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 "pattern3.h"
  13 #include "tactics.h"
  14
  15
  16 struct pattern_config DEFAULT_PATTERN_CONFIG = {
  17         .spat_min = 3, .spat_max = MAX_PATTERN_DIST,
  18         .bdist_max = 4,
  19         .ldist_min = 0, .ldist_max = 256,
  20         .mcsims = 0, /* Unsupported. */
  21 };
  22
  23 struct pattern_config FAST_PATTERN_CONFIG = {
  24         .spat_min = 3, .spat_max = 3,
  25         .bdist_max = -1,
  26         .ldist_min = 0, .ldist_max = 256,
  27         .mcsims = 0,
  28 };
  29
  30 #define PF_MATCH 15
  31
  32 pattern_spec PATTERN_SPEC_MATCHALL = {
  33         [FEAT_PASS] = ~0,
  34         [FEAT_CAPTURE] = ~0,
  35         [FEAT_AESCAPE] = ~0,
  36         [FEAT_SELFATARI] = ~0,
  37         [FEAT_ATARI] = ~0,
  38         [FEAT_BORDER] = ~0,
  39         [FEAT_LDIST] = ~0,
  40         [FEAT_LLDIST] = ~0,
  41         [FEAT_CONTIGUITY] = 0,
  42         [FEAT_SPATIAL] = ~0,
  43         [FEAT_PATTERN3] = 0,
  44         [FEAT_MCOWNER] = ~0,
  45 };
  46
  47 /* !!! Note that in order for ELO playout policy to work correctly, this
  48  * pattern specification MUST exactly match the features matched by the
  49  * BOARD_GAMMA code! You cannot just tinker with this spec freely. */
  50 pattern_spec PATTERN_SPEC_MATCHFAST = {
  51         [FEAT_PASS] = 0,
  52         [FEAT_CAPTURE] = (1<<PF_MATCH | 1<<PF_CAPTURE_1STONE | 1<<PF_CAPTURE_TRAPPED | 1<<PF_CAPTURE_CONNECTION),
  53         [FEAT_AESCAPE] = (1<<PF_MATCH | 1<<PF_AESCAPE_1STONE | 1<<PF_AESCAPE_TRAPPED | 1<<PF_AESCAPE_CONNECTION),
  54         [FEAT_SELFATARI] = (1<<PF_MATCH | 1<<PF_SELFATARI_STUPID),
  55         [FEAT_ATARI] = 0,
  56         [FEAT_BORDER] = 0,
  57         [FEAT_LDIST] = 0,
  58         [FEAT_LLDIST] = 0,
  59         [FEAT_CONTIGUITY] = ~0,
  60         [FEAT_SPATIAL] = 0,
  61         [FEAT_PATTERN3] = ~0,
  62         [FEAT_MCOWNER] = 0,
  63 };
  64
  65 static const struct feature_info {
  66         char *name;
  67         int payloads;
  68 } features[FEAT_MAX] = {
  69         [FEAT_PASS] = { .name = "pass", .payloads = 2 },
  70         [FEAT_CAPTURE] = { .name = "capture", .payloads = 128 },
  71         [FEAT_AESCAPE] = { .name = "atariescape", .payloads = 16 },
  72         [FEAT_SELFATARI] = { .name = "selfatari", .payloads = 4 },
  73         [FEAT_ATARI] = { .name = "atari", .payloads = 4 },
  74         [FEAT_BORDER] = { .name = "border", .payloads = -1 },
  75         [FEAT_LDIST] = { .name = "ldist", .payloads = -1 },
  76         [FEAT_LLDIST] = { .name = "lldist", .payloads = -1 },
  77         [FEAT_CONTIGUITY] = { .name = "cont", .payloads = 2 },
  78         [FEAT_SPATIAL] = { .name = "s", .payloads = -1 },
  79         [FEAT_PATTERN3] = { .name = "p", .payloads = 2<<16 },
  80         [FEAT_MCOWNER] = { .name = "mcowner", .payloads = 16 },
  81 };
  82
  83 char *
  84 feature2str(char *str, struct feature *f)
  85 {
  86         return str + sprintf(str + strlen(str), "%s:%d", features[f->id].name, f->payload);
  87 }
  88
  89 char *
  90 str2feature(char *str, struct feature *f)
  91 {
  92         while (isspace(*str)) str++;
  93
  94         int unsigned flen = strcspn(str, ":");
  95         for (unsigned int i = 0; i < sizeof(features)/sizeof(features[0]); i++)
  96                 if (strlen(features[i].name) == flen && !strncmp(features[i].name, str, flen)) {
  97                         f->id = i;
  98                         goto found;
  99                 }
 100         fprintf(stderr, "invalid featurespec: %s[%d]\n", str, flen);
 101         exit(EXIT_FAILURE);
 102
 103 found:
 104         str += flen + 1;
 105         f->payload = strtoull(str, &str, 10);
 106         return str;
 107 }
 108
 109 char *
 110 feature_name(enum feature_id f)
 111 {
 112         return features[f].name;
 113 }
 114
 115 int
 116 feature_payloads(struct pattern_config *pc, enum feature_id f)
