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add bitboard_print_multi(), file/rank/diag/antidiag masks generation

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This commit is contained in:
Bruno Raoult
2024-02-12 21:34:42 +01:00
parent d5906b1fb9
commit 3e828ed29b
5 changed files with 125 additions and 14 deletions
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113
src/bitboard.c
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@@ -12,6 +12,7 @@
*/
#include <stdio.h>
#include <stdarg.h>
#include "brlib.h"
@@ -30,9 +31,18 @@ static int king_vector[8] = {
NORTH, NORTH_EAST, EAST, SOUTH_EAST,
SOUTH, SOUTH_WEST, WEST, NORTH_WEST
};
static int bishop_vector[4] = {
NORTH_EAST, SOUTH_EAST, SOUTH_WEST, NORTH_WEST
};
static int rook_vector[4] = {
NORTH, EAST, SOUTH, WEST
};
bitboard_t sq_bb[SQUARE_MAX];
bitboard_t sq_bbrank[64], sq_bbfile[64], sq_bbdiag[64], sq_bbanti[64];
bitboard_t knight_attacks[64], king_attacks[64];
bitboard_t pawn_attacks[2];
/* we will create only dest squares for A1-D4 square, then flip
*/
@@ -44,11 +54,55 @@ bitboard_t knight_attacks[64], king_attacks[64];
*/
void bitboard_init(void)
{
square_t sq, dst;
struct {
union {
struct {
bitboard_t diag;
bitboard_t anti;
bitboard_t vert;
bitboard_t hori;
};
bitboard_t all[4];
};
} tmpmasks[64] = {0};
struct {
int df, dr;
} dirs[4] = {
{ 0, 1 }, /* vertical/file */
{ 1, 0 }, /* horizontal/rank */
{ 1, 1 }, /* diagonal */
{ 1, -1 }, /* antidiagonal */
} ;
square_t sq;
int dst, dst_f, dst_r;
/* square to bitboard */
for (sq = A1; sq <= H8; ++sq)
sq_bb[sq] = mask(sq);
/* square to rank/file/diagonal/antidiagonal */
for (sq = 0; sq < 64; ++sq) {
int r = sq_rank(sq), f = sq_file(sq);
for (int mult = -7; mult < 8; ++mult) {
for (int dir = 0; dir < 4; ++dir) {
dst_f = f + mult * dirs[dir].df;
dst_r = r + mult * dirs[dir].dr;
if (sq_coord_ok(dst_f) && sq_coord_ok(dst_r)) {
dst = sq_make(dst_f, dst_r);
tmpmasks[sq].all[dir] |= mask(dst);
}
}
}
}
for (sq = 0; sq < 64; ++sq) {
sq_bbfile[sq] = tmpmasks[sq].all[0];
sq_bbrank[sq] = tmpmasks[sq].all[1];
sq_bbdiag[sq] = tmpmasks[sq].all[2];
sq_bbanti[sq] = tmpmasks[sq].all[3];
}
/* knight and king attacks */
for (sq = A1; sq <= H8; ++sq) {
for (int vec = 0; vec < 8; ++vec) {
dst = sq + knight_vector[vec];
@@ -69,21 +123,62 @@ void bitboard_init(void)
/**
* bitboard_print() - print simple bitboard representation
* @bb: the bitboard
* @tit: a string or NULL
* @title: a string or NULL
* @bitboard: the bitboard
*/
void bitboard_print(const bitboard_t bb, const char *tit)
void bitboard_print(const char *title, const bitboard_t bitboard)
{
//char c = p? p: 'X';
if (tit)
printf("%s\n", tit);
if (title)
printf("%s\n", title);
for (rank_t r = RANK_8; r >= RANK_1; --r) {
printf("%d ", r);
printf("%d ", r + 1);
for (file_t f = FILE_A; f <= FILE_H; ++f) {
printf(" %c", bb & sq_bb[sq_make(f, r)] ? 'X': '.');
printf(" %c", bitboard & sq_bb[sq_make(f, r)] ? 'X': '.');
}
printf("\n");
}
printf("\n A B C D E F G H\n");
printf(" a b c d e f g h\n");
return;
}
/**
* bitboard_print_multi() - print multiple bitboards horizontally
* @title: a string or NULL
* @n: number of bitboards
* @bb_ptr...: pointers to bitboards
*
* @n is the number of bitboards to print. If @n -s > 8, it is reduced to 8;
*/
void bitboard_print_multi(const char *title, const int n, ...)
{
bitboard_t bb[16];
int i;
va_list ap;
va_start(ap, n);
for (i = 0; i < n; ++i) {
bb[i] = va_arg(ap, bitboard_t);
}
va_end(ap);
//char c = p? p: 'X';
if (title)
printf("%s\n", title);
for (rank_t r = RANK_8; r >= RANK_1; --r) {
for (i = 0; i < n; ++i) {
printf("%d ", r + 1);
for (file_t f = FILE_A; f <= FILE_H; ++f) {
printf(" %c", bb[i] & sq_bb[sq_make(f, r)] ? 'X': '.');
}
printf(" ");
}
printf("\n");
}
for (i = 0; i < n; ++i) {
printf(" a b c d e f g h");
printf(" ");
}
printf("\n");
return;
}

