X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=348feecf70bf5e170211460a23145a55749610dd;hp=bb756f3b20cd558922c4fc6c416b055e962c3b6d;hb=324ca87affc4959f7017e83437fb06b6e770449c;hpb=469e7c5143af0785d6ba41cdef731ac1f403141c diff --git a/src/endgame.cpp b/src/endgame.cpp index bb756f3b..348feecf 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -155,7 +155,7 @@ Value EvaluationFunction::apply(const Position& pos) const { // kbnk_mate_table() tries to drive toward corners A1 or H8, // if we have a bishop that cannot reach the above squares we // mirror the kings so to drive enemy toward corners A8 or H1. - if (!same_color_squares(bishopSquare, SQ_A1)) + if (opposite_color_squares(bishopSquare, SQ_A1)) { winnerKSq = flop_square(winnerKSq); loserKSq = flop_square(loserKSq); @@ -401,7 +401,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square queeningSq = relative_square(strongerSide, make_square(pawnFile, RANK_8)); Square kingSq = pos.king_square(weakerSide); - if ( !same_color_squares(queeningSq, bishopSq) + if ( opposite_color_squares(queeningSq, bishopSq) && file_distance(square_file(kingSq), pawnFile) <= 1) { // The bishop has the wrong color, and the defending king is on the @@ -446,8 +446,8 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square kingSq = pos.king_square(weakerSide); if ( relative_rank(weakerSide, kingSq) <= RANK_2 && relative_rank(weakerSide, pos.king_square(strongerSide)) >= RANK_4 - && (pos.pieces(ROOK, weakerSide) & relative_rank_bb(weakerSide, RANK_3)) - && (pos.pieces(PAWN, weakerSide) & relative_rank_bb(weakerSide, RANK_2)) + && (pos.pieces(ROOK, weakerSide) & rank_bb(relative_rank(weakerSide, RANK_3))) + && (pos.pieces(PAWN, weakerSide) & rank_bb(relative_rank(weakerSide, RANK_2))) && (pos.attacks_from(kingSq) & pos.pieces(PAWN, weakerSide))) { Square rsq = pos.piece_list(weakerSide, ROOK, 0); @@ -678,12 +678,12 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // Case 1: Defending king blocks the pawn, and cannot be driven away if ( square_file(weakerKingSq) == square_file(pawnSq) && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq) - && ( !same_color_squares(weakerKingSq, strongerBishopSq) + && ( opposite_color_squares(weakerKingSq, strongerBishopSq) || relative_rank(strongerSide, weakerKingSq) <= RANK_6)) return SCALE_FACTOR_ZERO; // Case 2: Opposite colored bishops - if (!same_color_squares(strongerBishopSq, weakerBishopSq)) + if (opposite_color_squares(strongerBishopSq, weakerBishopSq)) { // We assume that the position is drawn in the following three situations: // @@ -699,11 +699,12 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { return SCALE_FACTOR_ZERO; else { - Bitboard ray = ray_bb(pawnSq, (strongerSide == WHITE)? SIGNED_DIR_N : SIGNED_DIR_S); - if (ray & pos.pieces(KING, weakerSide)) + Bitboard path = squares_in_front_of(strongerSide, pawnSq); + + if (path & pos.pieces(KING, weakerSide)) return SCALE_FACTOR_ZERO; - if ( (pos.attacks_from(weakerBishopSq) & ray) + if ( (pos.attacks_from(weakerBishopSq) & path) && square_distance(weakerBishopSq, pawnSq) >= 3) return SCALE_FACTOR_ZERO; } @@ -727,8 +728,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { Square wbsq = pos.piece_list(strongerSide, BISHOP, 0); Square bbsq = pos.piece_list(weakerSide, BISHOP, 0); - if (same_color_squares(wbsq, bbsq)) - // Not opposite-colored bishops, no scaling + if (!opposite_color_squares(wbsq, bbsq)) return SCALE_FACTOR_NONE; Square ksq = pos.king_square(weakerSide); @@ -756,7 +756,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // some square in the frontmost pawn's path. if ( square_file(ksq) == square_file(blockSq1) && relative_rank(strongerSide, ksq) >= relative_rank(strongerSide, blockSq1) - && !same_color_squares(ksq, wbsq)) + && opposite_color_squares(ksq, wbsq)) return SCALE_FACTOR_ZERO; else return SCALE_FACTOR_NONE; @@ -766,14 +766,14 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { // 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 - && !same_color_squares(ksq, wbsq) + && opposite_color_squares(ksq, wbsq) && ( bbsq == blockSq2 || (pos.attacks_from(blockSq2) & pos.pieces(BISHOP, weakerSide)) || rank_distance(r1, r2) >= 2)) return SCALE_FACTOR_ZERO; else if ( ksq == blockSq2 - && !same_color_squares(ksq, wbsq) + && opposite_color_squares(ksq, wbsq) && ( bbsq == blockSq1 || (pos.attacks_from(blockSq1) & pos.pieces(BISHOP, weakerSide)))) return SCALE_FACTOR_ZERO; @@ -807,7 +807,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const { if ( square_file(weakerKingSq) == square_file(pawnSq) && relative_rank(strongerSide, pawnSq) < relative_rank(strongerSide, weakerKingSq) - && ( !same_color_squares(weakerKingSq, strongerBishopSq) + && ( opposite_color_squares(weakerKingSq, strongerBishopSq) || relative_rank(strongerSide, weakerKingSq) <= RANK_6)) return SCALE_FACTOR_ZERO;