# include <config.h>
#endif
-#include <simgear/compiler.h>
-
-#include <string.h>
-
-#include STL_STRING
+#include "gps.hxx"
+#include <simgear/compiler.h>
#include <Aircraft/aircraft.hxx>
-#include <FDM/flight.hxx>
-#include <Controls/controls.hxx>
-#include <Scenery/scenery.hxx>
+#include <Main/fg_props.hxx>
+#include <Main/util.hxx> // for fgLowPass
+#include <Navaids/positioned.hxx>
-#include <simgear/constants.h>
+#include <simgear/math/sg_random.h>
#include <simgear/sg_inlines.h>
-#include <simgear/debug/logstream.hxx>
#include <simgear/math/sg_geodesy.hxx>
-#include <simgear/misc/sg_path.hxx>
-#include <simgear/route/route.hxx>
-#include <Airports/simple.hxx>
-#include <GUI/gui.h>
-#include <Main/fg_init.hxx>
-#include <Main/globals.hxx>
-#include <Main/fg_props.hxx>
-#include <Main/util.hxx>
-#include <Navaids/fixlist.hxx>
-#include <Navaids/navlist.hxx>
+using std::string;
-#include "gps.hxx"
+
+void SGGeodProperty::init(SGPropertyNode* base, const char* lonStr, const char* latStr, const char* altStr)
+{
+ _lon = base->getChild(lonStr, 0, true);
+ _lat = base->getChild(latStr, 0, true);
+ if (altStr) {
+ _alt = base->getChild(altStr, 0, true);
+ }
+}
-SG_USING_STD(string);
+void SGGeodProperty::init(const char* lonStr, const char* latStr, const char* altStr)
+{
+ _lon = fgGetNode(lonStr, true);
+ _lat = fgGetNode(latStr, true);
+ if (altStr) {
+ _alt = fgGetNode(altStr, true);
+ }
+}
+void SGGeodProperty::clear()
+{
+ _lon = _lat = _alt = NULL;
+}
-GPS::GPS ()
+void SGGeodProperty::operator=(const SGGeod& geod)
+{
+ _lon->setDoubleValue(geod.getLongitudeDeg());
+ _lat->setDoubleValue(geod.getLatitudeDeg());
+ if (_alt) {
+ _alt->setDoubleValue(geod.getElevationFt());
+ }
+}
+
+SGGeod SGGeodProperty::get() const
+{
+ double lon = _lon->getDoubleValue(),
+ lat = _lat->getDoubleValue();
+ if (_alt) {
+ return SGGeod::fromDegFt(lon, lat, _alt->getDoubleValue());
+ } else {
+ return SGGeod::fromDeg(lon,lat);
+ }
+}
+
+
+GPS::GPS ( SGPropertyNode *node)
: _last_valid(false),
- _last_longitude_deg(0),
- _last_latitude_deg(0),
- _last_altitude_m(0),
- _last_speed_kts(0)
+ _alt_dist_ratio(0),
+ _distance_m(0),
+ _course_deg(0),
+ _name(node->getStringValue("name", "gps")),
+ _num(node->getIntValue("number", 0))
{
}
void
GPS::init ()
{
- _longitude_node = fgGetNode("/position/longitude-deg", true);
- _latitude_node = fgGetNode("/position/latitude-deg", true);
- _altitude_node = fgGetNode("/position/altitude-ft", true);
+ string branch;
+ branch = "/instrumentation/" + _name;
+
+ SGPropertyNode *node = fgGetNode(branch.c_str(), _num, true );
+ _position.init("/position/longitude-deg", "/position/latitude-deg", "/position/altitude-ft");
_magvar_node = fgGetNode("/environment/magnetic-variation-deg", true);
- _serviceable_node = fgGetNode("/instrumentation/gps/serviceable", true);
+ _serviceable_node = node->getChild("serviceable", 0, true);
_electrical_node = fgGetNode("/systems/electrical/outputs/gps", true);
- _wp_longitude_node =
- fgGetNode("/instrumentation/gps/wp-longitude-deg", true);
- _wp_latitude_node =
- fgGetNode("/instrumentation/gps/wp-latitude-deg", true);
- _wp_ID_node =
- fgGetNode("/instrumentation/gps/wp-ID", true);
- _wp_name_node =
- fgGetNode("/instrumentation/gps/wp-name", true);
- _wp_course_node =
- fgGetNode("/instrumentation/gps/indicated-course-deg", true);
- _get_nearest_airport_node =
- fgGetNode("/instrumentation/gps/get-nearest-airport", true);
- _waypoint_type_node =
- fgGetNode("/instrumentation/gps/waypoint-type", true);
