15 #include "joseki/base.h"
17 #include "playout/moggy.h"
18 #include "playout/light.h"
19 #include "tactics/util.h"
21 #include "uct/dynkomi.h"
22 #include "uct/internal.h"
23 #include "uct/plugins.h"
24 #include "uct/prior.h"
25 #include "uct/search.h"
26 #include "uct/slave.h"
31 struct uct_policy
*policy_ucb1_init(struct uct
*u
, char *arg
);
32 struct uct_policy
*policy_ucb1amaf_init(struct uct
*u
, char *arg
);
33 static void uct_pondering_start(struct uct
*u
, struct board
*b0
, struct tree
*t
, enum stone color
);
35 /* Maximal simulation length. */
36 #define MC_GAMELEN MAX_GAMELEN
40 setup_state(struct uct
*u
, struct board
*b
, enum stone color
)
42 u
->t
= tree_init(b
, color
, u
->fast_alloc
? u
->max_tree_size
: 0,
43 u
->max_pruned_size
, u
->pruning_threshold
, u
->local_tree_aging
, u
->stats_hbits
);
45 fast_srandom(u
->force_seed
);
47 fprintf(stderr
, "Fresh board with random seed %lu\n", fast_getseed());
48 //board_print(b, stderr);
49 if (!u
->no_tbook
&& b
->moves
== 0) {
50 assert(color
== S_BLACK
);
56 reset_state(struct uct
*u
)
59 tree_done(u
->t
); u
->t
= NULL
;
63 setup_dynkomi(struct uct
*u
, struct board
*b
, enum stone to_play
)
65 if (u
->t
->use_extra_komi
&& !u
->pondering
&& u
->dynkomi
->permove
)
66 u
->t
->extra_komi
= u
->dynkomi
->permove(u
->dynkomi
, b
, u
->t
);
67 else if (!u
->t
->use_extra_komi
)
72 uct_prepare_move(struct uct
*u
, struct board
*b
, enum stone color
)
75 /* Verify that we have sane state. */
77 assert(u
->t
&& b
->moves
);
78 if (color
!= stone_other(u
->t
->root_color
)) {
79 fprintf(stderr
, "Fatal: Non-alternating play detected %d %d\n",
80 color
, u
->t
->root_color
);
83 uct_htable_reset(u
->t
);
86 /* We need fresh state. */
88 setup_state(u
, b
, color
);
91 u
->ownermap
.playouts
= 0;
92 memset(u
->ownermap
.map
, 0, board_size2(b
) * sizeof(u
->ownermap
.map
[0]));
93 u
->played_own
= u
->played_all
= 0;
97 dead_group_list(struct uct
*u
, struct board
*b
, struct move_queue
*mq
)
99 struct group_judgement gj
;
101 gj
.gs
= alloca(board_size2(b
) * sizeof(gj
.gs
[0]));
102 board_ownermap_judge_group(b
, &u
->ownermap
, &gj
);
103 groups_of_status(b
, &gj
, GS_DEAD
, mq
);
107 uct_pass_is_safe(struct uct
*u
, struct board
*b
, enum stone color
, bool pass_all_alive
)
109 if (u
->ownermap
.playouts
< GJ_MINGAMES
)
112 struct move_queue mq
= { .moves
= 0 };
113 dead_group_list(u
, b
, &mq
);
114 if (pass_all_alive
&& mq
.moves
> 0)
115 return false; // We need to remove some dead groups first.
116 return pass_is_safe(b
, color
, &mq
);
120 uct_printhook_ownermap(struct board
*board
, coord_t c
, char *s
, char *end
)
122 struct uct
*u
= board
->es
;
127 const char chr
[] = ":XO,"; // dame, black, white, unclear
128 const char chm
[] = ":xo,";
129 char ch
= chr
[board_ownermap_judge_point(&u
->ownermap
, c
, GJ_THRES
)];
130 if (ch
== ',') { // less precise estimate then?
