/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+ Copyright (C) 2004-2022 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
// Note that this does not work in Microsoft Visual Studio.
#if !defined(_MSC_VER) && !defined(NNUE_EMBEDDING_OFF)
INCBIN(EmbeddedNNUE, EvalFileDefaultName);
- constexpr bool gHasEmbeddedNet = true;
#else
- constexpr bool gHasEmbeddedNet = false;
const unsigned char gEmbeddedNNUEData[1] = {0x0};
const unsigned char *const gEmbeddedNNUEEnd = &gEmbeddedNNUEData[1];
const unsigned int gEmbeddedNNUESize = 1;
namespace Eval {
bool useNNUE;
- string eval_file_loaded = "None";
+ string currentEvalFileName = "None";
/// NNUE::init() tries to load a NNUE network at startup time, or when the engine
/// receives a UCI command "setoption name EvalFile value nn-[a-z0-9]{12}.nnue"
return;
string eval_file = string(Options["EvalFile"]);
+ if (eval_file.empty())
+ eval_file = EvalFileDefaultName;
#if defined(DEFAULT_NNUE_DIRECTORY)
#define stringify2(x) #x
#endif
for (string directory : dirs)
- if (eval_file_loaded != eval_file)
+ if (currentEvalFileName != eval_file)
{
if (directory != "<internal>")
{
ifstream stream(directory + eval_file, ios::binary);
if (load_eval(eval_file, stream))
- eval_file_loaded = eval_file;
+ currentEvalFileName = eval_file;
}
if (directory == "<internal>" && eval_file == EvalFileDefaultName)
MemoryBuffer buffer(const_cast<char*>(reinterpret_cast<const char*>(gEmbeddedNNUEData)),
size_t(gEmbeddedNNUESize));
+ (void) gEmbeddedNNUEEnd; // Silence warning on unused variable
istream stream(&buffer);
if (load_eval(eval_file, stream))
- eval_file_loaded = eval_file;
+ currentEvalFileName = eval_file;
}
}
}
- void NNUE::export_net() {
- if constexpr (gHasEmbeddedNet) {
- ofstream stream(EvalFileDefaultName, std::ios_base::binary);
- stream.write(reinterpret_cast<const char*>(gEmbeddedNNUEData), gEmbeddedNNUESize);
- } else {
- sync_cout << "No embedded network file." << sync_endl;
- }
- }
-
/// NNUE::verify() verifies that the last net used was loaded successfully
void NNUE::verify() {
string eval_file = string(Options["EvalFile"]);
+ if (eval_file.empty())
+ eval_file = EvalFileDefaultName;
- if (useNNUE && eval_file_loaded != eval_file)
+ if (useNNUE && currentEvalFileName != eval_file)
{
- UCI::OptionsMap defaults;
- UCI::init(defaults);
string msg1 = "If the UCI option \"Use NNUE\" is set to true, network evaluation parameters compatible with the engine must be available.";
string msg2 = "The option is set to true, but the network file " + eval_file + " was not loaded successfully.";
string msg3 = "The UCI option EvalFile might need to specify the full path, including the directory name, to the network file.";
- string msg4 = "The default net can be downloaded from: https://tests.stockfishchess.org/api/nn/" + string(defaults["EvalFile"]);
+ string msg4 = "The default net can be downloaded from: https://tests.stockfishchess.org/api/nn/" + std::string(EvalFileDefaultName);
string msg5 = "The engine will be terminated now.";
sync_cout << "info string ERROR: " << msg1 << sync_endl;
else
os << scores[t][WHITE] << " | " << scores[t][BLACK];
- os << " | " << scores[t][WHITE] - scores[t][BLACK] << "\n";
+ os << " | " << scores[t][WHITE] - scores[t][BLACK] << " |\n";
return os;
}
}
namespace {
// Threshold for lazy and space evaluation
- constexpr Value LazyThreshold1 = Value(1565);
- constexpr Value LazyThreshold2 = Value(1102);
- constexpr Value SpaceThreshold = Value(11551);
- constexpr Value NNUEThreshold1 = Value(682);
- constexpr Value NNUEThreshold2 = Value(176);
+ constexpr Value LazyThreshold1 = Value(3631);
+ constexpr Value LazyThreshold2 = Value(2084);
+ constexpr Value SpaceThreshold = Value(11551);
// KingAttackWeights[PieceType] contains king attack weights by piece type
- constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
+ constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 76, 46, 45, 14 };
// 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] = {
- {}, {}, {803, 1292}, {639, 974}, {1087, 1878}, {759, 1132}
+ {}, {}, {805, 1292}, {650, 984}, {1071, 1886}, {730, 1128}
};
#define S(mg, eg) make_score(mg, eg)
// BishopPawns[distance from edge] contains a file-dependent penalty for pawns on
// squares of the same color as our bishop.