-
- _raim_node = fgGetNode("/instrumentation/gps/raim", true);
- _indicated_longitude_node =
- fgGetNode("/instrumentation/gps/indicated-longitude-deg", true);
- _indicated_latitude_node =
- fgGetNode("/instrumentation/gps/indicated-latitude-deg", true);
- _indicated_altitude_node =
- fgGetNode("/instrumentation/gps/indicated-altitude-ft", true);
+
+ SGPropertyNode *wp_node = node->getChild("wp", 0, true);
+ SGPropertyNode *wp0_node = wp_node->getChild("wp", 0, true);
+ SGPropertyNode *wp1_node = wp_node->getChild("wp", 1, true);
+
+ _wp0_position.init(wp0_node, "longitude-deg", "latitude-deg", "altitude-ft");
+ _wp0_ID_node = wp0_node->getChild("ID", 0, true);
+ _wp0_name_node = wp0_node->getChild("name", 0, true);
+ _wp0_course_node = wp0_node->getChild("desired-course-deg", 0, true);
+ _wp0_distance_node = wp0_node->getChild("distance-nm", 0, true);
+ _wp0_ttw_node = wp0_node->getChild("TTW", 0, true);
+ _wp0_bearing_node = wp0_node->getChild("bearing-true-deg", 0, true);
+ _wp0_mag_bearing_node = wp0_node->getChild("bearing-mag-deg", 0, true);
+ _wp0_course_deviation_node =
+ wp0_node->getChild("course-deviation-deg", 0, true);
+ _wp0_course_error_nm_node = wp0_node->getChild("course-error-nm", 0, true);
+ _wp0_to_flag_node = wp0_node->getChild("to-flag", 0, true);
+ _true_wp0_bearing_error_node =
+ wp0_node->getChild("true-bearing-error-deg", 0, true);
+ _magnetic_wp0_bearing_error_node =
+ wp0_node->getChild("magnetic-bearing-error-deg", 0, true);
+
+ _wp1_position.init(wp1_node, "longitude-deg", "latitude-deg", "altitude-ft");
+ _wp1_ID_node = wp1_node->getChild("ID", 0, true);
+ _wp1_name_node = wp1_node->getChild("name", 0, true);
+ _wp1_course_node = wp1_node->getChild("desired-course-deg", 0, true);
+ _wp1_distance_node = wp1_node->getChild("distance-nm", 0, true);
+ _wp1_ttw_node = wp1_node->getChild("TTW", 0, true);
+ _wp1_bearing_node = wp1_node->getChild("bearing-true-deg", 0, true);
+ _wp1_mag_bearing_node = wp1_node->getChild("bearing-mag-deg", 0, true);
+ _wp1_course_deviation_node =
+ wp1_node->getChild("course-deviation-deg", 0, true);
+ _wp1_course_error_nm_node = wp1_node->getChild("course-error-nm", 0, true);
+ _wp1_to_flag_node = wp1_node->getChild("to-flag", 0, true);
+ _true_wp1_bearing_error_node =
+ wp1_node->getChild("true-bearing-error-deg", 0, true);
+ _magnetic_wp1_bearing_error_node =
+ wp1_node->getChild("magnetic-bearing-error-deg", 0, true);
+ _get_nearest_airport_node =
+ wp1_node->getChild("get-nearest-airport", 0, true);
+
+ _tracking_bug_node = node->getChild("tracking-bug", 0, true);
+ _raim_node = node->getChild("raim", 0, true);
+
+ _indicated_pos.init(node, "indicated-longitude-deg",
+ "indicated-latitude-deg", "indicated-altitude-ft");
+
+ _indicated_vertical_speed_node =
+ node->getChild("indicated-vertical-speed", 0, true);
_true_track_node =
- fgGetNode("/instrumentation/gps/indicated-track-true-deg", true);
+ node->getChild("indicated-track-true-deg", 0, true);
_magnetic_track_node =
- fgGetNode("/instrumentation/gps/indicated-track-magnetic-deg", true);
+ node->getChild("indicated-track-magnetic-deg", 0, true);
_speed_node =
- fgGetNode("/instrumentation/gps/indicated-ground-speed-kt", true);
- _wp_distance_node =
- fgGetNode("/instrumentation/gps/wp-distance-nm", true);
- _wp_ttw_node =
- fgGetNode("/instrumentation/gps/TTW",true);
- _wp_bearing_node =
- fgGetNode("/instrumentation/gps/wp-bearing-deg", true);
- _wp_course_deviation_node =
- fgGetNode("/instrumentation/gps/course-deviation-deg", true);
