playout/moggy.c

   1 #include <assert.h>
   2 #include <math.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5
   6 #define DEBUG
   7 #include "board.h"
   8 #include "debug.h"
   9 #include "playout.h"
  10 #include "playout/moggy.h"
  11 #include "random.h"
  12
  13 #define PLDEBUGL(n) DEBUGL_(p->debug_level, n)
  14
  15
  16 struct moggy_policy {
  17         bool ladders, ladderassess, borderladders;
  18         int lcapturerate, capturerate, patternrate;
  19         int selfatarirate;
  20 };
  21
  22 #define MQL 64
  23 struct move_queue {
  24         int moves;
  25         coord_t move[MQL];
  26 };
  27
  28 static void
  29 mq_nodup(struct move_queue *q)
  30 {
  31         if ((q->moves > 1 && q->move[q->moves - 2] == q->move[q->moves - 1])
  32             || (q->moves > 2 && q->move[q->moves - 3] == q->move[q->moves - 1])
  33             || (q->moves > 3 && q->move[q->moves - 4] == q->move[q->moves - 1]))
  34                 q->moves--;
  35 }
  36
  37
  38 /* Pattern encoding:
  39  * X: black;  O: white;  .: empty;  #: edge
  40  * x: !black; o: !white; ?: any
  41  *
  42  * extra X: pattern valid only for one side;
  43  * middle point ignored. */
  44
  45 static char moggy_patterns_src[][11] = {
  46         /* hane pattern - enclosing hane */
  47         "XOX"
  48         "..."
  49         "???",
  50         /* hane pattern - non-cutting hane */
  51         "XO."
  52         "..."
  53         "?.?",
  54         /* hane pattern - magari */
  55         "XO?"
  56         "X.."
  57         "x.?",
  58         /* hane pattern - thin hane */
  59         "XOO"
  60         "..."
  61         "?.?" "X",
  62         /* generic pattern - katatsuke or diagonal attachment; similar to magari */
  63         ".O."
  64         "X.."
  65         "...",
  66         /* cut1 pattern (kiri) - unprotected cut */
  67         "XO?"
  68         "O.o"
  69         "?o?",
  70         /* cut1 pattern (kiri) - peeped cut */
  71         "XO?"
  72         "O.X"
  73         "???",
  74         /* cut2 pattern (de) */
  75         "?X?"
  76         "O.O"
  77         "ooo",
  78         /* cut keima (not in Mogo) */
  79         "OX?"
  80         "o.O"
  81         "o??",
  82         /* side pattern - chase */
  83         "X.?"
  84         "O.?"
  85         "##?",
  86         /* side pattern - weirdness (SUSPICIOUS) */
  87         "?X?"
  88         "X.O"
  89         "###",
  90         /* side pattern - sagari (SUSPICIOUS) */
  91         "?XO"
  92         "x.x" /* Mogo has "x.?" */
  93         "###" /* Mogo has "X" */,
  94         /* side pattern - weirdcut (SUSPICIOUS) */
  95 #if 0
  96         "?OX"
  97         "?.O"
  98         "?##" "X",
  99 #endif
 100         /* side pattern - cut (SUSPICIOUS) */
 101         "?OX"
 102         "X.O"
 103         "###" /* Mogo has "X" */,
 104 };
 105 #define moggy_patterns_src_n sizeof(moggy_patterns_src) / sizeof(moggy_patterns_src[0])
 106
 107 /* Hashtable: 2*8 bits (ignore middle point, 2 bits per intersection) */
 108 /* Value: 0: no pattern, 1: black pattern, 2: white pattern, 3: both patterns */
 109 static char moggy_patterns[65536];
 110
 111 static void
 112 _record_pattern(char *table, char *str, int pat, int fixed_color)
 113 {
 114         /* Original color assignment */
 115         table[pat] = fixed_color ? fixed_color : 3;
 116         //fprintf(stderr, "[%s] %04x %d\n", str, pat, fixed_color);
 117
 118         /* Reverse color assignment - achieved by swapping odd and even bits */
 119         pat = ((pat >> 1) & 0x5555) | ((pat & 0x5555) << 1);
 120         table[pat] = fixed_color ? 2 - (fixed_color == 2) : 3;
 121         //fprintf(stderr, "[%s] %04x %d\n", str, pat, fixed_color);
 122 }
 123
 124 static int
 125 _pat_vmirror(int pat)
 126 {
 127         /* V mirror pattern; reverse order of 3-2-3 chunks */
 128         return ((pat & 0xfc00) >> 10) | (pat & 0x03c0) | ((pat & 0x003f) << 10);
 129 }
 130
 131 static int
