// navlist.cxx -- navaids management class // // Written by Curtis Olson, started April 2000. // // Copyright (C) 2000 Curtis L. Olson - http://www.flightgear.org/~curt // // 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; either version 2 of the // License, or (at your option) any later version. // // 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, write to the Free Software // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. // // $Id$ #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include "navlist.hxx" // Return true if the nav record matches the type static bool isTypeMatch(const FGNavRecord* n, fg_nav_types type) { switch(type) { case FG_NAV_ANY: return(true); case FG_NAV_VOR: return(n->get_type() == 3); case FG_NAV_NDB: return(n->get_type() == 2); case FG_NAV_ILS: return(n->get_type() == 4); // Note - very simplified, only matches loc as part of full ILS. default: return false; } } // Constructor FGNavList::FGNavList( void ) { } FGTACANList::FGTACANList( void ){ } // Destructor FGNavList::~FGNavList( void ) { } FGTACANList::~FGTACANList( void ){ } // load the navaids and build the map bool FGNavList::init() { // FIXME: leaves all the individual navaid entries leaked navaids.erase( navaids.begin(), navaids.end() ); navaids_by_tile.erase( navaids_by_tile.begin(), navaids_by_tile.end() ); ident_navaids.erase( ident_navaids.begin(), ident_navaids.end() ); return true; } bool FGTACANList::init() { return true; } // real add a marker beacon static void real_add( nav_map_type &navmap, const int master_index, FGNavRecord *n ) { navmap[master_index].push_back( n ); } // front end for add a marker beacon static void tile_add( nav_map_type &navmap, FGNavRecord *n ) { double diff; double lon = n->get_lon(); double lat = n->get_lat(); int lonidx = (int)lon; diff = lon - (double)lonidx; if ( (lon < 0.0) && (fabs(diff) > SG_EPSILON) ) { lonidx -= 1; } double lonfrac = lon - (double)lonidx; lonidx += 180; int latidx = (int)lat; diff = lat - (double)latidx; if ( (lat < 0.0) && (fabs(diff) > SG_EPSILON) ) { latidx -= 1; } double latfrac = lat - (double)latidx; latidx += 90; int master_index = lonidx * 1000 + latidx; // cout << "lonidx = " << lonidx << " latidx = " << latidx << " "; // cout << "Master index = " << master_index << endl; // add to the actual bucket real_add( navmap, master_index, n ); // if we are close to the edge, add to adjacent buckets so we only // have to search one bucket at run time // there are 8 cases since there are 8 adjacent tiles if ( lonfrac < 0.2 ) { real_add( navmap, master_index - 1000, n ); if ( latfrac < 0.2 ) { real_add( navmap, master_index - 1000 - 1, n ); } else if ( latfrac > 0.8 ) { real_add( navmap, master_index - 1000 + 1, n ); } } else if ( lonfrac > 0.8 ) { real_add( navmap, master_index + 1000, n ); if ( latfrac < 0.2 ) { real_add( navmap, master_index + 1000 - 1, n ); } else if ( latfrac > 0.8 ) { real_add( navmap, master_index + 1000 + 1, n ); } } else if ( latfrac < 0.2 ) { real_add( navmap, master_index - 1, n ); } else if ( latfrac > 0.8 ) { real_add( navmap, master_index + 1, n ); } } // add an entry to the lists bool FGNavList::add( FGNavRecord *n ) { navaids[n->get_freq()].push_back(n); ident_navaids[n->get_ident()].push_back(n); tile_add( navaids_by_tile, n ); return true; } // add an entry to the lists bool FGTACANList::add( FGTACANRecord *c ) { ident_channels[c->get_channel()].push_back(c); return true; } FGNavRecord *FGNavList::findByFreq( double freq, double lon, double lat, double elev ) { nav_list_type stations = navaids[(int)(freq*100.0 + 0.5)]; Point3D aircraft = sgGeodToCart( Point3D(lon, lat, elev) ); SG_LOG( SG_INSTR, SG_DEBUG, "findbyFreq " << freq << " size " << stations.size() ); return findNavFromList( aircraft, stations ); } FGNavRecord *FGNavList::findByIdent( const char* ident, const double lon, const double lat ) { nav_list_type stations = ident_navaids[ident]; Point3D aircraft = sgGeodToCart( Point3D(lon, lat, 0.0) ); return findNavFromList( aircraft, stations ); } nav_list_type FGNavList::findFirstByIdent( string ident, fg_nav_types type, bool exact) { nav_list_type n2; n2.clear(); int iType; if(type == FG_NAV_VOR) iType = 3; else if(type == FG_NAV_NDB) iType = 2; else return(n2); nav_ident_map_iterator it; if(exact) { it = ident_navaids.find(ident); } else { bool typeMatch = false; int safety_count = 0; it = ident_navaids.lower_bound(ident); while(!typeMatch) { nav_list_type n0 = it->second; // local copy, so we should be able to do anything with n0. // Remove the types that don't match request. for(nav_list_iterator it0 = n0.begin(); it0 != n0.end();) { FGNavRecord* nv = *it0; if(nv->get_type() == iType) { typeMatch = true; ++it0; } else { it0 = n0.erase(it0); } } if(typeMatch) { return(n0); } if(it == ident_navaids.begin()) { // We didn't find a match before reaching the beginning of the map n0.clear(); return(n0); } safety_count++; if(safety_count == 1000000) { SG_LOG(SG_INSTR, SG_ALERT, "safety_count triggered exit from while loop in findFirstByIdent!"); break; } ++it; if(it == ident_navaids.end()) { n0.clear(); return(n0); } } } if(it == ident_navaids.end()) { n2.clear(); return(n2); } else { nav_list_type n1 = it->second; n2.clear(); for(nav_list_iterator it2 = n1.begin(); it2 != n1.end(); ++it2) { FGNavRecord* nv = *it2; if(nv->get_type() == iType) n2.push_back(nv); } return(n2); } } // Given an Ident and optional freqency, return the first matching // station. FGNavRecord *FGNavList::findByIdentAndFreq( const char* ident, const double freq ) { nav_list_type stations = ident_navaids[ident]; SG_LOG( SG_INSTR, SG_DEBUG, "findByIdent " << ident<< " size " << stations.size() ); if ( freq > 0.0 ) { // sometimes there can be duplicated idents. If a freq is // specified, use it to refine the search. int f = (int)(freq*100.0 + 0.5); for ( unsigned int i = 0; i < stations.size(); ++i ) { if ( f == stations[i]->get_freq() ) { return stations[i]; } } } else if (stations.size()) { return stations[0]; } return NULL; } // Given a point and a list of stations, return the closest one to the // specified point. FGNavRecord *FGNavList::findNavFromList( const Point3D &aircraft, const nav_list_type &stations ) { FGNavRecord *nav = NULL; Point3D station; double d2; // in meters squared double min_dist = FG_NAV_MAX_RANGE*SG_NM_TO_METER*FG_NAV_MAX_RANGE*SG_NM_TO_METER; // find the closest station within a sensible range (FG_NAV_MAX_RANGE) for ( unsigned int i = 0; i < stations.size(); ++i ) { // cout << "testing " << current->get_ident() << endl; station = Point3D( stations[i]->get_x(), stations[i]->get_y(), stations[i]->get_z() ); d2 = aircraft.distance3Dsquared( station ); // cout << " dist = " << sqrt(d) // << " range = " << current->get_range() * SG_NM_TO_METER // << endl; // LOC, ILS, GS, and DME antenna's could potentially be // installed at the opposite end of the runway. So it's not // enough to simply find the closest antenna with the right // frequency. We need the closest antenna with the right // frequency that is most oriented towards us. (We penalize // stations that are facing away from us by adding 5000 meters // which is further than matching stations would ever be // placed from each other. (Do the expensive check only for // directional atennas and only when there is a chance it is // the closest station.) if ( d2 < min_dist && (stations[i]->get_type() == 4 || stations[i]->get_type() == 