ constexpr Value NNUEThreshold = Value(520);
// KingAttackWeights[PieceType] contains king attack weights by piece type
constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
- // Penalties for enemy's safe checks
- constexpr int QueenSafeCheck = 780;
- constexpr int RookSafeCheck = 1078;
- constexpr int BishopSafeCheck = 635;
- constexpr int KnightSafeCheck = 790;
+ // SafeCheck[PieceType][single/multiple] contains safe check bonus by piece type,
+ // higher if multiple safe checks are possible for that piece type.
+ constexpr int SafeCheck[][2] = {
+ {}, {}, {792, 1283}, {645, 967}, {1084, 1897}, {772, 1119}
+ };
#define S(mg, eg) make_score(mg, eg)
// 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(-62,-81), S(-53,-56), S(-12,-30), S( -4,-14), S( 3, 8), S( 13, 15), // Knight
- S( 22, 23), S( 28, 27), S( 33, 33) },
+ { S(-62,-81), S(-53,-56), S(-12,-31), S( -4,-16), S( 3, 5), S( 13, 11), // Knight
+ S( 22, 17), S( 28, 20), S( 33, 25) },
{ S(-48,-59), S(-20,-23), S( 16, -3), S( 26, 13), S( 38, 24), S( 51, 42), // Bishop
S( 55, 54), S( 63, 57), S( 63, 65), S( 68, 73), S( 81, 78), S( 81, 86),
S( 91, 88), S( 98, 97) },
{ S(-60,-78), S(-20,-17), S( 2, 23), S( 3, 39), S( 3, 70), S( 11, 99), // Rook
S( 22,103), S( 31,121), S( 40,134), S( 40,139), S( 41,158), S( 48,164),
S( 57,168), S( 57,169), S( 62,172) },
- { S(-34,-36), S(-15,-21), S(-10, -1), S(-10, 22), S( 20, 41), S( 23, 56), // Queen
+ { S(-30,-48), S(-12,-30), S( -8, -7), S( -9, 19), S( 20, 40), S( 23, 55), // Queen
S( 23, 59), S( 35, 75), S( 38, 78), S( 53, 96), S( 64, 96), S( 65,100),
S( 65,121), S( 66,127), S( 67,131), S( 67,133), S( 72,136), S( 72,141),
S( 77,147), S( 79,150), S( 93,151), S(108,168), S(108,168), S(108,171),
S(110,182), S(114,182), S(114,192), S(116,219) }
};
+ // KingProtector[knight/bishop] contains penalty for each distance unit to own king
+ constexpr Score KingProtector[] = { S(8, 9), S(6, 9) };
+
+ // Outpost[knight/bishop] contains bonuses for each knight or bishop occupying a
+ // pawn protected square on rank 4 to 6 which is also safe from a pawn attack.
+ constexpr Score Outpost[] = { S(56, 36), S(30, 23) };
+
+ // PassedRank[Rank] contains a bonus according to the rank of a passed pawn
+ constexpr Score PassedRank[RANK_NB] = {
+ S(0, 0), S(10, 28), S(17, 33), S(15, 41), S(62, 72), S(168, 177), S(276, 260)
+ };
+
// RookOnFile[semiopen/open] contains bonuses for each rook when there is
// no (friendly) pawn on the rook file.
