Index: liberty.h
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/liberty.h,v
retrieving revision 1.184
diff -u -r1.184 liberty.h
--- liberty.h	26 Jun 2003 20:24:03 -0000	1.184
+++ liberty.h	6 Jul 2003 01:53:44 -0000
@@ -1009,6 +1009,7 @@
   int semeai_defense_certain;
   int semeai_attack_point; /* Move found by semeai code to kill dragon      
  */
   int semeai_attack_certain;
+  int semeai_target;       /* The opponent dragon involved in the semeai    
  */
   int owl_threat_status;   /* CAN_THREATEN_ATTACK or CAN_THREATEN_DEFENSE   
  */
   int owl_status;          /* (ALIVE, DEAD, UNKNOWN, CRITICAL, UNCHECKED)   
  */
   int owl_attack_point;    /* vital point for attack                        
  */

Index: semeai.c
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/semeai.c,v
retrieving revision 1.57
diff -u -r1.57 semeai.c
--- semeai.c	18 Jul 2003 18:59:21 -0000	1.57
+++ semeai.c	4 Aug 2003 22:30:02 -0000
@@ -194,6 +194,7 @@
     int attack_move = PASS_MOVE;
     int defense_certain = 0;
     int attack_certain = 0;
+    int semeai_target = 0;

     for (d2 = 0; d2 < num_dragons; d2++) {
       if (semeai_results_first[d1][d2] == -1)
@@ -207,6 +208,7 @@
	best_defense = semeai_results_first[d1][d2];
	defense_move = semeai_move[d1][d2];
	defense_certain = semeai_certain[d1][d2];
+	semeai_target = dragon2[d2].origin;
       }
       if (best_attack < semeai_results_second[d2][d1]
	  || (best_attack == semeai_results_second[d2][d1]
@@ -214,6 +216,7 @@
	best_attack = semeai_results_second[d2][d1];
	attack_move = semeai_move[d2][d1];
	attack_certain = semeai_certain[d2][d1];
+	semeai_target = dragon2[d2].origin;
       }
     }

@@ -225,6 +228,7 @@
	dragon2[d1].semeai_defense_certain = defense_certain;
	dragon2[d1].semeai_attack_point = attack_move;
	dragon2[d1].semeai_attack_certain = attack_certain;
+	dragon2[d1].semeai_target = semeai_target;
       }
       else if (best_attack == 0 && attack_certain)
	update_status(DRAGON(d1).origin, ALIVE, ALIVE);
@@ -243,6 +247,10 @@
{
   int other = OTHER_COLOR(color);
   int d;
+  int liberties;
+  int libs[MAXLIBS];
+  int r;
+  int resulta, resultb, semeai_move, s_result_certain;

   for (d = 0; d < number_of_dragons; d++)
     if (dragon2[d].semeai && DRAGON(d).status == CRITICAL) {
@@ -251,18 +259,66 @@
	  && (dragon2[d].owl_defense_point == NO_MOVE
	      || dragon2[d].semeai_defense_certain >=
	         dragon2[d].owl_defense_certain)) {
-	add_semeai_move(dragon2[d].semeai_defense_point, dragon2[d].origin);
+	/* My dragon can be defended */
+        add_semeai_move(dragon2[d].semeai_defense_point, 
dragon2[d].origin);
	DEBUG(DEBUG_SEMEAI, "Adding semeai defense move for %1m at %1m\n",
-	      DRAGON(d).origin, dragon2[d].semeai_defense_point);
+	    DRAGON(d).origin, dragon2[d].semeai_defense_point);
+	if (liberty_of_dragon(dragon2[d].semeai_defense_point, 
dragon2[d].semeai_target)
+	   && !liberty_of_dragon(dragon2[d].semeai_defense_point, 
dragon2[d].origin)
+	   && !is_self_atari(dragon2[d].semeai_defense_point, color)) {
+
+	  /* if this is a move to fill the non-common liberties of the target,
+	     and is not a ko or snap-back, then we try all non-common liberties
+	     of the target and put all winning moves to the move list */
+
+          liberties = findlib(dragon2[d].semeai_target, MAXLIBS, libs);
+
+          for (r = 0; r < liberties; r++)
+            if (!liberty_of_dragon(libs[r], dragon2[d].origin)
+              && !is_self_atari(libs[r], color)
+              && libs[r] != dragon2[d].semeai_defense_point) {
+
+              owl_analyze_semeai_after_move(libs[r], color, 
dragon2[d].semeai_target,
+			      dragon2[d].origin, &resulta, &resultb, &semeai_move,
+			      1, &s_result_certain);
+              if (resulta == 0 && resultb == 0) {
+	        add_semeai_move(libs[r], dragon2[d].origin);
+	        DEBUG(DEBUG_SEMEAI, "Adding semeai defense move for %1m at %1m\n",
+	            DRAGON(d).origin, libs[r]);
+	      }
+            }
+	}
       }
       else if (DRAGON(d).color == other
	       && dragon2[d].semeai_attack_point
	       && (dragon2[d].owl_attack_point == NO_MOVE
		   || dragon2[d].semeai_attack_certain >=
		      dragon2[d].owl_attack_certain)) {
+	/* Your dragon can be attacked */
	add_semeai_move(dragon2[d].semeai_attack_point, dragon2[d].origin);
	DEBUG(DEBUG_SEMEAI, "Adding semeai attack move for %1m at %1m\n",
	      DRAGON(d).origin, dragon2[d].semeai_attack_point);
+	if (liberty_of_dragon(dragon2[d].semeai_attack_point, dragon2[d].origin)
+	   && !liberty_of_dragon(dragon2[d].semeai_attack_point, 
dragon2[d].semeai_target)
+	   && !is_self_atari(dragon2[d].semeai_attack_point, color)) {
+
+          liberties = findlib(dragon2[d].origin, MAXLIBS, libs);
+
+          for (r = 0; r < liberties; r++)
+            if (!liberty_of_dragon(libs[r], dragon2[d].semeai_target)
+              && !is_self_atari(libs[r], color)
+              && libs[r] != dragon2[d].semeai_attack_point) {
+
+              owl_analyze_semeai_after_move(libs[r], color, 
dragon2[d].origin,
+			      dragon2[d].semeai_target, &resulta, &resultb, &semeai_move,
+			      1, &s_result_certain);
+              if (resulta == 0 && resultb == 0) {
+	        add_semeai_move(libs[r], dragon2[d].origin);
+	        DEBUG(DEBUG_SEMEAI, "Adding semeai attack move for %1m at %1m\n",
+	            DRAGON(d).origin, libs[r]);
+	      }
+            }
+	}
       }
     }
}

Index: strategy.tst
===================================================================
RCS file: /cvsroot/gnugo/gnugo/regression/strategy.tst,v
retrieving revision 1.51
diff -u -r1.51 strategy.tst
--- strategy.tst        22 Jun 2003 17:12:12 -0000      1.51
+++ strategy.tst        6 Jul 2003 01:07:03 -0000
@@ -286,9 +286,10 @@
#? [G2]*

# G17/G18 and C1 are both huge.
+# H1 is absolutely better than C1 /spl
loadsgf games/strategy11.sgf 127
45 gg_genmove black
-#? [G17|G18|C1]
+#? [G17|G18|H1]

loadsgf games/strategy11.sgf 245
46 gg_genmove black