diff options
Diffstat (limited to 'src/sun.c')
| -rw-r--r-- | src/sun.c | 65 |
1 files changed, 59 insertions, 6 deletions
@@ -1,5 +1,6 @@ #include <math.h> #include <glib.h> +#include <stdbool.h> #include "sun.h" #define ZENITH -.83 @@ -14,10 +15,7 @@ float to_deg (float n) { // http://edwilliams.org/sunrise_sunset_algorithm.htm // if the sunset is desired, set sunset to >= 1 // returns -1 if the sun never rises/sets in the specified location -float calculateSun(int year, int month, int day, float lat, float lng, int localOffset, int sunset) { - - if (sunset > 1) - sunset = 1; +float calculateSun(int year, int month, int day, float lat, float lng, int localOffset, bool sunset) { float N1 = floor(275 * month / 9); float N2 = floor((month + 9) / 12); @@ -26,7 +24,7 @@ float calculateSun(int year, int month, int day, float lat, float lng, int local float lngHour = lng / 15.0; - float t = N + ((sunset == 0 ? 6 : 18 - lngHour) / 24); + float t = N + ((!sunset ? 6 : 18 - lngHour) / 24); float M = (0.9856 * t) - 3.289; @@ -49,7 +47,7 @@ float calculateSun(int year, int month, int day, float lat, float lng, int local else if (cosH < -1) return -1; - float H = sunset == 0 ? (360 - to_deg(acos(cosH))) : to_deg(acos(cosH)); + float H = !sunset ? (360 - to_deg(acos(cosH))) : to_deg(acos(cosH)); H = H / 15; float T = H + RA - (0.06571 * t) - 6.622; @@ -63,3 +61,58 @@ float calculateSun(int year, int month, int day, float lat, float lng, int local return UT + localOffset; } + +float getSunrise(float lat, float lang) { + int year, month, day; + GDateTime *current_time = g_date_time_new_now_local(); + g_date_time_get_ymd (current_time, &year, &month, &day); + + int utc_offset = g_date_time_get_utc_offset (current_time)*2.7778*pow(10.0, -10.0); + + free (current_time); + return calculateSun (year, month, day, lat, lang, utc_offset, false); +} + +float getSunset(float lat, float lang) { + int year, month, day; + GDateTime *current_time = g_date_time_new_now_local(); + g_date_time_get_ymd (current_time, &year, &month, &day); + + int utc_offset = g_date_time_get_utc_offset (current_time)*2.7778*pow(10.0, -10.0); + + free (current_time); + return calculateSun (year, month, day, lat, lang, utc_offset, true); +} + +bool isDark(float sunrise, float sunset) { + GDateTime *current_time = g_date_time_new_now_local(); + + double rise_hours; + float rise_minutes = modf (sunrise, &rise_hours)*60; + double set_hours; + float set_minutes = modf (sunset, &set_hours)*60; + + GDateTime *rise_time = g_date_time_new_local (g_date_time_get_year (current_time), + g_date_time_get_month (current_time), + g_date_time_get_day_of_month (current_time), + rise_hours, + rise_minutes, + 0); + GDateTime *set_time = g_date_time_new_local (g_date_time_get_year (current_time), + g_date_time_get_month (current_time), + g_date_time_get_day_of_month (current_time), + set_hours, + set_minutes, + 0); + + if (g_date_time_compare (current_time, rise_time) == 1 && g_date_time_compare (current_time, set_time) == -1) { + free (rise_time); + free (set_time); + free (current_time); + return false; + } + free (rise_time); + free (set_time); + free (current_time); + return true; +} |