constexpr Score RookOnFile[] = { S(19, 7), S(48, 29) };
S(0, 0), S(3, 46), S(37, 68), S(42, 60), S(0, 38), S(58, 41)
};
- // PassedRank[Rank] contains a bonus according to the rank of a passed pawn
- constexpr Score PassedRank[RANK_NB] = {
- S(0, 0), S(10, 28), S(17, 33), S(15, 41), S(62, 72), S(168, 177), S(276, 260)
- };
-
// Assorted bonuses and penalties
+ constexpr Score BadOutpost = S( -7, 36);
+ constexpr Score BishopOnKingRing = S( 24, 0);
constexpr Score BishopPawns = S( 3, 7);
+ constexpr Score BishopXRayPawns = S( 4, 5);
constexpr Score CorneredBishop = S( 50, 50);
constexpr Score FlankAttacks = S( 8, 0);
constexpr Score Hanging = S( 69, 36);
- constexpr Score KingProtector = S( 7, 8);
constexpr Score KnightOnQueen = S( 16, 11);
constexpr Score LongDiagonalBishop = S( 45, 0);
constexpr Score MinorBehindPawn = S( 18, 3);
- constexpr Score Outpost = S( 30, 21);
constexpr Score PassedFile = S( 11, 8);
constexpr Score PawnlessFlank = S( 17, 95);
+ constexpr Score ReachableOutpost = S( 31, 22);
constexpr Score RestrictedPiece = S( 7, 7);
- constexpr Score RookOnQueenFile = S( 5, 9);
- constexpr Score SliderOnQueen = S( 59, 18);
+ constexpr Score RookOnKingRing = S( 16, 0);
+ constexpr Score RookOnQueenFile = S( 6, 11);
+ constexpr Score SliderOnQueen = S( 60, 18);
constexpr Score ThreatByKing = S( 24, 89);
constexpr Score ThreatByPawnPush = S( 48, 39);
constexpr Score ThreatBySafePawn = S(173, 94);
constexpr Score TrappedRook = S( 55, 13);
- constexpr Score WeakQueen = S( 51, 14);
- constexpr Score WeakQueenProtection = S( 15, 0);
+ constexpr Score WeakQueenProtection = S( 14, 0);
+ constexpr Score WeakQueen = S( 56, 15);
+
#undef S
template<Color Us> Score threats() const;
template<Color Us> Score passed() const;
template<Color Us> Score space() const;
- ScaleFactor scale_factor(Value eg) const;
- Score initiative(Score score) const;
+ Value winnable(Score score) const;
const Position& pos;
Material::Entry* me;
// Evaluation::initialize() computes king and pawn attacks, and the king ring
// bitboard for a given color. This is done at the beginning of the evaluation.
+
template<Tracing T> template<Color Us>
void Evaluation<T>::initialize() {
mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pos.blockers_for_king(Us) | pe->pawn_attacks(Them));
// Initialize attackedBy[] for king and pawns
- attackedBy[Us][KING] = pos.attacks_from<KING>(ksq);
+ attackedBy[Us][KING] = attacks_bb<KING>(ksq);
attackedBy[Us][PAWN] = pe->pawn_attacks(Us);
attackedBy[Us][ALL_PIECES] = attackedBy[Us][KING] | attackedBy[Us][PAWN];
attackedBy2[Us] = dblAttackByPawn | (attackedBy[Us][KING] & attackedBy[Us][PAWN]);
// Init our king safety tables
Square s = make_square(Utility::clamp(file_of(ksq), FILE_B, FILE_G),
Utility::clamp(rank_of(ksq), RANK_2, RANK_7));
- kingRing[Us] = PseudoAttacks[KING][s] | s;
+ kingRing[Us] = attacks_bb<KING>(s) | s;
kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them));
kingAttacksCount[Them] = kingAttackersWeight[Them] = 0;
// Evaluation::pieces() scores pieces of a given color and type
+
template<Tracing T> template<Color Us, PieceType Pt>
Score Evaluation<T>::pieces() {
// Find attacked squares, including x-ray attacks for bishops and rooks
b = Pt == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(QUEEN))
: Pt == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(QUEEN) ^ pos.pieces(Us, ROOK))
- : pos.attacks_from<Pt>(s);
+ : attacks_bb<Pt>(s, pos.pieces());
if (pos.blockers_for_king(Us) & s)
- b &= LineBB[pos.square<KING>(Us)][s];
+ b &= line_bb(pos.square<KING>(Us), s);
attackedBy2[Us] |= attackedBy[Us][ALL_PIECES] & b;