11
src/bitboard.h
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@@ -22,7 +22,13 @@
typedef u64 bitboard_t;
extern bitboard_t sq_bb[64], knight_attacks[64], king_attacks[64];
/* mapping square -> bitboard */
extern bitboard_t sq_bb[64];
/* mapping square -> rank/file/diagonal/antidiagonal */
extern bitboard_t sq_bbrank[64], sq_bbfile[64], sq_bbdiag[64], sq_bbanti[64];
extern bitboard_t knight_attacks[64], king_attacks[64];
#define mask(i) ( 1ULL << (i) )
@@ -56,6 +62,7 @@ static __always_inline bitboard_t bb_rotate_90(bitboard_t b)
}
extern void bitboard_init(void);
extern void bitboard_print(const bitboard_t bitboard, const char *title);
extern void bitboard_print(const char *title, const bitboard_t bitboard);
extern void bitboard_print_multi(const char *title, const int n, ...);
#endif /* _BITBOARD_H */

1
src/board.h
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@@ -80,6 +80,7 @@ static __always_inline rank_t sq_rank(square_t square)
#define sq_ok(sq) ((sq) >= A1 && (sq) <= H8)
#define sq_coord_ok(c) ((c) >= 0 && (c) < 8)
/* Chebyshev distance: https://www.chessprogramming.org/Distance */
#define sq_dist(sq1, sq2) (max(abs(sq_file(sq2) - sq_file(sq1)), \

2
src/move.c
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@@ -14,7 +14,7 @@
#include <malloc.h>
#include <ctype.h>
#include <br.h>
#include <brlib.h>
#include <list.h>
#include <list_sort.h>
#include <debug.h>

12
test/bitboard-test.c
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@@ -13,11 +13,19 @@ int main(int __unused ac, __unused char**av)
{
char str[128];
bitboard_init();
for (int i = 0; i < 64; ++i) {
char str[128];
sprintf(str, "\ndiag/antidiag/vert %d", i);
bitboard_print_multi(str, 5,
sq_bbfile[i] | sq_bbrank[i] | sq_bbdiag[i] | sq_bbanti[i],
sq_bbfile[i], sq_bbrank[i],
sq_bbdiag[i], sq_bbanti[i]);
}
for (square_t sq = 0; sq < 64; ++sq) {
sprintf(str, "%2d %#lx %#lx knight", sq, sq_bb[sq], knight_attacks[sq]);
bitboard_print(knight_attacks[sq], str);
bitboard_print(str, knight_attacks[sq]);
sprintf(str, "%2d %#lx %#lx knight", sq, sq_bb[sq], king_attacks[sq]);
bitboard_print(king_attacks[sq], str);
bitboard_print(str, king_attacks[sq]);
}
return 0;
}