Raffael Mancini
ff3c8a72fc
Full implementation of the local solar time complication using the pveducation.org formula set (LSTM, B, EoT, TC, LST, HRA). EoT and TC are cached by day-of-year and recomputed once at midnight rollover. Three display modes cycle with the Alarm button: SO HH:MM:SS — Local Solar Time nO HH:MM — Solar Noon in local clock time Hr ±DDD — Hour Angle in degrees Location is read from location.u32 on the filesystem. In the simulator the browser lat/lon globals are written to location.u32 on activation if not already set, fixing the "no Loc" issue in the emulator.
228 lines
8.1 KiB
C
228 lines
8.1 KiB
C
/*
|
|
* MIT License
|
|
*
|
|
* Copyright (c) 2025 Raffael Mancini
|
|
*
|
|
* 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.
|
|
*
|
|
* Solar time formulas follow the notation from:
|
|
* https://www.pveducation.org/pvcdrom/properties-of-sunlight/solar-time
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <math.h>
|
|
#include "local_solar_time_face.h"
|
|
#include "watch.h"
|
|
#include "watch_utility.h"
|
|
#include "filesystem.h"
|
|
|
|
#if __EMSCRIPTEN__
|
|
#include <emscripten.h>
|
|
#endif
|
|
|
|
#ifndef M_PI
|
|
#define M_PI 3.14159265358979323846f
|
|
#endif
|
|
|
|
/* ---------------------------------------------------------------------------
|
|
* Solar time math (pveducation.org notation)
|
|
* ---------------------------------------------------------------------------
|
|
*
|
|
* LSTM = 15 * ΔTUTC [degrees]
|
|
* B = (360 / 365) * (d - 81) [degrees] d = day-of-year
|
|
* EoT = 9.87*sin(2B) - 7.53*cos(B)
|
|
* - 1.5*sin(B) [minutes]
|
|
* TC = 4 * (Longitude - LSTM) + EoT [minutes]
|
|
* LST = LT + TC/60 [hours]
|
|
* HRA = 15 * (LST - 12) [degrees]
|
|
* ---------------------------------------------------------------------------
|
|
*/
|
|
|
|
static movement_location_t _load_location(void) {
|
|
movement_location_t loc = {0};
|
|
filesystem_read_file("location.u32", (char *)&loc.reg, sizeof(loc.reg));
|
|
return loc;
|
|
}
|
|
|
|
/* Compute and cache EoT and TC. Call when d != state->last_calc_d. */
|
|
static void _compute_daily(local_solar_time_state_t *state, uint16_t d) {
|
|
/* LSTM — movement_get_current_timezone_offset() returns seconds from UTC */
|
|
float delta_T_UTC = (float)movement_get_current_timezone_offset() / 3600.0f;
|
|
float LSTM = 15.0f * delta_T_UTC;
|
|
|
|
movement_location_t loc = _load_location();
|
|
float longitude = (float)(int16_t)loc.bit.longitude / 100.0f;
|
|
|
|
/* B in radians for sinf/cosf */
|
|
float B = (360.0f / 365.0f) * ((float)d - 81.0f) * ((float)M_PI / 180.0f);
|
|
|
|
state->EoT = 9.87f * sinf(2.0f * B) - 7.53f * cosf(B) - 1.5f * sinf(B);
|
|
state->TC = 4.0f * (longitude - LSTM) + state->EoT;
|
|
state->last_calc_d = d;
|
|
}
|
|
|
|
/* Recompute if the day-of-year has rolled over. Returns current d. */
|
|
static uint16_t _maybe_recompute(local_solar_time_state_t *state, watch_date_time_t dt) {
|
|
uint16_t d = watch_utility_days_since_new_year(
|
|
(uint16_t)(dt.unit.year + WATCH_RTC_REFERENCE_YEAR),
|
|
dt.unit.month,
|
|
dt.unit.day
|
|
);
|
|
if (d != state->last_calc_d && _load_location().reg != 0) {
|
|
_compute_daily(state, d);
|
|
}
|
|
return d;
|
|
}
|
|
|
|
/* LST as total seconds since midnight (0..86399).