attackedBy[Us][Pt] |= b;
kingAttacksCount[Us] += popcount(b & attackedBy[Them][KING]);
}
+ else if (Pt == ROOK && (file_bb(s) & kingRing[Them]))
+ score += RookOnKingRing;
+
+ else if (Pt == BISHOP && (attacks_bb<BISHOP>(s, pos.pieces(PAWN)) & kingRing[Them]))
+ score += BishopOnKingRing;
+
int mob = popcount(b & mobilityArea[Us]);
mobility[Us] += MobilityBonus[Pt - 2][mob];
if (Pt == BISHOP || Pt == KNIGHT)
{
- // Bonus if piece is on an outpost square or can reach one
- bb = OutpostRanks & attackedBy[Us][PAWN] & ~pe->pawn_attacks_span(Them);
- if (bb & s)
- score += Outpost * (Pt == KNIGHT ? 2 : 1);
-
+ // Bonus if the piece is on an outpost square or can reach one
+ // Reduced bonus for knights (BadOutpost) if few relevant targets
+ bb = OutpostRanks & (attackedBy[Us][PAWN] | shift<Down>(pos.pieces(PAWN)))
+ & ~pe->pawn_attacks_span(Them);
+ Bitboard targets = pos.pieces(Them) & ~pos.pieces(PAWN);
+
+ if ( Pt == KNIGHT
+ && bb & s & ~CenterFiles // on a side outpost
+ && !(b & targets) // no relevant attacks
+ && (!more_than_one(targets & (s & QueenSide ? QueenSide : KingSide))))
+ score += BadOutpost;
+ else if (bb & s)
+ score += Outpost[Pt == BISHOP];
else if (Pt == KNIGHT && bb & b & ~pos.pieces(Us))
- score += Outpost;
+ score += ReachableOutpost;
// Bonus for a knight or bishop shielded by pawn
if (shift<Down>(pos.pieces(PAWN)) & s)
score += MinorBehindPawn;
// Penalty if the piece is far from the king
- score -= KingProtector * distance(pos.square<KING>(Us), s);
+ score -= KingProtector[Pt == BISHOP] * distance(pos.square<KING>(Us), s);
if (Pt == BISHOP)
{
- // Penalty according to number of pawns on the same color square as the
+ // Penalty according to the number of our pawns on the same color square as the
// bishop, bigger when the center files are blocked with pawns and smaller
// when the bishop is outside the pawn chain.
Bitboard blocked = pos.pieces(Us, PAWN) & shift<Down>(pos.pieces());
score -= BishopPawns * pos.pawns_on_same_color_squares(Us, s)
* (!(attackedBy[Us][PAWN] & s) + popcount(blocked & CenterFiles));
+ // Penalty for all enemy pawns x-rayed
+ score -= BishopXRayPawns * popcount(attacks_bb<BISHOP>(s) & pos.pieces(Them, PAWN));
+
// Bonus for bishop on a long diagonal which can "see" both center squares
if (more_than_one(attacks_bb<BISHOP>(s, pos.pieces(PAWN)) & Center))
score += LongDiagonalBishop;
// Evaluation::king() assigns bonuses and penalties to a king of a given color
+
template<Tracing T> template<Color Us>
Score Evaluation<T>::king() const {
b2 = attacks_bb<BISHOP>(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN));
// Enemy rooks checks
- rookChecks = b1 & safe & attackedBy[Them][ROOK];
+ rookChecks = b1 & attackedBy[Them][ROOK] & safe;
if (rookChecks)
- kingDanger += more_than_one(rookChecks) ? RookSafeCheck * 3/2
- : RookSafeCheck;
+ kingDanger += SafeCheck[ROOK][more_than_one(rookChecks)];
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;
+ // Enemy queen safe checks: count them only if the checks are from squares from
+ // which opponent cannot give a rook check, because rook checks are more valuable.
+ queenChecks = (b1 | b2) & attackedBy[Them][QUEEN] & safe
+ & ~(attackedBy[Us][QUEEN] | rookChecks);
if (queenChecks)
- kingDanger += more_than_one(queenChecks) ? QueenSafeCheck * 3/2
- : 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
+ kingDanger += SafeCheck[QUEEN][more_than_one(queenChecks)];
+
+ // Enemy bishops checks: count them only if they are from squares from which
+ // opponent cannot give a queen check, because queen checks are more valuable.
