From: H.G. Muller <h.g.muller@hccnet.nl>
Date: Wed, 13 Feb 2013 22:22:03 +0000 (+0100)
Subject: Fix promotion bonus
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=319c6cd9990e350a23689b30053b25660c2c3d8f;p=fairymax.git

Fix promotion bonus

In its search Fairy-Max always promotes to 'Queen' and gives itself 768 cP
bonus for that. (Which is about right for the original micro-Max Q=851
and P=74.) The opponent can do under-promotion to a piece of wildly
different value, though, and this was not corrected. It is now corrected
at game level (which is the only place it can happen).
---

diff --git a/changelog b/changelog
index 6431c94..081204f 100644
--- a/changelog
+++ b/changelog
@@ -112,5 +112,6 @@
           * Fix bug in Berolina e.p. capture that is actually non-capture
           * Fix Clear Hash option, which did not work at all
           * Fix addition of 6th & 7th-rank Pawn bonus when setting up position
+          * set promotion bonus on (under-)promotion to true piece value
           In addition it prints msec-accurate timing info.
 
diff --git a/fairymax.c b/fairymax.c
index bdb76e4..b236e4d 100644
--- a/fairymax.c
+++ b/fairymax.c
@@ -232,8 +232,9 @@ int k,q,l,e,ev,E,z,n;    /* (q,l)=window, e=current eval. score, E=e.p. sqr.*/
         if(z&S&&K-I)                           /* move pending: check legal*/
         {if(v+I&&x==K&y==L&gt==GT)             /*   if move found          */
          {Q=-e-i;O=F;LL=L;prom=gt;
-          if(b[y]-u&15)prom=b[y]-=PromPiece,   /* under-promotion, correct */
-           pl[u&31]--,pl[prom&31]++,Z+=PromPiece;/*piece & invalidate hash */
+          if(b[y]-u&15)prom=b[y]-=PromPiece,   /* (under-)promotion:       */
+           Q-=abs(w[prom&=31])-w[p]-6*S,       /*  correct piece & score & */
+           pl[u&31]--,pl[prom]++,Z+=PromPiece; /*  count & invalidate hash */
           a->D=99;a->V=0;                      /* lock game in hash as draw*/
           R-=i/FAC;                            /*** total captd material ***/
           Fifty = t|p<3?0:Fifty+1;