From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Sat, 30 May 2020 15:27:16 +0000 (+0200)
Subject: Invert losing chess threat bonus
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=c4efab8ddc68a5eccc497084dd80bde6fb995cdb;p=fairystockfish.git

Invert losing chess threat bonus

giveaway STC
LLR: 2.96 (-2.94,2.94) [0.00,10.00]
Total: 162 W: 111 L: 25 D: 26
http://www.variantfishtest.org:6543/tests/view/5ed184f66e23db36d55f2c7b

giveaway LTC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 185 W: 121 L: 34 D: 30
http://www.variantfishtest.org:6543/tests/view/5ed20bc76e23db36d55f2c88

losers STC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 297 W: 183 L: 86 D: 28
http://www.variantfishtest.org:6543/tests/view/5ed1850e6e23db36d55f2c7e

losers LTC
LLR: 2.97 (-2.94,2.94) [0.00,10.00]
Total: 644 W: 338 L: 236 D: 70
http://www.variantfishtest.org:6543/tests/view/5ed20bd16e23db36d55f2c8a
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index d26fb11..9763547 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -622,7 +622,8 @@ namespace {
     if (pos.must_capture())
     {
         // Penalties for possible captures
-        score -= make_score(100, 100) * popcount(attackedBy[Us][ALL_PIECES] & pos.pieces(Them));
+        if (attackedBy[Us][ALL_PIECES] & pos.pieces(Them))
+            score -= make_score(1000, 1000) / popcount(attackedBy[Us][ALL_PIECES] & pos.pieces(Them));
 
         // Bonus if we threaten to force captures
         Bitboard moves = 0, piecebb = pos.pieces(Us);