X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=ec54d4e69ea5114265e0d47d05a4fd0cc68f2c4b;hp=19c5b0b8c6c45c97d89d5538095ed447680c8c15;hb=9b2635634714558cc492d1c31db7c93127369c88;hpb=e9296d694c72c2378b71ad29cfff2f2c7b45bb0c diff --git a/src/endgame.cpp b/src/endgame.cpp index 19c5b0b8..ec54d4e6 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -22,7 +22,7 @@ #include "bitcount.h" #include "endgame.h" -#include "pawns.h" +#include "movegen.h" using std::string; @@ -133,6 +133,13 @@ Value Endgame::operator()(const Position& pos) const { assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO); assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO); + // Stalemate detection with lone king + if ( pos.side_to_move() == weakerSide + && !pos.in_check() + && !MoveList(pos).size()) { + return VALUE_DRAW; + } + Square winnerKSq = pos.king_square(strongerSide); Square loserKSq = pos.king_square(weakerSide); @@ -143,9 +150,9 @@ Value Endgame::operator()(const Position& pos) const { if ( pos.piece_count(strongerSide, QUEEN) || pos.piece_count(strongerSide, ROOK) - || pos.piece_count(strongerSide, BISHOP) > 1) - // TODO: check for two equal-colored bishops! - result += VALUE_KNOWN_WIN; + || pos.both_color_bishops(strongerSide)) { + result += VALUE_KNOWN_WIN; + } return strongerSide == pos.side_to_move() ? result : -result; } @@ -205,10 +212,10 @@ Value Endgame::operator()(const Position& pos) const { } else { - wksq = flip(pos.king_square(BLACK)); - bksq = flip(pos.king_square(WHITE)); - wpsq = flip(pos.piece_list(BLACK, PAWN)[0]); - stm = flip(pos.side_to_move()); + wksq = ~pos.king_square(BLACK); + bksq = ~pos.king_square(WHITE); + wpsq = ~pos.piece_list(BLACK, PAWN)[0]; + stm = ~pos.side_to_move(); } if (file_of(wpsq) >= FILE_E) @@ -251,10 +258,10 @@ Value Endgame::operator()(const Position& pos) const { if (strongerSide == BLACK) { - wksq = flip(wksq); - wrsq = flip(wrsq); - bksq = flip(bksq); - bpsq = flip(bpsq); + wksq = ~wksq; + wrsq = ~wrsq; + bksq = ~bksq; + bpsq = ~bpsq; } Square queeningSq = make_square(file_of(bpsq), RANK_1); @@ -416,7 +423,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const { && abs(file_of(kingSq) - pawnFile) <= 1) { // The bishop has the wrong color, and the defending king is on the - // file of the pawn(s) or the neighboring file. Find the rank of the + // file of the pawn(s) or the adjacent file. Find the rank of the // frontmost pawn. Rank rank; if (strongerSide == WHITE) @@ -491,11 +498,11 @@ ScaleFactor Endgame::operator()(const Position& pos) const { // pawn is on the left half of the board. if (strongerSide == BLACK) { - wksq = flip(wksq); - wrsq = flip(wrsq); - wpsq = flip(wpsq); - bksq = flip(bksq); - brsq = flip(brsq); + wksq = ~wksq; + wrsq = ~wrsq; + wpsq = ~wpsq; + bksq = ~bksq; + brsq = ~brsq; } if (file_of(wpsq) > FILE_D) { @@ -768,7 +775,7 @@ ScaleFactor Endgame::operator()(const Position& pos) const { return SCALE_FACTOR_NONE; case 1: - // Pawns on neighboring files. Draw if defender firmly controls the square + // Pawns on adjacent files. Draw if defender firmly controls the square // in front of the frontmost pawn's path, and the square diagonally behind // this square on the file of the other pawn. if ( ksq == blockSq1 @@ -867,10 +874,10 @@ ScaleFactor Endgame::operator()(const Position& pos) const { if (strongerSide == BLACK) { - wksq = flip(wksq); - bksq = flip(bksq); - wpsq = flip(wpsq); - stm = flip(stm); + wksq = ~wksq; + bksq = ~bksq; + wpsq = ~wpsq; + stm = ~stm; } if (file_of(wpsq) >= FILE_E)