+/* fundamental game speed values */
+#define ONE_SECOND_DELAY 1000 /* delay value for one second */
+#define GAME_FRAME_DELAY 20 /* frame delay in milliseconds */
+#define FFWD_FRAME_DELAY 10 /* 200% speed for fast forward */
+#define FRAMES_PER_SECOND (ONE_SECOND_DELAY / GAME_FRAME_DELAY)