From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Sun, 6 Sep 2020 09:02:38 +0000 (+0200)
Subject: Always evaluate space bonus for slow variants
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=b15e9b60453b0a98deca808b76204c9e3a67595e;p=fairystockfish.git

Always evaluate space bonus for slow variants

makruk STC
LLR: 2.96 (-2.94,2.94) [0.00,10.00]
Total: 908 W: 111 L: 51 D: 746
http://www.variantfishtest.org:6543/tests/view/5f5203ed6e23db221d9e90a2

makruk LTC
LLR: 2.97 (-2.94,2.94) [0.00,10.00]
Total: 839 W: 82 L: 25 D: 732
http://www.variantfishtest.org:6543/tests/view/5f5387446e23db221d9e90e6

shatranj STC
LLR: 2.95 (-2.94,2.94) [0.00,10.00]
Total: 1180 W: 143 L: 81 D: 956
http://www.variantfishtest.org:6543/tests/view/5f5204066e23db221d9e90a5

shatranj LTC
LLR: 2.97 (-2.94,2.94) [0.00,10.00]
Total: 1026 W: 113 L: 53 D: 860
http://www.variantfishtest.org:6543/tests/view/5f53ab6a6e23db221d9e90ea

losalamos STC
LLR: 3.00 (-2.94,2.94) [-10.00,5.00]
Total: 1171 W: 312 L: 272 D: 587
http://www.variantfishtest.org:6543/tests/view/5f5295db6e23db221d9e90bd
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index ec4af34..5056b79 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -893,7 +893,7 @@ namespace {
 
     bool pawnsOnly = !(pos.pieces(Us) ^ pos.pieces(Us, PAWN));
 
-    if (pos.non_pawn_material() < SpaceThreshold && !pos.captures_to_hand() && !pawnsOnly)
+    if (pos.non_pawn_material() < SpaceThreshold && !pos.captures_to_hand() && !pawnsOnly && pos.double_step_enabled())
         return SCORE_ZERO;
 
     constexpr Color Them     = ~Us;