pattern.c

   1 #define DEBUG
   2 #include <assert.h>
   3 #include <ctype.h>
   4 #include <inttypes.h>
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7
   8 #include "board.h"
   9 #include "debug.h"
  10 #include "pattern.h"
  11 #include "patternsp.h"
  12 #include "patternprob.h"
  13 #include "tactics/ladder.h"
  14 #include "tactics/selfatari.h"
  15 #include "tactics/util.h"
  16
  17
  18 struct pattern_config DEFAULT_PATTERN_CONFIG = {
  19         .bdist_max = 4,
  20
  21         .spat_min = 3, .spat_max = MAX_PATTERN_DIST,
  22         .spat_largest = true,
  23 };
  24
  25 #define PF_MATCH 15
  26
  27 pattern_spec PATTERN_SPEC_MATCH_DEFAULT = {
  28         [FEAT_CAPTURE] = ~0,
  29         [FEAT_AESCAPE] = ~0,
  30         [FEAT_SELFATARI] = ~0,
  31         [FEAT_ATARI] = ~0,
  32         [FEAT_BORDER] = ~0,
  33         [FEAT_CONTIGUITY] = 0,
  34         [FEAT_SPATIAL] = ~0,
  35 };
  36
  37 static const struct feature_info {
  38         char *name;
  39         int payloads;
  40 } features[FEAT_MAX] = {
  41         [FEAT_CAPTURE] = { .name = "capture", .payloads = 64 },
  42         [FEAT_AESCAPE] = { .name = "atariescape", .payloads = 16 },
  43         [FEAT_SELFATARI] = { .name = "selfatari", .payloads = 4 },
  44         [FEAT_ATARI] = { .name = "atari", .payloads = 4 },
  45         [FEAT_BORDER] = { .name = "border", .payloads = -1 },
  46         [FEAT_CONTIGUITY] = { .name = "cont", .payloads = 2 },
  47         [FEAT_SPATIAL] = { .name = "s", .payloads = -1 },
  48 };
  49
  50 char *
  51 feature2str(char *str, struct feature *f)
  52 {
  53         return str + sprintf(str + strlen(str), "%s:%d", features[f->id].name, f->payload);
  54 }
  55
  56 char *
  57 str2feature(char *str, struct feature *f)
  58 {
  59         while (isspace(*str)) str++;
  60
  61         int unsigned flen = strcspn(str, ":");
  62         for (unsigned int i = 0; i < sizeof(features)/sizeof(features[0]); i++)
  63                 if (strlen(features[i].name) == flen && !strncmp(features[i].name, str, flen)) {
  64                         f->id = i;
  65                         goto found;
  66                 }
  67         fprintf(stderr, "invalid featurespec: %s[%d]\n", str, flen);
  68         exit(EXIT_FAILURE);
  69
  70 found:
  71         str += flen + 1;
  72         f->payload = strtoull(str, &str, 10);
  73         return str;
  74 }
  75
  76 char *
  77 feature_name(enum feature_id f)
  78 {
  79         return features[f].name;
  80 }
  81
  82 int
  83 feature_payloads(struct pattern_config *pc, enum feature_id f)
  84 {
  85         switch (f) {
  86                 case FEAT_SPATIAL:
  87                         assert(features[f].payloads < 0);
  88                         return pc->spat_dict->nspatials;
  89                 case FEAT_BORDER:
  90                         assert(features[f].payloads < 0);
  91                         return pc->bdist_max + 1;
  92                 default:
  93                         assert(features[f].payloads > 0);
  94                         return features[f].payloads;
  95         }
  96 }
  97
  98
  99 void
 100 patterns_init(struct pattern_setup *pat, bool will_append, bool load_prob)
 101 {
 102         memset(pat, 0, sizeof(*pat));
 103
 104         pat->pc = DEFAULT_PATTERN_CONFIG;
 105         pat->pc.spat_dict = spatial_dict_init(will_append, !load_prob);
 106
 107         memcpy(&pat->ps, PATTERN_SPEC_MATCH_DEFAULT, sizeof(pattern_spec));
 108
 109         if (load_prob && pat->pc.spat_dict) {
 110                 pat->pd = pattern_pdict_init(NULL, &pat->pc);
 111         }
 112 }
 113
 114
 115 /* pattern_spec helpers */
 116 #define PS_ANY(F) (ps[FEAT_ ## F] & (1 << PF_MATCH))
 117 #define PS_PF(F, P) (ps[FEAT_ ## F] & (1 << PF_ ## F ## _ ## P))
 118
 119 static struct feature *
 120 pattern_match_capture(struct pattern_config *pc, pattern_spec ps,
 121                       struct pattern *p, struct feature *f,
 122                       struct board *b, struct move *m)
 123 {
 124         f->id = FEAT_CAPTURE; f->payload = 0;
 125 #ifdef BOARD_TRAITS
 126         if (!trait_at(b, m->coord, m->color).cap)
 127                 return f;
 128         /* Capturable! */
 129         if ((ps[FEAT_CAPTURE] & ~(1<<PF_CAPTURE_1STONE | 1<<PF_CAPTURE_TRAPPED | 1<<PF_CAPTURE_CONNECTION)) == 1<<PF_MATCH) {
 130                 if (PS_PF(CAPTURE, 1STONE))
 131                         f->payload |= (trait_at(b, m->coord, m->color).cap1 == trait_at(b, m->coord, m->color).cap) << PF_CAPTURE_1STONE;
 132                 if (PS_PF(CAPTURE, TRAPPED))
