Ticket #173: lively-stones-2a.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;