1 // navlist.cxx -- navaids management class
3 // Written by Curtis Olson, started April 2000.
5 // Copyright (C) 2000 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
28 #include <simgear/debug/logstream.hxx>
29 #include <simgear/misc/sgstream.hxx>
30 #include <simgear/math/sg_geodesy.hxx>
32 #include "navlist.hxx"
35 // Return true if the nav record matches the type
36 static bool isTypeMatch(const FGNavRecord* n, fg_nav_types type)
38 if (type == FG_NAV_ANY) return true;
39 return type == n->type();
44 // FGNavList ------------------------------------------------------------------
46 FGNavList::FGNavList( void )
51 FGNavList::~FGNavList( void )
53 navaids_by_tile.erase( navaids_by_tile.begin(), navaids_by_tile.end() );
54 nav_list_type navlist = navaids.begin()->second;
55 navaids.erase( navaids.begin(), navaids.end() );
59 // load the navaids and build the map
60 bool FGNavList::init()
62 // No need to delete the original navaid structures
63 // since we're using an SGSharedPointer
64 nav_list_type navlist = navaids.begin()->second;
65 navaids.erase( navaids.begin(), navaids.end() );
66 navaids_by_tile.erase( navaids_by_tile.begin(), navaids_by_tile.end() );
67 ident_navaids.erase( ident_navaids.begin(), ident_navaids.end() );
73 // real add a marker beacon
74 static void real_add( nav_map_type &navmap, const int master_index,
77 navmap[master_index].push_back( n );
81 // front end for add a marker beacon
82 static void tile_add( nav_map_type &navmap, FGNavRecord *n )
86 double lon = n->get_lon();
87 double lat = n->get_lat();
89 int lonidx = (int)lon;
90 diff = lon - (double)lonidx;
91 if ( (lon < 0.0) && (fabs(diff) > SG_EPSILON) ) {
94 double lonfrac = lon - (double)lonidx;
97 int latidx = (int)lat;
98 diff = lat - (double)latidx;
99 if ( (lat < 0.0) && (fabs(diff) > SG_EPSILON) ) {
102 double latfrac = lat - (double)latidx;
105 int master_index = lonidx * 1000 + latidx;
106 // cout << "lonidx = " << lonidx << " latidx = " << latidx << " ";
107 // cout << "Master index = " << master_index << endl;
109 // add to the actual bucket
110 real_add( navmap, master_index, n );
112 // if we are close to the edge, add to adjacent buckets so we only
113 // have to search one bucket at run time
115 // there are 8 cases since there are 8 adjacent tiles
117 if ( lonfrac < 0.2 ) {
118 real_add( navmap, master_index - 1000, n );
119 if ( latfrac < 0.2 ) {
120 real_add( navmap, master_index - 1000 - 1, n );
121 } else if ( latfrac > 0.8 ) {
122 real_add( navmap, master_index - 1000 + 1, n );
124 } else if ( lonfrac > 0.8 ) {
125 real_add( navmap, master_index + 1000, n );
126 if ( latfrac < 0.2 ) {
127 real_add( navmap, master_index + 1000 - 1, n );
128 } else if ( latfrac > 0.8 ) {
129 real_add( navmap, master_index + 1000 + 1, n );
131 } else if ( latfrac < 0.2 ) {
132 real_add( navmap, master_index - 1, n );
133 } else if ( latfrac > 0.8 ) {
134 real_add( navmap, master_index + 1, n );
139 // add an entry to the lists
140 bool FGNavList::add( FGNavRecord *n )
142 navaids[n->get_freq()].push_back(n);
143 ident_navaids[n->get_ident()].push_back(n);
144 tile_add( navaids_by_tile, n );
148 FGNavRecord *FGNavList::findByFreq( double freq, double lon, double lat, double elev )
150 const nav_list_type& stations = navaids[(int)(freq*100.0 + 0.5)];
152 SGGeod geod = SGGeod::fromRadM(lon, lat, elev);
153 SGVec3d aircraft = SGVec3d::fromGeod(geod);
154 SG_LOG( SG_INSTR, SG_DEBUG, "findbyFreq " << freq << " size " << stations.size() );
156 return findNavFromList( aircraft, stations );
160 FGNavRecord *FGNavList::findByIdent( const char* ident,
161 const double lon, const double lat )
163 const nav_list_type& stations = ident_navaids[ident];
164 SGGeod geod = SGGeod::fromRad(lon, lat);
165 SGVec3d aircraft = SGVec3d::fromGeod(geod);
166 return findNavFromList( aircraft, stations );
172 // Given an Ident and optional freqency, return the first matching
174 FGNavRecord *FGNavList::findByIdentAndFreq( const char* ident, const double freq )
176 nav_list_type stations = ident_navaids[ident];
177 SG_LOG( SG_INSTR, SG_DEBUG, "findByIdent " << ident<< " size " << stations.size() );
179 // sometimes there can be duplicated idents. If a freq is
180 // specified, use it to refine the search.
181 int f = (int)(freq*100.0 + 0.5);
182 nav_list_const_iterator it, end = stations.end();
183 for ( it = stations.begin(); it != end; ++it ) {
184 if ( f == (*it)->get_freq() ) {
188 } else if (!stations.empty()) {
195 // LOC, ILS, GS, and DME antenna's could potentially be
196 // installed at the opposite end of the runway. So it's not
197 // enough to simply find the closest antenna with the right
198 // frequency. We need the closest antenna with the right
199 // frequency that is most oriented towards us. (We penalize
200 // stations that are facing away from us by adding 5000 meters
201 // which is further than matching stations would ever be
202 // placed from each other. (Do the expensive check only for
203 // directional atennas and only when there is a chance it is
204 // the closest station.)