131 ch
= chm
[board_ownermap_judge_point(&u
->ownermap
, c
, 0.67)];
133 s
+= snprintf(s
, end
- s
, "%c ", ch
);
138 uct_notify_play(struct engine
*e
, struct board
*b
, struct move
*m
)
140 struct uct
*u
= e
->data
;
142 /* No state, create one - this is probably game beginning
143 * and we need to load the opening tbook right now. */
144 uct_prepare_move(u
, b
, m
->color
);
148 /* Stop pondering, required by tree_promote_at() */
149 uct_pondering_stop(u
);
150 if (UDEBUGL(2) && u
->slave
)
151 tree_dump(u
->t
, u
->dumpthres
);
153 if (is_resign(m
->coord
)) {
159 /* Promote node of the appropriate move to the tree root. */
161 if (!tree_promote_at(u
->t
, b
, m
->coord
)) {
163 fprintf(stderr
, "Warning: Cannot promote move node! Several play commands in row?\n");
168 /* If we are a slave in a distributed engine, start pondering once
169 * we know which move we actually played. See uct_genmove() about
170 * the check for pass. */
171 if (u
->pondering_opt
&& u
->slave
&& m
->color
== u
->my_color
&& !is_pass(m
->coord
))
172 uct_pondering_start(u
, b
, u
->t
, stone_other(m
->color
));
178 uct_undo(struct engine
*e
, struct board
*b
)
180 struct uct
*u
= e
->data
;
182 if (!u
->t
) return NULL
;
183 uct_pondering_stop(u
);
189 uct_result(struct engine
*e
, struct board
*b
)
191 struct uct
*u
= e
->data
;
192 static char reply
[1024];
196 enum stone color
= u
->t
->root_color
;
197 struct tree_node
*n
= u
->t
->root
;
198 snprintf(reply
, 1024, "%s %s %d %.2f %.1f",
199 stone2str(color
), coord2sstr(n
->coord
, b
),
200 n
->u
.playouts
, tree_node_get_value(u
->t
, -1, n
->u
.value
),
201 u
->t
->use_extra_komi
? u
->t
->extra_komi
: 0);
206 uct_chat(struct engine
*e
, struct board
*b
, char *cmd
)
208 struct uct
*u
= e
->data
;
209 static char reply
[1024];
211 cmd
+= strspn(cmd
, " \n\t");
212 if (!strncasecmp(cmd
, "winrate", 7)) {
214 return "no game context (yet?)";
215 enum stone color
= u
->t
->root_color
;
216 struct tree_node
*n
= u
->t
->root
;
217 snprintf(reply
, 1024, "In %d playouts at %d threads, %s %s can win with %.2f%% probability",
218 n
->u
.playouts
, u
->threads
, stone2str(color
), coord2sstr(n
->coord
, b
),
219 tree_node_get_value(u
->t
, -1, n
->u
.value
) * 100);
220 if (u
->t
->use_extra_komi
&& abs(u
->t
->extra_komi
) >= 0.5) {
221 sprintf(reply
+ strlen(reply
), ", while self-imposing extra komi %.1f",
231 uct_dead_group_list(struct engine
*e
, struct board
*b
, struct move_queue
*mq
)
233 struct uct
*u
= e
->data
;
235 /* This means the game is probably over, no use pondering on. */
236 uct_pondering_stop(u
);
238 if (u
->pass_all_alive
)
239 return; // no dead groups
241 bool mock_state
= false;
244 /* No state, but we cannot just back out - we might
245 * have passed earlier, only assuming some stones are
246 * dead, and then re-connected, only to lose counting
247 * when all stones are assumed alive. */
248 uct_prepare_move(u
, b
, S_BLACK
); assert(u
->t
);
251 /* Make sure the ownermap is well-seeded. */
252 while (u
->ownermap
.playouts
< GJ_MINGAMES
)
253 uct_playout(u
, b
, S_BLACK
, u
->t
);
254 /* Show the ownermap: */
256 board_print_custom(b
, stderr
, uct_printhook_ownermap
);
258 dead_group_list(u
, b
, mq
);
261 /* Clean up the mock state in case we will receive
262 * a genmove; we could get a non-alternating-move
263 * error from uct_prepare_move() in that case otherwise. */
269 playout_policy_done(struct playout_policy
*p
)
271 if (p
->done
) p
->done(p
);
272 if (p
->data
) free(p
->data
);
277 uct_done(struct engine
*e
)
279 /* This is called on engine reset, especially when clear_board
280 * is received and new game should begin. */
281 struct uct
*u
= e
->data
;
282 uct_pondering_stop(u
);
283 if (u
->t
) reset_state(u
);
284 free(u
->ownermap
.map
);
287 free(u
->random_policy
);
288 playout_policy_done(u
->playout
);
289 uct_prior_done(u
->prior
);
290 joseki_done(u
->jdict
);
291 pluginset_done(u
->plugins
);
296 /* Run time-limited MCTS search on foreground. */
298 uct_search(struct uct
*u
, struct board
*b
, struct time_info
*ti
, enum stone color
, struct tree
*t
)
300 struct uct_search_state s
;
301 uct_search_start(u
, b
, color
, t
, ti
, &s
);
302 if (UDEBUGL(2) && s
.base_playouts
> 0)
303 fprintf(stderr
, "<pre-simulated %d games>\n", s
.base_playouts
);
305 /* The search tree is ctx->t. This is currently == . It is important
306 * to reference ctx->t directly since the
307 * thread manager will swap the tree pointer asynchronously. */
309 /* Now, just periodically poll the search tree. */
310 /* Note that in case of TD_GAMES, threads will terminate independently
311 * of the uct_search_check_stop() signalization. */
313 time_sleep(TREE_BUSYWAIT_INTERVAL
);
