src/ATC/ATCmgr.cxx

   1 // ATCmgr.cxx - Implementation of FGATCMgr - a global Flightgear ATC manager.
   2 //
   3 // Written by David Luff, started February 2002.
   4 //
   5 // Copyright (C) 2002  David C Luff - david.luff@nottingham.ac.uk
   6 //
   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.
  11 //
  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.
  16 //
  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., 675 Mass Ave, Cambridge, MA 02139, USA.
  20
  21 //#include <Time/event.hxx>
  22
  23 #include <simgear/misc/sg_path.hxx>
  24 #include <simgear/debug/logstream.hxx>
  25 #include <Airports/simple.hxx>
  26
  27 #include "ATCmgr.hxx"
  28 #include "commlist.hxx"
  29 #include "ATCdisplay.hxx"
  30 #include "ATCDialog.hxx"
  31 #include "ATCutils.hxx"
  32
  33 /*
  34 // periodic radio station search wrapper
  35 static void fgATCSearch( void ) {
  36         globals->get_ATC_mgr()->Search();
  37 }
  38 */ //This wouldn't compile - including Time/event.hxx breaks it :-(
  39
  40 AirportATC::AirportATC() :
  41     lon(0.0),
  42     lat(0.0),
  43     elev(0.0),
  44     atis_freq(0.0),
  45     atis_active(false),
  46     tower_freq(0.0),
  47     tower_active(false),
  48     ground_freq(0.0),
  49     ground_active(false),
  50     set_by_AI(false),
  51         numAI(0)
  52 {
  53     set_by_comm[0] = false;
  54         set_by_comm[1] = false;
  55 }
  56
  57 FGATCMgr::FGATCMgr() {
  58         comm_ident[0] = "";
  59         comm_ident[1] = "";
  60         last_comm_ident[0] = "";
  61         last_comm_ident[1] = "";
  62         approach_ident = "";
  63         last_in_range = false;
  64         comm_type[0] = INVALID;
  65         comm_type[1] = INVALID;
  66         comm_atc_ptr[0] = NULL;
  67         comm_atc_ptr[1] = NULL;
  68         comm_valid[0] = false;
  69         comm_valid[1] = false;
  70
  71         initDone = false;
  72 }
  73
  74 FGATCMgr::~FGATCMgr() {
  75         delete v1;
  76 }
  77
  78 void FGATCMgr::bind() {
  79 }
  80
  81 void FGATCMgr::unbind() {
  82 }
  83
  84 void FGATCMgr::init() {
  85         comm_node[0] = fgGetNode("/radios/comm[0]/frequencies/selected-mhz", true);
  86         comm_node[1] = fgGetNode("/radios/comm[1]/frequencies/selected-mhz", true);
  87         lon_node = fgGetNode("/position/longitude-deg", true);
  88         lat_node = fgGetNode("/position/latitude-deg", true);
  89         elev_node = fgGetNode("/position/altitude-ft", true);
  90         atc_list_itr = atc_list.begin();
  91
  92         // Search for connected ATC stations once per 0.8 seconds or so
  93         // global_events.Register( "fgATCSearch()", fgATCSearch,
  94         //                  fgEVENT::FG_EVENT_READY, 800);
  95         // For some reason the above doesn't compile - including Time/event.hxx stops compilation.
  96
  97         // Initialise the frequency search map
  98     current_commlist = new FGCommList;
  99     SGPath p_comm( globals->get_fg_root() );
 100     current_commlist->init( p_comm );
 101
 102 #ifdef ENABLE_AUDIO_SUPPORT
 103         // Load all available voices.
 104         // For now we'll do one hardwired one
 105
 106         v1 = new FGATCVoice;
 107         voiceOK = v1->LoadVoice("default");
 108         voice = true;
 109
 110         /* I've loaded the voice even if /sim/sound/audible is false
 111         *  since I know no way of forcing load of the voice if the user
 112         *  subsequently switches /sim/sound/audible to true. */
 113 #else
 114         voice = false;
 115 #endif
 116
 117         // Initialise the ATC Dialogs
 118         //cout << "Initing Transmissions..." << endl;
 119     SG_LOG(SG_ATC, SG_INFO, "  ATC Transmissions");
 120     current_transmissionlist = new FGTransmissionList;
 121     SGPath p_transmission( globals->get_fg_root() );
 122     p_transmission.append( "ATC/default.transmissions" );
 123     current_transmissionlist->init( p_transmission );
 124         //cout << "Done Transmissions" << endl;
 125
 126     SG_LOG(SG_ATC, SG_INFO, "  ATC Dialog System");
 127     current_atcdialog = new FGATCDialog;
 128     current_atcdialog->Init();
 129
 130         ATCDialogInit();
 131
 132         // DCL - testing
 133         //current_atcdialog->add_entry( "EGNX", "Request vectoring for approach", "Request Vectors" );
 134         //current_atcdialog->add_entry( "EGNX", "Mayday, Mayday", "Declare Emergency" );
 135
 136         initDone = true;
 137 }
 138
 139 void FGATCMgr::update(double dt) {
 140         if(!initDone) {
 141                 init();
 142                 SG_LOG(SG_ATC, SG_WARN, "Warning - ATCMgr::update(...) called before ATCMgr::init()");
 143         }
 144
 145         //cout << "Entering update..." << endl;
 146         //Traverse the list of active stations.
