11 #define likely(x) __builtin_expect(!!(x), 1)
12 #define unlikely(x) __builtin_expect((x), 0)
15 /* The board implementation has bunch of optional features.
16 * Turn them on below: */
17 #define WANT_BOARD_C // required by playout_moggy
18 //#define BOARD_SIZE 9 // constant board size, allows better optimization
21 /* Allow board_play_random_move() to return pass even when
22 * there are other moves available. */
23 extern bool random_pass
;
26 /* Some engines might normalize their reading and skip symmetrical
27 * moves. We will tell them how can they do it. */
28 struct board_symmetry
{
29 /* Playground is in this rectangle. */
31 /* d == 0: Full rectangle
32 * d == 1: Top triangle */
34 /* General symmetry type. */
35 /* Note that the above is redundant to this, but just provided
36 * for easier usage. */
48 typedef uint64_t hash_t
;
49 #define PRIhash PRIx64
52 /* Note that "group" is only chain of stones that is solidly
53 * connected for us. */
54 typedef coord_t group_t
;
57 /* We keep track of only up to GROUP_KEEP_LIBS; over that, we
59 /* _Combination_ of these two values can make some difference
60 * in performance - fine-tune. */
61 #define GROUP_KEEP_LIBS 10
62 // refill lib[] only when we hit this; this must be at least 2!
63 // Moggy requires at least 3 - see below for semantic impact.
64 #define GROUP_REFILL_LIBS 5
65 coord_t lib
[GROUP_KEEP_LIBS
];
66 /* libs is only LOWER BOUND for the number of real liberties!!!
67 * It denotes only number of items in lib[], thus you can rely
68 * on it to store real liberties only up to <= GROUP_REFILL_LIBS. */
72 struct neighbor_colors
{
76 /* You should treat this struct as read-only. Always call functions below if
77 * you want to change it. */
80 int size
; /* Including S_OFFBOARD margin - see below. */
81 int size2
; /* size^2 */
87 struct move last_move
;
88 struct move last_move2
; /* second-to-last move */
89 /* Whether we tried to add a hash twice; board_play*() can
90 * set this, but it will still carry out the move as well! */
91 bool superko_violation
;
93 /* The following two structures are goban maps and are indexed by
94 * coord.pos. The map is surrounded by a one-point margin from
95 * S_OFFBOARD stones in order to speed up some internal loops.
96 * Some of the foreach iterators below might include these points;
97 * you need to handle them yourselves, if you need to. */
99 /* Stones played on the board */
100 enum stone
*b
; /* enum stone */
101 /* Group id the stones are part of; 0 == no group */
103 /* Positions of next stones in the stone group; 0 == last stone */
105 /* Neighboring colors; numbers of neighbors of index color */
106 struct neighbor_colors
*n
;
107 /* Zobrist hash for each position */
110 /* Group information - indexed by gid (which is coord of base group stone) */
113 /* Positions of free positions - queue (not map) */
114 /* Note that free position here is any valid move; including single-point eyes! */
115 coord_t
*f
; int flen
;
118 /* Queue of capturable groups */
119 group_t
*c
; int clen
;
122 /* Symmetry information */
123 struct board_symmetry symmetry
;
125 /* Last ko played on the board. */
132 /* Engine-specific state; persistent through board development,
133 * is reset only at clear_board. */
137 /* --- PRIVATE DATA --- */
139 /* For superko check: */
141 /* Board "history" - hashes encountered. Size of the hash should be
142 * >> board_size^2. */
143 #define history_hash_bits 12
144 #define history_hash_mask ((1 << history_hash_bits) - 1)
145 #define history_hash_prev(i) ((i - 1) & history_hash_mask)
146 #define history_hash_next(i) ((i + 1) & history_hash_mask)
147 hash_t history_hash
[1 << history_hash_bits
];
148 /* Hash of current board position. */
153 /* Avoid unused variable warnings */
154 #define board_size(b_) (((b_) == (b_)) ? BOARD_SIZE + 2 : 0)
155 #define board_size2(b_) (board_size(b_) * board_size(b_))