+ bishopChecks = b2 & attackedBy[Them][BISHOP] & safe
& ~queenChecks;
if (bishopChecks)
- kingDanger += more_than_one(bishopChecks) ? BishopSafeCheck * 3/2
- : BishopSafeCheck;
+ kingDanger += SafeCheck[BISHOP][more_than_one(bishopChecks)];
+
else
unsafeChecks |= b2 & attackedBy[Them][BISHOP];
// Enemy knights checks
- knightChecks = pos.attacks_from<KNIGHT>(ksq) & attackedBy[Them][KNIGHT];
+ knightChecks = attacks_bb<KNIGHT>(ksq) & attackedBy[Them][KNIGHT];
if (knightChecks & safe)
- kingDanger += more_than_one(knightChecks & safe) ? KnightSafeCheck * 3/2
- : KnightSafeCheck;
+ kingDanger += SafeCheck[KNIGHT][more_than_one(knightChecks & safe)];
else
unsafeChecks |= knightChecks;
b2 = b1 & attackedBy2[Them];
b3 = attackedBy[Us][ALL_PIECES] & KingFlank[file_of(ksq)] & Camp;
- int kingFlankAttack = popcount(b1) + popcount(b2);
+ int kingFlankAttack = popcount(b1) + popcount(b2);
int kingFlankDefense = popcount(b3);
kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them]
// Evaluation::threats() assigns bonuses according to the types of the
// attacking and the attacked pieces.
+
template<Tracing T> template<Color Us>
Score Evaluation<T>::threats() const {
// Bonus for threats on the next moves against enemy queen
if (pos.count<QUEEN>(Them) == 1)
{
+ bool queenImbalance = pos.count<QUEEN>() == 1;
+
Square s = pos.square<QUEEN>(Them);
- safe = mobilityArea[Us] & ~stronglyProtected;
+ safe = mobilityArea[Us]
+ & ~pos.pieces(Us, PAWN)
+ & ~stronglyProtected;
- b = attackedBy[Us][KNIGHT] & pos.attacks_from<KNIGHT>(s);
+ b = attackedBy[Us][KNIGHT] & attacks_bb<KNIGHT>(s);
- score += KnightOnQueen * popcount(b & safe);
+ score += KnightOnQueen * popcount(b & safe) * (1 + queenImbalance);
- b = (attackedBy[Us][BISHOP] & pos.attacks_from<BISHOP>(s))
- | (attackedBy[Us][ROOK ] & pos.attacks_from<ROOK >(s));
+ b = (attackedBy[Us][BISHOP] & attacks_bb<BISHOP>(s, pos.pieces()))
+ | (attackedBy[Us][ROOK ] & attacks_bb<ROOK >(s, pos.pieces()));
- score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]);
+ score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]) * (1 + queenImbalance);
}
if (T)
return std::min(distance(pos.square<KING>(c), s), 5);
};
- Bitboard b, bb, squaresToQueen, unsafeSquares, candidatePassers, leverable;
+ Bitboard b, bb, squaresToQueen, unsafeSquares, blockedPassers, helpers;
Score score = SCORE_ZERO;
b = pe->passed_pawns(Us);
- candidatePassers = b & shift<Down>(pos.pieces(Them, PAWN));
- if (candidatePassers)
+ blockedPassers = b & shift<Down>(pos.pieces(Them, PAWN));
+ if (blockedPassers)
{
- // Can we lever the blocker of a candidate passer?
- leverable = shift<Up>(pos.pieces(Us, PAWN))
- & ~pos.pieces(Them)
- & (~attackedBy2[Them] | attackedBy[Us][ALL_PIECES])
- & (~(attackedBy[Them][KNIGHT] | attackedBy[Them][BISHOP])
- | (attackedBy[Us ][KNIGHT] | attackedBy[Us ][BISHOP]));
-
- // Remove candidate otherwise
- b &= ~candidatePassers
- | shift<WEST>(leverable)
- | shift<EAST>(leverable);
+ helpers = shift<Up>(pos.pieces(Us, PAWN))
+ & ~pos.pieces(Them)
+ & (~attackedBy2[Them] | attackedBy[Us][ALL_PIECES]);
+
+ // Remove blocked candidate passers that don't have help to pass
+ b &= ~blockedPassers
+ | shift<WEST>(helpers)
+ | shift<EAST>(helpers);
}
while (b)
}
- // Evaluation::space() computes the space evaluation for a given side. The
- // space evaluation is a simple bonus based on the number of safe squares
- // available for minor pieces on the central four files on ranks 2--4. Safe
- // squares one, two or three squares behind a friendly pawn are counted
- // twice. Finally, the space bonus is multiplied by a weight. The aim is to
- // improve play on game opening.