 132 _pat_hmirror(int pat)
 133 {
 134         /* H mirror pattern; reverse order of 2-bit values within the chunks */
 135 #define rev3(p) ((p >> 4) | (p & 0xc) | ((p & 0x3) << 4))
 136 #define rev2(p) ((p >> 2) | ((p & 0x3) << 2))
 137         return (rev3((pat & 0xfc00) >> 10) << 10)
 138                 | (rev2((pat & 0x03c0) >> 6) << 6)
 139                 | rev3((pat & 0x003f));
 140 #undef rev3
 141 #undef rev2
 142 }
 143
 144 static int
 145 _pat_90rot(int pat)
 146 {
 147         /* Rotate by 90 degrees:
 148          * 5 6 7    7 4 2
 149          * 3   4 -> 6   1
 150          * 0 1 2    5 3 0 */
 151         /* I'm too lazy to optimize this :) */
 152         int vals[8];
 153         for (int i = 0; i < 8; i++)
 154                 vals[i] = (pat >> (i * 2)) & 0x3;
 155         int vals2[8];
 156         vals2[0] = vals[5]; vals2[1] = vals[3]; vals2[2] = vals[0];
 157         vals2[3] = vals[6];                     vals2[4] = vals[1];
 158         vals2[5] = vals[7]; vals2[6] = vals[4]; vals2[7] = vals[2];
 159         int p2 = 0;
 160         for (int i = 0; i < 8; i++)
 161                 p2 |= vals2[i] << (i * 2);
 162         return p2;
 163 }
 164
 165 static void
 166 _gen_pattern(char *table, int pat, char *src, int srclen, int fixed_color)
 167 {
 168         for (; srclen > 0; src++, srclen--) {
 169                 if (srclen == 5)
 170                         continue;
 171                 int patofs = (srclen > 5 ? srclen - 1 : srclen) - 1;
 172                 switch (*src) {
 173                         case '?':
 174                                 *src = '.'; _gen_pattern(table, pat, src, srclen, fixed_color);
 175                                 *src = 'X'; _gen_pattern(table, pat, src, srclen, fixed_color);
 176                                 *src = 'O'; _gen_pattern(table, pat, src, srclen, fixed_color);
 177                                 *src = '#'; _gen_pattern(table, pat, src, srclen, fixed_color);
 178                                 *src = '?'; // for future recursions
 179                                 return;
 180                         case 'x':
 181                                 *src = '.'; _gen_pattern(table, pat, src, srclen, fixed_color);
 182                                 *src = 'O'; _gen_pattern(table, pat, src, srclen, fixed_color);
 183                                 *src = '#'; _gen_pattern(table, pat, src, srclen, fixed_color);
 184                                 *src = 'x'; // for future recursions
 185                                 return;
 186                         case 'o':
 187                                 *src = '.'; _gen_pattern(table, pat, src, srclen, fixed_color);
 188                                 *src = 'X'; _gen_pattern(table, pat, src, srclen, fixed_color);
 189                                 *src = '#'; _gen_pattern(table, pat, src, srclen, fixed_color);
 190                                 *src = 'o'; // for future recursions
 191                                 return;
 192                         case '.': /* 0 */ break;
 193                         case 'X': pat |= S_BLACK << (patofs * 2); break;
 194                         case 'O': pat |= S_WHITE << (patofs * 2); break;
 195                         case '#': pat |= S_OFFBOARD << (patofs * 2); break;
 196                 }
 197         }
 198
 199         /* Original pattern, all transpositions and rotations */
 200         _record_pattern(table, src - 9, pat, fixed_color);
 201         _record_pattern(table, src - 9, _pat_vmirror(pat), fixed_color);
 202         _record_pattern(table, src - 9, _pat_hmirror(pat), fixed_color);
 203         _record_pattern(table, src - 9, _pat_vmirror(_pat_hmirror(pat)), fixed_color);
 204         _record_pattern(table, src - 9, _pat_90rot(pat), fixed_color);
 205         _record_pattern(table, src - 9, _pat_90rot(_pat_vmirror(pat)), fixed_color);
 206         _record_pattern(table, src - 9, _pat_90rot(_pat_hmirror(pat)), fixed_color);