 117 {
 118         switch (f) {
 119                 case FEAT_SPATIAL:
 120                         assert(features[f].payloads < 0);
 121                         return pc->spat_dict->nspatials;
 122                 case FEAT_LDIST:
 123                 case FEAT_LLDIST:
 124                         assert(features[f].payloads < 0);
 125                         return pc->ldist_max + 1;
 126                 case FEAT_BORDER:
 127                         assert(features[f].payloads < 0);
 128                         return pc->bdist_max + 1;
 129                 default:
 130                         assert(features[f].payloads > 0);
 131                         return features[f].payloads;
 132         }
 133 }
 134
 135
 136 /* pattern_spec helpers */
 137 #define PS_ANY(F) (ps[FEAT_ ## F] & (1 << PF_MATCH))
 138 #define PS_PF(F, P) (ps[FEAT_ ## F] & (1 << PF_ ## F ## _ ## P))
 139
 140 //#undef BOARD_TRAITS // for cross-testing of pattern matchers - enable also elo_check_probdist()
 141
 142 static struct feature *
 143 pattern_match_capture(struct pattern_config *pc, pattern_spec ps,
 144                       struct pattern *p, struct feature *f,
 145                       struct board *b, struct move *m)
 146 {
 147         f->id = FEAT_CAPTURE; f->payload = 0;
 148 #ifdef BOARD_TRAITS
 149         if (!trait_at(b, m->coord, m->color).cap)
 150                 return f;
 151         /* Capturable! */
 152         if ((ps[FEAT_CAPTURE] & ~(1<<PF_CAPTURE_1STONE | 1<<PF_CAPTURE_TRAPPED | 1<<PF_CAPTURE_CONNECTION)) == 1<<PF_MATCH) {
 153                 if (PS_PF(CAPTURE, 1STONE))
 154                         f->payload |= (trait_at(b, m->coord, m->color).cap1 == trait_at(b, m->coord, m->color).cap) << PF_CAPTURE_1STONE;
 155                 if (PS_PF(CAPTURE, TRAPPED))
 156                         f->payload |= (!trait_at(b, m->coord, stone_other(m->color)).safe) << PF_CAPTURE_TRAPPED;
 157                 if (PS_PF(CAPTURE, CONNECTION))
 158                         f->payload |= (trait_at(b, m->coord, m->color).cap < neighbor_count_at(b, m->coord, stone_other(m->color))) << PF_CAPTURE_CONNECTION;
 159                 (f++, p->n++);
 160                 return f;
 161         }
 162         /* We need to know details, so we still have to go through
 163          * the neighbors. */
 164 #endif
 165
 166         /* We look at neighboring groups we could capture, and also if the
 167          * opponent could save them. */
 168         /* This is very similar in spirit to board_safe_to_play(), and almost
 169          * a color inverse of pattern_match_aescape(). */
 170
 171         /* Whether an escape move would be safe for the opponent. */
 172         int captures = 0;
 173         coord_t onelib = -1;
 174         int extra_libs = 0, connectable_groups = 0;
 175         bool onestone = false, multistone = false;
 176
 177         foreach_neighbor(b, m->coord, {
 178                 if (board_at(b, c) != stone_other(m->color)) {
 179                         if (board_at(b, c) == S_NONE)
 180                                 extra_libs++; // free point
 181                         else if (board_at(b, c) == m->color && board_group_info(b, group_at(b, c)).libs == 1)
 182                                 extra_libs += 2; // capturable enemy group
 183                         continue;
 184                 }
 185
 186                 group_t g = group_at(b, c); assert(g);
 187                 if (board_group_info(b, g).libs > 1) {
 188                         connectable_groups++;
 189                         if (board_group_info(b, g).libs > 2) {
 190                                 extra_libs += 2; // connected out
 191                         } else {
 192                                 /* This is a bit tricky; we connect our 2-lib
 193                                  * group to another 2-lib group, which counts
 194                                  * as one liberty, but only if the other lib
