fixed small bug in preprocessor macro

diff --git a/src/libgame/system.h b/src/libgame/system.h
index 88df586da83d553995800bd2767552197b33418e..6ed27de2c5a01fe529940329553dd2751eda7dcb 100644 (file)
--- a/src/libgame/system.h
+++ b/src/libgame/system.h
@@ -476,9 +476,9 @@
                                                GRID_REAL_HEIGHT),      \
                                            MAX_GRID_YSIZE)
 
-#define DEFAULT_GRID_XSIZE(n)          (n == 0 ? DEFAULT_GRID_XSIZE_0 : \
+#define DEFAULT_GRID_XSIZE(n)          ((n) == 0 ? DEFAULT_GRID_XSIZE_0 : \
                                         DEFAULT_GRID_XSIZE_1)
-#define DEFAULT_GRID_YSIZE(n)          (n == 0 ? DEFAULT_GRID_YSIZE_0 : \
+#define DEFAULT_GRID_YSIZE(n)          ((n) == 0 ? DEFAULT_GRID_YSIZE_0 : \
                                         DEFAULT_GRID_YSIZE_1)
 
 #define GRID_ACTIVE_NR()               (video.screen_width >   \