 207         _record_pattern(table, src - 9, _pat_90rot(_pat_vmirror(_pat_hmirror(pat))), fixed_color);
 208 }
 209
 210 static void __attribute__((constructor))
 211 _init_patterns(void)
 212 {
 213         for (int i = 0; i < moggy_patterns_src_n; i++) {
 214                 int fixed_color = 0;
 215                 switch (moggy_patterns_src[i][9]) {
 216                         case 'X': fixed_color = S_BLACK; break;
 217                         case 'O': fixed_color = S_WHITE; break;
 218                 }
 219                 //fprintf(stderr, "** %s **\n", moggy_patterns_src[i]);
 220                 _gen_pattern(moggy_patterns, 0, moggy_patterns_src[i], 9, fixed_color);
 221         }
 222 }
 223
 224
 225 /* Check if we match any pattern centered on given move. */
 226 static bool
 227 test_pattern_here(struct playout_policy *p, char *hashtable,
 228                 struct board *b, struct move *m)
 229 {
 230         int pat = 0;
 231         int x = coord_x(m->coord, b), y = coord_y(m->coord, b);
 232         pat |= (board_atxy(b, x - 1, y - 1) << 14)
 233                 | (board_atxy(b, x, y - 1) << 12)
 234                 | (board_atxy(b, x + 1, y - 1) << 10);
 235         pat |= (board_atxy(b, x - 1, y) << 8)
 236                 | (board_atxy(b, x + 1, y) << 6);
 237         pat |= (board_atxy(b, x - 1, y + 1) << 4)
 238                 | (board_atxy(b, x, y + 1) << 2)
 239                 | (board_atxy(b, x + 1, y + 1));
 240         //fprintf(stderr, "(%d,%d) hashtable[%04x] = %d\n", x, y, pat, hashtable[pat]);
 241         return (hashtable[pat] & m->color) && !is_selfatari(b, m->color, m->coord);
 242 }
 243
 244 static void
 245 apply_pattern_here(struct playout_policy *p, char *hashtable,
 246                 struct board *b, struct move *m, struct move_queue *q)
 247 {
 248         if (test_pattern_here(p, hashtable, b, m))
 249                 q->move[q->moves++] = m->coord;
 250 }
 251
 252 /* Check if we match any pattern around given move (with the other color to play). */
 253 static coord_t
 254 apply_pattern(struct playout_policy *p, struct board *b, struct move *m)
 255 {
 256         //struct moggy_policy *pp = p->data;
 257         struct move_queue q;
 258         q.moves = 0;
 259
 260         /* Suicides do not make any patterns and confuse us. */
 261         if (board_at(b, m->coord) == S_NONE || board_at(b, m->coord) == S_OFFBOARD)
 262                 return pass;
 263
 264         foreach_neighbor(b, m->coord, {
 265                 struct move m2; m2.coord = c; m2.color = stone_other(m->color);
 266                 if (board_at(b, c) == S_NONE)
 267                         apply_pattern_here(p, moggy_patterns, b, &m2, &q);
 268         });
 269         foreach_diag_neighbor(b, m->coord) {
 270                 struct move m2; m2.coord = c; m2.color = stone_other(m->color);
 271                 if (board_at(b, c) == S_NONE)
 272                         apply_pattern_here(p, moggy_patterns, b, &m2, &q);
 273         } foreach_diag_neighbor_end;
 274
 275         if (PLDEBUGL(5)) {
 276                 fprintf(stderr, "Pattern candidate moves: ");
 277                 for (int i = 0; i < q.moves; i++) {
 278                         fprintf(stderr, "%s ", coord2sstr(q.move[i], b));
 279                 }
 280                 fprintf(stderr, "\n");
 281         }
 282
 283         int i = fast_random(q.moves);
 284         return q.moves ? q.move[i] : pass;
 285 }
 286
 287
 288
 289 /* Is this ladder breaker friendly for the one who catches ladder. */
 290 static bool
 291 ladder_catcher(struct board *b, int x, int y, enum stone laddered)
 292 {
 293         enum stone breaker = board_atxy(b, x, y);
 294         return breaker == stone_other(laddered) || breaker == S_OFFBOARD;
 295 }
 296
 297 static bool
 298 ladder_catches(struct playout_policy *p, struct board *b, coord_t coord, group_t laddered)
 299 {
 300         struct moggy_policy *pp = p->data;
 301
 302         /* This is very trivial and gets a lot of corner cases wrong.
