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)
istream stream(&buffer);
if (load_eval(eval_file, stream))
- eval_file_loaded = eval_file;
+ currentEvalFileName = eval_file;
}
}
}
- /// NNUE::export_net() exports the currently loaded network to a file
- void NNUE::export_net(const std::optional<std::string>& filename) {
- std::string actualFilename;
-
- if (filename.has_value())
- actualFilename = filename.value();
- else
- {
- if (eval_file_loaded != EvalFileDefaultName)
- {
- sync_cout << "Failed to export a net. A non-embedded net can only be saved if the filename is specified." << sync_endl;
- return;
- }
- actualFilename = EvalFileDefaultName;
- }
-
- ofstream stream(actualFilename, std::ios_base::binary);
-
- if (save_eval(stream))
- sync_cout << "Network saved successfully to " << actualFilename << "." << sync_endl;
- else
- sync_cout << "Failed to export a net." << 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(800);
+ constexpr Value LazyThreshold1 = Value(3130);
+ constexpr Value LazyThreshold2 = Value(2204);
+ 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 };
// 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))
if ( pos.piece_on(SQ_A1) == W_BISHOP
&& pos.piece_on(SQ_B2) == W_PAWN)
- correction += !pos.empty(SQ_B3) ? -CorneredBishop * 4
- : -CorneredBishop * 3;
+ correction -= CorneredBishop;
if ( pos.piece_on(SQ_H1) == W_BISHOP
&& pos.piece_on(SQ_G2) == W_PAWN)
- correction += !pos.empty(SQ_G3) ? -CorneredBishop * 4
- : -CorneredBishop * 3;
+ correction -= CorneredBishop;
if ( pos.piece_on(SQ_A8) == B_BISHOP
&& pos.piece_on(SQ_B7) == B_PAWN)
- correction += !pos.empty(SQ_B6) ? CorneredBishop * 4
- : CorneredBishop * 3;
+ correction += CorneredBishop;
if ( pos.piece_on(SQ_H8) == B_BISHOP
&& pos.piece_on(SQ_G7) == B_PAWN)
- correction += !pos.empty(SQ_G6) ? CorneredBishop * 4
- : CorneredBishop * 3;
+ correction += CorneredBishop;
- return pos.side_to_move() == WHITE ? Value(correction)
- : -Value(correction);
+ return pos.side_to_move() == WHITE ? Value(5 * correction)
+ : -Value(5 * correction);
}
} // namespace Eval
Value v;
- if (!Eval::useNNUE)
- v = Evaluation<NO_TRACE>(pos).value();
+ // Deciding between classical and NNUE eval: for high PSQ imbalance we use classical,
+ // but we switch to NNUE during long shuffling or with high material on the board.
+
+ if ( !useNNUE
+ || abs(eg_value(pos.psq_score())) * 5 > (850 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count()))
+ v = Evaluation<NO_TRACE>(pos).value(); // classical
else
{
- // Scale and shift NNUE for compatibility with search and classical evaluation
- auto adjusted_NNUE = [&]()
- {
-
- int scale = 903 + 28 * pos.count<PAWN>() + 28 * pos.non_pawn_material() / 1024;
-
- Value nnue = NNUE::evaluate(pos, true) * scale / 1024;
-
- if (pos.is_chess960())
- nnue += fix_FRC(pos);
+ int scale = 1049
+ + 8 * pos.count<PAWN>()
+ + 20 * pos.non_pawn_material() / 1024;
- return nnue;
- };
+ Value nnue = NNUE::evaluate(pos, true); // NNUE
+ Color stm = pos.side_to_move();
+ Value optimism = pos.this_thread()->optimism[stm];
- // If there is PSQ imbalance we use the classical eval.
- 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;
-
- v = largePsq ? Evaluation<NO_TRACE>(pos).value() // classical
- : adjusted_NNUE(); // NNUE
+ v = (nnue + optimism) * scale / 1024 - optimism;
+ if (pos.is_chess960())
+ v += fix_FRC(pos);
}
// Damp down the evaluation linearly when shuffling
- v = v * (100 - pos.rule50_count()) / 100;
+ v = v * (207 - pos.rule50_count()) / 207;
// 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);
/// 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()->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();
}