 195                                  * is not shared too. */
 196                                 if (onelib == -1) {
 197                                         onelib = board_group_other_lib(b, g, c);
 198                                         extra_libs++;
 199                                 } else {
 200                                         if (c == onelib)
 201                                                 extra_libs--; // take that back
 202                                         else
 203                                                 extra_libs++;
 204                                 }
 205                         }
 206                         continue;
 207                 }
 208
 209                 /* Capture! */
 210                 captures++;
 211
 212                 if (PS_PF(CAPTURE, LADDER))
 213                         f->payload |= is_ladder(b, m->coord, g, true, true) << PF_CAPTURE_LADDER;
 214                 /* TODO: is_ladder() is too conservative in some
 215                  * very obvious situations, look at complete.gtp. */
 216
 217                 /* TODO: PF_CAPTURE_RECAPTURE */
 218
 219                 if (PS_PF(CAPTURE, ATARIDEF))
 220                 foreach_in_group(b, g) {
 221                         foreach_neighbor(b, c, {
 222                                 assert(board_at(b, c) != S_NONE || c == m->coord);
 223                                 if (board_at(b, c) != m->color)
 224                                         continue;
 225                                 group_t g = group_at(b, c);
 226                                 if (!g || board_group_info(b, g).libs != 1)
 227                                         continue;
 228                                 /* A neighboring group of ours is in atari. */
 229                                 f->payload |= 1 << PF_CAPTURE_ATARIDEF;
 230                         });
 231                 } foreach_in_group_end;
 232
 233                 if (PS_PF(CAPTURE, KO)
 234                     && group_is_onestone(b, g)
 235                     && neighbor_count_at(b, m->coord, stone_other(m->color))
 236                        + neighbor_count_at(b, m->coord, S_OFFBOARD) == 4)
 237                         f->payload |= 1 << PF_CAPTURE_KO;
 238
 239                 if (group_is_onestone(b, g))
 240                         onestone = true;
 241                 else
 242                         multistone = true;
 243         });
 244
 245         if (captures > 0) {
 246                 if (PS_PF(CAPTURE, 1STONE))
 247                         f->payload |= (onestone && !multistone) << PF_CAPTURE_1STONE;
 248                 if (PS_PF(CAPTURE, TRAPPED))
 249                         f->payload |= (extra_libs < 2) << PF_CAPTURE_TRAPPED;
 250                 if (PS_PF(CAPTURE, CONNECTION))
 251                         f->payload |= (connectable_groups > 0) << PF_CAPTURE_CONNECTION;
 252                 (f++, p->n++);
 253         }
 254         return f;
 255 }
 256
 257 static struct feature *
 258 pattern_match_aescape(struct pattern_config *pc, pattern_spec ps,
 259                       struct pattern *p, struct feature *f,
 260                       struct board *b, struct move *m)
 261 {
 262         f->id = FEAT_AESCAPE; f->payload = 0;
 263 #ifdef BOARD_TRAITS
 264         if (!trait_at(b, m->coord, stone_other(m->color)).cap)
 265                 return f;
 266         /* Opponent can capture something! */
 267         if ((ps[FEAT_AESCAPE] & ~(1<<PF_AESCAPE_1STONE | 1<<PF_AESCAPE_TRAPPED | 1<<PF_AESCAPE_CONNECTION)) == 1<<PF_MATCH) {
 268                 if (PS_PF(AESCAPE, 1STONE))
 269                         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;
 270                 if (PS_PF(AESCAPE, TRAPPED))
 271                         f->payload |= (!trait_at(b, m->coord, m->color).safe) << PF_AESCAPE_TRAPPED;