 303          * We need this to be just very fast. One important point is
 304          * that we sometimes might not notice a ladder but if we do,
 305          * it should always work; thus we can use this for strong
 306          * negative hinting safely. */
 307         //fprintf(stderr, "ladder check\n");
 308
 309         enum stone lcolor = board_at(b, group_base(laddered));
 310         int x = coord_x(coord, b), y = coord_y(coord, b);
 311
 312         /* First, special-case first-line "ladders". This is a huge chunk
 313          * of ladders we actually meet and want to play. */
 314         if (pp->borderladders
 315             && neighbor_count_at(b, coord, S_OFFBOARD) == 1
 316             && neighbor_count_at(b, coord, lcolor) == 1) {
 317                 if (PLDEBUGL(5))
 318                         fprintf(stderr, "border ladder\n");
 319                 /* Direction along border; xd is horiz. border, yd vertical. */
 320                 int xd = 0, yd = 0;
 321                 if (board_atxy(b, x + 1, y) == S_OFFBOARD || board_atxy(b, x - 1, y) == S_OFFBOARD)
 322                         yd = 1;
 323                 else
 324                         xd = 1;
 325                 /* Direction from the border; -1 is above/left, 1 is below/right. */
 326                 int dd = (board_atxy(b, x + yd, y + xd) == S_OFFBOARD) ? 1 : -1;
 327                 if (PLDEBUGL(6))
 328                         fprintf(stderr, "xd %d yd %d dd %d\n", xd, yd, dd);
 329                 /* | ? ?
 330                  * | . O #
 331                  * | c X #
 332                  * | . O #
 333                  * | ? ?   */
 334                 /* This is normally caught, unless we have friends both above
 335                  * and below... */
 336                 if (board_atxy(b, x + xd * 2, y + yd * 2) == lcolor
 337                     && board_atxy(b, x - xd * 2, y - yd * 2) == lcolor)
 338                         return false;
 339                 /* ...or can't block where we need because of shortage
 340                  * of liberties. */
 341                 int libs1 = board_group_info(b, group_atxy(b, x + xd - yd * dd, y + yd - xd * dd)).libs;
 342                 int libs2 = board_group_info(b, group_atxy(b, x - xd - yd * dd, y - yd - xd * dd)).libs;
 343                 if (PLDEBUGL(6))
 344                         fprintf(stderr, "libs1 %d libs2 %d\n", libs1, libs2);
 345                 if (libs1 < 2 && libs2 < 2)
 346                         return false;
 347                 if (board_atxy(b, x + xd * 2, y + yd * 2) == lcolor && libs1 < 3)
 348                         return false;
 349                 if (board_atxy(b, x - xd * 2, y - yd * 2) == lcolor && libs2 < 3)
 350                         return false;
 351                 return true;
 352         }
 353
 354         /* Figure out the ladder direction */
 355         int xd, yd;
 356         xd = board_atxy(b, x + 1, y) == S_NONE ? 1 : board_atxy(b, x - 1, y) == S_NONE ? -1 : 0;
 357         yd = board_atxy(b, x, y + 1) == S_NONE ? 1 : board_atxy(b, x, y - 1) == S_NONE ? -1 : 0;
 358
 359         /* We do only tight ladders, not loose ladders. Furthermore,
 360          * the ladders need to be simple:
 361          * . X .             . . X
 362          * c O X supported   . c O unsupported
 363          * X # #             X O #
 364          */
 365
 366         /* For given (xd,yd), we have two possibilities where to move
 367          * next. Consider (-1,1):
 368          * n X .   n c X
 369          * c O X   X O #
 370          * X # #   . X #
 371          */
 372         if (!xd || !yd || !(ladder_catcher(b, x - xd, y, lcolor) ^ ladder_catcher(b, x, y - yd, lcolor))) {
 373                 /* Silly situation, probably non-simple ladder or suicide. */
 374                 /* TODO: In case of basic non-simple ladder, play out both variants. */
 375                 if (PLDEBUGL(5))
 376                         fprintf(stderr, "non-simple ladder\n");
 377                 return false;
 378         }
 379
 380 #define ladder_check(xd1_, yd1_, xd2_, yd2_)    \
 381         if (board_atxy(b, x, y) != S_NONE) { \
 382                 /* Did we hit a stone when playing out ladder? */ \
 383                 if (ladder_catcher(b, x, y, lcolor)) \
 384                         return true; /* ladder works */ \
 385                 if (board_group_info(b, group_atxy(b, x, y)).lib[0] > 0) \
