board.h

   1 #ifndef ZZGO_BOARD_H
   2 #define ZZGO_BOARD_H
   3
   4 #include <stdbool.h>
   5 #include <stdint.h>
   6
   7 #include "stone.h"
   8 #include "move.h"
   9
  10 #define likely(x) __builtin_expect(!!(x), 1)
  11 #define unlikely(x) __builtin_expect((x), 0)
  12
  13
  14 /* Allow board_play_random_move() to return pass even when
  15  * there are other moves available. */
  16 extern bool random_pass;
  17
  18
  19 typedef uint64_t hash_t;
  20
  21
  22 /* Note that "group" is only chain of stones that is solidly
  23  * connected for us. */
  24 typedef coord_t group_t;
  25
  26 struct neighbor_colors {
  27         char colors[S_MAX];
  28 };
  29
  30 /* You should treat this struct as read-only. Always call functions below if
  31  * you want to change it. */
  32
  33 struct board {
  34         int size; /* Including S_OFFBOARD margin - see below. */
  35         int size2; /* size^2 */
  36         int captures[S_MAX];
  37         float komi;
  38         int handicap;
  39
  40         int moves;
  41         struct move last_move;
  42         /* Whether we tried to add a hash twice; board_play*() can
  43          * set this, but it will still carry out the move as well! */
  44         bool superko_violation;
  45
  46         /* The following two structures are goban maps and are indexed by
  47          * coord.pos. The map is surrounded by a one-point margin from
  48          * S_OFFBOARD stones in order to speed up some internal loops.
  49          * Some of the foreach iterators below might include these points;
  50          * you need to handle them yourselves, if you need to. */
  51
  52         /* Stones played on the board */
  53         enum stone *b; /* enum stone */
  54         /* Group id the stones are part of; 0 == no group */
  55         group_t *g;
  56         /* Positions of next stones in the stone group; 0 == last stone */
  57         coord_t *p;
  58         /* Neighboring colors; numbers of neighbors of index color */
  59         struct neighbor_colors *n;
  60         /* Zobrist hash for each position */
  61         hash_t *h;
  62
  63         /* Group liberties - indexed by gid (which is coord of base group stone) */
  64         int *l;
  65
  66         /* Positions of free positions - queue (not map) */
  67         /* Note that free position here is any valid move; including single-point eyes! */
  68         coord_t *f; int flen;
  69
  70
  71         /* --- PRIVATE DATA --- */
  72
  73         /* Basic ko check */
  74         struct move ko;
  75
  76         /* For superko check: */
  77
  78         /* Board "history" - hashes encountered. Size of the hash should be
  79          * >> board_size^2. */
  80 #define history_hash_bits 12
  81 #define history_hash_mask ((1 << history_hash_bits) - 1)
  82         hash_t history_hash[1 << history_hash_bits];
  83         /* Hash of current board position. */
  84         hash_t hash;
  85 };
  86
  87 #define board_at(b_, c) ((b_)->b[coord_raw(c)])
  88 #define board_atxy(b_, x, y) ((b_)->b[(x) + (b_)->size * (y)])
  89
  90 #define group_at(b_, c) ((b_)->g[coord_raw(c)])
  91 #define group_atxy(b_, x, y) ((b_)->g[(x) + (b_)->size * (y)])
  92
  93 #define neighbor_count_at(b_, coord, color) ((b_)->n[coord_raw(coord)].colors[(enum stone) color])
  94 #define set_neighbor_count_at(b_, coord, color, count) (neighbor_count_at(b_, coord, color) = (count))
  95 #define inc_neighbor_count_at(b_, coord, color) (neighbor_count_at(b_, coord, color)++)
  96 #define dec_neighbor_count_at(b_, coord, color) (neighbor_count_at(b_, coord, color)--)
  97 #define immediate_liberty_count(b_, coord) (4 - neighbor_count_at(b_, coord, S_BLACK) - neighbor_count_at(b_, coord, S_WHITE) - neighbor_count_at(b_, coord, S_OFFBOARD))
  98
  99 #define groupnext_at(b_, c) ((b_)->p[coord_raw(c)])
 100 #define groupnext_atxy(b_, x, y) ((b_)->p[(x) + (b_)->size * (y)])
 101
 102 #define board_group_libs(b_, g_) ((b_)->l[(g_)])
 103 #define board_group_captured(b_, g_) (board_group_libs(b_, g_) == 0)
 104
 105 struct board *board_init(void);
 106 struct board *board_copy(struct board *board2, struct board *board1);
 107 void board_done_noalloc(struct board *board);
 108 void board_done(struct board *board);
