From c8e5384c3a4a5d9ac709c9b50954907a7f07109c Mon Sep 17 00:00:00 2001 From: GuardianRM Date: Sat, 8 Jul 2017 14:07:25 -0700 Subject: [PATCH] Queen vs. Minors imbalance Addition of correction values in case of Imbalance of queens, depending on the number of light pieces on the side without a queen. Passed patch: STC: LLR: 2.95 (-2.94,2.94) [0.00,5.00] Total: 29036 W: 5379 L: 5130 D: 18527 LTC: LLR: 2.96 (-2.94,2.94) [0.00,5.00] Total: 13680 W: 1836 L: 1674 D: 10170 Bench: 6258930 Closes #1155 --- src/material.cpp | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/material.cpp b/src/material.cpp index dc2a3a3b..114f0831 100644 --- a/src/material.cpp +++ b/src/material.cpp @@ -58,6 +58,12 @@ namespace { 24, -32, 107, -51, 117, -9, -126, -21, 31 }; + // QueenMinorsImbalance[opp_minor_count] is applied when only one side has a queen. + // It contains a bonus/malus for the side with the queen. + const int QueenMinorsImbalance[16] = { + 31, -8, -15, -25, -5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 + }; + // Endgame evaluation and scaling functions are accessed directly and not through // the function maps because they correspond to more than one material hash key. Endgame EvaluateKXK[] = { Endgame(WHITE), Endgame(BLACK) }; @@ -111,6 +117,10 @@ namespace { bonus += pieceCount[Us][pt1] * v; } + // Special handling of Queen vs. Minors + if (pieceCount[Us][QUEEN] == 1 && pieceCount[Them][QUEEN] == 0) + bonus += QueenMinorsImbalance[pieceCount[Them][KNIGHT] + pieceCount[Them][BISHOP]]; + return bonus; } -- 2.39.2