 386                         return false; /* friend that's not in atari himself */ \
 387         } else { \
 388                 /* No. So we are at new position. \
 389                  * We need to check indirect ladder breakers. */ \
 390                 /* . 2 x . . \
 391                  * . x o O 1 <- only at O we can check for o at 2 \
 392                  * x o o x .    otherwise x at O would be still deadly \
 393                  * o o x . . \
 394                  * We check for o and x at 1, these are vital. \
 395                  * We check only for o at 2; x at 2 would mean we \
 396                  * need to fork (one step earlier). */ \
 397                 enum stone s1 = board_atxy(b, x + (xd1_), y + (yd1_)); \
 398                 if (s1 == lcolor) return false; \
 399                 if (s1 == stone_other(lcolor)) return true; \
 400                 enum stone s2 = board_atxy(b, x + (xd2_), y + (yd2_)); \
 401                 if (s2 == lcolor) return false; \
 402         }
 403 #define ladder_horiz    do { if (PLDEBUGL(6)) fprintf(stderr, "%d,%d horiz step %d\n", x, y, xd); x += xd; ladder_check(xd, 0, -2 * xd, yd); } while (0)
 404 #define ladder_vert     do { if (PLDEBUGL(6)) fprintf(stderr, "%d,%d vert step %d\n", x, y, yd); y += yd; ladder_check(0, yd, xd, -2 * yd); } while (0)
 405
 406         if (ladder_catcher(b, x - xd, y, lcolor))
 407                 ladder_horiz;
 408         do {
 409                 ladder_vert;
 410                 ladder_horiz;
 411         } while (1);
 412 }
 413
 414
 415 static void
 416 group_atari_check(struct playout_policy *p, struct board *b, group_t group, struct move_queue *q)
 417 {
 418         struct moggy_policy *pp = p->data;
 419
 420         /* Do not bother with kos. */
 421         if (group_is_onestone(b, group))
 422                 return;
 423
 424         enum stone color = board_at(b, group_base(group));
 425         coord_t lib = board_group_info(b, group).lib[0];
 426
 427         assert(color != S_OFFBOARD && color != S_NONE);
 428         if (PLDEBUGL(5))
 429                 fprintf(stderr, "atariiiiiiiii %s of color %d\n", coord2sstr(lib, b), color);
 430         assert(board_at(b, lib) == S_NONE);
 431
 432         /* Can we capture some neighbor? */
 433         foreach_in_group(b, group) {
 434                 foreach_neighbor(b, c, {
 435                         if (board_at(b, c) != stone_other(color)
 436                             || board_group_info(b, group_at(b, c)).libs > 1)
 437                                 continue;
 438                         if (PLDEBUGL(6))
 439                                 fprintf(stderr, "can capture group %d\n", group_at(b, c));
 440                         /* If we are saving our group, capture! */
 441                         if (b->last_move.color == stone_other(color))
 442                                 q->move[q->moves++] = board_group_info(b, group_at(b, c)).lib[0];
 443                         else /* If we chase the group, capture it now! */
 444                                 q->move[q->moves++] = lib;
 445                         /* Make sure capturing the group will actually
 446                          * expand our liberties if we are filling our
 447                          * last liberty. */
 448                         if (q->move[q->moves - 1] == lib && is_selfatari(b, color, lib))
 449                                 q->moves--;
 450                         else
 451                                 mq_nodup(q);
 452                 });
 453         } foreach_in_group_end;
 454
 455         /* Do not suicide... */
 456         if (is_selfatari(b, color, lib))
 457                 return;
 458         if (PLDEBUGL(6))
 459                 fprintf(stderr, "...escape route valid\n");
 460
 461         /* ...or play out ladders. */
 462         if (pp->ladders && ladder_catches(p, b, lib, group)) {
 463                 return;
 464         }
 465         if (PLDEBUGL(6))
 466                 fprintf(stderr, "...no ladder\n");
 467
 468         q->move[q->moves++] = lib;
 469         mq_nodup(q);
 470 }
 471
 472 static coord_t
 473 global_atari_check(struct playout_policy *p, struct board *b)
 474 {
 475         struct move_queue q;
 476         q.moves = 0;
 477
 478         if (b->clen == 0)
 479                 return pass;
 480
 481         int g_base = fast_random(b->clen);
 482         for (int g = g_base; g < b->clen; g++) {
