bool useNNUE;
string eval_file_loaded = "None";
- /// init_NNUE() 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.
/// We search the given network in three locations: internally (the default
/// in the engine directory. Distro packagers may define the DEFAULT_NNUE_DIRECTORY
/// variable to have the engine search in a special directory in their distro.
- void init_NNUE() {
+ void NNUE::init() {
useNNUE = Options["Use NNUE"];
if (!useNNUE)
}
}
- /// verify_NNUE() verifies that the last net used was loaded successfully
- void verify_NNUE() {
+ /// NNUE::verify() verifies that the last net used was loaded successfully
+ void NNUE::verify() {
string eval_file = string(Options["EvalFile"]);
// 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}
+ {}, {}, {803, 1292}, {639, 974}, {1087, 1878}, {759, 1132}
};
#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,-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(-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) }
+ { S(-62,-79), S(-53,-57), S(-12,-31), S( -3,-17), S( 3, 7), S( 12, 13), // Knight
+ S( 21, 16), S( 28, 21), S( 37, 26) },
+ { S(-47,-59), S(-20,-25), S( 14, -8), S( 29, 12), S( 39, 21), S( 53, 40), // Bishop
+ S( 53, 56), S( 60, 58), S( 62, 65), S( 69, 72), S( 78, 78), S( 83, 87),
+ S( 91, 88), S( 96, 98) },
+ { S(-61,-82), S(-20,-17), S( 2, 23) ,S( 3, 40), S( 4, 72), S( 11,100), // Rook
+ S( 22,104), S( 31,120), S( 39,134), S(40 ,138), S( 41,158), S( 47,163),
+ S( 59,168), S( 60,169), S( 64,173) },
+ { S(-29,-49), S(-16,-29), S( -8, -8), S( -8, 17), S( 18, 39), S( 25, 54), // Queen
+ S( 23, 59), S( 37, 73), S( 41, 76), S( 54, 95), S( 65, 95) ,S( 68,101),
+ S( 69,124), S( 70,128), S( 70,132), S( 70,133) ,S( 71,136), S( 72,140),
+ S( 74,147), S( 76,149), S( 90,153), S(104,169), S(105,171), S(106,171),
+ S(112,178), S(114,185), S(114,187), S(119,221) }
+ };
+
+ // 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(1, 8), S(3, 7)
};
// KingProtector[knight/bishop] contains penalty for each distance unit to own king
// 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) };
+ constexpr Score Outpost[] = { S(56, 34), S(31, 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)
+ S(0, 0), S(9, 28), S(15, 31), S(17, 39), S(64, 70), S(171, 177), S(277, 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) };
+ constexpr Score RookOnFile[] = { S(19, 7), S(48, 27) };
// 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(57, 41), S(77, 56), S(88, 119), S(79, 161)
+ S(0, 0), S(5, 32), S(55, 41), S(77, 56), S(89, 119), S(79, 162)
};
constexpr Score ThreatByRook[PIECE_TYPE_NB] = {
- S(0, 0), S(3, 46), S(37, 68), S(42, 60), S(0, 38), S(58, 41)
+ S(0, 0), S(3, 44), S(37, 68), S(42, 60), S(0, 39), S(58, 43)
};
// 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 ReachableOutpost = S( 31, 22);
constexpr Score RestrictedPiece = S( 7, 7);
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);
// 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)
+ score -= BishopPawns[edge_distance(file_of(s))] * pos.pawns_on_same_color_squares(Us, s)
* (!(attackedBy[Us][PAWN] & s) + popcount(blocked & CenterFiles));
// Penalty for all enemy pawns x-rayed
if (Pt == ROOK)
{
- // Bonus for rook on the same file as a queen
- if (file_bb(s) & pos.pieces(QUEEN))
- score += RookOnQueenFile;
-
// Bonus for rook on an open or semi-open file
if (pos.is_on_semiopen_file(Us, s))
score += RookOnFile[pos.is_on_semiopen_file(Them, s)];
int kingFlankAttack = popcount(b1) + popcount(b2);
int kingFlankDefense = popcount(b3);
- kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them]
- + 185 * popcount(kingRing[Us] & weak)
- + 148 * popcount(unsafeChecks)
- + 98 * popcount(pos.blockers_for_king(Us))
- + 69 * kingAttacksCount[Them]
- + 3 * kingFlankAttack * kingFlankAttack / 8
- + mg_value(mobility[Them] - mobility[Us])
- - 873 * !pos.count<QUEEN>(Them)
- - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING])
- - 6 * mg_value(score) / 8
- - 4 * kingFlankDefense
- + 37;
+ kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them] // (~10 Elo)
+ + 185 * popcount(kingRing[Us] & weak) // (~15 Elo)
+ + 148 * popcount(unsafeChecks) // (~4 Elo)
+ + 98 * popcount(pos.blockers_for_king(Us)) // (~2 Elo)
+ + 69 * kingAttacksCount[Them] // (~0.5 Elo)
+ + 3 * kingFlankAttack * kingFlankAttack / 8 // (~0.5 Elo)
+ + mg_value(mobility[Them] - mobility[Us]) // (~0.5 Elo)
+ - 873 * !pos.count<QUEEN>(Them) // (~24 Elo)
+ - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING]) // (~5 Elo)
+ - 6 * mg_value(score) / 8 // (~8 Elo)
+ - 4 * kingFlankDefense // (~5 Elo)
+ + 37; // (~0.5 Elo)
// Transform the kingDanger units into a Score, and subtract it from the evaluation
if (kingDanger > 100)
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::min(sf, 36 + 7 * pos.count<PAWN>(strongSide)) - 4 * !pawnsOnBothFlanks;
+
+ sf -= 4 * !pawnsOnBothFlanks;
}
// Interpolate between the middlegame and (scaled by 'sf') endgame score
Value Eval::evaluate(const Position& pos) {
- bool classical = !Eval::useNNUE
- || abs(eg_value(pos.psq_score())) * 16 > NNUEThreshold1 * (16 + pos.rule50_count());
- Value v = classical ? Evaluation<NO_TRACE>(pos).value()
- : NNUE::evaluate(pos) * 5 / 4 + Tempo;
+ Value v;
- if (classical && Eval::useNNUE && abs(v) * 16 < NNUEThreshold2 * (16 + pos.rule50_count()))
- v = NNUE::evaluate(pos) * 5 / 4 + Tempo;
+ if (!Eval::useNNUE)
+ v = Evaluation<NO_TRACE>(pos).value();
+ else
+ {
+ // Scale and shift NNUE for compatibility with search and classical evaluation
+ auto adjusted_NNUE = [&](){
+ int mat = pos.non_pawn_material() + PieceValue[MG][PAWN] * pos.count<PAWN>();
+ return NNUE::evaluate(pos) * (720 + 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));
+
+ v = classical ? 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
+ && (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();
+ }
// Damp down the evaluation linearly when shuffling
v = v * (100 - pos.rule50_count()) / 100;