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-rw-r--r--src/main.c71
-rw-r--r--src/meson.build15
-rw-r--r--src/sun.c156
-rw-r--r--src/sun.h2
4 files changed, 244 insertions, 0 deletions
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..34f528a
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,71 @@
+/* main.c
+ *
+ * Copyright 2024 Unknown
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3 of the License only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "config.h"
+#include "sun.h"
+#include<math.h>
+
+#include <glib.h>
+#include <stdlib.h>
+
+gint
+main (gint argc,
+ gchar *argv[])
+{
+ g_autoptr(GOptionContext) context = NULL;
+ g_autoptr(GError) error = NULL;
+ gboolean version = FALSE;
+ GOptionEntry main_entries[] = {
+ { "version", 0, 0, G_OPTION_ARG_NONE, &version, "Show program version" },
+ { NULL }
+ };
+
+ context = g_option_context_new ("- my command line tool");
+ g_option_context_add_main_entries (context, main_entries, NULL);
+
+ if (!g_option_context_parse (context, &argc, &argv, &error))
+ {
+ g_printerr ("%s\n", error->message);
+ return EXIT_FAILURE;
+ }
+
+ if (version)
+ {
+ g_printerr ("%s\n", PACKAGE_VERSION);
+ return EXIT_SUCCESS;
+ }
+
+ int year = 2024, month = 5, day = 28;
+ double latitude = 51.01;
+ double longitude = 7.563;
+
+ float localT = calculateSunrise(year, month, day, latitude, longitude, 2);
+ double hours;
+ float minutes = modf(localT,&hours)*60;
+ g_print("Sunrise: %.0f:%.0f\n",hours,minutes);
+
+ float sunsetT = calculateSunset(year, month, day, latitude, longitude, 2);
+ double sunHours;
+ float sunMinutes = modf(sunsetT,&sunHours)*60;
+ g_print("Sunset: %.0f:%.0f\n",sunHours,sunMinutes);
+
+ return 0;
+
+ return EXIT_SUCCESS;
+}
diff --git a/src/meson.build b/src/meson.build
new file mode 100644
index 0000000..4848423
--- /dev/null
+++ b/src/meson.build
@@ -0,0 +1,15 @@
+autodarkmode_sources = [
+ 'main.c',
+ 'sun.c'
+]
+
+autodarkmode_deps = [
+ dependency('glib-2.0'),
+]
+
+executable('autodarkmode', autodarkmode_sources,
+ dependencies: autodarkmode_deps,
+ install: true,
+ link_args: '-lm',
+)
+
diff --git a/src/sun.c b/src/sun.c
new file mode 100644
index 0000000..f08dfd8
--- /dev/null
+++ b/src/sun.c
@@ -0,0 +1,156 @@
+#include <math.h>
+#include <glib.h>
+#define PI 3.1415926
+#define ZENITH -.83
+
+float calculateSunrise(int year,int month,int day,float lat, float lng,int localOffset) {
+ /*
+ localOffset will be <0 for western hemisphere and >0 for eastern hemisphere
+ daylightSavings should be 1 if it is in effect during the summer otherwise it should be 0
+ */
+ //1. first calculate the day of the year
+ float N1 = floor(275 * month / 9);
+ float N2 = floor((month + 9) / 12);
+ float N3 = (1 + floor((year - 4 * floor(year / 4) + 2) / 3));
+ float N = N1 - (N2 * N3) + day - 30;
+
+ //2. convert the longitude to hour value and calculate an approximate time
+ float lngHour = lng / 15.0;
+ float t = N + ((6 - lngHour) / 24);
+
+ //3. calculate the Sun's mean anomaly
+ float M = (0.9856 * t) - 3.289;
+
+ //4. calculate the Sun's true longitude
+ float L = fmod(M + (1.916 * sin((PI/180)*M)) + (0.020 * sin(2 *(PI/180) * M)) + 282.634,360.0);
+
+ if ( L < 0 )
+ L = L+360;
+ else if ( L > 360)
+ L = L-360;
+
+ //5a. calculate the Sun's right ascension
+ float RA = fmod(180/PI*atan(0.91764 * tan((PI/180)*L)),360.0);
+
+ if ( RA < 0 )
+ RA = RA+360;
+ else if ( RA > 360)
+ RA = RA-360;
+
+ //5b. right ascension value needs to be in the same quadrant as L
+ float Lquadrant = floor( L/90) * 90;
+ float RAquadrant = floor(RA/90) * 90;
