Threefold repetition detection

[stockfish] / src / position.h

diff --git a/src/position.h b/src/position.h
index c322ab99ac238105b4c483176db528c53ed25915..1ee247e944d4b9bdfb0882137e5deb4c93b1959b 100644 (file)
--- a/src/position.h
+++ b/src/position.h
@@ -22,25 +22,13 @@
 #define POSITION_H_INCLUDED
 
 #include <cassert>
-#include <cstddef>  // For offsetof()
 #include <deque>
-#include <memory>   // For std::unique_ptr
+#include <memory> // For std::unique_ptr
 #include <string>
-#include <vector>
 
 #include "bitboard.h"
 #include "types.h"
 
-class Position;
-class Thread;
-
-namespace PSQT {
-
-  extern Score psq[PIECE_NB][SQUARE_NB];
-
-  void init();
-}
-
 
 /// StateInfo struct stores information needed to restore a Position object to
 /// its previous state when we retract a move. Whenever a move is made on the
@@ -58,7 +46,7 @@ struct StateInfo {
   Score  psq;
   Square epSquare;
 
-  // Not copied when making a move
+  // Not copied when making a move (will be recomputed anyhow)
   Key        key;
   Bitboard   checkersBB;
   Piece      capturedPiece;
@@ -76,9 +64,9 @@ typedef std::unique_ptr<std::deque<StateInfo>> StateListPtr;
 /// pieces, side to move, hash keys, castling info, etc. Important methods are
 /// do_move() and undo_move(), used by the search to update node info when
 /// traversing the search tree.
+class Thread;
 
 class Position {
-
 public:
   static void init();
 
@@ -88,6 +76,7 @@ public:
 
   // FEN string input/output
   Position& set(const std::string& fenStr, bool isChess960, StateInfo* si, Thread* th);
+  Position& set(const std::string& code, Color c, StateInfo* si);
   const std::string fen() const;
 
   // Position representation
@@ -139,14 +128,14 @@ public:
   bool opposite_bishops() const;
 
   // Doing and undoing moves
-  void do_move(Move m, StateInfo& st, bool givesCheck);
+  void do_move(Move m, StateInfo& newSt);
+  void do_move(Move m, StateInfo& newSt, bool givesCheck);
   void undo_move(Move m);
-  void do_null_move(StateInfo& st);
+  void do_null_move(StateInfo& newSt);
   void undo_null_move();
 
-  // Static exchange evaluation
-  Value see(Move m) const;
-  Value see_sign(Move m) const;
+  // Static Exchange Evaluation
+  bool see_ge(Move m, Value value) const;
 
   // Accessing hash keys
   Key key() const;
@@ -161,8 +150,7 @@ public:
   bool is_chess960() const;
   Thread* this_thread() const;
   uint64_t nodes_searched() const;
-  void set_nodes_searched(uint64_t n);
-  bool is_draw() const;
+  bool is_draw(int ply) const;
   int rule50_count() const;
   Score psq_score() const;
   Value non_pawn_material(Color c) const;
@@ -354,10 +342,6 @@ inline uint64_t Position::nodes_searched() const {
   return nodes;
 }
 
-inline void Position::set_nodes_searched(uint64_t n) {
-  nodes = n;
-}
-
 inline bool Position::opposite_bishops() const {
   return   pieceCount[W_BISHOP] == 1
         && pieceCount[B_BISHOP] == 1
@@ -369,15 +353,13 @@ inline bool Position::is_chess960() const {
 }
 
 inline bool Position::capture_or_promotion(Move m) const {
-
   assert(is_ok(m));
   return type_of(m) != NORMAL ? type_of(m) != CASTLING : !empty(to_sq(m));
 }
 
 inline bool Position::capture(Move m) const {
-
-  // Castling is encoded as "king captures the rook"
   assert(is_ok(m));
+  // Castling is encoded as "king captures rook"
   return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == ENPASSANT;
 }
 
@@ -405,7 +387,7 @@ inline void Position::remove_piece(Piece pc, Square s) {
   // WARNING: This is not a reversible operation. If we remove a piece in
   // do_move() and then replace it in undo_move() we will put it at the end of
   // the list and not in its original place, it means index[] and pieceList[]
-  // are not guaranteed to be invariant to a do_move() + undo_move() sequence.
+  // are not invariant to a do_move() + undo_move() sequence.
   byTypeBB[ALL_PIECES] ^= s;
   byTypeBB[type_of(pc)] ^= s;
   byColorBB[color_of(pc)] ^= s;
@@ -431,4 +413,8 @@ inline void Position::move_piece(Piece pc, Square from, Square to) {
   pieceList[pc][index[to]] = to;
 }
 
+inline void Position::do_move(Move m, StateInfo& newSt) {
+  do_move(m, newSt, gives_check(m));
+}
+
 #endif // #ifndef POSITION_H_INCLUDED