From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Fri, 19 Apr 2019 17:28:46 +0000 (+0200)
Subject: Tweak threat evaluation for losing chess variants
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=d7c6d8055310d4ff80e0d083ae006f62271d4621;p=fairystockfish.git

Tweak threat evaluation for losing chess variants

giveaway STC
LLR: 2.97 (-2.94,2.94) [0.00,10.00]
Total: 5279 W: 2193 L: 2034 D: 1052
http://35.161.250.236:6543/tests/view/5cb197406e23db76ed2526e8

giveaway LTC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 23616 W: 9228 L: 8824 D: 5564
http://35.161.250.236:6543/tests/view/5cb2c5fe6e23db76ed252702

losers STC (failed)
LLR: -2.97 (-2.94,2.94) [-10.00,5.00]
Total: 7179 W: 3195 L: 3309 D: 675
http://35.161.250.236:6543/tests/view/5cb197556e23db76ed2526eb

losers LTC
LLR: 2.98 (-2.94,2.94) [-10.00,5.00]
Total: 2363 W: 1066 L: 1021 D: 276
http://35.161.250.236:6543/tests/view/5cb2c60b6e23db76ed252704
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 2c6339b..0407bfd 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -610,7 +610,7 @@ namespace {
                 moves |= pos.moves_from(Us, type_of(pos.piece_on(s)), s);
         }
         score += make_score(200, 200) * popcount(attackedBy[Them][ALL_PIECES] & moves & ~pos.pieces());
-        score += make_score(200, 200) * popcount(attackedBy[Them][ALL_PIECES] & moves & ~pos.pieces() & ~attackedBy2[Us]);
+        score += make_score(200, 220) * popcount(attackedBy[Them][ALL_PIECES] & moves & ~pos.pieces() & ~attackedBy2[Us]);
     }
 
     // Non-pawn enemies