 133                         f->payload |= (!trait_at(b, m->coord, stone_other(m->color)).safe) << PF_CAPTURE_TRAPPED;
 134                 if (PS_PF(CAPTURE, CONNECTION))
 135                         f->payload |= (trait_at(b, m->coord, m->color).cap < neighbor_count_at(b, m->coord, stone_other(m->color))) << PF_CAPTURE_CONNECTION;
 136                 (f++, p->n++);
 137                 return f;
 138         }
 139         /* We need to know details, so we still have to go through
 140          * the neighbors. */
 141 #endif
 142
 143         /* We look at neighboring groups we could capture, and also if the
 144          * opponent could save them. */
 145         /* This is very similar in spirit to board_safe_to_play(), and almost
 146          * a color inverse of pattern_match_aescape(). */
 147
 148         /* Whether an escape move would be safe for the opponent. */
 149         int captures = 0;
 150         coord_t onelib = -1;
 151         int extra_libs = 0, connectable_groups = 0;
 152         bool onestone = false, multistone = false;
 153
 154         foreach_neighbor(b, m->coord, {
 155                 if (board_at(b, c) != stone_other(m->color)) {
 156                         if (board_at(b, c) == S_NONE)
 157                                 extra_libs++; // free point
 158                         else if (board_at(b, c) == m->color && board_group_info(b, group_at(b, c)).libs == 1)
 159                                 extra_libs += 2; // capturable enemy group
 160                         continue;
 161                 }
 162
 163                 group_t g = group_at(b, c); assert(g);
 164                 if (board_group_info(b, g).libs > 1) {
 165                         connectable_groups++;
 166                         if (board_group_info(b, g).libs > 2) {
 167                                 extra_libs += 2; // connected out
 168                         } else {
 169                                 /* This is a bit tricky; we connect our 2-lib
 170                                  * group to another 2-lib group, which counts
 171                                  * as one liberty, but only if the other lib
 172                                  * is not shared too. */
 173                                 if (onelib == -1) {
 174                                         onelib = board_group_other_lib(b, g, c);
 175                                         extra_libs++;
 176                                 } else {
 177                                         if (c == onelib)
 178                                                 extra_libs--; // take that back
 179                                         else
 180                                                 extra_libs++;
 181                                 }
 182                         }
 183                         continue;
 184                 }
 185
 186                 /* Capture! */
 187                 captures++;
 188
 189                 if (PS_PF(CAPTURE, LADDER))
 190                         f->payload |= is_ladder(b, m->coord, g) << PF_CAPTURE_LADDER;
 191                 /* TODO: is_ladder() is too conservative in some
 192                  * very obvious situations, look at complete.gtp. */
 193
 194                 if (PS_PF(CAPTURE, ATARIDEF))
 195                 foreach_in_group(b, g) {
 196                         foreach_neighbor(b, c, {
 197                                 assert(board_at(b, c) != S_NONE || c == m->coord);
 198                                 if (board_at(b, c) != m->color)
 199                                         continue;
 200                                 group_t g = group_at(b, c);
 201                                 if (!g || board_group_info(b, g).libs != 1)
 202                                         continue;
 203                                 /* A neighboring group of ours is in atari. */
 204                                 f->payload |= 1 << PF_CAPTURE_ATARIDEF;
 205                         });
 206                 } foreach_in_group_end;
 207
 208                 if (PS_PF(CAPTURE, KO)
 209                     && group_is_onestone(b, g)
 210                     && neighbor_count_at(b, m->coord, stone_other(m->color))
 211                        + neighbor_count_at(b, m->coord, S_OFFBOARD) == 4)
 212                         f->payload |= 1 << PF_CAPTURE_KO;
 213
 214                 if (group_is_onestone(b, g))
 215                         onestone = true;
 216                 else
 217                         multistone = true;
 218         });
 219
