From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Tue, 1 Oct 2019 20:07:06 +0000 (+0200)
Subject: Make drop region constraint more explicit
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=79826fd6058cd4854c58e68226deb61b1516bfeb;p=fairystockfish.git

Make drop region constraint more explicit

No functional change.
---

diff --git a/src/position.cpp b/src/position.cpp
index f6ef5db..ea2dfe6 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -793,7 +793,7 @@ bool Position::legal(Move m) const {
   {
       if (type_of(moved_piece(m)) != BISHOP)
       {
-          Bitboard remaining = drop_region(us) & ~pieces() & ~SquareBB[to] & board_bb();
+          Bitboard remaining = drop_region(us, BISHOP) & ~pieces() & ~square_bb(to);
           // Are enough squares available to drop bishops on opposite colors?
           if (  (!( DarkSquares & pieces(us, BISHOP)) && ( DarkSquares & remaining))
               + (!(~DarkSquares & pieces(us, BISHOP)) && (~DarkSquares & remaining)) < count_in_hand(us, BISHOP))