206 static bool penaltyForNav(FGNavRecord* aNav, const SGVec3d &aPos)
208 switch (aNav->type()) {
209 case FGPositioned::ILS:
210 case FGPositioned::LOC:
211 case FGPositioned::GS:
213 // case FGPositioned::DME: we can't get the heading for a DME transmitter, oops
219 double hdg_deg = 0.0;
220 if (aNav->type() == FGPositioned::GS) {
221 int tmp = (int)(aNav->get_multiuse() / 1000.0);
222 hdg_deg = aNav->get_multiuse() - (tmp * 1000);
224 hdg_deg = aNav->get_multiuse();
227 double az1 = 0.0, az2 = 0.0, s = 0.0;
228 SGGeod geod = SGGeod::fromCart(aPos);
229 geo_inverse_wgs_84( geod, aNav->geod(), &az1, &az2, &s);
232 if ( az1 > 180.0) az1 -= 360.0;
233 if ( az1 < -180.0) az1 += 360.0;
235 return fabs(az1) > 90.0;
238 // Given a point and a list of stations, return the closest one to the
240 FGNavRecord *FGNavList::findNavFromList( const SGVec3d &aircraft,
241 const nav_list_type &stations )
243 FGNavRecord *nav = NULL;
244 double d2; // in meters squared
246 = FG_NAV_MAX_RANGE*SG_NM_TO_METER*FG_NAV_MAX_RANGE*SG_NM_TO_METER;
248 nav_list_const_iterator it;
249 nav_list_const_iterator end = stations.end();
250 // find the closest station within a sensible range (FG_NAV_MAX_RANGE)
251 for ( it = stations.begin(); it != end; ++it ) {
252 FGNavRecord *station = *it;
253 // cout << "testing " << current->get_ident() << endl;
254 d2 = distSqr(station->get_cart(), aircraft);
255 if ( d2 < min_dist && penaltyForNav(station, aircraft))
257 double dist = sqrt(d2);
258 d2 = (dist + 5000) * (dist + 5000);
261 if ( d2 < min_dist ) {
271 // returns the closest entry to the give lon/lat/elev
272 FGNavRecord *FGNavList::findClosest( double lon_rad, double lat_rad,
273 double elev_m, fg_nav_types type)
275 FGNavRecord *result = NULL;
278 double lon_deg = lon_rad * SG_RADIANS_TO_DEGREES;
279 double lat_deg = lat_rad * SG_RADIANS_TO_DEGREES;
280 int lonidx = (int)lon_deg;
281 diff = lon_deg - (double)lonidx;
282 if ( (lon_deg < 0.0) && (fabs(diff) > SG_EPSILON) ) {
287 int latidx = (int)lat_deg;
288 diff = lat_deg - (double)latidx;
289 if ( (lat_deg < 0.0) && (fabs(diff) > SG_EPSILON) ) {
294 int master_index = lonidx * 1000 + latidx;
296 const nav_list_type& navs = navaids_by_tile[ master_index ];
297 // cout << "Master index = " << master_index << endl;
298 // cout << "beacon search length = " << beacons.size() << endl;
300 nav_list_const_iterator current = navs.begin();
301 nav_list_const_iterator last = navs.end();
303 SGGeod geod = SGGeod::fromRadM(lon_rad, lat_rad, elev_m);
304 SGVec3d aircraft = SGVec3d::fromGeod(geod);
306 double min_dist = 999999999.0;
308 for ( ; current != last ; ++current ) {
309 if(isTypeMatch(*current, type)) {
310 // cout << " testing " << (*current)->get_ident() << endl;
312 double d = distSqr((*current)->get_cart(), aircraft);
313 // cout << " distance = " << d << " ("
314 // << FG_ILS_DEFAULT_RANGE * SG_NM_TO_METER
315 // * FG_ILS_DEFAULT_RANGE * SG_NM_TO_METER
318 // cout << " range = " << sqrt(d) << endl;
320 if ( d < min_dist ) {
327 // cout << "lon = " << lon << " lat = " << lat
328 // << " closest beacon = " << sqrt( min_dist ) << endl;
333 // Given a frequency, return the first matching station.
334 FGNavRecord *FGNavList::findStationByFreq( double freq )
336 const nav_list_type& stations = navaids[(int)(freq*100.0 + 0.5)];
338 SG_LOG( SG_INSTR, SG_DEBUG, "findStationByFreq " << freq << " size " << stations.size() );
340 if (!stations.empty()) {
348 // FGTACANList ----------------------------------------------------------------
350 FGTACANList::FGTACANList( void )
355 FGTACANList::~FGTACANList( void )
360 bool FGTACANList::init()
366 // add an entry to the lists
367 bool FGTACANList::add( FGTACANRecord *c )
369 ident_channels[c->get_channel()].push_back(c);
374 // Given a TACAN Channel return the first matching frequency
375 FGTACANRecord *FGTACANList::findByChannel( const string& channel )
377 const tacan_list_type& stations = ident_channels[channel];
378 SG_LOG( SG_INSTR, SG_DEBUG, "findByChannel " << channel<< " size " << stations.size() );
380 if (!stations.empty()) {