constexpr Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB;
constexpr Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB);
+constexpr Bitboard KingFlank[FILE_NB] = {
+ QueenSide ^ FileDBB, QueenSide, QueenSide,
+ CenterFiles, CenterFiles,
+ KingSide, KingSide, KingSide ^ FileEBB
+};
+
extern uint8_t PopCnt16[1 << 16];
extern uint8_t SquareDistance[SQUARE_NB][SQUARE_NB];
+extern Bitboard SquareBB[SQUARE_NB];
extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
extern Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
-extern Bitboard KingFlank[FILE_NB];
-extern Bitboard SquareBB[SQUARE_NB];
/// Magic holds all magic bitboards relevant data for a single square
template<Direction D>
constexpr Bitboard shift(Bitboard b) {
return D == NORTH ? b << 8 : D == SOUTH ? b >> 8
+ : D == NORTH+NORTH? b <<16 : D == SOUTH+SOUTH? b >>16
: D == EAST ? (b & ~FileHBB) << 1 : D == WEST ? (b & ~FileABB) >> 1
: D == NORTH_EAST ? (b & ~FileHBB) << 9 : D == NORTH_WEST ? (b & ~FileABB) << 7
: D == SOUTH_EAST ? (b & ~FileHBB) >> 7 : D == SOUTH_WEST ? (b & ~FileABB) >> 9
/// adjacent_files_bb() returns a bitboard representing all the squares on the
/// adjacent files of the given one.
-inline Bitboard adjacent_files_bb(File f) {
- return shift<EAST>(file_bb(f)) | shift<WEST>(file_bb(f));
+inline Bitboard adjacent_files_bb(Square s) {
+ return shift<EAST>(file_bb(s)) | shift<WEST>(file_bb(s));
}
/// starting from the given square.
inline Bitboard pawn_attack_span(Color c, Square s) {
- return forward_ranks_bb(c, s) & adjacent_files_bb(file_of(s));
+ return forward_ranks_bb(c, s) & adjacent_files_bb(s);
}
/// the given color and on the given square is a passed pawn.
inline Bitboard passed_pawn_span(Color c, Square s) {
- return forward_ranks_bb(c, s) & (adjacent_files_bb(file_of(s)) | file_bb(s));
+ return forward_ranks_bb(c, s) & (adjacent_files_bb(s) | file_bb(s));
}
}
-/// frontmost_sq() and backmost_sq() return the square corresponding to the
-/// most/least advanced bit relative to the given color.
-
-inline Square frontmost_sq(Color c, Bitboard b) { return c == WHITE ? msb(b) : lsb(b); }
-inline Square backmost_sq(Color c, Bitboard b) { return c == WHITE ? lsb(b) : msb(b); }
+/// frontmost_sq() returns the most advanced square for the given color
+inline Square frontmost_sq(Color c, Bitboard b) {
+ return c == WHITE ? msb(b) : lsb(b);
+}
#endif // #ifndef BITBOARD_H_INCLUDED