314 /* TREE_BUSYWAIT_INTERVAL should never be less than desired time, or the
315 * time control is broken. But if it happens to be less, we still search
316 * at least 100ms otherwise the move is completely random. */
318 int i
= uct_search_games(&s
);
319 /* Print notifications etc. */
320 uct_search_progress(u
, b
, color
, t
, ti
, &s
, i
);
321 /* Check if we should stop the search. */
322 if (uct_search_check_stop(u
, b
, color
, t
, ti
, &s
, i
))
326 struct uct_thread_ctx
*ctx
= uct_search_stop();
327 if (UDEBUGL(2)) tree_dump(t
, u
->dumpthres
);
329 fprintf(stderr
, "(avg score %f/%d value %f/%d)\n",
330 u
->dynkomi
->score
.value
, u
->dynkomi
->score
.playouts
,
331 u
->dynkomi
->value
.value
, u
->dynkomi
->value
.playouts
);
333 uct_progress_status(u
, t
, color
, ctx
->games
);
335 u
->played_own
+= ctx
->games
;
339 /* Start pondering background with @color to play. */
341 uct_pondering_start(struct uct
*u
, struct board
*b0
, struct tree
*t
, enum stone color
)
344 fprintf(stderr
, "Starting to ponder with color %s\n", stone2str(stone_other(color
)));
347 /* We need a local board copy to ponder upon. */
348 struct board
*b
= malloc2(sizeof(*b
)); board_copy(b
, b0
);
350 /* *b0 did not have the genmove'd move played yet. */
351 struct move m
= { t
->root
->coord
, t
->root_color
};
352 int res
= board_play(b
, &m
);
354 setup_dynkomi(u
, b
, stone_other(m
.color
));
356 /* Start MCTS manager thread "headless". */
357 static struct uct_search_state s
;
358 uct_search_start(u
, b
, color
, t
, NULL
, &s
);
361 /* uct_search_stop() frontend for the pondering (non-genmove) mode, and
362 * to stop the background search for a slave in the distributed engine. */
364 uct_pondering_stop(struct uct
*u
)
366 if (!thread_manager_running
)
369 /* Stop the thread manager. */
370 struct uct_thread_ctx
*ctx
= uct_search_stop();
372 if (u
->pondering
) fprintf(stderr
, "(pondering) ");
373 uct_progress_status(u
, ctx
->t
, ctx
->color
, ctx
->games
);
377 u
->pondering
= false;
383 uct_genmove_setup(struct uct
*u
, struct board
*b
, enum stone color
)
385 if (b
->superko_violation
) {
386 fprintf(stderr
, "!!! WARNING: SUPERKO VIOLATION OCCURED BEFORE THIS MOVE\n");
387 fprintf(stderr
, "Maybe you play with situational instead of positional superko?\n");
388 fprintf(stderr
, "I'm going to ignore the violation, but note that I may miss\n");
389 fprintf(stderr
, "some moves valid under this ruleset because of this.\n");
390 b
->superko_violation
= false;
393 uct_prepare_move(u
, b
, color
);
398 /* How to decide whether to use dynkomi in this game? Since we use
399 * pondering, it's not simple "who-to-play" matter. Decide based on
400 * the last genmove issued. */
401 u
->t
->use_extra_komi
= !!(u
->dynkomi_mask
& color
);
402 /* Moreover, we do not use extra komi at the game end - we are not
403 * to fool ourselves at this point. */
404 if (board_estimated_moves_left(b
) <= MIN_MOVES_LEFT
)
405 u
->t
->use_extra_komi
= false;
406 setup_dynkomi(u
, b
, color
);
408 if (b
->rules
== RULES_JAPANESE
)
409 u
->territory_scoring
= true;
411 /* Make pessimistic assumption about komi for Japanese rules to
412 * avoid losing by 0.5 when winning by 0.5 with Chinese rules.
413 * The rules usually give the same winner if the integer part of komi
414 * is odd so we adjust the komi only if it is even (for a board of
415 * odd size). We are not trying to get an exact evaluation for rare
416 * cases of seki. For details see http://home.snafu.de/jasiek/parity.html */
417 if (u
->territory_scoring
&& (((int)floor(b
->komi
) + board_size(b
)) & 1)) {
418 b
->komi
+= (color
== S_BLACK
? 1.0 : -1.0);
420 fprintf(stderr
, "Setting komi to %.1f assuming Japanese rules\n",
426 uct_genmove(struct engine
*e
, struct board
*b
, struct time_info
*ti
, enum stone color
, bool pass_all_alive
)
428 double start_time
= time_now();
429 struct uct
*u
= e
->data
;
430 uct_pondering_stop(u
);
431 uct_genmove_setup(u
, b
, color
);
433 /* Start the Monte Carlo Tree Search! */
434 int base_playouts
= u
->t
->root
->u
.playouts
;
435 int played_games
= uct_search(u
, b
, ti
, color
, u
->t
);
438 struct tree_node
*best
;
439 best
= uct_search_result(u
, b
, color
, pass_all_alive
, played_games
, base_playouts
, &best_coord
);
442 double time
= time_now() - start_time
+ 0.000001; /* avoid divide by zero */
443 fprintf(stderr
, "genmove in %0.2fs (%d games/s, %d games/s/thread)\n",
444 time
, (int)(played_games
/time
), (int)(played_games
/time
/u
->threads
));
448 /* Pass or resign. */
450 return coord_copy(best_coord
);
452 tree_promote_node(u
->t
, &best
);
454 /* After a pass, pondering is harmful for two reasons:
455 * (i) We might keep pondering even when the game is over.
