From c5b2a92cd17c65a639ec6739dd511767f65e188d Mon Sep 17 00:00:00 2001 From: protonspring Date: Tue, 30 Jun 2020 10:17:50 -0600 Subject: [PATCH] denormalize KRKP. a non-functional code style change that denormalizes the KRKP endgame, making it somewhat easier to read. closes https://github.com/official-stockfish/Stockfish/pull/2786 No functional change --- src/endgame.cpp | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/src/endgame.cpp b/src/endgame.cpp index be0755a8..40f49dce 100644 --- a/src/endgame.cpp +++ b/src/endgame.cpp @@ -181,15 +181,15 @@ Value Endgame::operator()(const Position& pos) const { assert(verify_material(pos, strongSide, RookValueMg, 0)); assert(verify_material(pos, weakSide, VALUE_ZERO, 1)); - Square strongKing = relative_square(strongSide, pos.square(strongSide)); - Square weakKing = relative_square(strongSide, pos.square(weakSide)); - Square strongRook = relative_square(strongSide, pos.square(strongSide)); - Square weakPawn = relative_square(strongSide, pos.square(weakSide)); - Square queeningSquare = make_square(file_of(weakPawn), RANK_1); + Square strongKing = pos.square(strongSide); + Square weakKing = pos.square(weakSide); + Square strongRook = pos.square(strongSide); + Square weakPawn = pos.square(weakSide); + Square queeningSquare = make_square(file_of(weakPawn), relative_rank(weakSide, RANK_8)); Value result; // If the stronger side's king is in front of the pawn, it's a win - if (forward_file_bb(WHITE, strongKing) & weakPawn) + if (forward_file_bb(strongSide, strongKing) & weakPawn) result = RookValueEg - distance(strongKing, weakPawn); // If the weaker side's king is too far from the pawn and the rook, @@ -200,15 +200,15 @@ Value Endgame::operator()(const Position& pos) const { // If the pawn is far advanced and supported by the defending king, // the position is drawish - else if ( rank_of(weakKing) <= RANK_3 + else if ( relative_rank(strongSide, weakKing) <= RANK_3 && distance(weakKing, weakPawn) == 1 - && rank_of(strongKing) >= RANK_4 + && relative_rank(strongSide, strongKing) >= RANK_4 && distance(strongKing, weakPawn) > 2 + (pos.side_to_move() == strongSide)) result = Value(80) - 8 * distance(strongKing, weakPawn); else - result = Value(200) - 8 * ( distance(strongKing, weakPawn + SOUTH) - - distance(weakKing, weakPawn + SOUTH) + result = Value(200) - 8 * ( distance(strongKing, weakPawn + pawn_push(weakSide)) + - distance(weakKing, weakPawn + pawn_push(weakSide)) - distance(weakPawn, queeningSquare)); return strongSide == pos.side_to_move() ? result : -result; -- 2.39.2