diff -r faec61c4901f -r 970748b9a73b src/game.h
--- a/src/game.h	Wed Mar 26 14:12:59 2014 +0100
+++ b/src/game.h	Wed Mar 26 14:53:15 2014 +0100
@@ -37,8 +37,9 @@
 extern "C" {
 #endif
 
-#define PIECE_MASK 0x0F
-#define COLOR_MASK 0xF0
+#define PIECE_MASK       0x0F
+#define COLOR_MASK       0x30
+#define ENPASSANT_THREAT 0x40
 
 #define WHITE 0x10
 #define BLACK 0x20
@@ -77,6 +78,8 @@
 } Move;
 
 #define POS_UNSPECIFIED UINT8_MAX
+#define mdst(b,m) b[m->torow][m->tofile]
+#define msrc(b,m) b[m->fromrow][m->fromfile]
 
 #define isidx(idx) ((uint8_t)idx < 8)