[freeciv-ai] (PR#9884) AI never breaks alliance

["Mateusz Stefek" <mstefek@xxxxxxxxx>]

<URL: http://rt.freeciv.org/Ticket/Display.html?id=9884 >

> [glip - Tue Aug 31 21:32:13 2004]:
> 
> On Tue, 31 Aug 2004, Mateusz Stefek wrote:
> 
> > In current implementation AI will break alliance only if you are not at
> > war with it's target. AI never considers it's allies as war target. This
> > should be changed. Attached patch is really simple.
> > Note that if ai.love == 96 (maximum realistic level), war desire is
> > divided by 25!. So it will really rarely happen. (You can move your
> > units into AI's territory if you want to reduce love a little)
> > 
> > I playtested it. AI broke alliance with me when I was four times as big
> > as he and the second most powerfull nation was two times smaller than
> > me. I  had also had units on its territory for few turns (love was = 70
> > in a turn when it broke alliance).
> > I think this is a step into correct direction.
I also noticed that it formed alliance with former enemies.
> It sounds like AI committing suicide...
> It either should break alliance earlier (say when human power > AI player 
> + runner-up AI) or naively hope that the big brother won't screw them
> 
I agree that AI should go to war earlier.
I hope that this patch will help.
It has to be massively playtested just like all changes in rules. It's
very hard to find correct balance.
--
mateusz

Index: advdiplomacy.c
===================================================================
RCS file: /home/freeciv/CVS/freeciv/ai/advdiplomacy.c,v
retrieving revision 1.31
diff -u -r1.31 advdiplomacy.c
--- advdiplomacy.c      31 Aug 2004 16:47:10 -0000      1.31
+++ advdiplomacy.c      31 Aug 2004 22:18:33 -0000
@@ -627,10 +627,10 @@
     }
   } players_iterate_end;
 
-  /* Modify by love */
+  /* Modify by love. Increase the divisor to make ai go to war earlier */
   kill_desire -= MAX(0, kill_desire 
                         * pplayer->ai.love[aplayer->player_no] 
-                        / 100);
+                        / 200);
 
   /* Amortize by distance */
   return amortize(kill_desire, adip->distance);
@@ -787,10 +787,6 @@
       continue;    
     }
 
-    /* Strongly prefer players we are at war with already. */
-    if (pplayers_non_attack(pplayer, aplayer)) {
-      war_desire[aplayer->player_no] /= 2;
-    }
     PLAYER_LOG(LOG_DEBUG, pplayer, ai, "Against %s we have war desire "
             "%d ", aplayer->name, war_desire[aplayer->player_no]);