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#include "object_tracker.h"
#include "common/geodetic/geodetic_coordinates.h"
#include "common/utils.h"
#include "logger.h"
#include "common/tracking/tle.h"
#include <cfloat>
namespace satdump
{
void ObjectTracker::backend_run()
{
while (backend_should_run)
{
std::this_thread::sleep_for(std::chrono::milliseconds(50));
if (!has_tle)
continue;
general_mutex.lock();
double current_time = getTime();
if (tracking_mode == TRACKING_HORIZONS)
{
if (current_time > last_horizons_fetch_time + 3600)
{
loadHorizons(current_time);
updateNextPass(current_time);
backend_needs_update = false;
}
if (horizons_data.size() > 0)
{
// size_t iter = 0;
// for (size_t i = 0; i < horizons_data.size(); i++)
// if (horizons_data[i].timestamp < current_time)
// iter = i;
if (current_time > next_los_time)
updateNextPass(current_time);
horizons_interpolate(current_time, &sat_current_pos.az, &sat_current_pos.el);
}
}
else if (tracking_mode == TRACKING_SATELLITE)
{
if (satellite_object != nullptr)
{
predict_orbit(satellite_object, &satellite_orbit, predict_to_julian_double(current_time));
predict_observe_orbit(satellite_observer_station, &satellite_orbit, &satellite_observation_pos);
if (current_time > next_los_time)
updateNextPass(current_time);
sat_current_pos.az = satellite_observation_pos.azimuth * RAD_TO_DEG;
sat_current_pos.el = satellite_observation_pos.elevation * RAD_TO_DEG;
}
}
// Update
if (backend_needs_update)
{
logger->trace("Updating elements...");
if (tracking_mode == TRACKING_HORIZONS)
{
loadHorizons(current_time);
updateNextPass(current_time);
}
else if (tracking_mode == TRACKING_SATELLITE)
{
if (satellite_object != nullptr)
predict_destroy_orbital_elements(satellite_object);
auto &tle = (*general_tle_registry)[current_satellite_id];
satellite_object = predict_parse_tle(tle.line1.c_str(), tle.line2.c_str());
updateNextPass(current_time);
}
backend_needs_update = false;
}
general_mutex.unlock();
}
}
void ObjectTracker::updateNextPass(double current_time)
{
upcoming_passes_mtx.lock();
logger->trace("Update pass trajectory...");
upcoming_pass_points.clear();
next_aos_time = 0;
next_los_time = 0;
northbound_cross = false;
southbound_cross = false;
if (tracking_mode == TRACKING_HORIZONS)
{
if (horizons_data.size() == 0)
{
upcoming_passes_mtx.unlock();
return;
}
int iter = 0;
for (int i = 0; i < (int)horizons_data.size(); i++)
if (horizons_data[i].timestamp < current_time)
iter = i;
if (horizons_data[iter].el > 0) // Already got AOS
{
next_aos_time = current_time;
for (int i = iter - 1; i >= 0; i--) // Attempt to find previous AOS
{
if (horizons_data[i].el <= 0)
{
next_aos_time = horizons_data[i].timestamp;
sat_next_aos_pos.az = horizons_data[i].az;
sat_next_aos_pos.el = 0;
break;
}
}
for (int i = iter; i < (int)horizons_data.size(); i++) // Find LOS
{
if (horizons_data[i].el <= 0)
{
next_los_time = horizons_data[i].timestamp;
break;
}
}
}
else
{
int aos_iter = 0;
for (int i = iter; i < (int)horizons_data.size(); i++) // Find AOS
{
if (horizons_data[i].el > 0)
{
next_aos_time = horizons_data[i].timestamp;
sat_next_aos_pos.az = horizons_data[i].az;
sat_next_aos_pos.el = 0;
aos_iter = i;
break;
}
}
if (next_aos_time != 0)
{
for (int i = aos_iter; i < (int)horizons_data.size(); i++) // Find LOS
{
if (horizons_data[i].el <= 0)
{
next_los_time = horizons_data[i].timestamp;
break;
}
}
}
}
if (/*is_gui &&*/ next_aos_time != 0 && next_los_time != 0)
{
double time_step = abs(next_los_time - next_aos_time) / 50.0;
for (double ctime = next_aos_time; ctime <= next_los_time; ctime += time_step)
{
int iter = 0;
for (int i = 0; i < (int)horizons_data.size(); i++)
if (horizons_data[i].timestamp < ctime)
iter = i;
upcoming_pass_points.push_back({horizons_data[iter].az, horizons_data[iter].el});
}
}
}
else if (tracking_mode == TRACKING_SATELLITE)
{
if (predict_is_geosynchronous(satellite_object))
{
next_aos_time = 0;
next_los_time = DBL_MAX;
upcoming_passes_mtx.unlock();
return;
}
// Get next LOS
predict_observation next_aos, next_los;
next_aos = next_los = predict_next_los(satellite_observer_station, satellite_object, predict_to_julian_double(getTime()));
// Calculate the AOS before that LOS
next_aos_time = next_los_time = predict_from_julian(next_los.time);
do
{
next_aos = predict_next_aos(satellite_observer_station, satellite_object, predict_to_julian_double(next_aos_time));
next_aos_time -= 10;
} while (predict_from_julian(next_aos.time) >= next_los_time);
next_los_time = predict_from_julian(next_los.time);
next_aos_time = predict_from_julian(next_aos.time);
sat_next_aos_pos.az = next_aos.azimuth * RAD_TO_DEG;
sat_next_aos_pos.el = 0;
sat_next_los_pos.az = next_los.azimuth * RAD_TO_DEG;
sat_next_los_pos.el = next_los.elevation * RAD_TO_DEG;
if (meridian_flip_correction)
{
// Determine pass direction
predict_position satellite_orbit2;
predict_observation observation_pos_cur;
predict_observation observation_pos_prev;
double currTime = next_aos_time;
predict_orbit(satellite_object, &satellite_orbit2, predict_to_julian_double(currTime));
predict_observe_orbit(satellite_observer_station, &satellite_orbit2, &observation_pos_prev);
currTime += 1.0;
do
{
predict_orbit(satellite_object, &satellite_orbit2, predict_to_julian_double(currTime));
predict_observe_orbit(satellite_observer_station, &satellite_orbit2, &observation_pos_cur);
if (std::abs(observation_pos_prev.azimuth - observation_pos_cur.azimuth) > (180 * DEG_TO_RAD))
{
if (next_los.azimuth > (90 * DEG_TO_RAD) && next_los.azimuth < (270 * DEG_TO_RAD))
southbound_cross = true;
else
northbound_cross = true;
}
currTime += 1.0;
observation_pos_prev = observation_pos_cur;
} while (next_los_time > currTime);
}
if (true) //(is_gui)
{
// Calculate a few points during the pass
predict_position satellite_orbit2;
predict_observation observation_pos2;
double time_step = abs(next_los_time - next_aos_time) / 50.0;
for (double ctime = next_aos_time; ctime <= next_los_time; ctime += time_step)
{
predict_orbit(satellite_object, &satellite_orbit2, predict_to_julian_double(ctime));
predict_observe_orbit(satellite_observer_station, &satellite_orbit2, &observation_pos2);
upcoming_pass_points.push_back({float(observation_pos2.azimuth * RAD_TO_DEG), float(observation_pos2.elevation * RAD_TO_DEG)});
}
}
}
upcoming_passes_mtx.unlock();
}
}
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