+ // Evaluation::space() computes a space evaluation for a given side, aiming to improve game
+ // play in the opening. It is based on the number of safe squares on the 4 central files
+ // on ranks 2 to 4. Completely safe squares behind a friendly pawn are counted twice.
+ // Finally, the space bonus is multiplied by a weight which decreases according to occupancy.
template<Tracing T> template<Color Us>
Score Evaluation<T>::space() const {
+ // Early exit if, for example, both queens or 6 minor pieces have been exchanged
if (pos.non_pawn_material() < SpaceThreshold)
return SCORE_ZERO;
}
- // Evaluation::initiative() computes the initiative correction value
- // for the position. It is a second order bonus/malus based on the
- // known attacking/defending status of the players.
+ // Evaluation::winnable() adjusts the midgame and endgame score components, based on
+ // the known attacking/defending status of the players. The final value is derived
+ // by interpolation from the midgame and endgame values.
template<Tracing T>
- Score Evaluation<T>::initiative(Score score) const {
+ Value Evaluation<T>::winnable(Score score) const {
int outflanking = distance<File>(pos.square<KING>(WHITE), pos.square<KING>(BLACK))
- distance<Rank>(pos.square<KING>(WHITE), pos.square<KING>(BLACK));
bool almostUnwinnable = outflanking < 0
&& !pawnsOnBothFlanks;
- bool infiltration = rank_of(pos.square<KING>(WHITE)) > RANK_4
- || rank_of(pos.square<KING>(BLACK)) < RANK_5;
+ bool infiltration = rank_of(pos.square<KING>(WHITE)) > RANK_4
+ || rank_of(pos.square<KING>(BLACK)) < RANK_5;
// Compute the initiative bonus for the attacking side
int complexity = 9 * pe->passed_count()
- + 1
1 * pos.count<PAWN>()
+ + 1
2 * pos.count<PAWN>()
+ 9 * outflanking
+ 21 * pawnsOnBothFlanks
+ 24 * infiltration
// Now apply the bonus: note that we find the attacking side by extracting the
// sign of the midgame or endgame values, and that we carefully cap the bonus
// so that the midgame and endgame scores do not change sign after the bonus.
- int u = ((mg > 0) - (mg < 0)) * std::max(std::min(complexity + 50, 0), -abs(mg));
+ int u = ((mg > 0) - (mg < 0)) * Utility::clamp(complexity + 50, -abs(mg), 0);
int v = ((eg > 0) - (eg < 0)) * std::max(complexity, -abs(eg));
- if (T)
- Trace::add(INITIATIVE, make_score(u, v));
-
- return make_score(u, v);
- }
-
-
- // Evaluation::scale_factor() computes the scale factor for the winning side
-
- template<Tracing T>
- ScaleFactor Evaluation<T>::scale_factor(Value eg) const {
+ mg += u;
+ eg += v;
+ // Compute the scale factor for the winning side
Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
int sf = me->scale_factor(pos, strongSide);
- // If scale is not already specific, scale down the endgame via general heuristics
+ // If scale factor is not already specific, scale down via general heuristics
if (sf == SCALE_FACTOR_NORMAL)
{
if (pos.opposite_bishops())
{
if ( pos.non_pawn_material(WHITE) == BishopValueMg
&& pos.non_pawn_material(BLACK) == BishopValueMg)
- sf = 22;
+ sf = 18 + 4 * popcount(pe->passed_pawns(strongSide));
else
sf = 22 + 3 * pos.count<ALL_PIECES>(strongSide);
}
+ else if ( pos.non_pawn_material(WHITE) == RookValueMg
+ && pos.non_pawn_material(BLACK) == RookValueMg
+ && pos.count<PAWN>(strongSide) - pos.count<PAWN>(~strongSide) <= 1
+ && bool(KingSide & pos.pieces(strongSide, PAWN)) != bool(QueenSide & pos.pieces(strongSide, PAWN))
