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_rootseqval
= 1;
568 u
->local_tree_depth_decay
= 1.5;
570 u
->plugins
= pluginset_init(b
);
572 u
->jdict
= joseki_load(b
->size
);
575 char *optspec
, *next
= arg
;
578 next
+= strcspn(next
, ",");
579 if (*next
) { *next
++ = 0; } else { *next
= 0; }
581 char *optname
= optspec
;
582 char *optval
= strchr(optspec
, '=');
583 if (optval
) *optval
++ = 0;
587 if (!strcasecmp(optname
, "debug")) {
589 u
->debug_level
= atoi(optval
);
592 } else if (!strcasecmp(optname
, "dumpthres") && optval
) {
593 /* When dumping the UCT tree on output, include
594 * nodes with at least this many playouts.
595 * (This value is re-scaled "intelligently"
596 * in case of very large trees.) */
597 u
->dumpthres
= atoi(optval
);
598 } else if (!strcasecmp(optname
, "resign_threshold") && optval
) {
599 /* Resign when this ratio of games is lost
600 * after GJ_MINGAMES sample is taken. */
601 u
->resign_threshold
= atof(optval
);
602 } else if (!strcasecmp(optname
, "sure_win_threshold") && optval
) {
603 /* Stop reading when this ratio of games is won
604 * after PLAYOUT_EARLY_BREAK_MIN sample is
605 * taken. (Prevents stupid time losses,
606 * friendly to human opponents.) */
607 u
->sure_win_threshold
= atof(optval
);
608 } else if (!strcasecmp(optname
, "force_seed") && optval
) {
609 /* Set RNG seed at the tree setup. */
610 u
->force_seed
= atoi(optval
);
611 } else if (!strcasecmp(optname
, "no_tbook")) {
612 /* Disable UCT opening tbook. */
614 } else if (!strcasecmp(optname
, "pass_all_alive")) {
615 /* Whether to consider passing only after all
616 * dead groups were removed from the board;
617 * this is like all genmoves are in fact
618 * kgs-genmove_cleanup. */
619 u
->pass_all_alive
= !optval
|| atoi(optval
);
620 } else if (!strcasecmp(optname
, "territory_scoring")) {
621 /* Use territory scoring (default is area scoring).
622 * An explicit kgs-rules command overrides this. */
623 u
->territory_scoring
= !optval
|| atoi(optval
);
624 } else if (!strcasecmp(optname
, "banner") && optval
) {
625 /* Additional banner string. This must come as the
626 * last engine parameter. */
627 if (*next
) *--next
= ',';
628 u
->banner
= strdup(optval
);
630 } else if (!strcasecmp(optname
, "plugin") && optval
) {
631 /* Load an external plugin; filename goes before the colon,
632 * extra arguments after the colon. */
633 char *pluginarg
= strchr(optval
, ':');
636 plugin_load(u
->plugins
, optval
, pluginarg
);
638 /** UCT behavior and policies */
640 } else if ((!strcasecmp(optname
, "policy")
641 /* Node selection policy. ucb1amaf is the
642 * default policy implementing RAVE, while
643 * ucb1 is the simple exploration/exploitation
644 * policy. Policies can take further extra
646 || !strcasecmp(optname
, "random_policy")) && optval
) {
647 /* A policy to be used randomly with small
648 * chance instead of the default policy. */
649 char *policyarg
= strchr(optval
, ':');
650 struct uct_policy
**p
= !strcasecmp(optname
, "policy") ? &u
->policy
: &u
->random_policy
;
653 if (!strcasecmp(optval
, "ucb1")) {
654 *p
= policy_ucb1_init(u
, policyarg
);
655 } else if (!strcasecmp(optval
, "ucb1amaf")) {
656 *p
= policy_ucb1amaf_init(u
, policyarg
);
658 fprintf(stderr
, "UCT: Invalid tree policy %s\n", optval
);
661 } else if (!strcasecmp(optname
, "playout") && optval
) {
662 /* Random simulation (playout) policy.
