--- /dev/null
+/*
+ * MIT License
+ *
+ * Copyright (c) 2023 Wesley Aptekar-Cassels
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include "watch_utility.h"
+#include "solstice_face.h"
+
+// Find solstice or equinox time in JDE for a given year, via method from Meeus Ch 27
+static double calculate_solstice_equinox(uint16_t year, uint8_t k) {
+ double Y = ((double)year - 2000) / 1000;
+ double approx_terms[4][5] = {
+ {2451623.80984, 365242.37404, 0.05169, -0.00411, -0.00057}, // March equinox
+ {2451716.56767, 365241.62603, 0.00325, 0.00888, -0.00030}, // June solstice
+ {2451810.21715, 365242.01767, -0.11575, 0.00337, 0.00078}, // September equinox
+ {2451900.05952, 365242.74049, -0.06223, -0.00823, 0.00032}, // December solstice
+ };
+ double JDE0 = approx_terms[k][0] + Y * (approx_terms[k][1] + Y * (approx_terms[k][2] + Y * (approx_terms[k][3] + Y * approx_terms[k][4])));
+ double T = (JDE0 - 2451545.0) / 36525;
+ double W = 35999.373 * T - 2.47;
+ double dlambda = 1 + (0.0334 * cos(W * M_PI / 180.0)) + (0.0007 * cos(2 * W * M_PI / 180.0));
+ double correction_terms[25][3] = {
+ {485,324.96,1934.136},
+ {203,337.23,32964.467},
+ {199,342.08,20.186},
+ {182,27.85,445267.112},
+ {156,73.14,45036.886},
+ {136,171.52,22518.443},
+ {77,222.54,65928.934},
+ {74,296.72,3034.906},
+ {70,243.58,9037.513},
+ {58,119.81,33718.147},
+ {52,297.17,150.678},
+ {50,21.02,2281.226},
+ {45,247.54,29929.562},
+ {44,325.15,31555.956},
+ {29,60.93,4443.417},
+ {18,155.12,67555.328},
+ {17,288.79,4562.452},
+ {16,198.04,62894.029},
+ {14,199.76,31436.921},
+ {12,95.39,14577.848},
+ {12,287.11,31931.756},
+ {12,320.81,34777.259},
+ {9,227.73,1222.114},
+ {8,15.45,16859.074},
+ };
+ double S = 0;
+ for (int i = 0; i < 25; i++) {
+ S += correction_terms[i][0] * cos((correction_terms[i][1] + correction_terms[i][2] * T) * M_PI / 180.0);
+ }
+ double JDE = JDE0 + (0.00001 * S) / dlambda;
+
+ return JDE;
+}
+
+// Convert JDE to Gergorian datetime as per Meeus Ch 7
+static watch_date_time jde_to_date_time(double JDE) {
+ double tmp = JDE + 0.5;
+ double Z = floor(tmp);
+ double F = fmod(tmp, 1);
+ double A;
+ if (Z < 2299161) {
+ A = Z;
+ } else {
+ double alpha = floor((Z - 1867216.25) / 36524.25);
+ A = Z + 1 + alpha - floor(alpha / 4);
+ }
+ double B = A + 1524;
+ double C = floor((B - 122.1) / 365.25);
+ double D = floor(365.25 * C);
+ double E = floor((B - D) / 30.6001);
+ double day = B - D - floor(30.6001 * E) + F;
+ double month;
+ if (E < 14) {
+ month = E - 1;
+ } else {
+ month = E - 13;
+ }
+ double year;
+ if (month > 2) {
+ year = C - 4716;
+ } else {
+ year = C - 4715;
+ }
+
+ double hours = fmod(day, 1) * 24;
+ double minutes = fmod(hours, 1) * 60;
+ double seconds = fmod(minutes, 1) * 60;
+
+ watch_date_time result = {.unit = {
+ floor(seconds),
+ floor(minutes),
+ floor(hours),
+ floor(day),
+ floor(month),
+ floor(year - 2020)
+ }};
+
+ return result;
+}
+
+static void calculate_datetimes(solstice_state_t *state, movement_settings_t *settings) {
+ for (int i = 0; i < 4; i++) {
+ // TODO: handle DST changes
+ state->datetimes[i] = jde_to_date_time(calculate_solstice_equinox(2020 + state->year, i) + (movement_timezone_offsets[settings->bit.time_zone] / (60.0*24.0)));
+ }
+}
+
+void solstice_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) {
+ (void) settings;
+ (void) watch_face_index;
+ if (*context_ptr == NULL) {
+ *context_ptr = malloc(sizeof(solstice_state_t));
+ solstice_state_t *state = (solstice_state_t *)*context_ptr;
+
+ watch_date_time now = watch_rtc_get_date_time();
+ state->year = now.unit.year;
+ state->index = 0;
+ calculate_datetimes(state, settings);
+
+ uint32_t now_unix = watch_utility_date_time_to_unix_time(now, 0);
+ for (int i = 0; i < 4; i++) {
+ if (state->index == 0 && watch_utility_date_time_to_unix_time(state->datetimes[i], 0) > now_unix) {