456 * Of course this is the case for opponent resign as well.
457 * (ii) More importantly, the ownermap will get skewed since
458 * the UCT will start cutting off any playouts. */
459 if (u
->pondering_opt
&& !is_pass(best
->coord
)) {
460 uct_pondering_start(u
, b
, u
->t
, stone_other(color
));
462 return coord_copy(best_coord
);
467 uct_gentbook(struct engine
*e
, struct board
*b
, struct time_info
*ti
, enum stone color
)
469 struct uct
*u
= e
->data
;
470 if (!u
->t
) uct_prepare_move(u
, b
, color
);
473 if (ti
->dim
== TD_GAMES
) {
474 /* Don't count in games that already went into the tbook. */
475 ti
->len
.games
+= u
->t
->root
->u
.playouts
;
477 uct_search(u
, b
, ti
, color
, u
->t
);
479 assert(ti
->dim
== TD_GAMES
);
480 tree_save(u
->t
, b
, ti
->len
.games
/ 100);
486 uct_dumptbook(struct engine
*e
, struct board
*b
, enum stone color
)
488 struct uct
*u
= e
->data
;
489 struct tree
*t
= tree_init(b
, color
, u
->fast_alloc
? u
->max_tree_size
: 0,
490 u
->max_pruned_size
, u
->pruning_threshold
, u
->local_tree_aging
, 0);
498 uct_evaluate(struct engine
*e
, struct board
*b
, struct time_info
*ti
, coord_t c
, enum stone color
)
500 struct uct
*u
= e
->data
;
504 struct move m
= { c
, color
};
505 int res
= board_play(&b2
, &m
);
508 color
= stone_other(color
);
510 if (u
->t
) reset_state(u
);
511 uct_prepare_move(u
, &b2
, color
);
515 uct_search(u
, &b2
, ti
, color
, u
->t
);
516 struct tree_node
*best
= u
->policy
->choose(u
->policy
, u
->t
->root
, &b2
, color
, resign
);
518 bestval
= NAN
; // the opponent has no reply!
520 bestval
= tree_node_get_value(u
->t
, 1, best
->u
.value
);
523 reset_state(u
); // clean our junk
525 return isnan(bestval
) ? NAN
: 1.0f
- bestval
;
530 uct_state_init(char *arg
, struct board
*b
)
532 struct uct
*u
= calloc2(1, sizeof(struct uct
));
534 u
->debug_level
= debug_level
;
535 u
->gamelen
= MC_GAMELEN
;
536 u
->resign_threshold
= 0.2;
537 u
->sure_win_threshold
= 0.85;
539 u
->significant_threshold
= 50;
542 u
->playout_amaf
= true;
543 u
->playout_amaf_nakade
= false;
544 u
->amaf_prior
= false;
545 u
->max_tree_size
= 3072ULL * 1048576;
546 u
->pruning_threshold
= 0;
549 u
->thread_model
= TM_TREEVL
;
552 u
->fuseki_end
= 20; // max time at 361*20% = 72 moves (our 36th move, still 99 to play)
553 u
->yose_start
= 40; // (100-40-25)*361/100/2 = 63 moves still to play by us then
554 u
->bestr_ratio
= 0.02;
555 // 2.5 is clearly too much, but seems to compensate well for overly stern time allocations.
556 // TODO: Further tuning and experiments with better time allocation schemes.
557 u
->best2_ratio
= 2.5;
558 u
->max_maintime_ratio
= 8.0;
560 u
->val_scale
= 0.04; u
->val_points
= 40;
561 u
->dynkomi_interval
= 1000;
562 u
->dynkomi_mask
= S_BLACK
| S_WHITE
;
565 u
->local_tree_aging
= 80;
566 u
->local_tree_allseq
= 1;
567 u
->local_tree_depth_decay
= 1.5;
569 u
->plugins
= pluginset_init(b
);
571 u
->jdict
= joseki_load(b
->size
);
574 char *optspec
, *next
= arg
;
577 next
+= strcspn(next
, ",");
578 if (*next
) { *next
++ = 0; } else { *next
= 0; }
580 char *optname
= optspec
;
581 char *optval
= strchr(optspec
, '=');
582 if (optval
) *optval
++ = 0;
586 if (!strcasecmp(optname
, "debug")) {
588 u
->debug_level
= atoi(optval
);
591 } else if (!strcasecmp(optname
, "dumpthres") && optval
) {
592 /* When dumping the UCT tree on output, include
593 * nodes with at least this many playouts.