663 * moggy is the default policy with large
664 * amount of domain-specific knowledge and
665 * heuristics. light is a simple uniformly
666 * random move selection policy. */
667 char *playoutarg
= strchr(optval
, ':');
670 if (!strcasecmp(optval
, "moggy")) {
671 u
->playout
= playout_moggy_init(playoutarg
, b
, u
->jdict
);
672 } else if (!strcasecmp(optval
, "light")) {
673 u
->playout
= playout_light_init(playoutarg
, b
);
675 fprintf(stderr
, "UCT: Invalid playout policy %s\n", optval
);
678 } else if (!strcasecmp(optname
, "prior") && optval
) {
679 /* Node priors policy. When expanding a node,
680 * it will seed node values heuristically
681 * (most importantly, based on playout policy
682 * opinion, but also with regard to other
683 * things). See uct/prior.c for details.
684 * Use prior=eqex=0 to disable priors. */
685 u
->prior
= uct_prior_init(optval
, b
);
686 } else if (!strcasecmp(optname
, "mercy") && optval
) {
687 /* Minimal difference of black/white captures
688 * to stop playout - "Mercy Rule". Speeds up
689 * hopeless playouts at the expense of some
691 u
->mercymin
= atoi(optval
);
692 } else if (!strcasecmp(optname
, "gamelen") && optval
) {
693 /* Maximum length of single simulation
695 u
->gamelen
= atoi(optval
);
696 } else if (!strcasecmp(optname
, "expand_p") && optval
) {
697 /* Expand UCT nodes after it has been
698 * visited this many times. */
699 u
->expand_p
= atoi(optval
);
700 } else if (!strcasecmp(optname
, "random_policy_chance") && optval
) {
701 /* If specified (N), with probability 1/N, random_policy policy
702 * descend is used instead of main policy descend; useful
703 * if specified policy (e.g. UCB1AMAF) can make unduly biased
704 * choices sometimes, you can fall back to e.g.
705 * random_policy=UCB1. */
706 u
->random_policy_chance
= atoi(optval
);
708 /** General AMAF behavior */
709 /* (Only relevant if the policy supports AMAF.
710 * More variables can be tuned as policy
713 } else if (!strcasecmp(optname
, "playout_amaf")) {
714 /* Whether to include random playout moves in
715 * AMAF as well. (Otherwise, only tree moves
716 * are included in AMAF. Of course makes sense
717 * only in connection with an AMAF policy.) */
718 /* with-without: 55.5% (+-4.1) */
719 if (optval
&& *optval
== '0')
720 u
->playout_amaf
= false;
722 u
->playout_amaf
= true;
723 } else if (!strcasecmp(optname
, "playout_amaf_nakade")) {
724 /* Whether to include nakade moves from playouts
725 * in the AMAF statistics; this tends to nullify
726 * the playout_amaf effect by adding too much
728 if (optval
&& *optval
== '0')
729 u
->playout_amaf_nakade
= false;
731 u
->playout_amaf_nakade
= true;
732 } else if (!strcasecmp(optname
, "playout_amaf_cutoff") && optval
) {
733 /* Keep only first N% of playout stage AMAF
735 u
->playout_amaf_cutoff
= atoi(optval
);
736 } else if (!strcasecmp(optname
, "amaf_prior") && optval
) {
737 /* In node policy, consider prior values
738 * part of the real result term or part
739 * of the AMAF term? */
740 u
->amaf_prior
= atoi(optval
);
742 /** Performance and memory management */
744 } else if (!strcasecmp(optname
, "threads") && optval
) {
745 /* By default, Pachi will run with only single
746 * tree search thread! */
747 u
->threads
= atoi(optval
);
748 } else if (!strcasecmp(optname
, "thread_model") && optval
) {
749 if (!strcasecmp(optval
, "tree")) {
750 /* Tree parallelization - all threads
751 * grind on the same tree. */
752 u
->thread_model
= TM_TREE
;
754 } else if (!strcasecmp(optval
, "treevl")) {
755 /* Tree parallelization, but also
756 * with virtual losses - this discou-
757 * rages most threads choosing the
758 * same tree branches to read. */
759 u
->thread_model
= TM_TREEVL
;
761 fprintf(stderr
, "UCT: Invalid thread model %s\n", optval
);
764 } else if (!strcasecmp(optname
, "virtual_loss")) {
765 /* Number of virtual losses added before evaluating a node. */
766 u
->virtual_loss
= !optval
|| atoi(optval
);
767 } else if (!strcasecmp(optname
, "pondering")) {
768 /* Keep searching even during opponent's turn. */
769 u
->pondering_opt
= !optval
|| atoi(optval
);
770 } else if (!strcasecmp(optname
, "max_tree_size") && optval
) {
771 /* Maximum amount of memory [MiB] consumed by the move tree.