+ && (attacks_bb<KING>(pos.square<KING>(~strongSide)) & pos.pieces(~strongSide, PAWN)))
+ sf = 36;
+ else if (pos.count<QUEEN>() == 1)
+ sf = 37 + 3 * (pos.count<QUEEN>(WHITE) == 1 ? pos.count<BISHOP>(BLACK) + pos.count<KNIGHT>(BLACK)
+ : pos.count<BISHOP>(WHITE) + pos.count<KNIGHT>(WHITE));
else
sf = std::min(sf, 36 + 7 * pos.count<PAWN>(strongSide));
+ }
- sf = std::max(0, sf - (pos.rule50_count() - 12) / 4);
+ // Interpolate between the middlegame and (scaled by 'sf') endgame score
+ v = mg * int(me->game_phase())
+ + eg * int(PHASE_MIDGAME - me->game_phase()) * ScaleFactor(sf) / SCALE_FACTOR_NORMAL;
+ v /= PHASE_MIDGAME;
+
+ if (T)
+ {
+ Trace::add(WINNABLE, make_score(u, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL - eg_value(score)));
+ Trace::add(TOTAL, make_score(mg, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL));
}
- return ScaleFactor(sf);
+ return Value(v);
}
score += pe->pawn_score(WHITE) - pe->pawn_score(BLACK);
// Early exit if score is high
- Value v = (mg_value(score) + eg_value(score)) / 2;
- if (abs(v) > LazyThreshold + pos.non_pawn_material() / 64)
- return pos.side_to_move() == WHITE ? v : -v;
+ auto lazy_skip = [&](Value lazyThreshold) {
+ return abs(mg_value(score) + eg_value(score)) / 2 > lazyThreshold + pos.non_pawn_material() / 64;
+ };
- // Main evaluation begins here
+ if (lazy_skip(LazyThreshold1))
+ goto make_v;
+ // Main evaluation begins here
initialize<WHITE>();
initialize<BLACK>();
- // Pieces should be evaluated first (populate attack tables)
+ // Pieces evaluated first (also populates attackedBy, attackedBy2).
+ // Note that the order of evaluation of the terms is left unspecified.
score += pieces<WHITE, KNIGHT>() - pieces<BLACK, KNIGHT>()
+ pieces<WHITE, BISHOP>() - pieces<BLACK, BISHOP>()
+ pieces<WHITE, ROOK >() - pieces<BLACK, ROOK >()
score += mobility[WHITE] - mobility[BLACK];
+ // More complex interactions that require fully populated attack bitboards
score += king< WHITE>() - king< BLACK>()
- + threats<WHITE>() - threats<BLACK>()
- + passed< WHITE>() - passed< BLACK>()
- + space< WHITE>() - space< BLACK>();
+ + passed< WHITE>() - passed< BLACK>();
- score += initiative(score);
+ if (lazy_skip(LazyThreshold2))
+ goto make_v;
- // Interpolate between a middlegame and a (scaled by 'sf') endgame score
- ScaleFactor sf = scale_factor(eg_value(score));
- v = mg_value(score) * int(me->game_phase())
- + eg_value(score) * int(PHASE_MIDGAME - me->game_phase()) * sf / SCALE_FACTOR_NORMAL;
+ score += threats<WHITE>() - threats<BLACK>()
+ + space< WHITE>() - space< BLACK>();
- v /= PHASE_MIDGAME;
+make_v:
+ // Derive single value from mg and eg parts of score
+ Value v = winnable(score);
// In case of tracing add all remaining individual evaluation terms
if (T)
Trace::add(IMBALANCE, me->imbalance());
Trace::add(PAWN, pe->pawn_score(WHITE), pe->pawn_score(BLACK));
Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]);
- Trace::add(TOTAL, score);
}
- return (pos.side_to_move() == WHITE ? v : -v) + Tempo; // Side to move point of view
+ // Evaluation grain
+ v = (v / 16) * 16;
+
+ // Side to move point of view
+ v = (pos.side_to_move() == WHITE ? v : -v) + Tempo;
+
+ // Damp down the evaluation linearly when shuffling
+ v = v * (100 - pos.rule50_count()) / 100;
+
+ return v;
}
} // namespace
/// evaluation of the position from the point of view of the side to move.