 483                 group_atari_check(p, b, group_at(b, group_base(b->c[g])), &q);
 484                 if (q.moves > 0)
 485                         return q.move[fast_random(q.moves)];
 486         }
 487         for (int g = 0; g < g_base; g++) {
 488                 group_atari_check(p, b, group_at(b, group_base(b->c[g])), &q);
 489                 if (q.moves > 0)
 490                         return q.move[fast_random(q.moves)];
 491         }
 492         return pass;
 493 }
 494
 495 static coord_t
 496 local_atari_check(struct playout_policy *p, struct board *b, struct move *m)
 497 {
 498         struct move_queue q;
 499         q.moves = 0;
 500
 501         /* Did the opponent play a self-atari? */
 502         if (board_group_info(b, group_at(b, m->coord)).libs == 1) {
 503                 group_atari_check(p, b, group_at(b, m->coord), &q);
 504         }
 505
 506         foreach_neighbor(b, m->coord, {
 507                 group_t g = group_at(b, c);
 508                 if (!g || board_group_info(b, g).libs != 1)
 509                         continue;
 510                 group_atari_check(p, b, g, &q);
 511         });
 512
 513         if (PLDEBUGL(5)) {
 514                 fprintf(stderr, "Local atari candidate moves: ");
 515                 for (int i = 0; i < q.moves; i++) {
 516                         fprintf(stderr, "%s ", coord2sstr(q.move[i], b));
 517                 }
 518                 fprintf(stderr, "\n");
 519         }
 520
 521         int i = fast_random(q.moves);
 522         return q.moves ? q.move[i] : pass;
 523 }
 524
 525 coord_t
 526 playout_moggy_choose(struct playout_policy *p, struct board *b, enum stone to_play)
 527 {
 528         struct moggy_policy *pp = p->data;
 529         coord_t c;
 530
 531         if (PLDEBUGL(5))
 532                 board_print(b, stderr);
 533
 534         /* Local checks */
 535         if (!is_pass(b->last_move.coord)) {
 536                 /* Local group in atari? */
 537                 if (pp->lcapturerate > fast_random(100)) {
 538                         c = local_atari_check(p, b, &b->last_move);
 539                         if (!is_pass(c))
 540                                 return c;
 541                 }
 542
 543                 /* Check for patterns we know */
 544                 if (pp->patternrate > fast_random(100)) {
 545                         c = apply_pattern(p, b, &b->last_move);
 546                         if (!is_pass(c))
 547                                 return c;
 548                 }
 549         }
 550
 551         /* Global checks */
 552
 553         /* Any groups in atari? */
 554         if (pp->capturerate > fast_random(100)) {
 555                 c = global_atari_check(p, b);
 556                 if (!is_pass(c))
 557                         return c;
 558         }
 559
 560         return pass;
 561 }
 562
 563 float
 564 playout_moggy_assess(struct playout_policy *p, struct board *b, struct move *m)
 565 {
 566         struct moggy_policy *pp = p->data;
 567
 568         if (is_pass(m->coord))
 569                 return NAN;
 570
 571         if (PLDEBUGL(5)) {
 572                 fprintf(stderr, "ASSESS of %s:\n", coord2sstr(m->coord, b));
 573                 board_print(b, stderr);
 574         }
 575
 576         /* Are we dealing with atari? */
 577         if (pp->lcapturerate || pp->capturerate) {
 578                 bool ladder = false;
 579
 580                 foreach_neighbor(b, m->coord, {
 581                         group_t g = group_at(b, c);
 582                         if (!g || board_group_info(b, g).libs != 1)
 583                                 continue;
 584
 585                         struct move_queue q; q.moves = 0;
 586                         group_atari_check(p, b, g, &q);
 587                         while (q.moves--)
 588                                 if (q.move[q.moves] == m->coord) {
 589                                         if (PLDEBUGL(5))
 590                                                 fprintf(stderr, "1.0: atari\n");
 591                                         return 1.0;
 592                                 }
 593
 594                         /* _Never_ play here if this move plays out
 595                          * a caught ladder. (Unless it captures another
 596                          * group. :-) */
 597                         if (pp->ladderassess && ladder_catches(p, b, m->coord, g)) {