- _wp_course_error_nm_node =
- fgGetNode("/instrumentation/gps/course-error-nm", true);
- _wp_to_flag_node =
- fgGetNode("/instrumentation/gps/to-flag", true);
+ node->getChild("indicated-ground-speed-kt", 0, true);
_odometer_node =
- fgGetNode("/instrumentation/gps/odometer", true);
+ node->getChild("odometer", 0, true);
_trip_odometer_node =
- fgGetNode("/instrumentation/gps/trip-odometer", true);
+ node->getChild("trip-odometer", 0, true);
+ _true_bug_error_node =
+ node->getChild("true-bug-error-deg", 0, true);
+ _magnetic_bug_error_node =
+ node->getChild("magnetic-bug-error-deg", 0, true);
+
+ _leg_distance_node =
+ wp_node->getChild("leg-distance-nm", 0, true);
+ _leg_course_node =
+ wp_node->getChild("leg-true-course-deg", 0, true);
+ _leg_magnetic_course_node =
+ wp_node->getChild("leg-mag-course-deg", 0, true);
+ _alt_dist_ratio_node =
+ wp_node->getChild("alt-dist-ratio", 0, true);
+ _leg_course_deviation_node =
+ wp_node->getChild("leg-course-deviation-deg", 0, true);
+ _leg_course_error_nm_node =
+ wp_node->getChild("leg-course-error-nm", 0, true);
+ _leg_to_flag_node =
+ wp_node->getChild("leg-to-flag", 0, true);
+ _alt_deviation_node =
+ wp_node->getChild("alt-deviation-ft", 0, true);
+
+ _serviceable_node->setBoolValue(true);
+}
+
+void
+GPS::clearOutput()
+{
+ _last_valid = false;
+ _last_speed_kts = 0;
+ _last_pos = SGGeod();
+ _raim_node->setDoubleValue(false);
+ _indicated_pos = SGGeod();
+ _indicated_vertical_speed_node->setDoubleValue(0);
+ _true_track_node->setDoubleValue(0);
+ _magnetic_track_node->setDoubleValue(0);
+ _speed_node->setDoubleValue(0);
+ _wp1_distance_node->setDoubleValue(0);
+ _wp1_bearing_node->setDoubleValue(0);
+ _wp1_position = SGGeod();
+ _wp1_course_node->setDoubleValue(0);
+ _odometer_node->setDoubleValue(0);
+ _trip_odometer_node->setDoubleValue(0);
+ _tracking_bug_node->setDoubleValue(0);
+ _true_bug_error_node->setDoubleValue(0);
+ _magnetic_bug_error_node->setDoubleValue(0);
+ _true_wp1_bearing_error_node->setDoubleValue(0);
+ _magnetic_wp1_bearing_error_node->setDoubleValue(0);
}
void
GPS::update (double delta_time_sec)
{
- // If it's off, don't bother.
- if (!_serviceable_node->getBoolValue() ||
- !_electrical_node->getBoolValue()) {
- _last_valid = false;
- _last_longitude_deg = 0;
- _last_latitude_deg = 0;
- _last_altitude_m = 0;
- _last_speed_kts = 0;
- _raim_node->setDoubleValue(false);
- _indicated_longitude_node->setDoubleValue(0);
- _indicated_latitude_node->setDoubleValue(0);
- _indicated_altitude_node->setDoubleValue(0);
- _true_track_node->setDoubleValue(0);
- _magnetic_track_node->setDoubleValue(0);
- _speed_node->setDoubleValue(0);
- _wp_distance_node->setDoubleValue(0);
- _wp_bearing_node->setDoubleValue(0);
- _wp_longitude_node->setDoubleValue(0);
- _wp_latitude_node->setDoubleValue(0);
- _wp_course_node->setDoubleValue(0);
- _odometer_node->setDoubleValue(0);
- _trip_odometer_node->setDoubleValue(0);
+ // If it's off, don't bother.
+ if (!_serviceable_node->getBoolValue() || !_electrical_node->getBoolValue()) {
+ clearOutput();
return;
}
- // Get the aircraft position
- double longitude_deg = _longitude_node->getDoubleValue();
- double latitude_deg = _latitude_node->getDoubleValue();
- double altitude_m = _altitude_node->getDoubleValue() * SG_FEET_TO_METER;
- double magvar_deg = _magvar_node->getDoubleValue();
+ UpdateContext ctx;
+ ctx.dt = delta_time_sec;
+ ctx.waypoint_changed = false;
+ ctx.pos = _position.get();
+
+ // TODO: Add noise and other errors.
