X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=c0237e7cac7507f3442977d0ffc153c3058544ef;hp=e5b8ddf2ac819cf6b11a71926eab3946d6d26c36;hb=f6981b1321357866e7aff688572e1d0e1fe57c08;hpb=b48439e90643cb6f65f9e34d1421976883c12efc diff --git a/src/material.cpp b/src/material.cpp index e5b8ddf2..c0237e7c 100644 --- a/src/material.cpp +++ b/src/material.cpp @@ -53,9 +53,10 @@ namespace { { 101, 100, -37, 141, 268, 0 } // Queen }; - // PawnSet[pawn count] contains a bonus/malus indexed by number of pawns - const int PawnSet[] = { - 24, -32, 107, -51, 117, -9, -126, -21, 31 + // QueenMinorsImbalance[opp_minor_count] is applied when only one side has a queen. + // It contains a bonus/malus for the side with the queen. + const int QueenMinorsImbalance[13] = { + 31, -8, -15, -25, -5 }; // Endgame evaluation and scaling functions are accessed directly and not through @@ -94,9 +95,9 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); - int bonus = PawnSet[pieceCount[Us][PAWN]]; + int bonus = 0; - // Second-degree polynomial material imbalance by Tord Romstad + // Second-degree polynomial material imbalance, by Tord Romstad for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1) { if (!pieceCount[Us][pt1]) @@ -111,6 +112,10 @@ namespace { bonus += pieceCount[Us][pt1] * v; } + // Special handling of Queen vs. Minors + if (pieceCount[Us][QUEEN] == 1 && pieceCount[Them][QUEEN] == 0) + bonus += QueenMinorsImbalance[pieceCount[Them][KNIGHT] + pieceCount[Them][BISHOP]]; + return bonus; } @@ -134,7 +139,13 @@ Entry* probe(const Position& pos) { std::memset(e, 0, sizeof(Entry)); e->key = key; e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL; - e->gamePhase = pos.game_phase(); + + Value npm_w = pos.non_pawn_material(WHITE); + Value npm_b = pos.non_pawn_material(BLACK); + Value npm = std::max(EndgameLimit, std::min(npm_w + npm_b, MidgameLimit)); + + // Map total non-pawn material into [PHASE_ENDGAME, PHASE_MIDGAME] + e->gamePhase = Phase(((npm - EndgameLimit) * PHASE_MIDGAME) / (MidgameLimit - EndgameLimit)); // Let's look if we have a specialized evaluation function for this particular // material configuration. Firstly we look for a fixed configuration one, then @@ -155,7 +166,7 @@ Entry* probe(const Position& pos) { if ((sf = pos.this_thread()->endgames.probe(key)) != nullptr) { - e->scalingFunction[sf->strong_side()] = sf; // Only strong color assigned + e->scalingFunction[sf->strongSide] = sf; // Only strong color assigned return e; } @@ -171,9 +182,6 @@ Entry* probe(const Position& pos) { e->scalingFunction[c] = &ScaleKQKRPs[c]; } - Value npm_w = pos.non_pawn_material(WHITE); - Value npm_b = pos.non_pawn_material(BLACK); - if (npm_w + npm_b == VALUE_ZERO && pos.pieces(PAWN)) // Only pawns on the board { if (!pos.count(BLACK))