mq.h

   1 #ifndef PACHI_MQ_H
   2 #define PACHI_MQ_H
   3
   4 /* Move queues; in fact, they are more like move lists, usually used
   5  * to accumulate equally good move candidates, then choosing from them
   6  * randomly. But they are also used to juggle group lists (using the
   7  * fact that coord_t == group_t). */
   8
   9 /* Warning: move_queue is further specialized upon in libmap_mq.
  10  * Take care of that when doing any changes here. */
  11
  12 #include "move.h"
  13 #include "random.h"
  14
  15 #define MQL 512 /* XXX: On larger board this might not be enough. */
  16 struct move_queue {
  17         unsigned int moves;
  18         coord_t move[MQL];
  19         /* Each move can have an optional tag or set of tags.
  20          * The usage of these is user-dependent. */
  21         unsigned char tag[MQL];
  22 };
  23
  24 /* Pick a random move from the queue. */
  25 static coord_t mq_pick(struct move_queue *q);
  26
  27 /* Add a move to the queue. */
  28 static void mq_add(struct move_queue *q, coord_t c, unsigned char tag);
  29
  30 /* Cat two queues together. */
  31 static void mq_append(struct move_queue *qd, struct move_queue *qs);
  32
  33 /* Check if the last move in queue is not a dupe, and remove it
  34  * in that case. */
  35 static void mq_nodup(struct move_queue *q);
  36
  37 /* Print queue contents on stderr. */
  38 static void mq_print(struct move_queue *q, struct board *b, char *label);
  39
  40
  41 /* Variations of the above that allow move weighting. */
  42 /* XXX: The "kinds of move queue" issue (it's even worse in some other
  43  * branches) is one of the few good arguments for C++ in Pachi...
  44  * At least rewrite it to be less hacky and maybe make a move_gamma_queue
  45  * that encapsulates move_queue. */
  46
  47 static coord_t mq_gamma_pick(struct move_queue *q, fixp_t *gammas);
  48 static void mq_gamma_add(struct move_queue *q, fixp_t *gammas, coord_t c, double gamma, unsigned char tag);
  49 static void mq_gamma_print(struct move_queue *q, fixp_t *gammas, struct board *b, char *label);
  50
  51
  52 static inline coord_t
  53 mq_pick(struct move_queue *q)
  54 {
  55         return q->moves ? q->move[fast_random(q->moves)] : pass;
  56 }
  57
  58 static inline void
  59 mq_add(struct move_queue *q, coord_t c, unsigned char tag)
  60 {
  61         assert(q->moves < MQL);
  62         q->tag[q->moves] = tag;
  63         q->move[q->moves++] = c;
  64 }
  65
  66 static inline void
  67 mq_append(struct move_queue *qd, struct move_queue *qs)
  68 {
  69         assert(qd->moves + qs->moves < MQL);
  70         memcpy(&qd->tag[qd->moves], qs->tag, qs->moves * sizeof(*qs->tag));
  71         memcpy(&qd->move[qd->moves], qs->move, qs->moves * sizeof(*qs->move));
  72         qd->moves += qs->moves;
  73 }
  74
  75 static inline void
  76 mq_nodup(struct move_queue *q)
  77 {
  78         for (unsigned int i = 1; i < 4; i++) {
  79                 if (q->moves <= i)
  80                         return;
  81                 if (q->move[q->moves - 1 - i] == q->move[q->moves - 1]) {
  82                         q->tag[q->moves - 1 - i] |= q->tag[q->moves - 1];
  83                         q->moves--;
  84                         return;
  85                 }
  86         }
  87 }
  88
  89 static inline void
  90 mq_print(struct move_queue *q, struct board *b, char *label)
  91 {
  92         fprintf(stderr, "%s candidate moves: ", label);
  93         for (unsigned int i = 0; i < q->moves; i++) {
  94                 fprintf(stderr, "%s ", coord2sstr(q->move[i], b));
  95         }
  96         fprintf(stderr, "\n");
  97 }
  98
  99 static inline coord_t
 100 mq_gamma_pick(struct move_queue *q, fixp_t *gammas)
 101 {
 102         if (!q->moves)
 103                 return pass;
 104         fixp_t total = 0;
 105         for (unsigned int i = 0; i < q->moves; i++) {
 106                 total += gammas[i];
 107         }
 108         if (!total)
 109                 return pass;
 110         fixp_t stab = fast_irandom(total);
 111         for (unsigned int i = 0; i < q->moves; i++) {
 112                 if (stab < gammas[i])
 113                         return q->move[i];
 114                 stab -= gammas[i];
 115         }
 116         assert(0);
 117         return pass;
 118 }
 119
 120 static inline void
 121 mq_gamma_add(struct move_queue *q, fixp_t *gammas, coord_t c, double gamma, unsigned char tag)
 122 {
 123         mq_add(q, c, tag);
 124         gammas[q->moves - 1] = double_to_fixp(gamma);
 125 }
 126
 127 static inline void
 128 mq_gamma_print(struct move_queue *q, fixp_t *gammas, struct board *b, char *label)
 129 {
 130         fprintf(stderr, "%s candidate moves: ", label);
 131         for (unsigned int i = 0; i < q->moves; i++) {
 132                 fprintf(stderr, "%s(%.3f) ", coord2sstr(q->move[i], b), fixp_to_double(gammas[i]));
 133         }
 134         fprintf(stderr, "\n");
 135 }
 136
 137 #endif