+/*
+
+ // Bias and random error
+ double random_factor = sg_random();
+ double random_error = 1.4;
+ double error_radius = 5.1;
+ double bias_max_radius = 5.1;
+ double random_max_radius = 1.4;
+
+ bias_length += (random_factor-0.5) * 1.0e-3;
+ if (bias_length <= 0.0) bias_length = 0.0;
+ else if (bias_length >= bias_max_radius) bias_length = bias_max_radius;
+ bias_angle += (random_factor-0.5) * 1.0e-3;
+ if (bias_angle <= 0.0) bias_angle = 0.0;
+ else if (bias_angle >= 360.0) bias_angle = 360.0;
- double speed_kt;
+ double random_length = random_factor * random_max_radius;
+ double random_angle = random_factor * 360.0;
+ double bias_x = bias_length * cos(bias_angle * SG_PI / 180.0);
+ double bias_y = bias_length * sin(bias_angle * SG_PI / 180.0);
+ double random_x = random_length * cos(random_angle * SG_PI / 180.0);
+ double random_y = random_length * sin(random_angle * SG_PI / 180.0);
+ double error_x = bias_x + random_x;
+ double error_y = bias_y + random_y;
+ double error_length = sqrt(error_x*error_x + error_y*error_y);
+ double error_angle = atan(error_y / error_x) * 180.0 / SG_PI;
+
+ double lat2;
+ double lon2;
+ double az2;
+ geo_direct_wgs_84 ( altitude_m, latitude_deg,
+ longitude_deg, error_angle,
+ error_length, &lat2, &lon2,
+ &az2 );
+ //cout << lat2 << " " << lon2 << endl;
+ printf("%f %f \n", bias_length, bias_angle);
+ printf("%3.7f %3.7f \n", lat2, lon2);
+ printf("%f %f \n", error_length, error_angle);
+
+*/
_raim_node->setBoolValue(true);
- _indicated_longitude_node->setDoubleValue(longitude_deg);
- _indicated_latitude_node->setDoubleValue(latitude_deg);
- _indicated_altitude_node->setDoubleValue(altitude_m * SG_METER_TO_FEET);
+ _indicated_pos = ctx.pos;
if (_last_valid) {
- double track1_deg, track2_deg, distance_m, odometer;
- geo_inverse_wgs_84(altitude_m,
- _last_latitude_deg, _last_longitude_deg,
- latitude_deg, longitude_deg,
- &track1_deg, &track2_deg, &distance_m);
- speed_kt = ((distance_m * SG_METER_TO_NM) *
- ((1 / delta_time_sec) * 3600.0));
- _true_track_node->setDoubleValue(track1_deg);
- _magnetic_track_node->setDoubleValue(track1_deg - magvar_deg);
- speed_kt = fgGetLowPass(_last_speed_kts, speed_kt, delta_time_sec/20.0);
- _last_speed_kts = speed_kt;
- _speed_node->setDoubleValue(speed_kt);
-
- odometer = _odometer_node->getDoubleValue();
- _odometer_node->setDoubleValue(odometer + distance_m * SG_METER_TO_NM);
- odometer = _trip_odometer_node->getDoubleValue();
- _trip_odometer_node->setDoubleValue(odometer + distance_m * SG_METER_TO_NM);
-
- // Get waypoint position
- double wp_longitude_deg = _wp_longitude_node->getDoubleValue();
- double wp_latitude_deg = _wp_latitude_node->getDoubleValue();
- double wp_course_deg =
- _wp_course_node->getDoubleValue();
- double wp_distance, wp_bearing_deg, wp_course_deviation_deg,
- wp_course_error_m, wp_TTW;
- // double wp_actual_radial_deg;
- string wp_ID = _wp_ID_node->getStringValue();
-
- // If the get-nearest-airport-node is true.
- // Get the nearest airport, and set it as waypoint.
- if (_get_nearest_airport_node->getBoolValue()) {
- FGAirport a;
- cout << "Airport found" << endl;
- a = globals->get_airports()->search(longitude_deg, latitude_deg, false);
- _wp_ID_node->setStringValue(a.id.c_str());
- wp_longitude_deg = a.longitude;
- wp_latitude_deg = a.latitude;
- _wp_name_node->setStringValue(a.name.c_str());
- _get_nearest_airport_node->setBoolValue(false);
- _last_wp_ID = wp_ID = a.id.c_str();
- }
-
- // If the waypoint ID has changed, try to find the new ID
- // in the airport-, fix-, nav-database.
- if ( !(_last_wp_ID == wp_ID) ) {
- string waypont_type =
- _waypoint_type_node->getStringValue();
- if (waypont_type == "airport") {
- FGAirport a;
- a = globals->get_airports()->search( wp_ID );
- if ( a.id == wp_ID ) {
- cout << "Airport found" << endl;
- wp_longitude_deg = a.longitude;
- wp_latitude_deg = a.latitude;
- _wp_name_node->setStringValue(a.name.c_str());
- }
- }
- else if (waypont_type == "nav") {
- FGNav * n;
- if ( (n = current_navlist->findByIdent(wp_ID.c_str(),
- longitude_deg,
- latitude_deg)) != NULL) {
- cout << "Nav found" << endl;
- wp_longitude_deg = n->get_lon();
- wp_latitude_deg = n->get_lat();
- _wp_name_node->setStringValue(n->get_name().c_str());
- }
- }
- else if (waypont_type == "fix") {
- FGFix f;
- if ( current_fixlist->query(wp_ID, &f) ) {
- cout << "Fix found" << endl;
- wp_longitude_deg = f.get_lon();
- wp_latitude_deg = f.get_lat();
- _wp_name_node->setStringValue(wp_ID.c_str());
- }
- }
- _last_wp_ID = wp_ID;
- }
-
- // Find the bearing and distance to the waypoint.