 272                 if (PS_PF(AESCAPE, CONNECTION))
 273                         f->payload |= (trait_at(b, m->coord, stone_other(m->color)).cap < neighbor_count_at(b, m->coord, m->color)) << PF_AESCAPE_CONNECTION;
 274                 (f++, p->n++);
 275                 return f;
 276         }
 277         /* We need to know details, so we still have to go through
 278          * the neighbors. */
 279 #endif
 280
 281         /* Find if a neighboring group of ours is in atari, AND that we provide
 282          * a liberty to connect out. XXX: No connect-and-die check. */
 283         /* This is very similar in spirit to board_safe_to_play(). */
 284         group_t in_atari = -1;
 285         coord_t onelib = -1;
 286         int extra_libs = 0, connectable_groups = 0;
 287         bool onestone = false, multistone = false;
 288
 289         foreach_neighbor(b, m->coord, {
 290                 if (board_at(b, c) != m->color) {
 291                         if (board_at(b, c) == S_NONE)
 292                                 extra_libs++; // free point
 293                         else if (board_at(b, c) == stone_other(m->color) && board_group_info(b, group_at(b, c)).libs == 1) {
 294                                 extra_libs += 2; // capturable enemy group
 295                                 /* XXX: We just consider this move safe
 296                                  * unconditionally. */
 297                         }
 298                         continue;
 299                 }
 300                 group_t g = group_at(b, c); assert(g);
 301                 if (board_group_info(b, g).libs > 1) {
 302                         connectable_groups++;
 303                         if (board_group_info(b, g).libs > 2) {
 304                                 extra_libs += 2; // connected out
 305                         } else {
 306                                 /* This is a bit tricky; we connect our 2-lib
 307                                  * group to another 2-lib group, which counts
 308                                  * as one liberty, but only if the other lib
 309                                  * is not shared too. */
 310                                 if (onelib == -1) {
 311                                         onelib = board_group_other_lib(b, g, c);
 312                                         extra_libs++;
 313                                 } else {
 314                                         if (c == onelib)
 315                                                 extra_libs--; // take that back
 316                                         else
 317                                                 extra_libs++;
 318                                 }
 319                         }
 320                         continue;
 321                 }
 322
 323                 /* In atari! */
 324                 in_atari = g;
 325
 326                 if (PS_PF(AESCAPE, LADDER))
 327                         f->payload |= is_ladder(b, m->coord, g, true, true) << PF_AESCAPE_LADDER;
 328                 /* TODO: is_ladder() is too conservative in some
 329                  * very obvious situations, look at complete.gtp. */
 330
 331                 if (group_is_onestone(b, g))
 332                         onestone = true;
 333                 else
 334                         multistone = true;
 335         });
 336
 337         if (in_atari >= 0) {
 338                 if (PS_PF(AESCAPE, 1STONE))
 339                         f->payload |= (onestone && !multistone) << PF_AESCAPE_1STONE;
 340                 if (PS_PF(AESCAPE, TRAPPED))
 341                         f->payload |= (extra_libs < 2) << PF_AESCAPE_TRAPPED;
 342                 if (PS_PF(AESCAPE, CONNECTION))
 343                         f->payload |= (connectable_groups > 0) << PF_AESCAPE_CONNECTION;
 344                 (f++, p->n++);
 345         }
 346         return f;
 347 }
 348
 349 static struct feature *