 220         if (captures > 0) {
 221                 if (PS_PF(CAPTURE, 1STONE))
 222                         f->payload |= (onestone && !multistone) << PF_CAPTURE_1STONE;
 223                 if (PS_PF(CAPTURE, TRAPPED))
 224                         f->payload |= (extra_libs < 2) << PF_CAPTURE_TRAPPED;
 225                 if (PS_PF(CAPTURE, CONNECTION))
 226                         f->payload |= (connectable_groups > 0) << PF_CAPTURE_CONNECTION;
 227                 (f++, p->n++);
 228         }
 229         return f;
 230 }
 231
 232 static struct feature *
 233 pattern_match_aescape(struct pattern_config *pc, pattern_spec ps,
 234                       struct pattern *p, struct feature *f,
 235                       struct board *b, struct move *m)
 236 {
 237         f->id = FEAT_AESCAPE; f->payload = 0;
 238 #ifdef BOARD_TRAITS
 239         if (!trait_at(b, m->coord, stone_other(m->color)).cap)
 240                 return f;
 241         /* Opponent can capture something! */
 242         if ((ps[FEAT_AESCAPE] & ~(1<<PF_AESCAPE_1STONE | 1<<PF_AESCAPE_TRAPPED | 1<<PF_AESCAPE_CONNECTION)) == 1<<PF_MATCH) {
 243                 if (PS_PF(AESCAPE, 1STONE))
 244                         f->payload |= (trait_at(b, m->coord, stone_other(m->color)).cap1 == trait_at(b, m->coord, stone_other(m->color)).cap) << PF_AESCAPE_1STONE;
 245                 if (PS_PF(AESCAPE, TRAPPED))
 246                         f->payload |= (!trait_at(b, m->coord, m->color).safe) << PF_AESCAPE_TRAPPED;
 247                 if (PS_PF(AESCAPE, CONNECTION))
 248                         f->payload |= (trait_at(b, m->coord, stone_other(m->color)).cap < neighbor_count_at(b, m->coord, m->color)) << PF_AESCAPE_CONNECTION;
 249                 (f++, p->n++);
 250                 return f;
 251         }
 252         /* We need to know details, so we still have to go through
 253          * the neighbors. */
 254 #endif
 255
 256         /* Find if a neighboring group of ours is in atari, AND that we provide
 257          * a liberty to connect out. XXX: No connect-and-die check. */
 258         /* This is very similar in spirit to board_safe_to_play(). */
 259         group_t in_atari = -1;
 260         coord_t onelib = -1;
 261         int extra_libs = 0, connectable_groups = 0;
 262         bool onestone = false, multistone = false;
 263
 264         foreach_neighbor(b, m->coord, {
 265                 if (board_at(b, c) != m->color) {
 266                         if (board_at(b, c) == S_NONE)
 267                                 extra_libs++; // free point
 268                         else if (board_at(b, c) == stone_other(m->color) && board_group_info(b, group_at(b, c)).libs == 1) {
 269                                 extra_libs += 2; // capturable enemy group
 270                                 /* XXX: We just consider this move safe
 271                                  * unconditionally. */
 272                         }
 273                         continue;
 274                 }
 275                 group_t g = group_at(b, c); assert(g);
 276                 if (board_group_info(b, g).libs > 1) {
 277                         connectable_groups++;
 278                         if (board_group_info(b, g).libs > 2) {
 279                                 extra_libs += 2; // connected out
 280                         } else {
 281                                 /* This is a bit tricky; we connect our 2-lib
 282                                  * group to another 2-lib group, which counts
 283                                  * as one liberty, but only if the other lib
 284                                  * is not shared too. */
 285                                 if (onelib == -1) {
 286                                         onelib = board_group_other_lib(b, g, c);
 287                                         extra_libs++;
 288                                 } else {
 289                                         if (c == onelib)
 290                                                 extra_libs--; // take that back
 291                                         else
 292                                                 extra_libs++;
 293                                 }
 294                         }
 295                         continue;
 296                 }
 297
 298                 /* In atari! */
 299                 in_atari = g;
 300
 301                 if (PS_PF(AESCAPE, LADDER))
 302                         f->payload |= is_ladder(b, m->coord, g) << PF_AESCAPE_LADDER;
 303                 /* TODO: is_ladder() is too conservative in some