- SGWayPoint wp(wp_longitude_deg, wp_latitude_deg, altitude_m);
- wp.CourseAndDistance(longitude_deg, latitude_deg, altitude_m,
- &wp_bearing_deg, &wp_distance);
- _wp_longitude_node->setDoubleValue(wp_longitude_deg);
- _wp_latitude_node->setDoubleValue(wp_latitude_deg);
- _wp_distance_node->setDoubleValue(wp_distance * SG_METER_TO_NM);
- _wp_bearing_node->setDoubleValue(wp_bearing_deg);
-
- // Estimate time to waypoint.
- // The estimation does not take track into consideration,
- // so if you are going away from the waypoint the TTW will
- // increase. Makes most sense when travelling directly towards
- // the waypoint.
- if (speed_kt > 0.0 && wp_distance > 0.0) {
- wp_TTW = (wp_distance * SG_METER_TO_NM) / (speed_kt / 3600);
- }
- else {
- wp_TTW = 0.0;
- }
- unsigned int wp_TTW_seconds = (int) (wp_TTW + 0.5);
- if (wp_TTW_seconds < 356400) { // That's 99 hours
- unsigned int wp_TTW_minutes = 0;
- unsigned int wp_TTW_hours = 0;
- char wp_TTW_str[8];
- while (wp_TTW_seconds >= 3600) {
- wp_TTW_seconds -= 3600;
- wp_TTW_hours++;
- }
- while (wp_TTW_seconds >= 60) {
- wp_TTW_seconds -= 60;
- wp_TTW_minutes++;
- }
- sprintf(wp_TTW_str, "%02d:%02d:%02d",
- wp_TTW_hours, wp_TTW_minutes, wp_TTW_seconds);
- _wp_ttw_node->setStringValue(wp_TTW_str);
- }
- else
- _wp_ttw_node->setStringValue("--:--:--");
-
- // Course deviation is the diffenrence between the bearing
- // and the course.
- wp_course_deviation_deg = wp_bearing_deg -
- wp_course_deg;
- while (wp_course_deviation_deg < -180.0) {
- wp_course_deviation_deg += 360.0; }
- while (wp_course_deviation_deg > 180.0) {
- wp_course_deviation_deg -= 360.0; }
-
- // If the course deviation is less than 90 degrees to either side,
- // our desired course is towards the waypoint.
- // It does not matter if we are actually moving towards or from the waypoint.
- if (fabs(wp_course_deviation_deg) < 90.0) {
- _wp_to_flag_node->setBoolValue(true); }
- // If it's more than 90 degrees the desired course is from the waypoint.
- else if (fabs(wp_course_deviation_deg) > 90.0) {
- _wp_to_flag_node->setBoolValue(false);
- // When the course is away from the waypoint,
- // it makes sense to change the sign of the deviation.
- wp_course_deviation_deg *= -1.0;
- while (wp_course_deviation_deg < -90.0)
- wp_course_deviation_deg += 180.0;
- while (wp_course_deviation_deg > 90.0)
- wp_course_deviation_deg -= 180.0; }
-
- _wp_course_deviation_node->setDoubleValue(wp_course_deviation_deg);
-
- // Cross track error.
- wp_course_error_m = sin(wp_course_deviation_deg * SG_PI / 180.0)
- * (wp_distance);
- _wp_course_error_nm_node->setDoubleValue(wp_course_error_m
- * SG_METER_TO_NM);
-
+ updateWithValid(ctx);
} else {
_true_track_node->setDoubleValue(0.0);
_magnetic_track_node->setDoubleValue(0.0);
_speed_node->setDoubleValue(0.0);
+ _last_valid = true;
+ }
+
+ _last_pos = ctx.pos;
+}
+
+void
+GPS::updateNearestAirport(UpdateContext& ctx)
+{
+ if (!_get_nearest_airport_node->getBoolValue()) {
+ return;
+ }
+
+ // If the get-nearest-airport-node is true.
+ // Get the nearest airport, and set it as waypoint 1.