constexpr Score BishopPawns[int(FILE_NB) / 2] = {
- S(3, 8), S(3, 9), S(2, 8), S(3, 8)
+ S(3, 8), S(3, 9), S(2, 7), S(3, 7)
};
// KingProtector[knight/bishop] contains penalty for each distance unit to own king
- constexpr Score KingProtector[] = { S(8, 9), S(6, 9) };
+ constexpr Score KingProtector[] = { S(9, 9), S(7, 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(57, 38), S(31, 24) };
+ constexpr Score Outpost[] = { S(54, 34), S(31, 25) };
// PassedRank[Rank] contains a bonus according to the rank of a passed pawn
constexpr Score PassedRank[RANK_NB] = {
- S(0, 0), S(7, 27), S(16, 32), S(17, 40), S(64, 71), S(170, 174), S(278, 262)
+ S(0, 0), S(2, 38), S(15, 36), S(22, 50), S(64, 81), S(166, 184), S(284, 269)
};
constexpr Score RookOnClosedFile = S(10, 5);
- constexpr Score RookOnOpenFile[] = { S(19, 6), S(47, 26) };
+ constexpr Score RookOnOpenFile[] = { S(18, 8), S(49, 26) };
// 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(5, 32), S(55, 41), S(77, 56), S(89, 119), S(79, 162)
+ S(0, 0), S(6, 37), S(64, 50), S(82, 57), S(103, 130), S(81, 163)
};
constexpr Score ThreatByRook[PIECE_TYPE_NB] = {
- S(0, 0), S(3, 44), S(37, 68), S(42, 60), S(0, 39), S(58, 43)
+ S(0, 0), S(3, 44), S(36, 71), S(44, 59), S(0, 39), S(60, 39)
};
constexpr Value CorneredBishop = Value(50);
// Assorted bonuses and penalties
- constexpr Score UncontestedOutpost = S( 1, 10);
+ constexpr Score UncontestedOutpost = S( 0, 10);
constexpr Score BishopOnKingRing = S( 24, 0);
constexpr Score BishopXRayPawns = S( 4, 5);
constexpr Score FlankAttacks = S( 8, 0);
- constexpr Score Hanging = S( 69, 36);
+ constexpr Score Hanging = S( 72, 40);
constexpr Score KnightOnQueen = S( 16, 11);
constexpr Score LongDiagonalBishop = S( 45, 0);
constexpr Score MinorBehindPawn = S( 18, 3);
- 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 PassedFile = S( 13, 8);
+ constexpr Score PawnlessFlank = S( 19, 97);
+ constexpr Score ReachableOutpost = S( 33, 19);
+ constexpr Score RestrictedPiece = S( 6, 7);
constexpr Score RookOnKingRing = S( 16, 0);
- constexpr Score SliderOnQueen = S( 60, 18);
- constexpr Score ThreatByKing = S( 24, 89);
+ constexpr Score SliderOnQueen = S( 62, 21);
+ constexpr Score ThreatByKing = S( 24, 87);
constexpr Score ThreatByPawnPush = S( 48, 39);
- constexpr Score ThreatBySafePawn = S(173, 94);
+ constexpr Score ThreatBySafePawn = S(167, 99);
constexpr Score TrappedRook = S( 55, 13);
constexpr Score WeakQueenProtection = S( 14, 0);
- constexpr Score WeakQueen = S( 56, 15);
+ constexpr Score WeakQueen = S( 57, 19);
#undef S
Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
int sf = me->scale_factor(pos, strongSide);
- // If scale factor is not already specific, scale down via general heuristics
+ // If scale factor is not already specific, scale up/down via general heuristics
if (sf == SCALE_FACTOR_NORMAL)
{
if (pos.opposite_bishops())
// 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() + pos.this_thread()->contempt;
+ Score score = pos.psq_score() + me->imbalance() + pos.this_thread()->trend;
// Probe the pawn hash table
pe = Pawns::probe(pos);
// Early exit if score is high
auto lazy_skip = [&](Value lazyThreshold) {