157 #define board_size(b_) ((b_)->size)
158 #define board_size2(b_) ((b_)->size2)
161 #define board_at(b_, c) ((b_)->b[coord_raw(c)])
162 #define board_atxy(b_, x, y) ((b_)->b[(x) + board_size(b_) * (y)])
164 #define group_at(b_, c) ((b_)->g[coord_raw(c)])
165 #define group_atxy(b_, x, y) ((b_)->g[(x) + board_size(b_) * (y)])
167 /* Warning! Neighbor count is kept up-to-date for S_NONE! */
168 #define neighbor_count_at(b_, coord, color) ((b_)->n[coord_raw(coord)].colors[(enum stone) color])
169 #define set_neighbor_count_at(b_, coord, color, count) (neighbor_count_at(b_, coord, color) = (count))
170 #define inc_neighbor_count_at(b_, coord, color) (neighbor_count_at(b_, coord, color)++)
171 #define dec_neighbor_count_at(b_, coord, color) (neighbor_count_at(b_, coord, color)--)
172 #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))
174 #define groupnext_at(b_, c) ((b_)->p[coord_raw(c)])
175 #define groupnext_atxy(b_, x, y) ((b_)->p[(x) + board_size(b_) * (y)])
177 #define group_base(g_) (g_)
178 #define board_group_info(b_, g_) ((b_)->gi[(g_)])
179 #define board_group_captured(b_, g_) (board_group_info(b_, g_).libs == 0)
180 #define group_is_onestone(b_, g_) (groupnext_at(b_, group_base(g_)) == 0)
182 #define hash_at(b_, coord, color) ((b_)->h[((color) == S_BLACK ? board_size2(b_) : 0) + coord_raw(coord)])
184 struct board
*board_init(void);
185 struct board
*board_copy(struct board
*board2
, struct board
*board1
);
186 void board_done_noalloc(struct board
*board
);
187 void board_done(struct board
*board
);
188 /* size here is without the S_OFFBOARD margin. */
189 void board_resize(struct board
*board
, int size
);
190 /* The caller must take care of releasing board.es first. */
191 void board_clear(struct board
*board
);
194 typedef void (*board_cprint
)(struct board
*b
, coord_t c
, FILE *f
);
195 void board_print(struct board
*board
, FILE *f
);
196 void board_print_custom(struct board
*board
, FILE *f
, board_cprint cprint
);
198 /* Place given handicap on the board; coordinates are printed to f. */
199 void board_handicap(struct board
*board
, int stones
, FILE *f
);
201 /* Returns group id, 0 on allowed suicide, pass or resign, -1 on error */
202 int board_play(struct board
*board
, struct move
*m
);
203 /* Like above, but plays random move; the move coordinate is recorded
204 * to *coord. This method will never fill your own eye. pass is played
205 * when no move can be played. You can impose extra restrictions if you
206 * supply your own permit function. */
207 typedef bool (*ppr_permit
)(void *data
, struct board
*b
, struct move
*m
);
208 void board_play_random(struct board
*b
, enum stone color
, coord_t
*coord
, ppr_permit permit
, void *permit_data
);
210 /* Returns true if given move can be played. */
211 static bool board_is_valid_move(struct board
*b
, struct move
*m
);
212 /* Returns true if ko was just taken. */
213 static bool board_playing_ko_threat(struct board
*b
);
215 /* Adjust symmetry information as if given coordinate has been played. */
216 void board_symmetry_update(struct board
*b
, struct board_symmetry
*symmetry
, coord_t c
);
218 /* Returns true if given coordinate has all neighbors of given color or the edge. */
219 static bool board_is_eyelike(struct board
*board
, coord_t
*coord
, enum stone eye_color
);
220 /* Returns true if given coordinate could be a false eye; this check makes
221 * sense only if you already know the coordinate is_eyelike(). */
222 bool board_is_false_eyelike(struct board
*board
, coord_t
*coord
, enum stone eye_color
);
223 /* Returns true if given coordinate is a 1-pt eye (checks against false eyes, or
224 * at least tries to). */
225 bool board_is_one_point_eye(struct board
*board
, coord_t
*c
, enum stone eye_color
);
226 /* Returns color of a 1pt eye owner, S_NONE if not an eye. */
227 enum stone
board_get_one_point_eye(struct board
*board
, coord_t
*c
);
