/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-#if !defined(BITBOARD_H_INCLUDED)
+#ifndef BITBOARD_H_INCLUDED
#define BITBOARD_H_INCLUDED
#include "types.h"
namespace Bitboards {
void init();
-void print(Bitboard b);
+const std::string pretty(Bitboard b);
}
extern Bitboard InFrontBB[COLOR_NB][RANK_NB];
extern Bitboard StepAttacksBB[PIECE_NB][SQUARE_NB];
extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
+extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
extern Bitboard DistanceRingsBB[SQUARE_NB][8];
extern Bitboard ForwardBB[COLOR_NB][SQUARE_NB];
extern Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB];
extern Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB];
extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
-const Bitboard BlackSquares = 0xAA55AA55AA55AA55ULL;
+extern int SquareDistance[SQUARE_NB][SQUARE_NB];
+
+const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
/// Overloads of bitwise operators between a Bitboard and a Square for testing
/// whether a given bit is set in a bitboard, and for setting and clearing bits.
return b ^ SquareBB[s];
}
-
-/// more_than_one() returns true if in 'b' there is more than one bit set
-
inline bool more_than_one(Bitboard b) {
return b & (b - 1);
}
+inline int square_distance(Square s1, Square s2) {
+ return SquareDistance[s1][s2];
+}
+
+inline int file_distance(Square s1, Square s2) {
+ return abs(file_of(s1) - file_of(s2));
+}
+
+inline int rank_distance(Square s1, Square s2) {
+ return abs(rank_of(s1) - rank_of(s2));
+}
+
/// shift_bb() moves bitboard one step along direction Delta. Mainly for pawns.
}
-/// adjacent_files_bb takes a file as input and returns a bitboard representing
+/// adjacent_files_bb() takes a file as input and returns a bitboard representing
/// all squares on the adjacent files.
inline Bitboard adjacent_files_bb(File f) {
}
-/// between_bb returns a bitboard representing all squares between two squares.
+/// between_bb() returns a bitboard representing all squares between two squares.
/// For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with the bits for
/// square d5 and e6 set. If s1 and s2 are not on the same line, file or diagonal,
/// 0 is returned.
}
-/// forward_bb takes a color and a square as input, and returns a bitboard
+/// forward_bb() takes a color and a square as input, and returns a bitboard
/// representing all squares along the line in front of the square, from the
/// point of view of the given color. Definition of the table is:
/// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s)
}
-/// passed_pawn_mask takes a color and a square as input, and returns a
+/// pawn_attack_span() 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:
+/// PawnAttackSpan[c][s] = in_front_bb(c, s) & adjacent_files_bb(s);
+
+inline Bitboard pawn_attack_span(Color c, Square s) {
+ return PawnAttackSpan[c][s];
+}
+
+
+/// passed_pawn_mask() takes a color and a square as input, and returns a
/// bitboard mask which can be used to test if a pawn of the given color on
/// the given square is a passed pawn. Definition of the table is:
-/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(s)
+/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_bb(c, s)
inline Bitboard passed_pawn_mask(Color c, Square s) {
return PassedPawnMask[c][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) & adjacent_files_bb(s);
+/// squares_of_color() returns a bitboard representing all squares with the same
+/// color of the given square.
-inline Bitboard pawn_attack_span(Color c, Square s) {
- return PawnAttackSpan[c][s];
+inline Bitboard squares_of_color(Square s) {
+ return DarkSquares & s ? DarkSquares : ~DarkSquares;
}
-/// squares_aligned returns true if the squares s1, s2 and s3 are aligned
+/// aligned() returns true if the squares s1, s2 and s3 are aligned
/// either on a straight or on a diagonal line.
-inline bool squares_aligned(Square s1, Square s2, Square s3) {
- return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3])
- & ( SquareBB[s1] | SquareBB[s2] | SquareBB[s3]);
-}
-
-
-/// same_color_squares() returns a bitboard representing all squares with
-/// the same color of the given square.
-
-inline Bitboard same_color_squares(Square s) {
- return BlackSquares & s ? BlackSquares : ~BlackSquares;
+inline bool aligned(Square s1, Square s2, Square s3) {
+ return LineBB[s1][s2] & s3;
}
return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index<Pt>(s, occ)];
}
+inline Bitboard attacks_bb(Piece p, Square s, Bitboard occ) {
-/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard.
-/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard.
+ switch (type_of(p))
+ {
+ case BISHOP: return attacks_bb<BISHOP>(s, occ);
+ case ROOK : return attacks_bb<ROOK>(s, occ);
+ case QUEEN : return attacks_bb<BISHOP>(s, occ) | attacks_bb<ROOK>(s, occ);
+ default : return StepAttacksBB[p][s];
+ }
+}
-#if defined(USE_BSFQ)
+/// lsb()/msb() finds the least/most significant bit in a non-zero bitboard.
+/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard.
+
+#ifdef USE_BSFQ
# if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
return s;
}
-#else // if !defined(USE_BSFQ)
+#else // if defined(USE_BSFQ)
extern Square msb(Bitboard b);
extern Square lsb(Bitboard b);
#endif
-#endif // !defined(BITBOARD_H_INCLUDED)
+/// frontmost_sq() and backmost_sq() find 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); }
+
+#endif // #ifndef BITBOARD_H_INCLUDED
projects / stockfish / blobdiff