594 * (This value is re-scaled "intelligently"
595 * in case of very large trees.) */
596 u
->dumpthres
= atoi(optval
);
597 } else if (!strcasecmp(optname
, "resign_threshold") && optval
) {
598 /* Resign when this ratio of games is lost
599 * after GJ_MINGAMES sample is taken. */
600 u
->resign_threshold
= atof(optval
);
601 } else if (!strcasecmp(optname
, "sure_win_threshold") && optval
) {
602 /* Stop reading when this ratio of games is won
603 * after PLAYOUT_EARLY_BREAK_MIN sample is
604 * taken. (Prevents stupid time losses,
605 * friendly to human opponents.) */
606 u
->sure_win_threshold
= atof(optval
);
607 } else if (!strcasecmp(optname
, "force_seed") && optval
) {
608 /* Set RNG seed at the tree setup. */
609 u
->force_seed
= atoi(optval
);
610 } else if (!strcasecmp(optname
, "no_tbook")) {
611 /* Disable UCT opening tbook. */
613 } else if (!strcasecmp(optname
, "pass_all_alive")) {
614 /* Whether to consider passing only after all
615 * dead groups were removed from the board;
616 * this is like all genmoves are in fact
617 * kgs-genmove_cleanup. */
618 u
->pass_all_alive
= !optval
|| atoi(optval
);
619 } else if (!strcasecmp(optname
, "territory_scoring")) {
620 /* Use territory scoring (default is area scoring).
621 * An explicit kgs-rules command overrides this. */
622 u
->territory_scoring
= !optval
|| atoi(optval
);
623 } else if (!strcasecmp(optname
, "banner") && optval
) {
624 /* Additional banner string. This must come as the
625 * last engine parameter. */
626 if (*next
) *--next
= ',';
627 u
->banner
= strdup(optval
);
629 } else if (!strcasecmp(optname
, "plugin") && optval
) {
630 /* Load an external plugin; filename goes before the colon,
631 * extra arguments after the colon. */
632 char *pluginarg
= strchr(optval
, ':');
635 plugin_load(u
->plugins
, optval
, pluginarg
);
637 /** UCT behavior and policies */
639 } else if ((!strcasecmp(optname
, "policy")
640 /* Node selection policy. ucb1amaf is the
641 * default policy implementing RAVE, while
642 * ucb1 is the simple exploration/exploitation
643 * policy. Policies can take further extra
645 || !strcasecmp(optname
, "random_policy")) && optval
) {
646 /* A policy to be used randomly with small
647 * chance instead of the default policy. */
648 char *policyarg
= strchr(optval
, ':');
649 struct uct_policy
**p
= !strcasecmp(optname
, "policy") ? &u
->policy
: &u
->random_policy
;
652 if (!strcasecmp(optval
, "ucb1")) {
653 *p
= policy_ucb1_init(u
, policyarg
);
654 } else if (!strcasecmp(optval
, "ucb1amaf")) {
655 *p
= policy_ucb1amaf_init(u
, policyarg
);
657 fprintf(stderr
, "UCT: Invalid tree policy %s\n", optval
);
660 } else if (!strcasecmp(optname
, "playout") && optval
) {
661 /* Random simulation (playout) policy.
662 * moggy is the default policy with large
663 * amount of domain-specific knowledge and
664 * heuristics. light is a simple uniformly
665 * random move selection policy. */
666 char *playoutarg
= strchr(optval
, ':');
669 if (!strcasecmp(optval
, "moggy")) {
670 u
->playout
= playout_moggy_init(playoutarg
, b
, u
->jdict
);
671 } else if (!strcasecmp(optval
, "light")) {
672 u
->playout
= playout_light_init(playoutarg
, b
);
674 fprintf(stderr
, "UCT: Invalid playout policy %s\n", optval
);
677 } else if (!strcasecmp(optname
, "prior") && optval
) {
678 /* Node priors policy. When expanding a node,
679 * it will seed node values heuristically
680 * (most importantly, based on playout policy
681 * opinion, but also with regard to other
682 * things). See uct/prior.c for details.
683 * Use prior=eqex=0 to disable priors. */
684 u
->prior
= uct_prior_init(optval
, b
);
685 } else if (!strcasecmp(optname
, "mercy") && optval
) {
686 /* Minimal difference of black/white captures
687 * to stop playout - "Mercy Rule". Speeds up
688 * hopeless playouts at the expense of some
690 u
->mercymin
= atoi(optval
);
691 } else if (!strcasecmp(optname
, "gamelen") && optval
) {
692 /* Maximum length of single simulation
694 u
->gamelen
= atoi(optval
);
695 } else if (!strcasecmp(optname
, "expand_p") && optval
) {
696 /* Expand UCT nodes after it has been
697 * visited this many times. */
698 u
->expand_p
= atoi(optval
);
699 } else if (!strcasecmp(optname
, "random_policy_chance") && optval
) {
700 /* If specified (N), with probability 1/N, random_policy policy
701 * descend is used instead of main policy descend; useful
702 * if specified policy (e.g. UCB1AMAF) can make unduly biased
703 * choices sometimes, you can fall back to e.g.
