[freeciv-ai] (PR#9808) AI should remove shared vision more often

["Mateusz Stefek" <mstefek@xxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=9808 >

AI doesn't share vision with you if it's not safe, but once shared
vision is accepted AI will never remove it even if it became dangerous.
For example if AI's ally give shared vision to someone, who is neutral
to AI.  This may result in vision shared beetwen enemies (and is in fact
very often in auto-games).
I belive that the attached patch helps
--
mateusz

Index: advdiplomacy.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/ai/advdiplomacy.c,v
retrieving revision 1.27
diff -u -r1.27 advdiplomacy.c
--- advdiplomacy.c      30 Jul 2004 20:40:49 -0000      1.27
+++ advdiplomacy.c      25 Aug 2004 11:25:09 -0000
@@ -1006,10 +1006,16 @@
     clause.from = pplayer;
     clause.value = 0;
 
-    /* Remove shared vision if we are not allied. */
-    if (!pplayers_allied(pplayer, aplayer)
-        && gives_shared_vision(pplayer, aplayer)) {
-      remove_shared_vision(pplayer, aplayer);
+    /* Remove shared vision if we are not allied or it is no longer safe. */
+    if (gives_shared_vision(pplayer, aplayer)) {
+      if (!pplayers_allied(pplayer, aplayer)) {
+        remove_shared_vision(pplayer, aplayer);
+      } else if (!shared_vision_is_safe(pplayer, aplayer)) {
+        notify(aplayer, _("*%s (AI)* Sorry, sharing vision with you "
+                           "is no longer safe to me"),
+              pplayer->name);
+       remove_shared_vision(pplayer, aplayer);
+      }
     }
 
     /* No peace to enemies of our allies... or pointless peace. */