X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=94967c25eac588043e0730eabc2c0da5a4a16745;hp=0ee0a6eb840bf2b0eabe740b0d1faf13d50e4ee5;hb=5f12069cbfc882fdf989d04618ad9c33e603c419;hpb=431c3ac485386cc10413fc8a3c7d338dcc71602d diff --git a/src/endgame.cpp b/src/endgame.cpp index 0ee0a6eb..94967c25 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, 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 @@ -82,8 +82,7 @@ namespace { // Get the material key of Position out of the given endgame key code // like "KBPKN". The trick here is to first forge an ad-hoc FEN string - // and then let a Position object do the work for us. Note that the - // FEN string could correspond to an illegal position. + // and then let a Position object do the work for us. Key key(const string& code, Color c) { assert(code.length() > 0 && code.length() < 8); @@ -94,8 +93,8 @@ namespace { std::transform(sides[c].begin(), sides[c].end(), sides[c].begin(), tolower); - string fen = sides[0] + char('0' + int(8 - code.length())) - + sides[1] + "/8/8/8/8/8/8/8 w - - 0 10"; + string fen = sides[0] + char(8 - sides[0].length() + '0') + "/8/8/8/8/8/8/" + + sides[1] + char(8 - sides[1].length() + '0') + " w - - 0 10"; return Position(fen, false, NULL).material_key(); } @@ -118,7 +117,6 @@ Endgames::Endgames() { add("KRKN"); add("KQKP"); add("KQKR"); - add("KBBKN"); add("KNPK"); add("KNPKB"); @@ -242,7 +240,7 @@ Value Endgame::operator()(const Position& pos) const { Square rsq = relative_square(strongSide, pos.list(strongSide)[0]); Square psq = relative_square(strongSide, pos.list(weakSide)[0]); - Square queeningSq = file_of(psq) | RANK_1; + Square queeningSq = make_square(file_of(psq), RANK_1); Value result; // If the stronger side's king is in front of the pawn, it's a win @@ -348,32 +346,8 @@ Value Endgame::operator()(const Position& pos) const { } -/// KBB vs KN. This is almost always a win. We try to push the enemy king to a corner -/// and away from his knight. For a reference of this difficult endgame see: -/// en.wikipedia.org/wiki/Chess_endgame#Effect_of_tablebases_on_endgame_theory - -template<> -Value Endgame::operator()(const Position& pos) const { - - assert(verify_material(pos, strongSide, 2 * BishopValueMg, 0)); - assert(verify_material(pos, weakSide, KnightValueMg, 0)); - - Square winnerKSq = pos.king_square(strongSide); - Square loserKSq = pos.king_square(weakSide); - Square knightSq = pos.list(weakSide)[0]; - - Value result = VALUE_KNOWN_WIN - + PushToCorners[loserKSq] - + PushClose[square_distance(winnerKSq, loserKSq)] - + PushAway[square_distance(loserKSq, knightSq)]; - - return strongSide == pos.side_to_move() ? result : -result; -} - - /// Some cases of trivial draws template<> Value Endgame::operator()(const Position&) const { return VALUE_DRAW; } -template<> Value Endgame::operator()(const Position&) const { return VALUE_DRAW; } /// KB and one or more pawns vs K. It checks for draws with rook pawns and @@ -397,7 +371,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const { && !(pawns & ~file_bb(pawnFile))) { Square bishopSq = pos.list(strongSide)[0]; - Square queeningSq = relative_square(strongSide, pawnFile | RANK_8); + Square queeningSq = relative_square(strongSide, make_square(pawnFile, RANK_8)); Square kingSq = pos.king_square(weakSide); if ( opposite_colors(queeningSq, bishopSq) @@ -489,7 +463,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const { File f = file_of(wpsq); Rank r = rank_of(wpsq); - Square queeningSq = f | RANK_8; + Square queeningSq = make_square(f, RANK_8); int tempo = (pos.side_to_move() == strongSide); // If the pawn is not too far advanced and the defending king defends the @@ -747,12 +721,12 @@ ScaleFactor Endgame::operator()(const Position& pos) const { if (relative_rank(strongSide, psq1) > relative_rank(strongSide, psq2)) { blockSq1 = psq1 + pawn_push(strongSide); - blockSq2 = file_of(psq2) | rank_of(psq1); + blockSq2 = make_square(file_of(psq2), rank_of(psq1)); } else { blockSq1 = psq2 + pawn_push(strongSide); - blockSq2 = file_of(psq1) | rank_of(psq2); + blockSq2 = make_square(file_of(psq1), rank_of(psq2)); } switch (file_distance(psq1, psq2)) @@ -817,7 +791,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const { /// KNP vs K. There is a single rule: if the pawn is a rook pawn on the 7th rank -/// and the defending king prevents the pawn from advancing the position is drawn. +/// and the defending king prevents the pawn from advancing, the position is drawn. template<> ScaleFactor Endgame::operator()(const Position& pos) const {