229 /* board_official_score() is the scoring method for yielding score suitable
230 * for external presentation. For fast scoring of entirely filled boards
231 * (e.g. playouts), use board_fast_score(). */
232 /* Positive: W wins */
233 /* Compare number of stones + 1pt eyes. */
234 float board_fast_score(struct board
*board
);
235 /* Tromp-Taylor scoring, assuming given groups are actually dead. */
237 float board_official_score(struct board
*board
, struct move_queue
*mq
);
242 #define foreach_point(board_) \
244 coord_t c; coord_pos(c, 0, (board_)); \
245 for (; coord_raw(c) < board_size(board_) * board_size(board_); coord_raw(c)++)
246 #define foreach_point_and_pass(board_) \
248 coord_t c; coord_pos(c, -1, (board_)); \
249 for (; coord_raw(c) < board_size(board_) * board_size(board_); coord_raw(c)++)
250 #define foreach_point_end \
253 #define foreach_in_group(board_, group_) \
255 struct board *board__ = board_; \
256 coord_t c = group_base(group_); \
257 coord_t c2 = c; coord_raw(c2) = groupnext_at(board__, c2); \
259 #define foreach_in_group_end \
260 c = c2; coord_raw(c2) = groupnext_at(board__, c2); \
261 } while (coord_raw(c) != 0); \
264 /* NOT VALID inside of foreach_point() or another foreach_neighbor(), or rather
265 * on S_OFFBOARD coordinates. */
266 #define foreach_neighbor(board_, coord_, loop_body) \
268 struct board *board__ = board_; \
269 coord_t coord__ = coord_; \
271 coord_pos(c, coord_raw(coord__) - 1, (board__)); do { loop_body } while (0); \
272 coord_pos(c, coord_raw(coord__) - board_size(board__), (board__)); do { loop_body } while (0); \
273 coord_pos(c, coord_raw(coord__) + 1, (board__)); do { loop_body } while (0); \
274 coord_pos(c, coord_raw(coord__) + board_size(board__), (board__)); do { loop_body } while (0); \
277 #define foreach_8neighbor(board_, coord_) \
279 coord_t q__[8]; int q__i = 0; \
280 coord_pos(q__[q__i++], coord_raw(coord_) - board_size(board_) - 1, (board_)); \
281 coord_pos(q__[q__i++], coord_raw(coord_) - board_size(board_), (board_)); \
282 coord_pos(q__[q__i++], coord_raw(coord_) - board_size(board_) + 1, (board_)); \
283 coord_pos(q__[q__i++], coord_raw(coord_) - 1, (board_)); \
284 coord_pos(q__[q__i++], coord_raw(coord_) + 1, (board_)); \
285 coord_pos(q__[q__i++], coord_raw(coord_) + board_size(board_) - 1, (board_)); \
286 coord_pos(q__[q__i++], coord_raw(coord_) + board_size(board_), (board_)); \
287 coord_pos(q__[q__i++], coord_raw(coord_) + board_size(board_) + 1, (board_)); \
289 for (fn__i = 0; fn__i < q__i; fn__i++) { \
290 coord_t c = q__[fn__i];
291 #define foreach_8neighbor_end \
295 #define foreach_diag_neighbor(board_, coord_) \
297 coord_t q__[4]; int q__i = 0; \
298 coord_pos(q__[q__i++], coord_raw(coord_) - board_size(board_) - 1, (board_)); \
299 coord_pos(q__[q__i++], coord_raw(coord_) - board_size(board_) + 1, (board_)); \
300 coord_pos(q__[q__i++], coord_raw(coord_) + board_size(board_) - 1, (board_)); \
301 coord_pos(q__[q__i++], coord_raw(coord_) + board_size(board_) + 1, (board_)); \
303 for (fn__i = 0; fn__i < q__i; fn__i++) { \
304 coord_t c = q__[fn__i];
305 #define foreach_diag_neighbor_end \
311 board_is_eyelike(struct board
*board
, coord_t
*coord
, enum stone eye_color
)
313 return (neighbor_count_at(board
, *coord
, eye_color
)
314 + neighbor_count_at(board
, *coord
, S_OFFBOARD
)) == 4;
318 board_is_valid_move(struct board
*board
, struct move
*m
)
320 if (board_at(board
, m
->coord
) != S_NONE
)
322 if (!board_is_eyelike(board
, &m
->coord
, stone_other(m
->color
)))
324 /* Play within {true,false} eye-ish formation */
325 if (board
->ko
.coord
== m
->coord
&& board
->ko
.color
== m
->color
)
327 int groups_in_atari
= 0;
328 foreach_neighbor(board
, m
->coord
, {
329 group_t g
= group_at(board
, c
);
330 groups_in_atari
+= (board_group_info(board
, g
).libs
== 1);
332 return !!groups_in_atari
;
336 board_playing_ko_threat(struct board
*b
)
338 return !is_pass(b
->ko
.coord
);