704 * random_policy=UCB1. */
705 u
->random_policy_chance
= atoi(optval
);
707 /** General AMAF behavior */
708 /* (Only relevant if the policy supports AMAF.
709 * More variables can be tuned as policy
712 } else if (!strcasecmp(optname
, "playout_amaf")) {
713 /* Whether to include random playout moves in
714 * AMAF as well. (Otherwise, only tree moves
715 * are included in AMAF. Of course makes sense
716 * only in connection with an AMAF policy.) */
717 /* with-without: 55.5% (+-4.1) */
718 if (optval
&& *optval
== '0')
719 u
->playout_amaf
= false;
721 u
->playout_amaf
= true;
722 } else if (!strcasecmp(optname
, "playout_amaf_nakade")) {
723 /* Whether to include nakade moves from playouts
724 * in the AMAF statistics; this tends to nullify
725 * the playout_amaf effect by adding too much
727 if (optval
&& *optval
== '0')
728 u
->playout_amaf_nakade
= false;
730 u
->playout_amaf_nakade
= true;
731 } else if (!strcasecmp(optname
, "playout_amaf_cutoff") && optval
) {
732 /* Keep only first N% of playout stage AMAF
734 u
->playout_amaf_cutoff
= atoi(optval
);
735 } else if (!strcasecmp(optname
, "amaf_prior") && optval
) {
736 /* In node policy, consider prior values
737 * part of the real result term or part
738 * of the AMAF term? */
739 u
->amaf_prior
= atoi(optval
);
741 /** Performance and memory management */
743 } else if (!strcasecmp(optname
, "threads") && optval
) {
744 /* By default, Pachi will run with only single
745 * tree search thread! */
746 u
->threads
= atoi(optval
);
747 } else if (!strcasecmp(optname
, "thread_model") && optval
) {
748 if (!strcasecmp(optval
, "tree")) {
749 /* Tree parallelization - all threads
750 * grind on the same tree. */
751 u
->thread_model
= TM_TREE
;
753 } else if (!strcasecmp(optval
, "treevl")) {
754 /* Tree parallelization, but also
755 * with virtual losses - this discou-
756 * rages most threads choosing the
757 * same tree branches to read. */
758 u
->thread_model
= TM_TREEVL
;
760 fprintf(stderr
, "UCT: Invalid thread model %s\n", optval
);
763 } else if (!strcasecmp(optname
, "virtual_loss")) {
764 /* Number of virtual losses added before evaluating a node. */
765 u
->virtual_loss
= !optval
|| atoi(optval
);
766 } else if (!strcasecmp(optname
, "pondering")) {
767 /* Keep searching even during opponent's turn. */
768 u
->pondering_opt
= !optval
|| atoi(optval
);
769 } else if (!strcasecmp(optname
, "max_tree_size") && optval
) {
770 /* Maximum amount of memory [MiB] consumed by the move tree.
771 * For fast_alloc it includes the temp tree used for pruning.
772 * Default is 3072 (3 GiB). */
773 u
->max_tree_size
= atol(optval
) * 1048576;
774 } else if (!strcasecmp(optname
, "fast_alloc")) {
775 u
->fast_alloc
= !optval
|| atoi(optval
);
776 } else if (!strcasecmp(optname
, "pruning_threshold") && optval
) {
777 /* Force pruning at beginning of a move if the tree consumes
778 * more than this [MiB]. Default is 10% of max_tree_size.
779 * Increase to reduce pruning time overhead if memory is plentiful.
780 * This option is meaningful only for fast_alloc. */
781 u
->pruning_threshold
= atol(optval
) * 1048576;
785 } else if (!strcasecmp(optname
, "best2_ratio") && optval
) {
786 /* If set, prolong simulating while
787 * first_best/second_best playouts ratio
788 * is less than best2_ratio. */
789 u
->best2_ratio
= atof(optval
);
790 } else if (!strcasecmp(optname
, "bestr_ratio") && optval
) {
791 /* If set, prolong simulating while
792 * best,best_best_child values delta
793 * is more than bestr_ratio. */
794 u
->bestr_ratio
= atof(optval
);
795 } else if (!strcasecmp(optname
, "max_maintime_ratio") && optval
) {
796 /* If set and while not in byoyomi, prolong simulating no more than
797 * max_maintime_ratio times the normal desired thinking time. */
798 u
->max_maintime_ratio
= atof(optval
);
799 } else if (!strcasecmp(optname
, "fuseki_end") && optval
) {
800 /* At the very beginning it's not worth thinking
801 * too long because the playout evaluations are
802 * very noisy. So gradually increase the thinking
803 * time up to maximum when fuseki_end percent
804 * of the board has been played.
