From 299afcd88653739b80691991f7e5072a0505f542 Mon Sep 17 00:00:00 2001 From: Joerg Oster Date: Thu, 3 Apr 2014 10:38:11 +0200 Subject: [PATCH 1/1] Queen vs. 3 pieces imbalance Passed both STC LLR: 7.32 (-2.94,2.94) [-1.50,4.50] Total: 98108 W: 18087 L: 17576 D: 62445 And LTC LLR: 2.95 (-2.94,2.94) [0.00,6.00] Total: 15082 W: 2417 L: 2248 D: 10417 bench: 7717336 --- src/material.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/material.cpp b/src/material.cpp index 0fe132d4..9e46d05d 100644 --- a/src/material.cpp +++ b/src/material.cpp @@ -115,6 +115,17 @@ namespace { value += pc * v; } + + // Queen vs. 3 minors slightly favours the minors + if (pieceCount[Us][QUEEN] == 1 && pieceCount[Them][QUEEN] == 0) + { + int n = pieceCount[Them][KNIGHT] - pieceCount[Us][KNIGHT]; + int b = pieceCount[Them][BISHOP] - pieceCount[Us][BISHOP]; + + if ((n == 2 && b == 1) || (n == 1 && b == 2)) + value -= 66 * 16; + } + return value; } -- 2.39.2