checkSq[KING] = EmptyBoardBB;
}
+
+/// Position c'tors. Here we always create a slower but safer copy of
+/// the original position or the FEN string, we want the new born Position
+/// object do not depend on any external data. Instead if we know what we
+/// are doing and we need speed we can create a position with default
+/// c'tor Position() and then use just fast_copy().
+
+Position::Position() {}
+
Position::Position(const Position& pos) {
- copy(pos);
+
+ fast_copy(pos);
+ detach(); // Always detach() in copy c'tor to avoid surprises
}
Position::Position(const string& fen) {
+
from_fen(fen);
}
+/// Position::fast_copy() creates a partial copy of the given position,
+/// only data that changes with a do_move() / undo_move() cycle is copied,
+/// in particular for stateInfo are copied only the pointers, so that the
+/// actual data remains stored in the parent Position. This is not a problem
+/// if the parent Position is known not to be destroyed while we are still alive,
+/// as is the common case, see detach() otherwise.
+
+void Position::fast_copy(const Position& pos) {
+
+ memcpy(this, &pos, sizeof(Position));
+}
+
+
+/// Position::detach() copies the content of the current state and castling
+/// masks inside the position itself. This is needed when the st pointee could
+/// become stale, as example because the caller is about to going out of scope.
+
+void Position::detach() {
+
+ startState = *st;
+ st = &startState;
+ st->previous = NULL; // as a safe guard
+}
+
+
/// Position::from_fen() initializes the position object with the given FEN
/// string. This function is not very robust - make sure that input FENs are
/// correct (this is assumed to be the responsibility of the GUI).
}
i++;
- while(strchr("KQkqabcdefghABCDEFGH-", fen[i])) {
- if (fen[i] == '-')
- {
- i++;
- break;
- }
- else if(fen[i] == 'K') allow_oo(WHITE);
- else if(fen[i] == 'Q') allow_ooo(WHITE);
- else if(fen[i] == 'k') allow_oo(BLACK);
- else if(fen[i] == 'q') allow_ooo(BLACK);
- else if(fen[i] >= 'A' && fen[i] <= 'H') {
- File rookFile, kingFile = FILE_NONE;
- for(Square square = SQ_B1; square <= SQ_G1; square++)
- if(piece_on(square) == WK)
- kingFile = square_file(square);
- if(kingFile == FILE_NONE) {
- std::cout << "Error in FEN at character " << i << std::endl;
- return;
- }
- initialKFile = kingFile;
- rookFile = File(fen[i] - 'A') + FILE_A;
- if(rookFile < initialKFile) {
- allow_ooo(WHITE);
- initialQRFile = rookFile;
- }
- else {
- allow_oo(WHITE);
- initialKRFile = rookFile;
+ while (strchr("KQkqabcdefghABCDEFGH-", fen[i])) {
+ if (fen[i] == '-')
+ {
+ i++;
+ break;
}
- }
- else if(fen[i] >= 'a' && fen[i] <= 'h') {
- File rookFile, kingFile = FILE_NONE;
- for(Square square = SQ_B8; square <= SQ_G8; square++)
- if(piece_on(square) == BK)
- kingFile = square_file(square);
- if(kingFile == FILE_NONE) {
- std::cout << "Error in FEN at character " << i << std::endl;
- return;
+ else if (fen[i] == 'K') allow_oo(WHITE);
+ else if (fen[i] == 'Q') allow_ooo(WHITE);
+ else if (fen[i] == 'k') allow_oo(BLACK);
+ else if (fen[i] == 'q') allow_ooo(BLACK);
+ else if (fen[i] >= 'A' && fen[i] <= 'H') {
+ File rookFile, kingFile = FILE_NONE;
+ for (Square square = SQ_B1; square <= SQ_G1; square++)
+ if (piece_on(square) == WK)
+ kingFile = square_file(square);
+ if (kingFile == FILE_NONE) {
+ std::cout << "Error in FEN at character " << i << std::endl;
+ return;
+ }
+ initialKFile = kingFile;
+ rookFile = File(fen[i] - 'A') + FILE_A;
+ if (rookFile < initialKFile) {
+ allow_ooo(WHITE);
+ initialQRFile = rookFile;
+ }
+ else {
+ allow_oo(WHITE);
+ initialKRFile = rookFile;
+ }
}
- initialKFile = kingFile;
- rookFile = File(fen[i] - 'a') + FILE_A;
- if(rookFile < initialKFile) {
- allow_ooo(BLACK);
- initialQRFile = rookFile;
+ else if (fen[i] >= 'a' && fen[i] <= 'h') {
+ File rookFile, kingFile = FILE_NONE;
+ for (Square square = SQ_B8; square <= SQ_G8; square++)
+ if (piece_on(square) == BK)
+ kingFile = square_file(square);
+ if (kingFile == FILE_NONE) {
+ std::cout << "Error in FEN at character " << i << std::endl;
+ return;
+ }
+ initialKFile = kingFile;
+ rookFile = File(fen[i] - 'a') + FILE_A;
+ if (rookFile < initialKFile) {
+ allow_ooo(BLACK);
+ initialQRFile = rookFile;
+ }
+ else {
+ allow_oo(BLACK);
+ initialKRFile = rookFile;
+ }
}
else {
- allow_oo(BLACK);
- initialKRFile = rookFile;
+ std::cout << "Error in FEN at character " << i << std::endl;
+ return;
}
- }
- else {
- std::cout << "Error in FEN at character " << i << std::endl;
- return;
- }
- i++;
+ i++;
}
// Skip blanks
while (fen[i] == ' ')
i++;
- // En passant square
+ // En passant square -- ignore if no capture is possible
if ( i <= fen.length() - 2
