X-Git-Url: https://git.artsoft.org/?a=blobdiff_plain;f=src%2Flibgame%2Fsystem.h;h=f39eb1b1a546d4ab450160a008819f5562a0a2f3;hb=1c636a51bb573815d24a27dcc20b3283d89d1b8b;hp=086f01c2aa11a5a73627878f7fca9f54c1831e82;hpb=b764179e9f5cbe4ebdfc1b76b9947c2660e34b07;p=rocksndiamonds.git

diff --git a/src/libgame/system.h b/src/libgame/system.h
index 086f01c2..f39eb1b1 100644
--- a/src/libgame/system.h
+++ b/src/libgame/system.h
@@ -116,6 +116,11 @@
 				 (x) == MV_RIGHT ? MV_BIT_RIGHT :	\
 				 (x) == MV_UP    ? MV_BIT_UP    : MV_BIT_DOWN)
 
+#define MV_DIR_OPPOSITE(x)	((x) == MV_LEFT  ? MV_RIGHT :		\
+				 (x) == MV_RIGHT ? MV_LEFT  :		\
+				 (x) == MV_UP    ? MV_DOWN  :		\
+				 (x) == MV_DOWN  ? MV_UP    : MV_NO_MOVING)
+
 
 /* values for animation mode (frame order and direction) */
 #define ANIM_NONE		0