 304                  * very obvious situations, look at complete.gtp. */
 305
 306                 if (group_is_onestone(b, g))
 307                         onestone = true;
 308                 else
 309                         multistone = true;
 310         });
 311
 312         if (in_atari >= 0) {
 313                 if (PS_PF(AESCAPE, 1STONE))
 314                         f->payload |= (onestone && !multistone) << PF_AESCAPE_1STONE;
 315                 if (PS_PF(AESCAPE, TRAPPED))
 316                         f->payload |= (extra_libs < 2) << PF_AESCAPE_TRAPPED;
 317                 if (PS_PF(AESCAPE, CONNECTION))
 318                         f->payload |= (connectable_groups > 0) << PF_AESCAPE_CONNECTION;
 319                 (f++, p->n++);
 320         }
 321         return f;
 322 }
 323
 324 static struct feature *
 325 pattern_match_atari(struct pattern_config *pc, pattern_spec ps,
 326                     struct pattern *p, struct feature *f,
 327                     struct board *b, struct move *m)
 328 {
 329         foreach_neighbor(b, m->coord, {
 330                 if (board_at(b, c) != stone_other(m->color))
 331                         continue;
 332                 group_t g = group_at(b, c);
 333                 if (!g || board_group_info(b, g).libs != 2)
 334                         continue;
 335
 336                 /* Can atari! */
 337                 f->id = FEAT_ATARI; f->payload = 0;
 338
 339                 if (PS_PF(ATARI, LADDER)) {
 340                         /* Opponent will escape by the other lib. */
 341                         coord_t lib = board_group_other_lib(b, g, m->coord);
 342                         /* TODO: is_ladder() is too conservative in some
 343                          * very obvious situations, look at complete.gtp. */
 344                         f->payload |= is_ladder(b, lib, g) << PF_ATARI_LADDER;
 345                 }
 346
 347                 if (PS_PF(ATARI, KO) && !is_pass(b->ko.coord))
 348                         f->payload |= 1 << PF_ATARI_KO;
 349
 350                 (f++, p->n++);
 351         });
 352         return f;
 353 }
 354
 355 #ifndef BOARD_SPATHASH
 356 #undef BOARD_SPATHASH_MAXD
 357 #define BOARD_SPATHASH_MAXD 1
 358 #endif
 359
 360 /* Match spatial features that are too distant to be pre-matched
 361  * incrementally. */
 362 struct feature *
 363 pattern_match_spatial_outer(struct pattern_config *pc, pattern_spec ps,
 364                             struct pattern *p, struct feature *f,
 365                             struct board *b, struct move *m, hash_t h)
 366 {
 367         /* We record all spatial patterns black-to-play; simply
 368          * reverse all colors if we are white-to-play. */
 369         static enum stone bt_black[4] = { S_NONE, S_BLACK, S_WHITE, S_OFFBOARD };
 370         static enum stone bt_white[4] = { S_NONE, S_WHITE, S_BLACK, S_OFFBOARD };
 371         enum stone (*bt)[4] = m->color == S_WHITE ? &bt_white : &bt_black;
 372
 373         for (int d = BOARD_SPATHASH_MAXD + 1; d <= pc->spat_max; d++) {
 374                 /* Recompute missing outer circles:
 375                  * Go through all points in given distance. */
 376                 for (int j = ptind[d]; j < ptind[d + 1]; j++) {
 377                         ptcoords_at(x, y, m->coord, b, j);
 378                         h ^= pthashes[0][j][(*bt)[board_atxy(b, x, y)]];
 379                 }
 380                 if (d < pc->spat_min)
 381                         continue;
 382                 /* Record spatial feature, one per distance. */
 383                 unsigned int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 384                 if (sid > 0) {
 385                         f->id = FEAT_SPATIAL;
 386                         f->payload = sid;
 387                         if (!pc->spat_largest)
 388                                 (f++, p->n++);
 389                 } /* else not found, ignore */
 390         }
 391         return f;
 392 }
 393
 394 struct feature *
 395 pattern_match_spatial(struct pattern_config *pc, pattern_spec ps,
 396                       struct pattern *p, struct feature *f,
 397                       struct board *b, struct move *m)
 398 {
 399         /* XXX: This is partially duplicated from spatial_from_board(), but
 400          * we build a hash instead of spatial record. */
 401
 402         assert(pc->spat_min > 0);
 403         f->id = -1;
 404
 405         hash_t h = pthashes[0][0][S_NONE];
 406 #ifdef BOARD_SPATHASH
 407         bool w_to_play = m->color == S_WHITE;