+ state->index = i;
+ }
+ }
+ }
+}
+
+void solstice_face_activate(movement_settings_t *settings, void *context) {
+ (void) settings;
+ (void) context;
+}
+
+static void show_main_screen(solstice_state_t *state) {
+ char buf[11];
+ watch_date_time date_time = state->datetimes[state->index];
+ sprintf(buf, " %2d %2d%02d", date_time.unit.year + 20, date_time.unit.month, date_time.unit.day);
+ watch_display_string(buf, 0);
+}
+
+static void show_date_time(movement_settings_t *settings, solstice_state_t *state) {
+ char buf[11];
+ watch_date_time date_time = state->datetimes[state->index];
+ if (!settings->bit.clock_mode_24h) {
+ if (date_time.unit.hour < 12) {
+ watch_clear_indicator(WATCH_INDICATOR_PM);
+ } else {
+ watch_set_indicator(WATCH_INDICATOR_PM);
+ }
+ date_time.unit.hour %= 12;
+ if (date_time.unit.hour == 0) date_time.unit.hour = 12;
+ }
+ sprintf(buf, "%s%2d%2d%02d%02d", watch_utility_get_weekday(date_time), date_time.unit.day, date_time.unit.hour, date_time.unit.minute, date_time.unit.second);
+ watch_set_colon();
+ watch_display_string(buf, 0);
+}
+
+bool solstice_face_loop(movement_event_t event, movement_settings_t *settings, void *context) {
+ solstice_state_t *state = (solstice_state_t *)context;
+
+ switch (event.event_type) {
+ case EVENT_ALARM_LONG_PRESS:
+ show_date_time(settings, state);
+ break;
+ case EVENT_LIGHT_BUTTON_UP:
+ if (state->index == 0) {
+ if (state->year == 0) {
+ break;
+ }
+ state->year--;
+ state->index = 3;
+ calculate_datetimes(state, settings);
+ } else {
+ state->index--;
+ }
+ show_main_screen(state);
+ break;
+ case EVENT_ALARM_BUTTON_UP:
+ state->index++;
+ if (state->index > 3) {
+ if (state->year == 83) {
+ break;
+ }
+ state->year++;
+ state->index = 0;
+ calculate_datetimes(state, settings);
+ }
+ show_main_screen(state);
+ break;
+ case EVENT_ALARM_LONG_UP:
+ watch_clear_colon();
+ watch_clear_indicator(WATCH_INDICATOR_PM);
+ show_main_screen(state);
+ break;
+ case EVENT_ACTIVATE:
+ show_main_screen(state);
+ break;
+ case EVENT_TIMEOUT:
+ movement_move_to_face(0);
+ break;
+ default:
+ return movement_default_loop_handler(event, settings);
+ }
+
+ return true;
+}
+
+void solstice_face_resign(movement_settings_t *settings, void *context) {
+ (void) settings;
+ (void) context;
+}
+
--- /dev/null
+/*
+ * MIT License
+ *
+ * Copyright (c) 2023 Wesley Aptekar-Cassels
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef SOLSTICE_FACE_H_
+#define SOLSTICE_FACE_H_
+
+#include "movement.h"
+
+/*
+ * A face for telling the dates and times of solstices and equinoxes
+ *
+ * It shows the upcoming solstice or equinox by default. The upper right number
+ * is the year, and the bottom numbers are the date in MMDD format. Use the
+ * alarm / light buttons to go forwards / backwards in time. Long press the
+ * alarm button to show the time of the event, including what weekday it is on,
+ * in your local timezone (DST is not handled).
+ *
+ * Supports the years 2020 - 2083. The calculations are reasonably accurate for
+ * years between 1000 and 3000, but limitations in the sensor watch libraries
+ * (which could easily be worked around) prevent making use of that.
+ */
+
+typedef struct {
+ watch_date_time datetimes[4];
+ uint8_t year;
+ uint8_t index;
+} solstice_state_t;
+
+void solstice_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr);
+void solstice_face_activate(movement_settings_t *settings, void *context);
+bool solstice_face_loop(movement_event_t event, movement_settings_t *settings, void *context);
+void solstice_face_resign(movement_settings_t *settings, void *context);
+
+#define solstice_face ((const watch_face_t){ \
+ solstice_face_setup, \
+ solstice_face_activate, \
+ solstice_face_loop, \
+ solstice_face_resign, \
+ NULL, \
+})
+
+#endif // SOLSTICE_FACE_H_
+
projects / sensor-watch.git / commitdiff