772 * For fast_alloc it includes the temp tree used for pruning.
773 * Default is 3072 (3 GiB). */
774 u
->max_tree_size
= atol(optval
) * 1048576;
775 } else if (!strcasecmp(optname
, "fast_alloc")) {
776 u
->fast_alloc
= !optval
|| atoi(optval
);
777 } else if (!strcasecmp(optname
, "pruning_threshold") && optval
) {
778 /* Force pruning at beginning of a move if the tree consumes
779 * more than this [MiB]. Default is 10% of max_tree_size.
780 * Increase to reduce pruning time overhead if memory is plentiful.
781 * This option is meaningful only for fast_alloc. */
782 u
->pruning_threshold
= atol(optval
) * 1048576;
786 } else if (!strcasecmp(optname
, "best2_ratio") && optval
) {
787 /* If set, prolong simulating while
788 * first_best/second_best playouts ratio
789 * is less than best2_ratio. */
790 u
->best2_ratio
= atof(optval
);
791 } else if (!strcasecmp(optname
, "bestr_ratio") && optval
) {
792 /* If set, prolong simulating while
793 * best,best_best_child values delta
794 * is more than bestr_ratio. */
795 u
->bestr_ratio
= atof(optval
);
796 } else if (!strcasecmp(optname
, "max_maintime_ratio") && optval
) {
797 /* If set and while not in byoyomi, prolong simulating no more than
798 * max_maintime_ratio times the normal desired thinking time. */
799 u
->max_maintime_ratio
= atof(optval
);
800 } else if (!strcasecmp(optname
, "fuseki_end") && optval
) {
801 /* At the very beginning it's not worth thinking
802 * too long because the playout evaluations are
803 * very noisy. So gradually increase the thinking
804 * time up to maximum when fuseki_end percent
805 * of the board has been played.
806 * This only applies if we are not in byoyomi. */
807 u
->fuseki_end
= atoi(optval
);
808 } else if (!strcasecmp(optname
, "yose_start") && optval
) {
809 /* When yose_start percent of the board has been
810 * played, or if we are in byoyomi, stop spending
811 * more time and spread the remaining time
813 * Between fuseki_end and yose_start, we spend
814 * a constant proportion of the remaining time
815 * on each move. (yose_start should actually
816 * be much earlier than when real yose start,
817 * but "yose" is a good short name to convey
819 u
->yose_start
= atoi(optval
);
823 } else if (!strcasecmp(optname
, "dynkomi") && optval
) {
824 /* Dynamic komi approach; there are multiple
825 * ways to adjust komi dynamically throughout
826 * play. We currently support two: */
827 char *dynkomiarg
= strchr(optval
, ':');
830 if (!strcasecmp(optval
, "none")) {
831 u
->dynkomi
= uct_dynkomi_init_none(u
, dynkomiarg
, b
);
832 } else if (!strcasecmp(optval
, "linear")) {
833 /* You should set dynkomi_mask=1
834 * since this doesn't work well
835 * for white handicaps! */
836 u
->dynkomi
= uct_dynkomi_init_linear(u
, dynkomiarg
, b
);
837 } else if (!strcasecmp(optval
, "adaptive")) {
838 /* There are many more knobs to
839 * crank - see uct/dynkomi.c. */
840 u
->dynkomi
= uct_dynkomi_init_adaptive(u
, dynkomiarg
, b
);
842 fprintf(stderr
, "UCT: Invalid dynkomi mode %s\n", optval
);
845 } else if (!strcasecmp(optname
, "dynkomi_mask") && optval
) {
846 /* Bitmask of colors the player must be
847 * for dynkomi be applied; you may want
848 * to use dynkomi_mask=3 to allow dynkomi
849 * even in games where Pachi is white. */
850 u
->dynkomi_mask
= atoi(optval
);
851 } else if (!strcasecmp(optname
, "dynkomi_interval") && optval
) {
852 /* If non-zero, re-adjust dynamic komi
853 * throughout a single genmove reading,
854 * roughly every N simulations. */
