Ticket #173: lively-stones-2.diff

engine/value_moves.c

@@ -2977 +2977 @@
         || (owl_move_reason_known(pos, aa)
             && dragon[aa].status == CRITICAL)
         || move_reason_known(pos, SEMEAI_MOVE, aa)) {
+      float excess_value;
+      int our_dragon = (color == worm[aa].color);
+      float dragon_ter_val = 2 * DRAGON2(aa).strategic_size;
+
+      if ((our_dragon && defense_move_known(pos, aa) == WIN)
+          || (!our_dragon && attack_move_known(pos, aa) == WIN)) {
+        excess_value = dragon_ter_val - move[pos].territorial_value;
+        if (excess_value > 0.0) {
+          /* We haven't counted all the territorial value, the most probably
+           * because of ko situations - repair it here.
+           * FIXME: We should count values of all ko threats to know how
+           * much we really gain. As for now 0.75 factor is used. */
+          excess_value *= 0.75;
+          TRACE("  %1m: %f - territory underestimation bonus for %1m\n", pos,
+                excess_value, aa);
+          tot_value += excess_value;
+        }
+      }
+
       /* But if the strategical value was larger than the territorial
        * value (e.g. because connecting to strong dragon) we award the
        * excess value as a bonus.
        */
-      float excess_value = (dragon_value[aa] - 
-                            2 * DRAGON2(aa).strategic_size);
+      excess_value = (dragon_value[aa] - dragon_ter_val);
       if (excess_value > 0.0) {
         TRACE("  %1m: %f - strategic bonus for %1m\n", pos, excess_value, aa);
         tot_value += excess_value;

engine/worm.c

@@ -1706 +1706 @@
 }
 
 
+/* Find stones, that could live for sure, if player (color) moves
+ * first.
+ */
+
 void
 get_lively_stones(int color, signed char safe_stones[BOARDMAX])
 {
@@ -1713 +1717 @@
   memset(safe_stones, 0, BOARDMAX * sizeof(*safe_stones));
   for (pos = BOARDMIN; pos < BOARDMAX; pos++)
     if (IS_STONE(board[pos]) && find_origin(pos) == pos) {
-      if ((stackp == 0 && worm[pos].attack_codes[0] == 0) || !attack(pos, NULL)
+      if ((stackp == 0 && worm[pos].attack_codes[0] == 0)
+           || !attack(pos, NULL)
           || (board[pos] == color
-              && ((stackp == 0 && worm[pos].defense_codes[0] != 0)
-                  || find_defense(pos, NULL))))
+              && ((stackp == 0 && worm[pos].defense_codes[0] == WIN)
+                  || find_defense(pos, NULL) == WIN)))
         mark_string(pos, safe_stones, 1);
     }
 }