+
+ FGPositioned::TypeFilter aptFilter(FGPositioned::AIRPORT);
+ FGPositionedRef a = FGPositioned::findClosest(ctx.pos, 360.0, &aptFilter);
+ if (!a) {
+ return;
+ }
+
+ _wp1_position = a->geod();
+ _wp1_ID_node->setStringValue(a->ident().c_str());
+ _wp1_name_node->setStringValue(a->name().c_str());
+ _get_nearest_airport_node->setBoolValue(false);
+ _last_wp1_ID = a->ident(); // don't trigger updateWaypoint1();
+ ctx.waypoint_changed = true;
+}
+
+void
+GPS::updateWithValid(UpdateContext& ctx)
+{
+ assert(_last_valid);
+ double distance_m;
+ SGGeodesy::inverse(_last_pos, ctx.pos, ctx.track1_deg, ctx.track2_deg, distance_m );
+
+ ctx.speed_kt = ((distance_m * SG_METER_TO_NM) * ((1 / ctx.dt) * 3600.0));
+
+ double vertical_speed_mpm = ((ctx.pos.getElevationM() - _last_pos.getElevationM()) * 60 /
+ ctx.dt);
+ _indicated_vertical_speed_node->setDoubleValue(vertical_speed_mpm * SG_METER_TO_FEET);
+ _true_track_node->setDoubleValue(ctx.track1_deg);
+
+ ctx.magvar_deg = _magvar_node->getDoubleValue();
+ double mag_track_bearing = ctx.track1_deg - ctx.magvar_deg;
+ SG_NORMALIZE_RANGE(mag_track_bearing, 0.0, 360.0);
+ _magnetic_track_node->setDoubleValue(mag_track_bearing);
+ ctx.speed_kt = fgGetLowPass(_last_speed_kts, ctx.speed_kt, ctx.dt/20.0);
+ _last_speed_kts = ctx.speed_kt;
+ _speed_node->setDoubleValue(ctx.speed_kt);
+
+ double odometer = _odometer_node->getDoubleValue();
+ _odometer_node->setDoubleValue(odometer + distance_m * SG_METER_TO_NM);
+ odometer = _trip_odometer_node->getDoubleValue();
+ _trip_odometer_node->setDoubleValue(odometer + distance_m * SG_METER_TO_NM);
+
+ updateNearestAirport(ctx);
+ updateWaypoint0(ctx);
+ updateWaypoint1(ctx);
+
+ ctx.wp0_pos = _wp0_position.get();
+ ctx.wp1_pos = _wp1_position.get();
+ // if this flag is set, we need to recompute leg data, because either
+ // WP0 or WP1 has been updated
+ if (ctx.waypoint_changed) {
+ waypointChanged(ctx);
}
- _last_valid = true;
- _last_longitude_deg = longitude_deg;
- _last_latitude_deg = latitude_deg;
- _last_altitude_m = altitude_m;
+ ctx.wp0_course_deg = _wp0_course_node->getDoubleValue();
+ ctx.wp1_course_deg = _wp1_course_node->getDoubleValue();
+
+ updateWaypoint0Course(ctx);
+ updateWaypoint1Course(ctx);
+ updateLegCourse(ctx);
+
+ // Altitude deviation
+ //double desired_altitude_m = wp1_altitude_m
+ // + wp1_distance * _alt_dist_ratio;
+ //double altitude_deviation_m = altitude_m - desired_altitude_m;
+ // _alt_deviation_node->setDoubleValue(altitude_deviation_m * SG_METER_TO_FEET);
+
+ updateTrackingBug(ctx);
+}
+
+void
+GPS::updateLegCourse(UpdateContext& ctx)
+{
+ // Leg course deviation is the diffenrence between the bearing
+ // and the course.
+ double course_deviation_deg = ctx.wp1_bearing_deg - _course_deg;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -180.0, 180.0);
+
+ // If the course deviation is less than 90 degrees to either side,
+ // our desired course is towards the waypoint.
+ // It does not matter if we are actually moving
+ // towards or from the waypoint.
+ if (fabs(course_deviation_deg) < 90.0) {
+ _leg_to_flag_node->setBoolValue(true);
+ }
+ // If it's more than 90 degrees the desired
+ // course is from the waypoint.
+ else if (fabs(course_deviation_deg) > 90.0) {
+ _leg_to_flag_node->setBoolValue(false);
+ // When the course is away from the waypoint,
+ // it makes sense to change the sign of the deviation.
+ course_deviation_deg *= -1.0;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -90.0, 90.0);
+ }
+
+ _leg_course_deviation_node->setDoubleValue(course_deviation_deg);
+
+ // Cross track error.