855 /* XXX: Does not work with tree
856 * parallelization. */
857 u
->dynkomi_interval
= atoi(optval
);
859 /** Node value result scaling */
861 } else if (!strcasecmp(optname
, "val_scale") && optval
) {
862 /* How much of the game result value should be
863 * influenced by win size. Zero means it isn't. */
864 u
->val_scale
= atof(optval
);
865 } else if (!strcasecmp(optname
, "val_points") && optval
) {
866 /* Maximum size of win to be scaled into game
867 * result value. Zero means boardsize^2. */
868 u
->val_points
= atoi(optval
) * 2; // result values are doubled
869 } else if (!strcasecmp(optname
, "val_extra")) {
870 /* If false, the score coefficient will be simply
871 * added to the value, instead of scaling the result
872 * coefficient because of it. */
873 u
->val_extra
= !optval
|| atoi(optval
);
876 /* (Purely experimental. Does not work - yet!) */
878 } else if (!strcasecmp(optname
, "local_tree") && optval
) {
879 /* Whether to bias exploration by local tree values
880 * (must be supported by the used policy).
882 * 1: Do, value = result.
883 * Try to temper the result:
884 * 2: Do, value = 0.5+(result-expected)/2.
885 * 3: Do, value = 0.5+bzz((result-expected)^2).
886 * 4: Do, value = 0.5+sqrt(result-expected)/2. */
887 u
->local_tree
= atoi(optval
);
888 } else if (!strcasecmp(optname
, "tenuki_d") && optval
) {
889 /* Tenuki distance at which to break the local tree. */
890 u
->tenuki_d
= atoi(optval
);
891 if (u
->tenuki_d
> TREE_NODE_D_MAX
+ 1) {
892 fprintf(stderr
, "uct: tenuki_d must not be larger than TREE_NODE_D_MAX+1 %d\n", TREE_NODE_D_MAX
+ 1);
895 } else if (!strcasecmp(optname
, "local_tree_aging") && optval
) {
896 /* How much to reduce local tree values between moves. */
897 u
->local_tree_aging
= atof(optval
);
898 } else if (!strcasecmp(optname
, "local_tree_depth_decay") && optval
) {
899 /* With value x>0, during the descent the node
900 * contributes 1/x^depth playouts in
901 * the local tree. I.e., with x>1, nodes more
902 * distant from local situation contribute more
903 * than nodes near the root. */
904 u
->local_tree_depth_decay
= atof(optval
);
905 } else if (!strcasecmp(optname
, "local_tree_allseq")) {
906 /* If disabled, only complete sequences are stored
907 * in the local tree. If this is on, also
908 * subsequences starting at each move are stored. */
909 u
->local_tree_allseq
= !optval
|| atoi(optval
);
910 } else if (!strcasecmp(optname
, "local_tree_rootseqval")) {
911 /* If disabled, expected node value is computed by
912 * summing up values through the whole descent.
913 * If enabled, expected node value for
914 * each sequence is the value at the root of the
916 u
->local_tree_rootseqval
= !optval
|| atoi(optval
);
918 /** Other heuristics */
919 } else if (!strcasecmp(optname
, "significant_threshold") && optval
) {
920 /* Some heuristics (XXX: none in mainline) rely
921 * on the knowledge of the last "significant"
922 * node in the descent. Such a node is
923 * considered reasonably trustworthy to carry
924 * some meaningful information in the values
925 * of the node and its children. */
926 u
->significant_threshold
= atoi(optval
);
928 /** Distributed engine slaves setup */
930 } else if (!strcasecmp(optname
, "slave")) {
931 /* Act as slave for the distributed engine. */
932 u
->slave
= !optval
|| atoi(optval
);
933 } else if (!strcasecmp(optname
, "shared_nodes") && optval
) {
934 /* Share at most shared_nodes between master and slave at each genmoves.