 350 pattern_match_atari(struct pattern_config *pc, pattern_spec ps,
 351                     struct pattern *p, struct feature *f,
 352                     struct board *b, struct move *m)
 353 {
 354         foreach_neighbor(b, m->coord, {
 355                 if (board_at(b, c) != stone_other(m->color))
 356                         continue;
 357                 group_t g = group_at(b, c);
 358                 if (!g || board_group_info(b, g).libs != 2)
 359                         continue;
 360
 361                 /* Can atari! */
 362                 f->id = FEAT_ATARI; f->payload = 0;
 363
 364                 if (PS_PF(ATARI, LADDER)) {
 365                         /* Opponent will escape by the other lib. */
 366                         coord_t lib = board_group_other_lib(b, g, m->coord);
 367                         /* TODO: is_ladder() is too conservative in some
 368                          * very obvious situations, look at complete.gtp. */
 369                         f->payload |= is_ladder(b, lib, g, true, true) << PF_ATARI_LADDER;
 370                 }
 371
 372                 if (PS_PF(ATARI, KO) && !is_pass(b->ko.coord))
 373                         f->payload |= 1 << PF_ATARI_KO;
 374
 375                 (f++, p->n++);
 376         });
 377         return f;
 378 }
 379
 380 #ifndef BOARD_SPATHASH
 381 #undef BOARD_SPATHASH_MAXD
 382 #define BOARD_SPATHASH_MAXD 1
 383 #endif
 384
 385 /* Match spatial features that are too distant to be pre-matched
 386  * incrementally. */
 387 struct feature *
 388 pattern_match_spatial_outer(struct pattern_config *pc, pattern_spec ps,
 389                             struct pattern *p, struct feature *f,
 390                             struct board *b, struct move *m, hash_t h)
 391 {
 392         /* We record all spatial patterns black-to-play; simply
 393          * reverse all colors if we are white-to-play. */
 394         static enum stone bt_black[4] = { S_NONE, S_BLACK, S_WHITE, S_OFFBOARD };
 395         static enum stone bt_white[4] = { S_NONE, S_WHITE, S_BLACK, S_OFFBOARD };
 396         enum stone (*bt)[4] = m->color == S_WHITE ? &bt_white : &bt_black;
 397
 398         for (int d = BOARD_SPATHASH_MAXD + 1; d <= pc->spat_max; d++) {
 399                 /* Recompute missing outer circles:
 400                  * Go through all points in given distance. */
 401                 for (int j = ptind[d]; j < ptind[d + 1]; j++) {
 402                         ptcoords_at(x, y, m->coord, b, j);
 403                         h ^= pthashes[0][j][(*bt)[board_atxy(b, x, y)]];
 404                 }
 405                 if (d < pc->spat_min)
 406                         continue;
 407                 /* Record spatial feature, one per distance. */
 408                 int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 409                 if (sid > 0) {
 410                         f->id = FEAT_SPATIAL;
 411                         f->payload = sid;
 412                         (f++, p->n++);
 413                 } /* else not found, ignore */
 414         }
 415         return f;
 416 }
 417
 418 struct feature *
 419 pattern_match_spatial(struct pattern_config *pc, pattern_spec ps,
 420                       struct pattern *p, struct feature *f,
 421                       struct board *b, struct move *m)
 422 {
 423         /* XXX: This is partially duplicated from spatial_from_board(), but
 424          * we build a hash instead of spatial record. */
 425
 426         assert(pc->spat_min > 0);
 427
 428         hash_t h = pthashes[0][0][S_NONE];
 429 #ifdef BOARD_SPATHASH
 430         bool w_to_play = m->color == S_WHITE;
 431         for (int d = 2; d <= BOARD_SPATHASH_MAXD; d++) {
 432                 /* Reuse all incrementally matched data. */
 433                 h ^= b->spathash[m->coord][d - 1][w_to_play];
 434                 if (d < pc->spat_min)
 435                         continue;
