From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Sun, 10 Nov 2019 13:00:24 +0000 (+0100)
Subject: Calculate pins by cannons
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=bcc0f655f0cc5e56a25b8f225584a283ad434b65;p=fairystockfish.git

Calculate pins by cannons

xiangqi
LLR: 3.01 (-2.94,2.94) [0.00,10.00]
Total: 868 W: 303 L: 218 D: 347
---

diff --git a/src/position.cpp b/src/position.cpp
index 05f597f..1eed7d8 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -722,7 +722,7 @@ Bitboard Position::slider_blockers(Bitboard sliders, Square s, Bitboard& pinners
   {
       Bitboard b = sliders & (PseudoAttacks[~c][pt][s] ^ LeaperAttacks[~c][pt][s]) & pieces(c, pt);
       if (b)
-          snipers |= b & ~attacks_from(~c, pt, s);
+          snipers |= b & ~attacks_bb(~c, pt, s, pieces());
   }
   Bitboard occupancy = pieces() ^ snipers;
 
@@ -731,7 +731,7 @@ Bitboard Position::slider_blockers(Bitboard sliders, Square s, Bitboard& pinners
     Square sniperSq = pop_lsb(&snipers);
     Bitboard b = between_bb(s, sniperSq) & occupancy;
 
-    if (b && !more_than_one(b))
+    if (b && (!more_than_one(b) || (type_of(piece_on(sniperSq)) == CANNON && popcount(b) == 2)))
     {
         blockers |= b;
         if (b & pieces(color_of(piece_on(s))))