- return abs(mg_value(score) + eg_value(score)) / 2 > lazyThreshold + pos.non_pawn_material() / 64;
+ return abs(mg_value(score) + eg_value(score)) > lazyThreshold
+ + std::abs(pos.this_thread()->bestValue) * 5 / 4
+ + pos.non_pawn_material() / 32;
};
if (lazy_skip(LazyThreshold1))
v = (v / 16) * 16;
// Side to move point of view
- v = (pos.side_to_move() == WHITE ? v : -v) + Tempo;
+ v = (pos.side_to_move() == WHITE ? v : -v);
return v;
}
-
- /// Fisher Random Chess: correction for cornered bishops, to fix chess960 play with NNUE
-
- Value fix_FRC(const Position& pos) {
-
- constexpr Bitboard Corners = 1ULL << SQ_A1 | 1ULL << SQ_H1 | 1ULL << SQ_A8 | 1ULL << SQ_H8;
-
- if (!(pos.pieces(BISHOP) & Corners))
- return VALUE_ZERO;
-
- int correction = 0;
-
- if ( pos.piece_on(SQ_A1) == W_BISHOP
- && pos.piece_on(SQ_B2) == W_PAWN)
- correction += !pos.empty(SQ_B3) ? -CorneredBishop * 4
- : -CorneredBishop * 3;
-
- if ( pos.piece_on(SQ_H1) == W_BISHOP
- && pos.piece_on(SQ_G2) == W_PAWN)
- correction += !pos.empty(SQ_G3) ? -CorneredBishop * 4
- : -CorneredBishop * 3;
-
- if ( pos.piece_on(SQ_A8) == B_BISHOP
- && pos.piece_on(SQ_B7) == B_PAWN)
- correction += !pos.empty(SQ_B6) ? CorneredBishop * 4
- : CorneredBishop * 3;
-
- if ( pos.piece_on(SQ_H8) == B_BISHOP
- && pos.piece_on(SQ_G7) == B_PAWN)
- correction += !pos.empty(SQ_G6) ? CorneredBishop * 4
- : CorneredBishop * 3;
-
- return pos.side_to_move() == WHITE ? Value(correction)
- : -Value(correction);
- }
-
} // namespace Eval
/// evaluate() is the evaluator for the outer world. It returns a static
/// evaluation of the position from the point of view of the side to move.
-Value Eval::evaluate(const Position& pos) {
+Value Eval::evaluate(const Position& pos, int* complexity) {
Value v;
-
- if (!Eval::useNNUE)
+ Color stm = pos.side_to_move();
+ Value psq = pos.psq_eg_stm();
+ // Deciding between classical and NNUE eval (~10 Elo): for high PSQ imbalance we use classical,
+ // but we switch to NNUE during long shuffling or with high material on the board.
+ bool useClassical = (pos.count<ALL_PIECES>() > 7)
+ && abs(psq) * 5 > (856 + pos.non_pawn_material() / 64) * (10 + pos.rule50_count());
+
+ // Deciding between classical and NNUE eval (~10 Elo): for high PSQ imbalance we use classical,
+ // but we switch to NNUE during long shuffling or with high material on the board.
+ if (!useNNUE || useClassical)
+ {
v = Evaluation<NO_TRACE>(pos).value();
- else
+ useClassical = abs(v) >= 297;
+ }
+
+ // If result of a classical evaluation is much lower than threshold fall back to NNUE
+ if (useNNUE && !useClassical)
{
- // Scale and shift NNUE for compatibility with search and classical evaluation
- auto adjusted_NNUE = [&]()
- {
- int material = pos.non_pawn_material() + 4 * PawnValueMg * pos.count<PAWN>();
- int scale = 580
- + material / 32
- - 4 * pos.rule50_count();
-
- Value nnue = NNUE::evaluate(pos) * scale / 1024 + Time.tempoNNUE;
-
- if (pos.is_chess960())
- nnue += fix_FRC(pos);
-
- return nnue;
- };
-
- // If there is PSQ imbalance we use the classical eval. We also introduce
- // a small probability of using the classical eval when PSQ imbalance is small.