+ double course_error_m = sin(course_deviation_deg * SG_PI / 180.0)
+ * (_distance_m);
+ _leg_course_error_nm_node->setDoubleValue(course_error_m * SG_METER_TO_NM);
+
+}
+
+void
+GPS::updateTrackingBug(UpdateContext& ctx)
+{
+ double tracking_bug = _tracking_bug_node->getDoubleValue();
+ double true_bug_error = tracking_bug - ctx.track1_deg;
+ double magnetic_bug_error = tracking_bug - _magnetic_track_node->getDoubleValue();
+
+ // Get the errors into the (-180,180) range.
+ SG_NORMALIZE_RANGE(true_bug_error, -180.0, 180.0);
+ SG_NORMALIZE_RANGE(magnetic_bug_error, -180.0, 180.0);
+
+ _true_bug_error_node->setDoubleValue(true_bug_error);
+ _magnetic_bug_error_node->setDoubleValue(magnetic_bug_error);
+}
+
+void
+GPS::waypointChanged(UpdateContext& ctx)
+{
+ // If any of the two waypoints have changed
+ // we need to calculate a new course between them,
+ // and values for vertical navigation.
+ assert(ctx.waypoint_changed);
+
+ double track2;
+ SGGeodesy::inverse(ctx.wp0_pos, ctx.wp1_pos, _course_deg, track2, _distance_m);
+
+ double leg_mag_course = _course_deg - _magvar_node->getDoubleValue();
+ SG_NORMALIZE_RANGE(leg_mag_course, 0.0, 360.0);
+
+ // Get the altitude / distance ratio
+ if ( _distance_m > 0.0 ) {
+ double alt_difference_m = ctx.wp0_pos.getElevationM() - ctx.wp1_pos.getElevationM();
+ _alt_dist_ratio = alt_difference_m / _distance_m;
+ }
+
+ _leg_distance_node->setDoubleValue(_distance_m * SG_METER_TO_NM);
+ _leg_course_node->setDoubleValue(_course_deg);
+ _leg_magnetic_course_node->setDoubleValue(leg_mag_course);
+ _alt_dist_ratio_node->setDoubleValue(_alt_dist_ratio);
+}
+
+void
+GPS::updateWaypoint0(UpdateContext& ctx)
+{
+ string id(_wp0_ID_node->getStringValue());
+ if (_last_wp0_ID == id) {
+ return; // easy, nothing to do
+ }
+
+ FGPositionedRef result = FGPositioned::findClosestWithIdent(id, ctx.pos);
+ if (!result) {
+ // not found, hmm
+ _last_wp0_ID = id;
+ return;
+ }
+
+ _wp0_position = result->geod();
+ _wp0_name_node->setStringValue(result->name().c_str());
+ _last_wp0_ID = id;
+ ctx.waypoint_changed = true;
+}
+
+void
+GPS::updateWaypoint1(UpdateContext& ctx)
+{
+ string id(_wp1_ID_node->getStringValue());
+ if (_last_wp1_ID == id) {
+ return; // easy, nothing to do
+ }
+
+ FGPositionedRef result = FGPositioned::findClosestWithIdent(id, ctx.pos);
+ if (!result) {
+ // not found, hmm
+ _last_wp1_ID = id;
+ return;
+ }
+
+ _wp1_position = result->geod();
+ _wp1_name_node->setStringValue(result->name().c_str());
+ _last_wp1_ID = id;
+ ctx.waypoint_changed = true;
+}
+
+void
+GPS::updateTTWNode(UpdateContext& ctx, double distance_m, SGPropertyNode_ptr node)
+{
+ // Estimate time to waypoint.
+ // The estimation does not take track into consideration,
+ // so if you are going away from the waypoint the TTW will
+ // increase. Makes most sense when travelling directly towards
+ // the waypoint.
+ double TTW = 0.0;
+ if (ctx.speed_kt > 0.0 && distance_m > 0.0) {
+ TTW = (distance_m * SG_METER_TO_NM) / (ctx.speed_kt / 3600);
+ }
+ if (TTW < 356400.5) { // That's 99 hours
+ unsigned int TTW_seconds = (int) (TTW + 0.5);
+ unsigned int TTW_minutes = 0;
+ unsigned int TTW_hours = 0;
+ char TTW_str[9];
+ TTW_hours = TTW_seconds / 3600;
+ TTW_minutes = (TTW_seconds / 60) % 60;
+ TTW_seconds = TTW_seconds % 60;
+ snprintf(TTW_str, 9, "%02d:%02d:%02d",
+ TTW_hours, TTW_minutes, TTW_seconds);
+ node->setStringValue(TTW_str);
+ } else {
+ node->setStringValue("--:--:--");
+ }
+}
+
+void
+GPS::updateWaypoint0Course(UpdateContext& ctx)
+{
+ // Find the bearing and distance to waypoint 0.