&& (fen[i] >= 'a' && fen[i] <= 'h')
&& (fen[i+1] == '3' || fen[i+1] == '6'))
- st->epSquare = square_from_string(fen.substr(i, 2));
+ {
+ Square fenEpSquare = square_from_string(fen.substr(i, 2));
+ Color them = opposite_color(sideToMove);
+ if (attacks_from<PAWN>(fenEpSquare, them) & this->pieces(PAWN, sideToMove))
+ st->epSquare = square_from_string(fen.substr(i, 2));
+ }
// Various initialisation
for (Square sq = SQ_A1; sq <= SQ_H8; sq++)
fen += (sideToMove == WHITE ? "w " : "b ");
if (st->castleRights != NO_CASTLES)
{
- if (can_castle_kingside(WHITE)) fen += 'K';
- if (can_castle_queenside(WHITE)) fen += 'Q';
- if (can_castle_kingside(BLACK)) fen += 'k';
- if (can_castle_queenside(BLACK)) fen += 'q';
+ if (initialKFile == FILE_E && initialQRFile == FILE_A && initialKRFile == FILE_H)
+ {
+ if (can_castle_kingside(WHITE)) fen += 'K';
+ if (can_castle_queenside(WHITE)) fen += 'Q';
+ if (can_castle_kingside(BLACK)) fen += 'k';
+ if (can_castle_queenside(BLACK)) fen += 'q';
+ }
+ else
+ {
+ if (can_castle_kingside(WHITE))
+ fen += char(toupper(file_to_char(initialKRFile)));
+ if (can_castle_queenside(WHITE))
+ fen += char(toupper(file_to_char(initialQRFile)));
+ if (can_castle_kingside(BLACK))
+ fen += file_to_char(initialKRFile);
+ if (can_castle_queenside(BLACK))
+ fen += file_to_char(initialQRFile);
+ }
} else
fen += '-';
std::cout << std::endl;
if (m != MOVE_NONE)
{
+ Position p(*this);
string col = (color_of_piece_on(move_from(m)) == BLACK ? ".." : "");
- std::cout << "Move is: " << col << move_to_san(*this, m) << std::endl;
+ std::cout << "Move is: " << col << move_to_san(p, m) << std::endl;
}
for (Rank rank = RANK_8; rank >= RANK_1; rank--)
{
}
-/// Position::copy() creates a copy of the input position.
-
-void Position::copy(const Position& pos) {
-
- memcpy(this, &pos, sizeof(Position));
- saveState(); // detach and copy state info
-}
-
-
/// Position:hidden_checkers<>() returns a bitboard of all pinned (against the
/// king) pieces for the given color and for the given pinner type. Or, when
/// template parameter FindPinned is false, the pieces of the given color
}
+///
+PieceType Position::captured_piece() const {
+ return st->capture;
+}
+
/// Position::see() is a static exchange evaluator: It tries to estimate the
/// material gain or loss resulting from a move. There are three versions of
/// this function: One which takes a destination square as input, one takes a
}
-/// Position::saveState() copies the content of the current state
-/// inside startState and makes st point to it. This is needed
-/// when the st pointee could become stale, as example because
-/// the caller is about to going out of scope.
-
-void Position::saveState() {
-
- startState = *st;
- st = &startState;
- st->previous = NULL; // as a safe guard
-}
-
-
/// Position::clear() erases the position object to a pristine state, with an
/// empty board, white to move, and no castling rights.
for (Color c = WHITE; c <= BLACK; c++)
{
b = pieces(PAWN, c);
- while(b)
+ while (b)
{
s = pop_1st_bit(&b);
result ^= zobrist[c][PAWN][s];
for (PieceType pt = PAWN; pt <= KING; pt++)
{
b = pieces(pt, c);
- while(b)
+ while (b)
{
s = pop_1st_bit(&b);
assert(piece_on(s) == piece_of_color_and_type(c, pt));
static const bool debugNonPawnMaterial = false;
static const bool debugPieceCounts = false;
static const bool debugPieceList = false;
+ static const bool debugCastleSquares = false;
if (failedStep) *failedStep = 1;
if (failedStep) (*failedStep)++;
if (debugPieceList)
{
- for(Color c = WHITE; c <= BLACK; c++)
- for(PieceType pt = PAWN; pt <= KING; pt++)
- for(int i = 0; i < pieceCount[c][pt]; i++)
+ for (Color c = WHITE; c <= BLACK; c++)
+ for (PieceType pt = PAWN; pt <= KING; pt++)
+ for (int i = 0; i < pieceCount[c][pt]; i++)
{
if (piece_on(piece_list(c, pt, i)) != piece_of_color_and_type(c, pt))
return false;
return false;
}
}
+
+ if (failedStep) (*failedStep)++;
+ if (debugCastleSquares) {
+ for (Color c = WHITE; c <= BLACK; c++) {
+ if (can_castle_kingside(c) && piece_on(initial_kr_square(c)) != piece_of_color_and_type(c, ROOK))
+ return false;
+ if (can_castle_queenside(c) && piece_on(initial_qr_square(c)) != piece_of_color_and_type(c, ROOK))
+ return false;
+ }
+ if (castleRightsMask[initial_kr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OO))
+ return false;
+ if (castleRightsMask[initial_qr_square(WHITE)] != (ALL_CASTLES ^ WHITE_OOO))
+ return false;
+ if (castleRightsMask[initial_kr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OO))
+ return false;
+ if (castleRightsMask[initial_qr_square(BLACK)] != (ALL_CASTLES ^ BLACK_OOO))
+ return false;
+ }
+
if (failedStep) *failedStep = 0;
return true;
}