//// Includes
////
-#include "direction.h"
#include "piece.h"
#include "square.h"
#include "types.h"
//// Constants and variables
////
-const Bitboard EmptyBoardBB = 0ULL;
-
-const Bitboard WhiteSquaresBB = 0x55AA55AA55AA55AAULL;
-const Bitboard BlackSquaresBB = 0xAA55AA55AA55AA55ULL;
+const Bitboard EmptyBoardBB = 0;
const Bitboard FileABB = 0x0101010101010101ULL;
-const Bitboard FileBBB = 0x0202020202020202ULL;
-const Bitboard FileCBB = 0x0404040404040404ULL;
-const Bitboard FileDBB = 0x0808080808080808ULL;
-const Bitboard FileEBB = 0x1010101010101010ULL;
-const Bitboard FileFBB = 0x2020202020202020ULL;
-const Bitboard FileGBB = 0x4040404040404040ULL;
-const Bitboard FileHBB = 0x8080808080808080ULL;
-
-const Bitboard Rank1BB = 0xFFULL;
-const Bitboard Rank2BB = 0xFF00ULL;
-const Bitboard Rank3BB = 0xFF0000ULL;
-const Bitboard Rank4BB = 0xFF000000ULL;
-const Bitboard Rank5BB = 0xFF00000000ULL;
-const Bitboard Rank6BB = 0xFF0000000000ULL;
-const Bitboard Rank7BB = 0xFF000000000000ULL;
-const Bitboard Rank8BB = 0xFF00000000000000ULL;
+const Bitboard FileBBB = FileABB << 1;
+const Bitboard FileCBB = FileABB << 2;
+const Bitboard FileDBB = FileABB << 3;
+const Bitboard FileEBB = FileABB << 4;
+const Bitboard FileFBB = FileABB << 5;
+const Bitboard FileGBB = FileABB << 6;
+const Bitboard FileHBB = FileABB << 7;
+
+const Bitboard Rank1BB = 0xFF;
+const Bitboard Rank2BB = Rank1BB << (8 * 1);
+const Bitboard Rank3BB = Rank1BB << (8 * 2);
+const Bitboard Rank4BB = Rank1BB << (8 * 3);
+const Bitboard Rank5BB = Rank1BB << (8 * 4);
+const Bitboard Rank6BB = Rank1BB << (8 * 5);
+const Bitboard Rank7BB = Rank1BB << (8 * 6);
+const Bitboard Rank8BB = Rank1BB << (8 * 7);
extern const Bitboard SquaresByColorBB[2];
extern const Bitboard FileBB[8];
extern Bitboard SetMaskBB[65];
extern Bitboard ClearMaskBB[65];
-extern Bitboard StepAttackBB[16][64];
-extern Bitboard RayBB[64][8];
+extern Bitboard NonSlidingAttacksBB[16][64];
extern Bitboard BetweenBB[64][64];
extern Bitboard SquaresInFrontMask[2][64];
extern Bitboard PassedPawnMask[2][64];
-extern Bitboard OutpostMask[2][64];
+extern Bitboard AttackSpanMask[2][64];
extern const uint64_t RMult[64];
extern const int RShift[64];
*b ^= move_bb;
}
-/// rank_bb() and file_bb() gives a bitboard containing all squares on a given
-/// file or rank. It is also possible to pass a square as input to these
-/// functions.
+/// rank_bb() and file_bb() take a file or a square as input, and return
+/// a bitboard representing all squares on the given file or rank.
inline Bitboard rank_bb(Rank r) {
return RankBB[r];
}
-/// ray_bb() gives a bitboard representing all squares along the ray in a
-/// given direction from a given square.
-
-inline Bitboard ray_bb(Square s, SignedDirection d) {
- return RayBB[s][d];
-}
-
-
/// Functions for computing sliding attack bitboards. rook_attacks_bb(),
/// bishop_attacks_bb() and queen_attacks_bb() all take a square and a
/// bitboard of occupied squares as input, and return a bitboard representing
}
-/// outpost_mask takes a color and a square as input, and returns a bitboard
-/// mask which can be used to test whether a piece on the square can possibly
-/// be driven away by an enemy pawn. Definition of the table is:
-/// OutpostMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
+/// attack_span_mask takes a color and a square as input, and returns a bitboard
+/// representing all squares that can be attacked by a pawn of the given color
+/// when it moves along its file starting from the given square. Definition is:
+/// AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
+
+inline Bitboard attack_span_mask(Color c, Square s) {
+ return AttackSpanMask[c][s];
+}
+
+
+/// squares_aligned returns true if the squares s1, s2 and s3 are aligned
+/// either on a straight or on a diagonal line.
-inline Bitboard outpost_mask(Color c, Square s) {
- return OutpostMask[c][s];
+inline bool squares_aligned(Square s1, Square s2, Square s3) {
+ return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3])
+ & ((1ULL << s1) | (1ULL << s2) | (1ULL << s3));
}
extern void print_bitboard(Bitboard b);
extern void init_bitboards();
-extern int bitScanReverse32(uint32_t b);
#endif // !defined(BITBOARD_H_INCLUDED)