5 || stations[i]->get_type() == 6 || stations[i]->get_type() == 12) ) { double hdg_deg = 0.0; if ( stations[i]->get_type() == 4 || stations[i]->get_type() == 5 ){ hdg_deg = stations[i]->get_multiuse(); } else if ( stations[i]->get_type() == 6 ) { int tmp = (int)(stations[i]->get_multiuse() / 1000.0); hdg_deg = stations[i]->get_multiuse() - (tmp * 1000); } else if ( stations[i]->get_type() == 12 ) { // oops, Robin's data format doesn't give us the // needed information to compute a heading for a DME // transmitter. FIXME Robin! } double az1 = 0.0, az2 = 0.0, s = 0.0; double elev_m = 0.0, lat_rad = 0.0, lon_rad = 0.0; double xyz[3] = { aircraft.x(), aircraft.y(), aircraft.z() }; sgCartToGeod( xyz, &lat_rad, &lon_rad, &elev_m ); geo_inverse_wgs_84( elev_m, lat_rad * SG_RADIANS_TO_DEGREES, lon_rad * SG_RADIANS_TO_DEGREES, stations[i]->get_lat(), stations[i]->get_lon(), &az1, &az2, &s); az1 = az1 - stations[i]->get_multiuse(); if ( az1 > 180.0) az1 -= 360.0; if ( az1 < -180.0) az1 += 360.0; // penalize opposite facing stations by adding 5000 meters // (squared) which is further than matching stations would // ever be placed from each other. if ( fabs(az1) > 90.0 ) { double dist = sqrt(d2); d2 = (dist + 5000) * (dist + 5000); } } if ( d2 < min_dist ) { min_dist = d2; nav = stations[i]; } } return nav; } // returns the closest entry to the give lon/lat/elev FGNavRecord *FGNavList::findClosest( double lon_rad, double lat_rad, double elev_m, fg_nav_types type) { FGNavRecord *result = NULL; double diff; double lon_deg = lon_rad * SG_RADIANS_TO_DEGREES; double lat_deg = lat_rad * SG_RADIANS_TO_DEGREES; int lonidx = (int)lon_deg; diff = lon_deg - (double)lonidx; if ( (lon_deg < 0.0) && (fabs(diff) > SG_EPSILON) ) { lonidx -= 1; } lonidx += 180; int latidx = (int)lat_deg; diff = lat_deg - (double)latidx; if ( (lat_deg < 0.0) && (fabs(diff) > SG_EPSILON) ) { latidx -= 1; } latidx += 90; int master_index = lonidx * 1000 + latidx; nav_list_type navs = navaids_by_tile[ master_index ]; // cout << "Master index = " << master_index << endl; // cout << "beacon search length = " << beacons.size() << endl; nav_list_const_iterator current = navs.begin(); nav_list_const_iterator last = navs.end(); Point3D aircraft = sgGeodToCart( Point3D(lon_rad, lat_rad, elev_m) ); double min_dist = 999999999.0; for ( ; current != last ; ++current ) { if(isTypeMatch(*current, type)) { // cout << " testing " << (*current)->get_ident() << endl; Point3D station = Point3D( (*current)->get_x(), (*current)->get_y(), (*current)->get_z() ); // cout << " aircraft = " << aircraft << " station = " << station // << endl; double d = aircraft.distance3Dsquared( station ); // meters^2 // cout << " distance = " << d << " (" // << FG_ILS_DEFAULT_RANGE * SG_NM_TO_METER // * FG_ILS_DEFAULT_RANGE * SG_NM_TO_METER // << ")" << endl; // cout << " range = " << sqrt(d) << endl; if ( d < min_dist ) { min_dist = d; result = (*current); } } } // cout << "lon = " << lon << " lat = " << lat // << " closest beacon = " << sqrt( min_dist ) << endl; return result; } // Given a TACAN Channel return the first matching frequency FGTACANRecord *FGTACANList::findByChannel( const string& channel ) { tacan_list_type stations = ident_channels[channel]; SG_LOG( SG_INSTR, SG_DEBUG, "findByChannel " << channel<< " size " << stations.size() ); if (stations.size()) { return stations[0]; } return NULL; } // Given a frequency, return the first matching station. FGNavRecord *FGNavList::findStationByFreq( double freq ) { nav_list_type stations = navaids[(int)(freq*100.0 + 0.5)]; SG_LOG( SG_INSTR, SG_DEBUG, "findStationByFreq " << freq << " size " << stations.size() ); if (stations.size()) { return stations[0]; } return NULL; }