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