+ RA = RA + (Lquadrant - RAquadrant);
+
+ //5c. right ascension value needs to be converted into hours
+ RA = RA / 15;
+
+ //6. calculate the Sun's declination
+ float sinDec = 0.39782 * sin((PI/180)*L);
+ float cosDec = cos(asin(sinDec));
+
+ //7a. calculate the Sun's local hour angle
+ float cosH = (sin((PI/180)*ZENITH) - (sinDec * sin((PI/180)*lat))) / (cosDec * cos((PI/180)*lat));
+
+ if (cosH > 1)
+ g_print("Never rising\n");
+ else if (cosH < -1)
+ g_print("Never setting\n");
+
+ //7b. finish calculating H and convert into hours
+ float H = 360 - (180/PI)*acos(cosH); // if if rising time is desired:
+
+ H = H / 15;
+
+ //8. calculate local mean time of rising/setting
+ float T = H + RA - (0.06571 * t) - 6.622;
+
+ //9. adjust back to UTC
+ float UT = fmod(T - lngHour,24.0);
+
+ if ( UT < 0 )
+ UT = UT+24;
+ else if (UT > 24)
+ UT = UT-24;
+
+ //10. convert UT value to local time zone of latitude/longitude
+ return UT + localOffset;
+
+ }
+
+float calculateSunset(int year,int month,int day,float lat, float lng,int localOffset) {
+ /*
+ localOffset will be <0 for western hemisphere and >0 for eastern hemisphere
+ daylightSavings should be 1 if it is in effect during the summer otherwise it should be 0
+ */
+ //1. first calculate the day of the year
+ float N1 = floor(275 * month / 9);
+ float N2 = floor((month + 9) / 12);
+ float N3 = (1 + floor((year - 4 * floor(year / 4) + 2) / 3));
+ float N = N1 - (N2 * N3) + day - 30;
+
+ //2. convert the longitude to hour value and calculate an approximate time
+ float lngHour = lng / 15.0;
+
+ float t = N + ((18 - lngHour) / 24); //if setting time is desired:
+
+ //3. calculate the Sun's mean anomaly
+ float M = (0.9856 * t) - 3.289;
+
+ //4. calculate the Sun's true longitude
+ float L = fmod(M + (1.916 * sin((PI/180)*M)) + (0.020 * sin(2 *(PI/180) * M)) + 282.634,360.0);
+
+ if ( L < 0 )
+ L = L+360;
+ else if ( L > 360)
+ L = L-360;
+
+ //5a. calculate the Sun's right ascension
+ float RA = fmod(180/PI*atan(0.91764 * tan((PI/180)*L)),360.0);
+
+ if ( RA < 0 )
+ RA = RA+360;
+ else if ( RA > 360)
+ RA = RA-360;
+
+ //5b. right ascension value needs to be in the same quadrant as L
+ float Lquadrant = floor( L/90) * 90;
+ float RAquadrant = floor(RA/90) * 90;
+ RA = RA + (Lquadrant - RAquadrant);
+
+ //5c. right ascension value needs to be converted into hours
+ RA = RA / 15;
+
+ //6. calculate the Sun's declination
+ float sinDec = 0.39782 * sin((PI/180)*L);
+ float cosDec = cos(asin(sinDec));
+
+ //7a. calculate the Sun's local hour angle
+ float cosH = (sin((PI/180)*ZENITH) - (sinDec * sin((PI/180)*lat))) / (cosDec * cos((PI/180)*lat));
+
+ if (cosH > 1)
+ g_print("Never rising\n");
+ else if (cosH < -1)
+ g_print("Never setting\n");
+
+
+ //7b. finish calculating H and convert into hours
+
+ float H = (180/PI)*acos(cosH); // if setting time is desired:
+ H = H / 15;
+
+ //8. calculate local mean time of rising/setting
+ float T = H + RA - (0.06571 * t) - 6.622;
+
+ //9. adjust back to UTC
+ float UT = fmod(T - lngHour,24.0);
+
+ if ( UT < 0 )
+ UT = UT+24;
+ else if (UT > 24)
+ UT = UT-24;
+
+ //10. convert UT value to local time zone of latitude/longitude
+ return UT + localOffset;
+
+}
diff --git a/src/sun.h b/src/sun.h
new file mode 100644
index 0000000..0eeb187
--- /dev/null
+++ b/src/sun.h
@@ -0,0 +1,2 @@
+float calculateSunrise(int year,int month,int day,float lat, float lng,int localOffset);
+float calculateSunset(int year,int month,int day,float lat, float lng,int localOffset);
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-16 16:35:10 +0000