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| author | Mattias Andrée <maandree@kth.se> | 2016-07-07 09:47:07 +0200 |
|---|---|---|
| committer | Mattias Andrée <maandree@kth.se> | 2016-07-07 09:47:07 +0200 |
| commit | 3716996e47d32ad89c13fbd9c268da33df011c38 (patch) | |
| tree | a064ae00ace272f5f678dd2ccd601701736b112e | |
| parent | Fix division of twilights and sunset/sunrise (diff) | |
| download | libred-3716996e47d32ad89c13fbd9c268da33df011c38.tar.gz libred-3716996e47d32ad89c13fbd9c268da33df011c38.tar.bz2 libred-3716996e47d32ad89c13fbd9c268da33df011c38.tar.xz | |
Add amateur astronomical twilight
Signed-off-by: Mattias Andrée <maandree@kth.se>
| -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 |