805 * This only applies if we are not in byoyomi. */
806 u
->fuseki_end
= atoi(optval
);
807 } else if (!strcasecmp(optname
, "yose_start") && optval
) {
808 /* When yose_start percent of the board has been
809 * played, or if we are in byoyomi, stop spending
810 * more time and spread the remaining time
812 * Between fuseki_end and yose_start, we spend
813 * a constant proportion of the remaining time
814 * on each move. (yose_start should actually
815 * be much earlier than when real yose start,
816 * but "yose" is a good short name to convey
818 u
->yose_start
= atoi(optval
);
822 } else if (!strcasecmp(optname
, "dynkomi") && optval
) {
823 /* Dynamic komi approach; there are multiple
824 * ways to adjust komi dynamically throughout
825 * play. We currently support two: */
826 char *dynkomiarg
= strchr(optval
, ':');
829 if (!strcasecmp(optval
, "none")) {
830 u
->dynkomi
= uct_dynkomi_init_none(u
, dynkomiarg
, b
);
831 } else if (!strcasecmp(optval
, "linear")) {
832 /* You should set dynkomi_mask=1
833 * since this doesn't work well
834 * for white handicaps! */
835 u
->dynkomi
= uct_dynkomi_init_linear(u
, dynkomiarg
, b
);
836 } else if (!strcasecmp(optval
, "adaptive")) {
837 /* There are many more knobs to
838 * crank - see uct/dynkomi.c. */
839 u
->dynkomi
= uct_dynkomi_init_adaptive(u
, dynkomiarg
, b
);
841 fprintf(stderr
, "UCT: Invalid dynkomi mode %s\n", optval
);
844 } else if (!strcasecmp(optname
, "dynkomi_mask") && optval
) {
845 /* Bitmask of colors the player must be
846 * for dynkomi be applied; you may want
847 * to use dynkomi_mask=3 to allow dynkomi
848 * even in games where Pachi is white. */
849 u
->dynkomi_mask
= atoi(optval
);
850 } else if (!strcasecmp(optname
, "dynkomi_interval") && optval
) {
851 /* If non-zero, re-adjust dynamic komi
852 * throughout a single genmove reading,
853 * roughly every N simulations. */
854 /* XXX: Does not work with tree
855 * parallelization. */
856 u
->dynkomi_interval
= atoi(optval
);
858 /** Node value result scaling */
860 } else if (!strcasecmp(optname
, "val_scale") && optval
) {
861 /* How much of the game result value should be
862 * influenced by win size. Zero means it isn't. */
863 u
->val_scale
= atof(optval
);
864 } else if (!strcasecmp(optname
, "val_points") && optval
) {
865 /* Maximum size of win to be scaled into game
866 * result value. Zero means boardsize^2. */
867 u
->val_points
= atoi(optval
) * 2; // result values are doubled
868 } else if (!strcasecmp(optname
, "val_extra")) {
869 /* If false, the score coefficient will be simply
870 * added to the value, instead of scaling the result
871 * coefficient because of it. */
872 u
->val_extra
= !optval
|| atoi(optval
);
875 /* (Purely experimental. Does not work - yet!) */
877 } else if (!strcasecmp(optname
, "local_tree")) {
878 /* Whether to bias exploration by local tree values. */
879 u
->local_tree
= !optval
|| atoi(optval
);
880 } else if (!strcasecmp(optname
, "tenuki_d") && optval
) {
881 /* Tenuki distance at which to break the local tree. */
882 u
->tenuki_d
= atoi(optval
);
883 if (u
->tenuki_d
> TREE_NODE_D_MAX
+ 1) {
884 fprintf(stderr
, "uct: tenuki_d must not be larger than TREE_NODE_D_MAX+1 %d\n", TREE_NODE_D_MAX
+ 1);
887 } else if (!strcasecmp(optname
, "local_tree_aging") && optval
) {
888 /* How much to reduce local tree values between moves. */
889 u
->local_tree_aging
= atof(optval
);
890 } else if (!strcasecmp(optname
, "local_tree_depth_decay") && optval
) {
891 /* With value x>0, during the descent the node
892 * contributes 1/x^depth playouts in
893 * the local tree. I.e., with x>1, nodes more
894 * distant from local situation contribute more
895 * than nodes near the root. */
896 u
->local_tree_depth_decay
= atof(optval
);
897 } else if (!strcasecmp(optname
, "local_tree_allseq")) {
898 /* If disabled, only complete sequences are stored
899 * in the local tree. If this is on, also
900 * subsequences starting at each move are stored. */
901 u
->local_tree_allseq
= !optval
|| atoi(optval
);
902 } else if (!strcasecmp(optname
, "local_tree_neival")) {
903 /* If disabled, local node value is not
904 * computed just based on terminal status
905 * of the coordinate, but also its neighbors. */
906 u
->local_tree_neival
= !optval
|| atoi(optval
);
908 /** Other heuristics */
909 } else if (!strcasecmp(optname
, "significant_threshold") && optval
) {
910 /* Some heuristics (XXX: none in mainline) rely
911 * on the knowledge of the last "significant"
912 * node in the descent. Such a node is
913 * considered reasonably trustworthy to carry
914 * some meaningful information in the values
915 * of the node and its children. */
916 u
->significant_threshold
= atoi(optval
);
918 /** Distributed engine slaves setup */
920 } else if (!strcasecmp(optname
, "slave")) {
921 /* Act as slave for the distributed engine. */
922 u
->slave
= !optval
|| atoi(optval
);
923 } else if (!strcasecmp(optname
, "shared_nodes") && optval
) {
924 /* Share at most shared_nodes between master and slave at each genmoves.