 408         for (int d = 2; d <= BOARD_SPATHASH_MAXD; d++) {
 409                 /* Reuse all incrementally matched data. */
 410                 h ^= b->spathash[m->coord][d - 1][w_to_play];
 411                 if (d < pc->spat_min)
 412                         continue;
 413                 /* Record spatial feature, one per distance. */
 414                 unsigned int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 415                 if (sid > 0) {
 416                         f->id = FEAT_SPATIAL;
 417                         f->payload = sid;
 418                         if (!pc->spat_largest)
 419                                 (f++, p->n++);
 420                 } /* else not found, ignore */
 421         }
 422 #else
 423         assert(BOARD_SPATHASH_MAXD < 2);
 424 #endif
 425         if (unlikely(pc->spat_max > BOARD_SPATHASH_MAXD))
 426                 f = pattern_match_spatial_outer(pc, ps, p, f, b, m, h);
 427         if (pc->spat_largest && f->id == FEAT_SPATIAL)
 428                 (f++, p->n++);
 429         return f;
 430 }
 431
 432
 433 void
 434 pattern_match(struct pattern_config *pc, pattern_spec ps,
 435               struct pattern *p, struct board *b, struct move *m)
 436 {
 437         p->n = 0;
 438         struct feature *f = &p->f[0];
 439
 440         /* TODO: We should match pretty much all of these features
 441          * incrementally. */
 442
 443         if (PS_ANY(CAPTURE)) {
 444                 f = pattern_match_capture(pc, ps, p, f, b, m);
 445         }
 446
 447         if (PS_ANY(AESCAPE)) {
 448                 f = pattern_match_aescape(pc, ps, p, f, b, m);
 449         }
 450
 451         if (PS_ANY(SELFATARI)) {
 452                 bool simple = false;
 453                 if (PS_PF(SELFATARI, STUPID)) {
 454 #ifdef BOARD_TRAITS
 455                         if (!b->precise_selfatari)
 456                                 simple = !trait_at(b, m->coord, m->color).safe;
 457                         else
 458 #endif
 459                         simple = !board_safe_to_play(b, m->coord, m->color);
 460                 }
 461                 bool thorough = false;
 462                 if (PS_PF(SELFATARI, SMART)) {
 463 #ifdef BOARD_TRAITS
 464                         if (b->precise_selfatari)
 465                                 thorough = !trait_at(b, m->coord, m->color).safe;
 466                         else
 467 #endif
 468                         thorough = is_bad_selfatari(b, m->color, m->coord);
 469                 }
 470                 if (simple || thorough) {
 471                         f->id = FEAT_SELFATARI;
 472                         f->payload = simple << PF_SELFATARI_STUPID;
 473                         f->payload |= thorough << PF_SELFATARI_SMART;
 474                         (f++, p->n++);
 475                 }
 476         }
 477
 478         if (PS_ANY(ATARI)) {
 479                 f = pattern_match_atari(pc, ps, p, f, b, m);
 480         }
 481
 482         if (PS_ANY(BORDER)) {
 483                 int bdist = coord_edge_distance(m->coord, b);
 484                 if (bdist <= pc->bdist_max) {
 485                         f->id = FEAT_BORDER;
 486                         f->payload = bdist;
 487                         (f++, p->n++);
 488                 }
 489         }
 490
 491         if (PS_ANY(CONTIGUITY) && !is_pass(b->last_move.coord)
 492             && coord_is_8adjecent(m->coord, b->last_move.coord, b)) {
 493                 f->id = FEAT_CONTIGUITY;
 494                 f->payload = 1;
 495                 (f++, p->n++);
 496         }
 497
 498         if (PS_ANY(SPATIAL) && pc->spat_max > 0 && pc->spat_dict) {
 499                 f = pattern_match_spatial(pc, ps, p, f, b, m);
 500         }
 501 }
 502
 503 char *
 504 pattern2str(char *str, struct pattern *p)
 505 {
 506         str = stpcpy(str, "(");
 507         for (int i = 0; i < p->n; i++) {
 508                 if (i > 0) str = stpcpy(str, " ");
 509                 str = feature2str(str, &p->f[i]);
 510         }
 511         str = stpcpy(str, ")");
 512         return str;
 513 }
 514
 515 char *
 516 str2pattern(char *str, struct pattern *p)
 517 {
 518         p->n = 0;
 519         while (isspace(*str)) str++;
 520         if (*str++ != '(') {
 521                 fprintf(stderr, "invalid patternspec: %s\n", str);
 522                 exit(EXIT_FAILURE);
 523         }
 524
 525         while (*str != ')') {
 526                 str = str2feature(str, &p->f[p->n++]);
 527         }
 528
 529         str++;
 530         return str;
 531 }