X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=311443ec939f82ac7b2af69c836524ba8e8768a4;hp=869a36d76ceb5d0358765e7dd89ef639f240f6f6;hb=15e21911110f9d459c4fef2bb17903d97345d0b9;hpb=a646f74e6a62af756b2e51756a81ee983db4ff34 diff --git a/src/endgame.cpp b/src/endgame.cpp index 869a36d7..311443ec 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -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"); @@ -168,6 +166,7 @@ Value Endgame::operator()(const Position& pos) const { if ( pos.count(strongSide) || pos.count(strongSide) + ||(pos.count(strongSide) && pos.count(strongSide)) || pos.bishop_pair(strongSide)) result += VALUE_KNOWN_WIN; @@ -242,18 +241,18 @@ 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 if (wksq < psq && file_of(wksq) == file_of(psq)) - result = RookValueEg - Value(square_distance(wksq, psq)); + result = RookValueEg - square_distance(wksq, psq); // If the weaker side's king is too far from the pawn and the rook, // it's a win. else if ( square_distance(bksq, psq) >= 3 + (pos.side_to_move() == weakSide) && square_distance(bksq, rsq) >= 3) - result = RookValueEg - Value(square_distance(wksq, psq)); + result = RookValueEg - square_distance(wksq, psq); // If the pawn is far advanced and supported by the defending king, // the position is drawish @@ -261,13 +260,12 @@ Value Endgame::operator()(const Position& pos) const { && square_distance(bksq, psq) == 1 && rank_of(wksq) >= RANK_4 && square_distance(wksq, psq) > 2 + (pos.side_to_move() == strongSide)) - result = Value(80 - square_distance(wksq, psq) * 8); + result = Value(80) - 8 * square_distance(wksq, psq); else - result = Value(200) - - Value(square_distance(wksq, psq + DELTA_S) * 8) - + Value(square_distance(bksq, psq + DELTA_S) * 8) - + Value(square_distance(psq, queeningSq) * 8); + result = Value(200) - 8 * ( square_distance(wksq, psq + DELTA_S) + - square_distance(bksq, psq + DELTA_S) + - square_distance(psq, queeningSq)); return strongSide == pos.side_to_move() ? result : -result; } @@ -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))