925 * Must use the same value in master and slaves. */
926 u
->shared_nodes
= atoi(optval
);
927 } else if (!strcasecmp(optname
, "shared_levels") && optval
) {
928 /* Share only nodes of level <= shared_levels. */
929 u
->shared_levels
= atoi(optval
);
930 } else if (!strcasecmp(optname
, "stats_hbits") && optval
) {
931 /* Set hash table size to 2^stats_hbits for the shared stats. */
932 u
->stats_hbits
= atoi(optval
);
935 fprintf(stderr
, "uct: Invalid engine argument %s or missing value\n", optname
);
942 u
->policy
= policy_ucb1amaf_init(u
, NULL
);
944 if (!!u
->random_policy_chance
^ !!u
->random_policy
) {
945 fprintf(stderr
, "uct: Only one of random_policy and random_policy_chance is set\n");
949 if (!u
->local_tree
) {
950 /* No ltree aging. */
951 u
->local_tree_aging
= 1.0f
;
955 if (u
->pruning_threshold
< u
->max_tree_size
/ 10)
956 u
->pruning_threshold
= u
->max_tree_size
/ 10;
957 if (u
->pruning_threshold
> u
->max_tree_size
/ 2)
958 u
->pruning_threshold
= u
->max_tree_size
/ 2;
960 /* Limit pruning temp space to 20% of memory. Beyond this we discard
961 * the nodes and recompute them at the next move if necessary. */
962 u
->max_pruned_size
= u
->max_tree_size
/ 5;
963 u
->max_tree_size
-= u
->max_pruned_size
;
965 /* Reserve 5% memory in case the background free() are slower
966 * than the concurrent allocations. */
967 u
->max_tree_size
-= u
->max_tree_size
/ 20;
971 u
->prior
= uct_prior_init(NULL
, b
);
974 u
->playout
= playout_moggy_init(NULL
, b
, u
->jdict
);
975 if (!u
->playout
->debug_level
)
976 u
->playout
->debug_level
= u
->debug_level
;
978 u
->ownermap
.map
= malloc2(board_size2(b
) * sizeof(u
->ownermap
.map
[0]));
981 if (!u
->stats_hbits
) u
->stats_hbits
= DEFAULT_STATS_HBITS
;
982 if (!u
->shared_nodes
) u
->shared_nodes
= DEFAULT_SHARED_NODES
;
983 assert(u
->shared_levels
* board_bits2(b
) <= 8 * (int)sizeof(path_t
));
987 u
->dynkomi
= uct_dynkomi_init_adaptive(u
, NULL
, b
);
989 /* Some things remain uninitialized for now - the opening tbook
990 * is not loaded and the tree not set up. */
991 /* This will be initialized in setup_state() at the first move
992 * received/requested. This is because right now we are not aware
993 * about any komi or handicap setup and such. */
999 engine_uct_init(char *arg
, struct board
*b
)
1001 struct uct
*u
= uct_state_init(arg
, b
);
1002 struct engine
*e
= calloc2(1, sizeof(struct engine
));
1003 e
->name
= "UCT Engine";
1004 e
->printhook
= uct_printhook_ownermap
;
1005 e
->notify_play
= uct_notify_play
;
1008 e
->result
= uct_result
;
1009 e
->genmove
= uct_genmove
;
1010 e
->genmoves
= uct_genmoves
;
1011 e
->dead_group_list
= uct_dead_group_list
;
1015 e
->notify
= uct_notify
;
1017 const char banner
[] = "I'm playing UCT. When I'm losing, I will resign, "
1018 "if I think I win, I play until you pass. "
1019 "Anyone can send me 'winrate' in private chat to get my assessment of the position.";
1020 if (!u
->banner
) u
->banner
= "";
1021 e
->comment
= malloc2(sizeof(banner
) + strlen(u
->banner
) + 1);
1022 sprintf(e
->comment
, "%s %s", banner
, u
->banner
);