#define FPS 60
-#define NSEC_PER_SEC 1e9
+#define NSEC_PER_SEC 1000000000
#define timespecsub(a, b, result) \
do { \
(result)->tv_nsec = (a)->tv_nsec - (b)->tv_nsec; \
if ((result)->tv_nsec < 0) { \
--(result)->tv_sec; \
- (result)->tv_nsec += 1e9; \
+ (result)->tv_nsec += 1000000000; \
} \
} while(0)