/// move_to_uci() converts a move to a string in coordinate notation
/// (g1f3, a7a8q, etc.). The only special case is castling moves, where we
/// print in the e1g1 notation in normal chess mode, and in e1h1 notation in
-/// Chess960 mode.
+/// Chess960 mode. Instead internally Move is coded as "king captures rook".
const string move_to_uci(Move m, bool chess960) {
if (m == MOVE_NULL)
return "0000";
- if (move_is_short_castle(m) && !chess960)
- return from == SQ_E1 ? "e1g1" : "e8g8";
-
- if (move_is_long_castle(m) && !chess960)
- return from == SQ_E1 ? "e1c1" : "e8c8";
+ if (move_is_castle(m) && !chess960)
+ to = from + (square_file(to) == FILE_H ? Square(2) : -Square(2));
if (move_is_promotion(m))
- promotion = char(tolower(piece_type_to_char(move_promotion_piece(m))));
+ promotion = char(tolower(piece_type_to_char(promotion_piece_type(m))));
return square_to_string(from) + square_to_string(to) + promotion;
}
Move move_from_uci(const Position& pos, const string& str) {
- MoveStack mlist[MAX_MOVES];
- MoveStack* last = generate<MV_LEGAL>(pos, mlist);
-
- for (MoveStack* cur = mlist; cur != last; cur++)
- if (str == move_to_uci(cur->move, pos.is_chess960()))
- return cur->move;
+ for (MoveList<MV_LEGAL> ml(pos); !ml.end(); ++ml)
+ if (str == move_to_uci(ml.move(), pos.is_chess960()))
+ return ml.move();
return MOVE_NONE;
}
/// move_to_san() takes a position and a move as input, where it is assumed
-/// that the move is a legal move from the position. The return value is
+/// that the move is a legal move for the position. The return value is
/// a string containing the move in short algebraic notation.
const string move_to_san(Position& pos, Move m) {
- assert(pos.is_ok());
- assert(move_is_ok(m));
-
- MoveStack mlist[MAX_MOVES];
- Square from = move_from(m);
- Square to = move_to(m);
- PieceType pt = pos.type_of_piece_on(from);
- string san;
-
if (m == MOVE_NONE)
return "(none)";
if (m == MOVE_NULL)
return "(null)";
- if (move_is_long_castle(m))
- san = "O-O-O";
- else if (move_is_short_castle(m))
- san = "O-O";
+ assert(pos.is_ok());
+ assert(move_is_ok(m));
+
+ Bitboard attackers;
+ bool ambiguousMove, ambiguousFile, ambiguousRank;
+ Square sq, from = move_from(m);
+ Square to = move_to(m);
+ PieceType pt = piece_type(pos.piece_on(from));
+ string san;
+
+ if (move_is_castle(m))
+ san = (move_to(m) < move_from(m) ? "O-O-O" : "O-O");
else
{
if (pt != PAWN)
{
san = piece_type_to_char(pt);
- // Collect all legal moves of piece type 'pt' with destination 'to'
- MoveStack* last = generate<MV_LEGAL>(pos, mlist);
- int f = 0, r = 0;
-
- for (MoveStack* cur = mlist; cur != last; cur++)
- if ( move_to(cur->move) == to
- && pos.type_of_piece_on(move_from(cur->move)) == pt)
- {
- if (square_file(move_from(cur->move)) == square_file(from))
- f++;
-
- if (square_rank(move_from(cur->move)) == square_rank(from))
- r++;
- }
-
- assert(f > 0 && r > 0);
-
// Disambiguation if we have more then one piece with destination 'to'
- if (f == 1 && r > 1)
- san += file_to_char(square_file(from));
- else if (f > 1 && r == 1)
- san += rank_to_char(square_rank(from));
- else if (f > 1 && r > 1)
- san += square_to_string(from);
+ // note that for pawns is not needed because starting file is explicit.
+ attackers = pos.attackers_to(to) & pos.pieces(pt, pos.side_to_move());
+ clear_bit(&attackers, from);
+ ambiguousMove = ambiguousFile = ambiguousRank = false;
+
+ while (attackers)
+ {
+ sq = pop_1st_bit(&attackers);
+
+ if (square_file(sq) == square_file(from))
+ ambiguousFile = true;
+
+ if (square_rank(sq) == square_rank(from))
+ ambiguousRank = true;
+
+ ambiguousMove = true;
+ }
+
+ if (ambiguousMove)
+ {
+ if (!ambiguousFile)
+ san += file_to_char(square_file(from));
+ else if (!ambiguousRank)
+ san += rank_to_char(square_rank(from));
+ else
+ san += square_to_string(from);
+ }
}
if (pos.move_is_capture(m))
if (move_is_promotion(m))
{
san += '=';
- san += piece_type_to_char(move_promotion_piece(m));
+ san += piece_type_to_char(promotion_piece_type(m));
}
}