}
-/// Position::pretty() returns an ASCII representation of the position to be
-/// printed to the standard output together with the move's san notation.
+/// Position::pretty() returns an ASCII representation of the position
-const string Position::pretty(Move m) const {
+const string Position::pretty() const {
std::ostringstream ss;
- if (m)
- ss << "\nMove: " << (sideToMove == BLACK ? ".." : "")
- << move_to_san(*const_cast<Position*>(this), m);
-
ss << "\n +---+---+---+---+---+---+---+---+\n";
for (Rank r = RANK_8; r >= RANK_1; --r)
for (Bitboard b = checkers(); b; )
ss << to_string(pop_lsb(&b)) << " ";
- ss << "\nLegal moves: ";
- for (MoveList<LEGAL> it(*this); *it; ++it)
- ss << move_to_san(*const_cast<Position*>(this), *it) << " ";
-
return ss.str();
}
+/// Position::game_phase() calculates the game phase interpolating total non-pawn
+/// material between endgame and midgame limits.
+
+Phase Position::game_phase() const {
+
+ Value npm = st->npMaterial[WHITE] + st->npMaterial[BLACK];
+
+ npm = std::max(EndgameLimit, std::min(npm, MidgameLimit));
+
+ return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
+}
+
+
/// Position::check_blockers() returns a bitboard of all the pieces with color
/// 'c' that are blocking check on the king with color 'kingColor'. A piece
/// blocks a check if removing that piece from the board would result in a
sideToMove = ~sideToMove;
}
+// Position::hash_after_move() updates the hash key needed for the speculative prefetch.
+// It doesn't recognize special moves like castling, en-passant and promotions.
+Key Position::hash_after_move(Move m) const {
+
+ int from = from_sq(m);
+ int to = to_sq(m);
+ Piece p = board[from];
+ Piece capP = board[to];
+ Key ret = st->key ^ Zobrist::side;
+ if (capP != NO_PIECE)
+ ret ^= Zobrist::psq[color_of(capP)][type_of(capP)][to];
+ ret ^= Zobrist::psq[color_of(p)][type_of(p)][to];
+ ret ^= Zobrist::psq[color_of(p)][type_of(p)][from];
+ return ret;
+}
/// Position::see() is a static exchange evaluator: It tries to estimate the
/// material gain or loss resulting from a move.
bool Position::is_draw() const {
- if ( !pieces(PAWN)
- && (non_pawn_material(WHITE) + non_pawn_material(BLACK) <= BishopValueMg))
- return true;
-
if (st->rule50 > 99 && (!checkers() || MoveList<LEGAL>(*this).size()))
return true;