+ double az2;
+ SGGeodesy::inverse(ctx.pos, ctx.wp0_pos, ctx.wp0_bearing_deg, az2,ctx.wp0_distance);
+ _wp0_distance_node->setDoubleValue(ctx.wp0_distance * SG_METER_TO_NM);
+ _wp0_bearing_node->setDoubleValue(ctx.wp0_bearing_deg);
+
+ double mag_bearing_deg = ctx.wp0_bearing_deg - ctx.magvar_deg;
+ SG_NORMALIZE_RANGE(mag_bearing_deg, 0.0, 360.0);
+ _wp0_mag_bearing_node->setDoubleValue(mag_bearing_deg);
+ double bearing_error_deg = ctx.track1_deg - ctx.wp0_bearing_deg;
+ SG_NORMALIZE_RANGE(bearing_error_deg, -180.0, 180.0);
+ _true_wp0_bearing_error_node->setDoubleValue(bearing_error_deg);
+
+ updateTTWNode(ctx, ctx.wp0_distance, _wp0_ttw_node);
+
+ // Course deviation is the diffenrence between the bearing
+ // and the course.
+ double course_deviation_deg = ctx.wp0_bearing_deg -
+ ctx.wp0_course_deg;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -180.0, 180.0);
+
+ // If the course deviation is less than 90 degrees to either side,
+ // our desired course is towards the waypoint.
+ // It does not matter if we are actually moving
+ // towards or from the waypoint.
+ if (fabs(course_deviation_deg) < 90.0) {
+ _wp0_to_flag_node->setBoolValue(true);
+ }
+ // If it's more than 90 degrees the desired
+ // course is from the waypoint.
+ else if (fabs(course_deviation_deg) > 90.0) {
+ _wp0_to_flag_node->setBoolValue(false);
+ // When the course is away from the waypoint,
+ // it makes sense to change the sign of the deviation.
+ course_deviation_deg *= -1.0;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -90.0, 90.0);
+ }
+
+ _wp0_course_deviation_node->setDoubleValue(course_deviation_deg);
+
+ // Cross track error.
+ double course_error_m = sin(course_deviation_deg * SG_PI / 180.0)
+ * (ctx.wp0_distance);
+ _wp0_course_error_nm_node->setDoubleValue(course_error_m * SG_METER_TO_NM);
+}
+
+void
+GPS::updateWaypoint1Course(UpdateContext& ctx)
+{
+ // Find the bearing and distance to waypoint 0.
+ double az2;
+ SGGeodesy::inverse(ctx.pos, ctx.wp1_pos, ctx.wp1_bearing_deg, az2,ctx.wp1_distance);
+ _wp1_distance_node->setDoubleValue(ctx.wp1_distance * SG_METER_TO_NM);
+ _wp1_bearing_node->setDoubleValue(ctx.wp1_bearing_deg);
+
+ double mag_bearing_deg = ctx.wp1_bearing_deg - ctx.magvar_deg;
+ SG_NORMALIZE_RANGE(mag_bearing_deg, 0.0, 360.0);
+ _wp1_mag_bearing_node->setDoubleValue(mag_bearing_deg);
+ double bearing_error_deg = ctx.track1_deg - ctx.wp1_bearing_deg;
+ SG_NORMALIZE_RANGE(bearing_error_deg, -180.0, 180.0);
+ _true_wp1_bearing_error_node->setDoubleValue(bearing_error_deg);
+
+ updateTTWNode(ctx, ctx.wp1_distance, _wp1_ttw_node);
+
+ // Course deviation is the diffenrence between the bearing
+ // and the course.
+ double course_deviation_deg = ctx.wp1_bearing_deg -
+ ctx.wp1_course_deg;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -180.0, 180.0);
+
+ // If the course deviation is less than 90 degrees to either side,
+ // our desired course is towards the waypoint.
+ // It does not matter if we are actually moving
+ // towards or from the waypoint.
+ if (fabs(course_deviation_deg) < 90.0) {
+ _wp1_to_flag_node->setBoolValue(true);
+ }
+ // If it's more than 90 degrees the desired
+ // course is from the waypoint.
+ else if (fabs(course_deviation_deg) > 90.0) {
+ _wp1_to_flag_node->setBoolValue(false);
+ // When the course is away from the waypoint,
+ // it makes sense to change the sign of the deviation.
+ course_deviation_deg *= -1.0;
+ SG_NORMALIZE_RANGE(course_deviation_deg, -90.0, 90.0);
+ }
+
+ _wp1_course_deviation_node->setDoubleValue(course_deviation_deg);
+
+ // Cross track error.
+ double course_error_m = sin(course_deviation_deg * SG_PI / 180.0)
+ * (ctx.wp1_distance);
+ _wp1_course_error_nm_node->setDoubleValue(course_error_m * SG_METER_TO_NM);
+
}
// end of gps.cxx