Allow castling with any original corner piece

[fairymax.git] / fairymax.c

diff --git a/fairymax.c b/fairymax.c
index c166ee1..6ccbc9c 100644 (file)
--- a/fairymax.c
+++ b/fairymax.c
@@ -240,7 +240,7 @@ int k,q,l,e,E,z,n;      /* (q,l)=window, e=current eval. score, E=e.p. sqr.*/
       s=t;\r
       if(flag&15^4|u&32||                      /* no double or moved before*/\r
          p>2&&                                 /* no P & no lateral K move,*/\r
-         (b[G=r<0?x&~15:BW-1|x&112]-k-6        /* no virgin R in corner G, */\r
+         ((b[G=r<0?x&~15:BW-1|x&112]^32)<33    /* no virgin R in corner G, */\r
          ||b[G^1]|b[G^2]|b[FF=r<0?G+3:G-2])    /* no 2 empty sq. next to R */\r
         )t+=flag&4;                            /* fake capt. for nonsliding*/\r
       else F=y;                                /* enable e.p.              */\r
@@ -776,23 +776,16 @@ int main(int argc, char **argv)
                                             else b[m]=(m&0x70)==0x10?18:50,\r
                                                  Q+=w[2];\r
                                             break;\r
-                                        case 3: // can castle, normally King\r
-                                            b[m]=3+color+32;\r
-                                            if(m==BW>>1        && color==BLACK ||\r
-                                               m==0x70+(BW>>1) && color==WHITE)\r
-                                                b[m] -= 32;\r
-                                            break;\r
-                                        case 6: // can castle, normally Rook\r
-                                            b[m]=6+color+32;\r
-                                            if((m==0x00 || m==BW-1   ) && color==BLACK ||\r
-                                               (m==0x70 || m==0x6F+BW) && color==WHITE)\r
-                                                b[m] -= 32;\r
-                                            Q+=w[6]; R+=w[6]/FAC;\r
-                                            break;\r
                                         default:\r
-                                            b[m]=p+color;\r
-                                            Q+=w[p]; R+=w[p]/FAC;\r
-                                                   case 0: // undefined piece, ignore\r
+                                            b[m]=p+color+32; // assume non-virgin\r
+                                            if(w[p]<0) { // Royal piece on original square: virgin
+                                               if(color==BLACK && m<0x10 && p==oo[m+16] ||\r
+                                                   color==WHITE && m>0x6F && p==oo[m-0x70]) b[m] -= 32;
+                                           } else { Q+=w[p]; R+=w[p]/FAC; }
+                                            if((m==0x00 || m==BW-1   ) && color==BLACK && p==oo[m+16] ||\r
+                                               (m==0x70 || m==0x6F+BW) && color==WHITE && p==oo[m-0x70])\r
+                                                b[m] &= ~32; // corner piece as in original setup: virgin\r
+                                       case 0: // undefined piece, ignore\r
                                             break;\r
                                         }\r
                                         pl[BLACK+WHITE-color]++;\r