|
|
* LST = LT + TC/60 => in seconds: LT_sec + TC*60 */
|
|
static int32_t _lst_seconds(watch_date_time_t dt, float TC) {
|
|
int32_t lt = (int32_t)dt.unit.hour * 3600
|
|
+ (int32_t)dt.unit.minute * 60
|
|
+ (int32_t)dt.unit.second;
|
|
int32_t tc = (int32_t)(TC * 60.0f);
|
|
return ((lt + tc) % 86400 + 86400) % 86400;
|
|
}
|
|
|
|
static void _update_display(local_solar_time_state_t *state, watch_date_time_t dt) {
|
|
char buf[14];
|
|
|
|
if (_load_location().reg == 0) {
|
|
watch_display_text(WATCH_POSITION_FULL, "SO no Loc");
|
|
return;
|
|
}
|
|
|
|
switch (state->mode) {
|
|
|
|
case LOCAL_SOLAR_TIME_MODE_LST: {
|
|
int32_t s = _lst_seconds(dt, state->TC);
|
|
sprintf(buf, "SO %02d%02d%02d",
|
|
(int)(s / 3600), (int)((s % 3600) / 60), (int)(s % 60));
|
|
watch_set_colon();
|
|
break;
|
|
}
|
|
|
|
case LOCAL_SOLAR_TIME_MODE_NOON: {
|
|
/* Solar noon: moment when LST = 12:00 → LT_noon = 12h - TC/60 */
|
|
int32_t s = (int32_t)(( 12.0f - state->TC / 60.0f) * 3600.0f);
|
|
s = ((s % 86400) + 86400) % 86400;
|
|
sprintf(buf, "nO %02d%02d ", (int)(s / 3600), (int)((s % 3600) / 60));
|
|
watch_set_colon();
|
|
break;
|
|
}
|
|
|
|
case LOCAL_SOLAR_TIME_MODE_HRA: {
|
|
/* HRA = 15 * (LST - 12); negative = morning, positive = afternoon */
|
|
int32_t s = _lst_seconds(dt, state->TC);
|
|
int16_t hra = (int16_t)roundf(15.0f * ((float)s / 3600.0f - 12.0f));
|
|
sprintf(buf, "Hr %+4d ", (int)hra);
|
|
watch_clear_colon();
|
|
break;
|
|
}
|
|
|
|
default:
|
|
return;
|
|
}
|
|
|
|
watch_display_text(WATCH_POSITION_FULL, buf);
|
|
}
|
|
|
|
/* ---- Movement callbacks -------------------------------------------------- */
|
|
|
|
void local_solar_time_face_setup(uint8_t watch_face_index, void **context_ptr) {
|
|
(void)watch_face_index;
|
|
if (*context_ptr == NULL) {
|
|
*context_ptr = malloc(sizeof(local_solar_time_state_t));
|
|
memset(*context_ptr, 0, sizeof(local_solar_time_state_t));
|
|
/* last_calc_d == 0 guarantees recomputation on first tick */
|
|
}
|
|
}
|
|
|
|
void local_solar_time_face_activate(void *context) {
|
|
local_solar_time_state_t *state = (local_solar_time_state_t *)context;
|
|
|
|
#if __EMSCRIPTEN__
|
|
/* In the simulator the browser exposes lat/lon as JS globals.
|
|
* Write them to location.u32 if not already set. */
|
|
int16_t browser_lat = EM_ASM_INT({ return lat; });
|
|
int16_t browser_lon = EM_ASM_INT({ return lon; });
|
|
if (browser_lat || browser_lon) {
|
|
movement_location_t browser_loc = {0};
|
|
filesystem_read_file("location.u32", (char *)&browser_loc.reg, sizeof(browser_loc.reg));
|
|
if (browser_loc.reg == 0) {
|
|
browser_loc.bit.latitude = browser_lat;
|
|
browser_loc.bit.longitude = browser_lon;
|
|
filesystem_write_file("location.u32", (char *)&browser_loc.reg, sizeof(browser_loc.reg));
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* Force recompute on activation: timezone or location may have changed */
|
|
state->last_calc_d = 0;
|
|
watch_date_time_t dt = movement_get_local_date_time();
|
|
_maybe_recompute(state, dt);
|
|
}
|
|
|
|
bool local_solar_time_face_loop(movement_event_t event, void *context) {
|
|
local_solar_time_state_t *state = (local_solar_time_state_t *)context;
|
|
|
|
switch (event.event_type) {
|
|
case EVENT_ACTIVATE:
|
|
case EVENT_TICK: {
|
|
watch_date_time_t dt = movement_get_local_date_time();
|
|
_maybe_recompute(state, dt);
|
|
_update_display(state, dt);
|
|
break;
|
|
}
|
|
|
|
case EVENT_ALARM_BUTTON_UP:
|
|
state->mode = (local_solar_time_mode_t)((state->mode + 1) % LOCAL_SOLAR_TIME_NUM_MODES);
|
|
{
|
|
watch_date_time_t dt = movement_get_local_date_time();
|
|
_update_display(state, dt);
|
|
}
|
|
break;
|
|
|
|
case EVENT_LOW_ENERGY_UPDATE: {
|
|
if (!watch_sleep_animation_is_running()) watch_start_sleep_animation(1000);
|
|
watch_date_time_t dt = movement_get_local_date_time();
|
|
_maybe_recompute(state, dt);
|
|
_update_display(state, dt);
|
|
break;
|
|
}
|
|
|
|
case EVENT_TIMEOUT:
|
|
state->mode = LOCAL_SOLAR_TIME_MODE_LST;
|
|
if (_load_location().reg == 0) movement_move_to_face(0);
|
|
break;
|
|
|
|
default:
|
|
return movement_default_loop_handler(event);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void local_solar_time_face_resign(void *context) {
|
|
local_solar_time_state_t *state = (local_solar_time_state_t *)context;
|
|
state->mode = LOCAL_SOLAR_TIME_MODE_LST;
|
|
watch_clear_colon();
|
|
}
|