RE: [gnugo-devel] nando_3_9.4

[Arend Bayer]

There are certainly lots of places where the patch could get extended,
but I guess it would be best think it would be best if we could merge
s.th. into CVS before we start doing that.

That's why I'd suggest a minimal fix for the problem I'd described
(about setting the whole dragon critical). Instead of touching
influence.c we could do a workaround as below (untested and not yet
working, as owl_reasons() ignores all non-critical dragons). I think
this should give about reasonable valuations for all cases.

Would that make sense?

Arend


--- engine/dragon.c.orig        Wed Sep 18 14:32:43 2002
+++ engine/dragon.c     Wed Sep 18 14:33:56 2002
@@ -401,7 +401,10 @@
                               &dragon[str].owl_defense_certain, &kworm);
            if (dcode != 0) {
              if (defense_point != NO_MOVE) {
-               dragon[str].owl_status = CRITICAL;
+               if (acode == GAIN)
+                 dragon[str].owl_status = ALIVE;
+               else
+                 dragon[str].owl_status = CRITICAL;
                dragon[str].owl_defense_point = defense_point;
                dragon[str].owl_defense_code = dcode;
                dragon[str].owl_defense_kworm = kworm;
--- engine/value_moves.c.orig   Wed Sep 18 14:32:49 2002
+++ engine/value_moves.c        Wed Sep 18 14:46:45 2002
@@ -1587,6 +1587,19 @@
     case OWL_DEFEND_MOVE_LOSS:
       aa = dragons[move_reasons[r].what];

+      /* FIXME: This is to handle a defense of a dragon where only a
+       * tail can be captured by the opponent (i.e. attack code GAIN).
+       * Should be included with the territorial evaluation in influence.c
+       * instead.
+       */
+      if (move_reasons[r].type == OWL_DEFEND_MOVE
+         && dragon[aa].status == ALIVE
+         && dragon[aa].owl_attack_code == GAIN) {
+       ASSERT_ON_BOARD1(dragon[aa].owl_attack_kworm);
+       tot_value += worm[dragon[aa].owl_attack_kworm].effective_size;
+       break;
+      }
+
       /* If the dragon is a single ko stone, the owl code currently
        * won't detect that the owl attack is conditional. As a
        * workaround we deduct 0.5 points for the move here, but only