diff options
| -rw-r--r-- | src/libred.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/src/libred.h b/src/libred.h index d04ffb6..0bccd84 100644 --- a/src/libred.h +++ b/src/libred.h @@ -45,6 +45,11 @@ */ #define LIBRED_SOLAR_ELEVATION_ASTRONOMICAL_DUSK_DAWN (-18.0) +/** + * The Sun's elevation at amateur astronomical dusk and amateur astronomical dawn, measured in degrees. + */ +#define LIBRED_SOLAR_ELEVATION_AMATEUR_ASTRONOMICAL_DUSK_DAWN (-15.0) + /** * Test whether it is twilight. @@ -78,6 +83,14 @@ */ #define LIBRED_IS_ASTRONOMICAL_TWILIGHT(ELEV) ((-18.0 <= (ELEV)) && ((ELEV) <= -32.0 / 60.0)) +/** + * Test whether it is amateur astronomical twilight. + * + * @param ELEV:double The current elevation. + * @return 1 if is astronomical twilight, 0 otherwise. + */ +#define LIBRED_IS_AMATEUR_ASTRONOMICAL_TWILIGHT(ELEV) ((-18.0 <= (ELEV)) && ((ELEV) <= -15.0)) + /** * Calculates the Sun's elevation as apparent |