- Value psq = Value(abs(eg_value(pos.psq_score())));
- int r50 = 16 + pos.rule50_count();
- bool largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50;
- bool classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB));
-
- // Use classical evaluation for really low piece endgames.
- // One critical case is the draw for bishop + A/H file pawn vs naked king.
- bool lowPieceEndgame = pos.non_pawn_material() == BishopValueMg
- || (pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2);
-
- v = classical || lowPieceEndgame ? Evaluation<NO_TRACE>(pos).value()
- : adjusted_NNUE();
-
- // If the classical eval is small and imbalance large, use NNUE nevertheless.
- // For the case of opposite colored bishops, switch to NNUE eval with small
- // probability if the classical eval is less than the threshold.
- if ( largePsq
- && !lowPieceEndgame
- && ( abs(v) * 16 < NNUEThreshold2 * r50
- || ( pos.opposite_bishops()
- && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
- && !(pos.this_thread()->nodes & 0xB))))
- v = adjusted_NNUE();
+ int nnueComplexity;
+ int scale = 1064 + 106 * pos.non_pawn_material() / 5120;
+ Value optimism = pos.this_thread()->optimism[stm];
+
+ Value nnue = NNUE::evaluate(pos, true, &nnueComplexity);
+ // Blend nnue complexity with (semi)classical complexity
+ nnueComplexity = (104 * nnueComplexity + 131 * abs(nnue - psq)) / 256;
+ if (complexity) // Return hybrid NNUE complexity to caller
+ *complexity = nnueComplexity;
+
+ optimism = optimism * (269 + nnueComplexity) / 256;
+ v = (nnue * scale + optimism * (scale - 754)) / 1024;
}
// Damp down the evaluation linearly when shuffling
- v = v * (100 - pos.rule50_count()) / 100;
+ v = v * (195 - pos.rule50_count()) / 211;
// Guarantee evaluation does not hit the tablebase range
v = std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1);
+ // When not using NNUE, return classical complexity to caller
+ if (complexity && (!useNNUE || useClassical))
+ *complexity = abs(v - psq);
+
return v;
}
/// 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) {
+std::string Eval::trace(Position& pos) {
if (pos.checkers())
return "Final evaluation: none (in check)";
std::memset(scores, 0, sizeof(scores));
- pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
+ // Reset any global variable used in eval
+ pos.this_thread()->depth = 0;
+ pos.this_thread()->trend = SCORE_ZERO;
+ pos.this_thread()->bestValue = VALUE_ZERO;
+ pos.this_thread()->optimism[WHITE] = VALUE_ZERO;
+ pos.this_thread()->optimism[BLACK] = VALUE_ZERO;
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);
+ << " Contributing terms for the classical eval:\n"
+ << "+------------+-------------+-------------+-------------+\n"
+ << "| 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)
+ << "+------------+-------------+-------------+-------------+\n";
- v = pos.side_to_move() == WHITE ? v : -v;
+ if (Eval::useNNUE)
+ ss << '\n' << NNUE::trace(pos) << '\n';
- ss << "\nClassical evaluation: " << to_cp(v) << " (white side)\n";
+ ss << std::showpoint << std::showpos << std::fixed << std::setprecision(2) << std::setw(15);
+ v = pos.side_to_move() == WHITE ? v : -v;
+ ss << "\nClassical evaluation " << to_cp(v) << " (white side)\n";
if (Eval::useNNUE)
{
- v = NNUE::evaluate(pos);
+ v = NNUE::evaluate(pos, false);
v = pos.side_to_move() == WHITE ? v : -v;
- ss << "\nNNUE evaluation: " << to_cp(v) << " (white side)\n";
+ ss << "NNUE evaluation " << to_cp(v) << " (white side)\n";
}
v = evaluate(pos);
v = pos.side_to_move() == WHITE ? v : -v;
- ss << "\nFinal evaluation: " << to_cp(v) << " (white side)\n";
+ ss << "Final evaluation " << to_cp(v) << " (white side)";
+ if (Eval::useNNUE)
+ ss << " [with scaled NNUE, hybrid, ...]";
+ ss << "\n";
return ss.str();
}
projects / stockfish / blobdiff