Fix promotion bonus

In its search Fairy-Max always promotes to 'Queen' ad 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..e8a3654 100644 (file)
--- 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
+          * Adapt score by true piece value in case of (under-)promotion
           In addition it prints msec-accurate timing info.
 

diff --git a/fairymax.c b/fairymax.c
index 15a5ce5..6f420ae 100644 (file)
--- a/fairymax.c
+++ b/fairymax.c
@@ -231,8 +231,9 @@ int k,q,l,e,E,z,n;      /* (q,l)=window, e=current eval. score, E=e.p. sqr.*/
         if(z&S&&K-I)                           /* move pending: check legal*/\r
         {if(v+I&&x==K&y==L&gt==GT)             /*   if move found          */\r
          {Q=-e-i;O=F;LL=L;prom=gt;\r
-          if(b[y]-u&15)prom=b[y]-=PromPiece,   /* under-promotion, correct */\r
-                       Z+=PromPiece;           /*  piece & invalidate hash */\r
+          if(b[y]-u&15)prom=b[y]-=PromPiece,   /* (under-)promotion:       */\r
+           Q-=abs(w[prom&=15])-w[p]-6*S,       /*  correct piece & score & */\r
+                       Z+=PromPiece;           /*  invalidate hash         */\r
           a->D=99;a->V=0;                      /* lock game in hash as draw*/\r
           R-=i/FAC;                            /*** total captd material ***/\r
           Fifty = t|p<3?0:Fifty+1;\r
@@ -582,7 +583,7 @@ int main(int argc, char **argv)
                             printf("move ");\r
                             printf("%c%c%c%c",'a'+(K&15),'0'+BH-(K>>4),\r
                                           'a'+(L&15),'0'+BH-(L>>4));\r
-                           if(prom)printf("%c",piecename[prom&15]+'a'-1);\r
+                           if(prom)printf("%c",piecename[prom]+'a'-1);\r
                             printf("\n");\r
 \r
                             /* time-control accounting */\r