 598                                 /* Note that the opposite is not guarded against;
 599                                  * we do not advise against capturing a laddered
 600                                  * group (but we don't encourage it either). Such
 601                                  * a move can simplify tactical situations if we
 602                                  * can afford it. */
 603                                 if (m->color == board_at(b, c))
 604                                         ladder = true;
 605                         }
 606                 });
 607
 608                 if (ladder) {
 609                         if (PLDEBUGL(5))
 610                                 fprintf(stderr, "0.0: ladder\n");
 611                         return 0.0;
 612                 }
 613         }
 614
 615         /* Pattern check */
 616         if (pp->patternrate) {
 617                 if (test_pattern_here(p, moggy_patterns, b, m)) {
 618                         if (PLDEBUGL(5))
 619                                 fprintf(stderr, "1.0: pattern\n");
 620                         return 1.0;
 621                 }
 622         }
 623
 624         return NAN;
 625 }
 626
 627 bool
 628 playout_moggy_permit(struct playout_policy *p, struct board *b, struct move *m)
 629 {
 630         struct moggy_policy *pp = p->data;
 631
 632         /* The idea is simple for now - never allow self-atari moves.
 633          * They suck in general, but this also permits us to actually
 634          * handle seki in the playout stage. */
 635         /* FIXME: We must allow self-atari in some basic nakade shapes. */
 636 #if 0
 637         if (is_selfatari(b, m->color, m->coord))
 638                 fprintf(stderr, "__ Prohibiting self-atari %s %s\n", stone2str(m->color), coord2sstr(m->coord, b));
 639 #endif
 640         return fast_random(100) >= pp->selfatarirate || !is_selfatari(b, m->color, m->coord);
 641 }
 642
 643
 644 struct playout_policy *
 645 playout_moggy_init(char *arg)
 646 {
 647         struct playout_policy *p = calloc(1, sizeof(*p));
 648         struct moggy_policy *pp = calloc(1, sizeof(*pp));
 649         p->data = pp;
 650         p->choose = playout_moggy_choose;
 651         p->assess = playout_moggy_assess;
 652         p->permit = playout_moggy_permit;
 653
 654         pp->lcapturerate = 90;
 655         pp->capturerate = 90;
 656         pp->patternrate = 90;
 657         pp->selfatarirate = 90;
 658         pp->ladders = pp->borderladders = true;
 659         pp->ladderassess = true;
 660
 661         if (arg) {
 662                 char *optspec, *next = arg;
 663                 while (*next) {
 664                         optspec = next;
 665                         next += strcspn(next, ":");
 666                         if (*next) { *next++ = 0; } else { *next = 0; }
 667
 668                         char *optname = optspec;
 669                         char *optval = strchr(optspec, '=');
 670                         if (optval) *optval++ = 0;
 671
 672                         if (!strcasecmp(optname, "lcapturerate") && optval) {
 673                                 pp->lcapturerate = atoi(optval);
 674                         } else if (!strcasecmp(optname, "capturerate") && optval) {
 675                                 pp->capturerate = atoi(optval);
 676                         } else if (!strcasecmp(optname, "patternrate") && optval) {
 677                                 pp->patternrate = atoi(optval);
 678                         } else if (!strcasecmp(optname, "selfatarirate") && optval) {
 679                                 pp->selfatarirate = atoi(optval);
 680                         } else if (!strcasecmp(optname, "ladders")) {
 681                                 pp->ladders = optval && *optval == '0' ? false : true;
 682                         } else if (!strcasecmp(optname, "borderladders")) {
 683                                 pp->borderladders = optval && *optval == '0' ? false : true;
 684                         } else if (!strcasecmp(optname, "ladderassess")) {
 685                                 pp->ladderassess = optval && *optval == '0' ? false : true;
 686                         } else {
 687                                 fprintf(stderr, "playout-moggy: Invalid policy argument %s or missing value\n", optname);
 688                         }
 689                 }
 690         }
 691
 692         return p;
 693 }