Detect stalemate in KXK endgames

[stockfish] / src / position.h

diff --git a/src/position.h b/src/position.h
index bcbfc850d0c8b15eb4677f63b447996fde6fdeca..8229e71b4a1a4e8c3c66f7cdcd12cbaa580635b2 100644 (file)
--- a/src/position.h
+++ b/src/position.h
@@ -189,6 +189,7 @@ public:
   template<bool SkipRepetition> bool is_draw() const;
   int startpos_ply_counter() const;
   bool opposite_colored_bishops() const;
+  bool both_color_bishops(Color c) const;
   bool has_pawn_on_7th(Color c) const;
   bool is_chess960() const;
 
@@ -432,6 +433,12 @@ inline bool Position::opposite_colored_bishops() const {
         && opposite_colors(pieceList[WHITE][BISHOP][0], pieceList[BLACK][BISHOP][0]);
 }
 
+inline bool Position::both_color_bishops(Color c) const {
+  // Assumes that there are only two bishops
+  return  pieceCount[c][BISHOP] >= 2 &&
+          opposite_colors(pieceList[c][BISHOP][0], pieceList[c][BISHOP][1]);
+}
+
 inline bool Position::has_pawn_on_7th(Color c) const {
   return pieces(PAWN, c) & rank_bb(relative_rank(c, RANK_7));
 }