X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=11d4c687dfe7066ee1abda9b2d933c70f34b24c6;hp=d67b95cae96413746d77176e1dcf9bcb31c73b98;hb=b8e5092d07aaf736894d7d80b19d0185a1789084;hpb=e551afbab7767ddf79d33c24f8307a8cb291e3cd diff --git a/src/material.cpp b/src/material.cpp index d67b95ca..11d4c687 100644 --- a/src/material.cpp +++ b/src/material.cpp @@ -2,7 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -18,7 +18,6 @@ along with this program. If not, see . */ -#include // For std::min #include #include // For std::memset @@ -31,18 +30,18 @@ namespace { // Polynomial material imbalance parameters - const int QuadraticOurs[][PIECE_TYPE_NB] = { + constexpr int QuadraticOurs[][PIECE_TYPE_NB] = { // OUR PIECES // pair pawn knight bishop rook queen - {1667 }, // Bishop pair - { 40, 0 }, // Pawn - { 32, 255, -3 }, // Knight OUR PIECES + {1438 }, // Bishop pair + { 40, 38 }, // Pawn + { 32, 255, -62 }, // Knight OUR PIECES { 0, 104, 4, 0 }, // Bishop - { -26, -2, 47, 105, -149 }, // Rook - {-185, 24, 122, 137, -134, 0 } // Queen + { -26, -2, 47, 105, -208 }, // Rook + {-189, 24, 117, 133, -134, -6 } // Queen }; - const int QuadraticTheirs[][PIECE_TYPE_NB] = { + constexpr int QuadraticTheirs[][PIECE_TYPE_NB] = { // THEIR PIECES // pair pawn knight bishop rook queen { 0 }, // Bishop pair @@ -50,18 +49,7 @@ namespace { { 9, 63, 0 }, // Knight OUR PIECES { 59, 65, 42, 0 }, // Bishop { 46, 39, 24, -24, 0 }, // Rook - { 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 + { 97, 100, -42, 137, 268, 0 } // Queen }; // Endgame evaluation and scaling functions are accessed directly and not through @@ -79,16 +67,14 @@ namespace { && pos.non_pawn_material(us) >= RookValueMg; } - bool is_KBPsKs(const Position& pos, Color us) { + bool is_KBPsK(const Position& pos, Color us) { return pos.non_pawn_material(us) == BishopValueMg - && pos.count(us) == 1 && pos.count(us) >= 1; } bool is_KQKRPs(const Position& pos, Color us) { return !pos.count(us) && pos.non_pawn_material(us) == QueenValueMg - && pos.count(us) == 1 && pos.count(~us) == 1 && pos.count(~us) >= 1; } @@ -98,11 +84,11 @@ namespace { template int imbalance(const int pieceCount[][PIECE_TYPE_NB]) { - const Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr 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]) @@ -117,10 +103,6 @@ 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; } @@ -147,7 +129,7 @@ Entry* probe(const Position& pos) { 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)); + Value npm = clamp(npm_w + npm_b, EndgameLimit, MidgameLimit); // Map total non-pawn material into [PHASE_ENDGAME, PHASE_MIDGAME] e->gamePhase = Phase(((npm - EndgameLimit) * PHASE_MIDGAME) / (MidgameLimit - EndgameLimit)); @@ -155,10 +137,10 @@ Entry* probe(const Position& pos) { // Let's look if we have a specialized evaluation function for this particular // material configuration. Firstly we look for a fixed configuration one, then // for a generic one if the previous search failed. - if ((e->evaluationFunction = pos.this_thread()->endgames.probe(key)) != nullptr) + if ((e->evaluationFunction = Endgames::probe(key)) != nullptr) return e; - for (Color c = WHITE; c <= BLACK; ++c) + for (Color c : { WHITE, BLACK }) if (is_KXK(pos, c)) { e->evaluationFunction = &EvaluateKXK[c]; @@ -167,9 +149,9 @@ Entry* probe(const Position& pos) { // OK, we didn't find any special evaluation function for the current material // configuration. Is there a suitable specialized scaling function? - EndgameBase* sf; + const auto* sf = Endgames::probe(key); - if ((sf = pos.this_thread()->endgames.probe(key)) != nullptr) + if (sf) { e->scalingFunction[sf->strongSide] = sf; // Only strong color assigned return e; @@ -178,9 +160,9 @@ Entry* probe(const Position& pos) { // We didn't find any specialized scaling function, so fall back on generic // ones that refer to more than one material distribution. Note that in this // case we don't return after setting the function. - for (Color c = WHITE; c <= BLACK; ++c) + for (Color c : { WHITE, BLACK }) { - if (is_KBPsKs(pos, c)) + if (is_KBPsK(pos, c)) e->scalingFunction[c] = &ScaleKBPsK[c]; else if (is_KQKRPs(pos, c)) @@ -221,22 +203,16 @@ Entry* probe(const Position& pos) { e->factor[BLACK] = uint8_t(npm_b < RookValueMg ? SCALE_FACTOR_DRAW : npm_w <= BishopValueMg ? 4 : 14); - if (pos.count(WHITE) == 1 && npm_w - npm_b <= BishopValueMg) - e->factor[WHITE] = (uint8_t) SCALE_FACTOR_ONEPAWN; - - if (pos.count(BLACK) == 1 && npm_b - npm_w <= BishopValueMg) - e->factor[BLACK] = (uint8_t) SCALE_FACTOR_ONEPAWN; - // Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder // for the bishop pair "extended piece", which allows us to be more flexible // in defining bishop pair bonuses. - const int PieceCount[COLOR_NB][PIECE_TYPE_NB] = { + const int pieceCount[COLOR_NB][PIECE_TYPE_NB] = { { pos.count(WHITE) > 1, pos.count(WHITE), pos.count(WHITE), pos.count(WHITE) , pos.count(WHITE), pos.count(WHITE) }, { pos.count(BLACK) > 1, pos.count(BLACK), pos.count(BLACK), pos.count(BLACK) , pos.count(BLACK), pos.count(BLACK) } }; - e->value = int16_t((imbalance(PieceCount) - imbalance(PieceCount)) / 16); + e->value = int16_t((imbalance(pieceCount) - imbalance(pieceCount)) / 16); return e; }