From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Tue, 18 Dec 2018 22:09:31 +0000 (+0100)
Subject: Unlimited mobility area for losing chess variants
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=e11d07b062afd0dd4d08e1c4bfc37579917bbc67;p=fairystockfish.git

Unlimited mobility area for losing chess variants

losers STC
LLR: 2.97 (-2.94,2.94) [0.00,10.00]
Total: 1778 W: 818 L: 703 D: 257
http://35.161.250.236:6543/tests/view/5c1971166e23db24728955cb

giveaway STC
LLR: -2.98 (-2.94,2.94) [0.00,10.00]
Total: 19458 W: 6544 L: 6373 D: 6541
http://35.161.250.236:6543/tests/view/5c1970fc6e23db24728955c8
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index fcd53cf..c0e7b0d 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -265,7 +265,10 @@ namespace {
 
     // Squares occupied by those pawns, by our king or queen, or controlled by enemy pawns
     // are excluded from the mobility area.
-    mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them) | shift<Down>(pos.pieces(Them, SHOGI_PAWN)));
+    if (pos.must_capture())
+        mobilityArea[Us] = AllSquares;
+    else
+        mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them) | shift<Down>(pos.pieces(Them, SHOGI_PAWN)));
 
     // Initialise attackedBy bitboards for kings and pawns
     attackedBy[Us][KING] = pos.count<KING>(Us) ? pos.attacks_from<KING>(Us, pos.square<KING>(Us)) : 0;