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