From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Sun, 28 Jul 2019 12:05:07 +0000 (+0200)
Subject: Simplify CTF bonus
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=a916cf3645aae5bfd9ffdaf15e89db6180e2c42d;p=fairystockfish.git

Simplify CTF bonus

racingkings STC
LLR: 2.99 (-2.94,2.94) [-10.00,5.00]
Total: 244 W: 124 L: 69 D: 51
http://35.161.250.236:6543/tests/view/5d3d8fa46e23db34f4206d12

racingkings LTC
LLR: 2.95 (-2.94,2.94) [-10.00,5.00]
Total: 148 W: 77 L: 27 D: 44
http://35.161.250.236:6543/tests/view/5d3d95886e23db34f4206d15
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index cb78ca7..95174d7 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -890,7 +890,7 @@ namespace {
                 int dist =  distance(s1, s2)
                           + (isKingCTF ? popcount(pos.attackers_to(s2) & pos.pieces(Them)) : 0)
                           + !!(pos.pieces(Us) & s2);
-                score += make_score(2500, 2500) / (1 + scale * dist * (!isKingCTF || pos.checking_permitted() ? dist : 1));
+                score += make_score(2500, 2500) / (1 + scale * dist * dist);
             }
         }
     }