 109 /* size here is without the S_OFFBOARD margin. */
 110 void board_resize(struct board *board, int size);
 111 void board_clear(struct board *board);
 112
 113 struct FILE;
 114 void board_print(struct board *board, FILE *f);
 115
 116 /* Place given handicap on the board; coordinates are printed to f. */
 117 void board_handicap(struct board *board, int stones, FILE *f);
 118
 119 /* Returns group id, 0 on allowed suicide, pass or resign, -1 on error */
 120 int board_play(struct board *board, struct move *m);
 121 /* Like above, but plays random move; the move coordinate is recorded
 122  * to *coord. This method will never fill your own eye. pass is played
 123  * when no move can be played. */
 124 void board_play_random(struct board *b, enum stone color, coord_t *coord);
 125
 126 /* Returns true if given coordinate has all neighbors of given color or the edge. */
 127 bool board_is_eyelike(struct board *board, coord_t *coord, enum stone eye_color);
 128 /* Returns true if given coordinate is a 1-pt eye (checks against false eyes, or
 129  * at least tries to). */
 130 bool board_is_one_point_eye(struct board *board, coord_t *c, enum stone eye_color);
 131 /* Returns color of a 1pt eye owner, S_NONE if not an eye. */
 132 enum stone board_get_one_point_eye(struct board *board, coord_t *c);
 133
 134 /* Check if group is in atari; this check can be potentially quite expensive!
 135  * The last liberty is recorded to lastlib (content is undefined if group
 136  * is not in atari). */
 137 bool board_group_in_atari(struct board *board, int group, coord_t *lastlib);
 138
 139 /* Positive: W wins */
 140 /* board_official_score() is the scoring method for yielding score suitable
 141  * for external presentation. For fast scoring of two Pachis playing,
 142  * use board_fast_score(). */
 143 float board_official_score(struct board *board);
 144 float board_fast_score(struct board *board);
 145
 146
 147 /** Iterators */
 148
 149 #define foreach_point(board_) \
 150         do { \
 151                 coord_t c; coord_pos(c, 0, (board_)); \
 152                 for (; coord_raw(c) < (board_)->size * (board_)->size; coord_raw(c)++)
 153 #define foreach_point_end \
 154         } while (0)
 155
 156 #define foreach_in_group(board_, group_) \
 157         do { \
 158                 struct board *board__ = board_; \
 159                 coord_t c = (group_); \
 160                 coord_t c2 = c; coord_raw(c2) = groupnext_at(board__, c2); \
 161                 do {
 162 #define foreach_in_group_end \
 163                         c = c2; coord_raw(c2) = groupnext_at(board__, c2); \
 164                 } while (coord_raw(c) != 0); \
 165         } while (0)
 166
 167 /* NOT VALID inside of foreach_point() or another foreach_neighbor(), or rather
 168  * on S_OFFBOARD coordinates. */
 169 #define foreach_neighbor(board_, coord_, loop_body) \
 170         do { \
 171                 struct board *board__ = board_; \
 172                 coord_t coord__ = coord_; \
 173                 coord_t c; \
 174                 coord_pos(c, coord_raw(coord__) - 1, (board__)); do { loop_body } while (0); \
 175                 coord_pos(c, coord_raw(coord__) - (board__)->size, (board__)); do { loop_body } while (0); \
 176                 coord_pos(c, coord_raw(coord__) + 1, (board__)); do { loop_body } while (0); \
 177                 coord_pos(c, coord_raw(coord__) + (board__)->size, (board__)); do { loop_body } while (0); \
 178         } while (0)
 179
 180 #define foreach_diag_neighbor(board_, coord_) \
 181         do { \
 182                 coord_t q__[4]; int q__i = 0; \
 183                 coord_pos(q__[q__i++], coord_raw(coord_) - (board_)->size - 1, (board_)); \
 184                 coord_pos(q__[q__i++], coord_raw(coord_) - (board_)->size + 1, (board_)); \
 185                 coord_pos(q__[q__i++], coord_raw(coord_) + (board_)->size - 1, (board_)); \
 186                 coord_pos(q__[q__i++], coord_raw(coord_) + (board_)->size + 1, (board_)); \
 187                 int fn__i; \
 188                 for (fn__i = 0; fn__i < q__i; fn__i++) { \
 189                         coord_t c = q__[fn__i];
 190 #define foreach_diag_neighbor_end \
 191                 } \
 192         } while (0)
 193
 194
 195 #endif