935 * Must use the same value in master and slaves. */
936 u
->shared_nodes
= atoi(optval
);
937 } else if (!strcasecmp(optname
, "shared_levels") && optval
) {
938 /* Share only nodes of level <= shared_levels. */
939 u
->shared_levels
= atoi(optval
);
940 } else if (!strcasecmp(optname
, "stats_hbits") && optval
) {
941 /* Set hash table size to 2^stats_hbits for the shared stats. */
942 u
->stats_hbits
= atoi(optval
);
945 fprintf(stderr
, "uct: Invalid engine argument %s or missing value\n", optname
);
952 u
->policy
= policy_ucb1amaf_init(u
, NULL
);
954 if (!!u
->random_policy_chance
^ !!u
->random_policy
) {
955 fprintf(stderr
, "uct: Only one of random_policy and random_policy_chance is set\n");
959 if (!u
->local_tree
) {
960 /* No ltree aging. */
961 u
->local_tree_aging
= 1.0f
;
965 if (u
->pruning_threshold
< u
->max_tree_size
/ 10)
966 u
->pruning_threshold
= u
->max_tree_size
/ 10;
967 if (u
->pruning_threshold
> u
->max_tree_size
/ 2)
968 u
->pruning_threshold
= u
->max_tree_size
/ 2;
970 /* Limit pruning temp space to 20% of memory. Beyond this we discard
971 * the nodes and recompute them at the next move if necessary. */
972 u
->max_pruned_size
= u
->max_tree_size
/ 5;
973 u
->max_tree_size
-= u
->max_pruned_size
;
975 /* Reserve 5% memory in case the background free() are slower
976 * than the concurrent allocations. */
977 u
->max_tree_size
-= u
->max_tree_size
/ 20;
981 u
->prior
= uct_prior_init(NULL
, b
);
984 u
->playout
= playout_moggy_init(NULL
, b
, u
->jdict
);
985 if (!u
->playout
->debug_level
)
986 u
->playout
->debug_level
= u
->debug_level
;
988 u
->ownermap
.map
= malloc2(board_size2(b
) * sizeof(u
->ownermap
.map
[0]));
991 if (!u
->stats_hbits
) u
->stats_hbits
= DEFAULT_STATS_HBITS
;
992 if (!u
->shared_nodes
) u
->shared_nodes
= DEFAULT_SHARED_NODES
;
993 assert(u
->shared_levels
* board_bits2(b
) <= 8 * (int)sizeof(path_t
));
997 u
->dynkomi
= uct_dynkomi_init_adaptive(u
, NULL
, b
);
999 /* Some things remain uninitialized for now - the opening tbook
1000 * is not loaded and the tree not set up. */
1001 /* This will be initialized in setup_state() at the first move
1002 * received/requested. This is because right now we are not aware
1003 * about any komi or handicap setup and such. */
1009 engine_uct_init(char *arg
, struct board
*b
)
1011 struct uct
*u
= uct_state_init(arg
, b
);
1012 struct engine
*e
= calloc2(1, sizeof(struct engine
));
1013 e
->name
= "UCT Engine";
1014 e
->printhook
= uct_printhook_ownermap
;
1015 e
->notify_play
= uct_notify_play
;
1018 e
->result
= uct_result
;
1019 e
->genmove
= uct_genmove
;
1020 e
->genmoves
= uct_genmoves
;
1021 e
->dead_group_list
= uct_dead_group_list
;
1025 e
->notify
= uct_notify
;
1027 const char banner
[] = "I'm playing UCT. When I'm losing, I will resign, "
1028 "if I think I win, I play until you pass. "
1029 "Anyone can send me 'winrate' in private chat to get my assessment of the position.";
1030 if (!u
->banner
) u
->banner
= "";
1031 e
->comment
= malloc2(sizeof(banner
) + strlen(u
->banner
) + 1);
1032 sprintf(e
->comment
, "%s %s", banner
, u
->banner
);