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