From 13d06edb8498bb32b0fd7bda82a87eb4874385af Mon Sep 17 00:00:00 2001 From: protonspring Date: Fri, 14 Sep 2018 09:04:11 -0600 Subject: [PATCH] Two simplifications in passed pawns evaluation These two simplifications appear to be affecting and/or offsetting each other. Neither can be removed independently, but in combination they pass -3,1. STC LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 36391 W: 7888 L: 7795 D: 20708 http://tests.stockfishchess.org/tests/view/5b9bce410ebc592cf275f1b2 LTC LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 19513 W: 3237 L: 3114 D: 13162 http://tests.stockfishchess.org/tests/view/5b9c0edf0ebc592cf275f80e Closes https://github.com/official-stockfish/Stockfish/pull/1769 bench 4059356 --- src/evaluate.cpp | 6 ------ 1 file changed, 6 deletions(-) diff --git a/src/evaluate.cpp b/src/evaluate.cpp index c2e7efef..261bb479 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -159,7 +159,6 @@ namespace { constexpr Score CloseEnemies = S( 6, 0); constexpr Score CorneredBishop = S( 50, 50); constexpr Score Hanging = S( 57, 32); - constexpr Score HinderPassedPawn = S( 8, 0); constexpr Score KingProtector = S( 6, 6); constexpr Score KnightOnQueen = S( 21, 11); constexpr Score LongDiagonalBishop = S( 46, 0); @@ -638,9 +637,6 @@ namespace { assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up))); - if (forward_file_bb(Us, s) & pos.pieces(Them)) - score -= HinderPassedPawn; - int r = relative_rank(Us, s); int w = PassedDanger[r]; @@ -688,8 +684,6 @@ namespace { bonus += make_score(k * w, k * w); } - else if (pos.pieces(Us) & blockSq) - bonus += make_score(w + r * 2, w + r * 2); } // w != 0 // Scale down bonus for candidate passers which need more than one -- 2.39.2