Value Eval::evaluate(const Position& pos) {
+
+ if (Eval::useNNUE)
+ {
+ Value v = eg_value(pos.psq_score());
+ // Take NNUE eval only on balanced positions
+ if (abs(v) < NNUEThreshold)
+ return NNUE::evaluate(pos) + Tempo;
+ }
return Evaluation<NO_TRACE>(pos).value();
}
-
/// trace() is like evaluate(), but instead of returning a value, it returns
/// a string (suitable for outputting to stdout) that contains the detailed
/// descriptions and values of each evaluation term. Useful for debugging.
+/// Trace scores are from white's point of view
std::string Eval::trace(const Position& pos) {
if (pos.checkers())
- return "Total evaluation: none (in check)";
+ return "Final evaluation: none (in check)";
- std::memset(scores, 0, sizeof(scores));
+ std::stringstream ss;
+ ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2);
- pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
+ Value v;
- Value v = Evaluation<TRACE>(pos).value();
+ if (Eval::useNNUE)
+ {
+ v = NNUE::evaluate(pos);
+ }
+ else
+ {
+ std::memset(scores, 0, sizeof(scores));
+
+ pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
+
+ v = Evaluation<TRACE>(pos).value();
+
+ ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2)
+ << " Term | White | Black | Total \n"
+ << " | MG EG | MG EG | MG EG \n"
+ << " ------------+-------------+-------------+------------\n"
+ << " Material | " << Term(MATERIAL)
+ << " Imbalance | " << Term(IMBALANCE)
+ << " Pawns | " << Term(PAWN)
+ << " Knights | " << Term(KNIGHT)
+ << " Bishops | " << Term(BISHOP)
+ << " Rooks | " << Term(ROOK)
+ << " Queens | " << Term(QUEEN)
+ << " Mobility | " << Term(MOBILITY)
+ << " King safety | " << Term(KING)
+ << " Threats | " << Term(THREAT)
+ << " Passed | " << Term(PASSED)
+ << " Space | " << Term(SPACE)
+ << " Winnable | " << Term(WINNABLE)
+ << " ------------+-------------+-------------+------------\n"
+ << " Total | " << Term(TOTAL);
+ }
- v = pos.side_to_move() == WHITE ? v : -v; // Trace scores are from white's point of view
+ v = pos.side_to_move() == WHITE ? v : -v;
- std::stringstream ss;
- ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2)
- << " Term | White | Black | Total \n"
- << " | MG EG | MG EG | MG EG \n"
- << " ------------+-------------+-------------+------------\n"
- << " Material | " << Term(MATERIAL)
- << " Imbalance | " << Term(IMBALANCE)
- << " Pawns | " << Term(PAWN)
- << " Knights | " << Term(KNIGHT)
- << " Bishops | " << Term(BISHOP)
- << " Rooks | " << Term(ROOK)
- << " Queens | " << Term(QUEEN)
- << " Mobility | " << Term(MOBILITY)
- << " King safety | " << Term(KING)
- << " Threats | " << Term(THREAT)
- << " Passed | " << Term(PASSED)
- << " Space | " << Term(SPACE)
- << " Initiative | " << Term(INITIATIVE)
- << " ------------+-------------+-------------+------------\n"
- << " Total | " << Term(TOTAL);
-
- ss << "\nTotal evaluation: " << to_cp(v) << " (white side)\n";
+ ss << "\nFinal evaluation: " << to_cp(v) << " (white side)\n";
return ss.str();
}
projects / stockfish / blobdiff