 436                 /* Record spatial feature, one per distance. */
 437                 int sid = spatial_dict_get(pc->spat_dict, d, h & spatial_hash_mask);
 438                 if (sid > 0) {
 439                         f->id = FEAT_SPATIAL;
 440                         f->payload = sid;
 441                         (f++, p->n++);
 442                 } /* else not found, ignore */
 443         }
 444 #else
 445         assert(BOARD_SPATHASH_MAXD < 2);
 446 #endif
 447         if (unlikely(pc->spat_max > BOARD_SPATHASH_MAXD))
 448                 f = pattern_match_spatial_outer(pc, ps, p, f, b, m, h);
 449         return f;
 450 }
 451
 452
 453 void
 454 pattern_match(struct pattern_config *pc, pattern_spec ps,
 455               struct pattern *p, struct board *b, struct move *m)
 456 {
 457         p->n = 0;
 458         struct feature *f = &p->f[0];
 459
 460         /* TODO: We should match pretty much all of these features
 461          * incrementally. */
 462
 463         if (is_pass(m->coord)) {
 464                 if (PS_ANY(PASS)) {
 465                         f->id = FEAT_PASS; f->payload = 0;
 466                         if (PS_PF(PASS, LASTPASS))
 467                                 f->payload |= (b->moves > 0 && is_pass(b->last_move.coord))
 468                                                 << PF_PASS_LASTPASS;
 469                         p->n++;
 470                 }
 471                 return;
 472         }
 473
 474         if (PS_ANY(CAPTURE)) {
 475                 f = pattern_match_capture(pc, ps, p, f, b, m);
 476         }
 477
 478         if (PS_ANY(AESCAPE)) {
 479                 f = pattern_match_aescape(pc, ps, p, f, b, m);
 480         }
 481
 482         if (PS_ANY(SELFATARI)) {
 483                 bool simple = false;
 484                 if (PS_PF(SELFATARI, STUPID)) {
 485 #ifdef BOARD_TRAITS
 486                         if (!b->precise_selfatari)
 487                                 simple = !trait_at(b, m->coord, m->color).safe;
 488                         else
 489 #endif
 490                         simple = !board_safe_to_play(b, m->coord, m->color);
 491                 }
 492                 bool thorough = false;
 493                 if (PS_PF(SELFATARI, SMART)) {
 494 #ifdef BOARD_TRAITS
 495                         if (b->precise_selfatari)
 496                                 thorough = !trait_at(b, m->coord, m->color).safe;
 497                         else
 498 #endif
 499                         thorough = is_bad_selfatari(b, m->color, m->coord);
 500                 }
 501                 if (simple || thorough) {
 502                         f->id = FEAT_SELFATARI;
 503                         f->payload = simple << PF_SELFATARI_STUPID;
 504                         f->payload |= thorough << PF_SELFATARI_SMART;
 505                         (f++, p->n++);
 506                 }
 507         }
 508
 509         if (PS_ANY(ATARI)) {
 510                 f = pattern_match_atari(pc, ps, p, f, b, m);
 511         }
 512
 513         if (PS_ANY(BORDER)) {
 514                 int bdist = coord_edge_distance(m->coord, b);
 515                 if (bdist <= pc->bdist_max) {
 516                         f->id = FEAT_BORDER;
 517                         f->payload = bdist;
 518                         (f++, p->n++);
 519                 }
 520         }
 521
 522         if (PS_ANY(CONTIGUITY) && !is_pass(b->last_move.coord)
 523             && coord_is_8adjecent(m->coord, b->last_move.coord, b)) {
 524                 f->id = FEAT_CONTIGUITY;
 525                 f->payload = 1;
 526                 (f++, p->n++);
 527         }
 528
 529         if (PS_ANY(LDIST) && pc->ldist_max > 0 && !is_pass(b->last_move.coord)) {
 530                 int ldist = coord_gridcular_distance(m->coord, b->last_move.coord, b);
 531                 if (pc->ldist_min <= ldist && ldist <= pc->ldist_max) {
