#include "misc.h"
#include "pawns.h"
#include "thread.h"
+#include "timeman.h"
#include "uci.h"
#include "incbin/incbin.h"
-// Macro to embed the default NNUE file data in the engine binary (using incbin.h, by Dale Weiler).
+// Macro to embed the default efficiently updatable neural network (NNUE) file
+// data in the engine binary (using incbin.h, by Dale Weiler).
// This macro invocation will declare the following three variables
// const unsigned char gEmbeddedNNUEData[]; // a pointer to the embedded data
// const unsigned char *const gEmbeddedNNUEEnd; // a marker to the end
// const unsigned int gEmbeddedNNUESize; // the size of the embedded file
-// Note that this does not work in Microsof Visual Studio.
+// Note that this does not work in Microsoft Visual Studio.
#if !defined(_MSC_VER) && !defined(NNUE_EMBEDDING_OFF)
INCBIN(EmbeddedNNUE, EvalFileDefaultName);
#else
using namespace std;
-using namespace Eval::NNUE;
+
+namespace Stockfish {
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
+ /// 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"
- /// The name of the nnue network is always retrieved from the EvalFile option.
+ /// The name of the NNUE network is always retrieved from the EvalFile option.
/// We search the given network in three locations: internally (the default
/// network may be embedded in the binary), in the active working directory and
/// in the engine directory. Distro packagers may define the DEFAULT_NNUE_DIRECTORY
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;
}
}
}
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(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 };
S(0, 0), S(3, 44), S(37, 68), S(42, 60), S(0, 39), S(58, 43)
};
+ constexpr Value CorneredBishop = Value(50);
+
// Assorted bonuses and penalties
constexpr Score UncontestedOutpost = S( 1, 10);
constexpr Score BishopOnKingRing = S( 24, 0);
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 KnightOnQueen = S( 16, 11);
attackedBy[Us][Pt] = 0;
- while (b1) {
- Square s = pop_lsb(&b1);
+ while (b1)
+ {
+ Square s = pop_lsb(b1);
// Find attacked squares, including x-ray attacks for bishops and rooks
b = Pt == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(QUEEN))
score += BishopOnKingRing;
int mob = popcount(b & mobilityArea[Us]);
-
mobility[Us] += MobilityBonus[Pt - 2][mob];
if (Pt == BISHOP || Pt == KNIGHT)
// Penalty if the piece is far from the king
score -= KingProtector[Pt == BISHOP] * distance(pos.square<KING>(Us), s);
- if (Pt == BISHOP)
+ if constexpr (Pt == BISHOP)
{
// 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
{
Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
if (pos.piece_on(s + d) == make_piece(Us, PAWN))
- score -= !pos.empty(s + d + pawn_push(Us)) ? CorneredBishop * 4
- : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2
- : CorneredBishop;
+ score -= !pos.empty(s + d + pawn_push(Us)) ? 4 * make_score(CorneredBishop, CorneredBishop)
+ : 3 * make_score(CorneredBishop, CorneredBishop);
}
}
}
- if (Pt == ROOK)
+ if constexpr (Pt == ROOK)
{
// Bonuses for rook on a (semi-)open or closed file
if (pos.is_on_semiopen_file(Us, s))
}
}
- if (Pt == QUEEN)
+ if constexpr (Pt == QUEEN)
{
// Penalty if any relative pin or discovered attack against the queen
Bitboard queenPinners;
score -= WeakQueen;
}
}
- if (T)
+ if constexpr (T)
Trace::add(Pt, Us, score);
return score;
// Penalty if king flank is under attack, potentially moving toward the king
score -= FlankAttacks * kingFlankAttack;
- if (T)
+ if constexpr (T)
Trace::add(KING, Us, score);
return score;
{
b = (defended | weak) & (attackedBy[Us][KNIGHT] | attackedBy[Us][BISHOP]);
while (b)
- score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(&b)))];
+ score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(b)))];
b = weak & attackedBy[Us][ROOK];
while (b)
- score += ThreatByRook[type_of(pos.piece_on(pop_lsb(&b)))];
+ score += ThreatByRook[type_of(pos.piece_on(pop_lsb(b)))];
if (weak & attackedBy[Us][KING])
score += ThreatByKing;
score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]) * (1 + queenImbalance);
}
- if (T)
+ if constexpr (T)
Trace::add(THREAT, Us, score);
return score;
while (b)
{
- Square s = pop_lsb(&b);
+ Square s = pop_lsb(b);
assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
score += bonus - PassedFile * edge_distance(file_of(s));
}
- if (T)
+ if constexpr (T)
Trace::add(PASSED, Us, score);
return score;
int weight = pos.count<ALL_PIECES>(Us) - 3 + std::min(pe->blocked_count(), 9);
Score score = make_score(bonus * weight * weight / 16, 0);
- if (T)
+ if constexpr (T)
Trace::add(SPACE, Us, score);
return score;
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())
+ eg * int(PHASE_MIDGAME - me->game_phase()) * ScaleFactor(sf) / SCALE_FACTOR_NORMAL;
v /= PHASE_MIDGAME;
- if (T)
+ if constexpr (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));
// 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))
Value v = winnable(score);
// In case of tracing add all remaining individual evaluation terms
- if (T)
+ if constexpr (T)
{
Trace::add(MATERIAL, pos.psq_score());
Trace::add(IMBALANCE, me->imbalance());
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;
}
-} // namespace
+
+ /// 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 -= CorneredBishop;
+
+ if ( pos.piece_on(SQ_H1) == W_BISHOP
+ && pos.piece_on(SQ_G2) == W_PAWN)
+ correction -= CorneredBishop;
+
+ if ( pos.piece_on(SQ_A8) == B_BISHOP
+ && pos.piece_on(SQ_B7) == B_PAWN)
+ correction += CorneredBishop;
+
+ if ( pos.piece_on(SQ_H8) == B_BISHOP
+ && pos.piece_on(SQ_G7) == B_PAWN)
+ correction += CorneredBishop;
+
+ return pos.side_to_move() == WHITE ? Value(5 * correction)
+ : -Value(5 * correction);
+ }
+
+} // namespace Eval
/// evaluate() is the evaluator for the outer world. It returns a static
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 mat = pos.non_pawn_material() + PawnValueMg * pos.count<PAWN>();
- return NNUE::evaluate(pos) * (679 + mat / 32) / 1024 + Tempo;
- };
-
- // If there is PSQ imbalance use classical eval, with small probability if it 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.
- // The most critical case is a bishop + A/H file pawn vs naked king draw.
- bool strongClassical = pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2;
-
- v = classical || strongClassical ? 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 && !strongClassical
- && ( 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 scale = 1049
+ + 8 * pos.count<PAWN>()
+ + 20 * pos.non_pawn_material() / 1024;
+
+ Value nnue = NNUE::evaluate(pos, true); // NNUE
+ Color stm = pos.side_to_move();
+ Value optimism = pos.this_thread()->optimism[stm];
+
+ 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();
}
+
+} // namespace Stockfish