 532                         f->id = FEAT_LDIST;
 533                         f->payload = ldist;
 534                         (f++, p->n++);
 535                 }
 536         }
 537
 538         if (PS_ANY(LLDIST) && pc->ldist_max > 0 && !is_pass(b->last_move2.coord)) {
 539                 int lldist = coord_gridcular_distance(m->coord, b->last_move2.coord, b);
 540                 if (pc->ldist_min <= lldist && lldist <= pc->ldist_max) {
 541                         f->id = FEAT_LLDIST;
 542                         f->payload = lldist;
 543                         (f++, p->n++);
 544                 }
 545         }
 546
 547         if (PS_ANY(SPATIAL) && pc->spat_max > 0 && pc->spat_dict) {
 548                 f = pattern_match_spatial(pc, ps, p, f, b, m);
 549         }
 550
 551         if (PS_ANY(PATTERN3) && !is_pass(m->coord)) {
 552 #ifdef BOARD_PAT3
 553                 hash3_t pat = b->pat3[m->coord];
 554 #else
 555                 hash3_t pat = pattern3_hash(b, m->coord);
 556 #endif
 557                 if (m->color == S_WHITE) {
 558                         /* We work with the pattern3s as black-to-play. */
 559                         pat = pattern3_reverse(pat);
 560                 }
 561                 f->id = FEAT_PATTERN3;
 562                 f->payload = pat;
 563                 (f++, p->n++);
 564         }
 565
 566         /* FEAT_MCOWNER: TODO */
 567         assert(!pc->mcsims);
 568 }
 569
 570 char *
 571 pattern2str(char *str, struct pattern *p)
 572 {
 573         str = stpcpy(str, "(");
 574         for (int i = 0; i < p->n; i++) {
 575                 if (i > 0) str = stpcpy(str, " ");
 576                 str = feature2str(str, &p->f[i]);
 577         }
 578         str = stpcpy(str, ")");
 579         return str;
 580 }
 581
 582
 583
 584 /*** Features gamma set */
 585
 586 static void
 587 features_gamma_load(struct features_gamma *fg, const char *filename)
 588 {
 589         FILE *f = fopen(filename, "r");
 590         if (!f) return;
 591         char buf[256];
 592         while (fgets(buf, 256, f)) {
 593                 char *bufp = buf;
 594                 struct feature f;
 595                 bufp = str2feature(bufp, &f);
 596                 while (isspace(*bufp)) bufp++;
 597                 double gamma = strtod(bufp, &bufp);
 598                 /* Record feature's gamma. */
 599                 feature_gamma(fg, &f, &gamma);
 600                 /* In case of 3x3 patterns, record gamma also
 601                  * for all rotations and transpositions. */
 602                 if (f.id == FEAT_PATTERN3) {
 603                         hash3_t transp[8];
 604                         pattern3_transpose(f.payload, &transp);
 605                         for (int i = 1; i < 8; i++) {
 606                                 f.payload = transp[i];
 607                                 feature_gamma(fg, &f, &gamma);
 608                         }
 609                         f.payload = transp[0];
 610                 }
 611         }
 612         fclose(f);
 613 }
 614
 615 const char *features_gamma_filename = "patterns.gamma";
 616
 617 struct features_gamma *
 618 features_gamma_init(struct pattern_config *pc, const char *file)
 619 {
 620         struct features_gamma *fg = calloc2(1, sizeof(*fg));
 621         fg->pc = pc;
 622         for (int i = 0; i < FEAT_MAX; i++) {
 623                 int n = feature_payloads(pc, i);
 624                 fg->gamma[i] = malloc2(n * sizeof(fg->gamma[0][0]));
 625                 for (int j = 0; j < n; j++) {
 626                         fg->gamma[i][j] = 1.0f;
 627                 }
 628         }
 629         features_gamma_load(fg, file ? file : features_gamma_filename);
 630         return fg;
 631 }
 632
 633 void
 634 features_gamma_done(struct features_gamma *fg)
 635 {
 636         for (int i = 0; i < FEAT_MAX; i++)
 637                 free(fg->gamma[i]);
 638         free(fg);
 639 }