 147         //Only update one class per update step to avoid the whole ATC system having to calculate between frames.
 148         //Eventually we should only update every so many steps.
 149         //cout << "In FGATCMgr::update - atc_list.size = " << atc_list.size() << '\n';
 150         if(atc_list.size()) {
 151                 if(atc_list_itr == atc_list.end()) {
 152                         atc_list_itr = atc_list.begin();
 153                 }
 154                 //cout << "Updating " << (*atc_list_itr)->get_ident() << ' ' << (*atc_list_itr)->GetType() << '\n';
 155                 //cout << "Freq = " << (*atc_list_itr)->get_freq() << '\n';
 156                 (*atc_list_itr)->Update(dt * atc_list.size());
 157                 //cout << "Done ATC update..." << endl;
 158                 ++atc_list_itr;
 159         }
 160
 161         // Search the tuned frequencies every now and then - this should be done with the event scheduler
 162         static int i = 0;
 163         if(i == 7) {
 164                 //cout << "About to AreaSearch()" << endl;
 165                 AreaSearch();
 166         }
 167         if(i == 15) {
 168                 //cout << "About to search(1)" << endl;
 169                 FreqSearch(1);
 170         }
 171         if(i == 30) {
 172                 //cout << "About to search(2)" << endl;
 173                 FreqSearch(2);
 174                 i = 0;
 175         }
 176         ++i;
 177
 178         //cout << "comm1 type = " << comm_type[0] << '\n';
 179         //cout << "Leaving update..." << endl;
 180 }
 181
 182
 183 // Returns frequency in KHz - should I alter this to return in MHz?
 184 unsigned short int FGATCMgr::GetFrequency(string ident, atc_type tp) {
 185         ATCData test;
 186         bool ok = current_commlist->FindByCode(ident, test, tp);
 187         return(ok ? test.freq : 0);
 188 }
 189
 190
 191 // Register the fact that the AI system wants to activate an airport
 192 // Might need more sophistication in this in the future - eg registration by aircraft call-sign.
 193 bool FGATCMgr::AIRegisterAirport(string ident) {
 194         SG_LOG(SG_ATC, SG_BULK, "AI registered airport " << ident << " with the ATC system");
 195         if(airport_atc_map.find(ident) != airport_atc_map.end()) {
 196                 airport_atc_map[ident]->set_by_AI = true;
 197                 airport_atc_map[ident]->numAI++;
 198                 return(true);
 199         } else {
 200                 FGAirport ap;
 201                 if(dclFindAirportID(ident, &ap)) {
 202                         //cout << "ident = " << ident << '\n';
 203                         AirportATC *a = new AirportATC;
 204                         // I'm not entirely sure that this AirportATC structure business is actually needed - it just duplicates what we can find out anyway!
 205                         a->lon = ap.longitude;
 206                         a->lat = ap.latitude;
 207                         a->elev = ap.elevation;
 208                         a->atis_freq = GetFrequency(ident, ATIS);
 209                         //cout << "ATIS freq = " << a->atis_freq << '\n';
 210                         a->atis_active = false;
 211                         a->tower_freq = GetFrequency(ident, TOWER);
 212                         //cout << "Tower freq = " << a->tower_freq << '\n';
 213                         a->tower_active = false;
 214                         a->ground_freq = GetFrequency(ident, GROUND);
 215                         //cout << "Ground freq = " << a->ground_freq << '\n';
 216                         a->ground_active = false;
 217                         // TODO - some airports will have a tower/ground frequency but be inactive overnight.
 218                         a->set_by_AI = true;
 219                         a->numAI = 1;
 220                         airport_atc_map[ident] = a;
 221                         return(true);
 222                 }
 223         }
 224         return(false);
 225 }
 226
 227
 228 // Register the fact that the comm radio is tuned to an airport
 229 // Channel is zero based
 230 bool FGATCMgr::CommRegisterAirport(string ident, int chan) {
 231         SG_LOG(SG_ATC, SG_BULK, "Comm channel " << chan << " registered airport " << ident);
 232         if(airport_atc_map.find(ident) != airport_atc_map.end()) {
 233                 //cout << "IN MAP - flagging set by comm..." << endl;
 234                 if(chan == 0) {
 235                         airport_atc_map[ident]->set_by_comm[0] = true;
 236                 } else if(chan == 1) {
 237                         airport_atc_map[ident]->set_by_comm[1] = true;
 238                 } else {
 239                         SG_LOG(SG_ATC, SG_ALERT, "COMM CHANNEL NOT 0 OR 1 IN FGATCMGR!");
 240                         // Just register both and accept the fact that this ATC will probably never get removed!
 241                         airport_atc_map[ident]->set_by_comm[0] = true;
 242                         airport_atc_map[ident]->set_by_comm[1] = true;
 243                 }
 244                 return(true);
 245         } else {
 246                 //cout << "NOT IN MAP - creating new..." << endl;
 247                 FGAirport ap;
 248                 if(dclFindAirportID(ident, &ap)) {
 249                         AirportATC *a = new AirportATC;
 250                         // I'm not entirely sure that this AirportATC structure business is actually needed - it just duplicates what we can find out anyway!
 251                         a->lon = ap.longitude;
 252                         a->lat = ap.latitude;
 253                         a->elev = ap.elevation;
 254                         a->atis_freq = GetFrequency(ident, ATIS);
 255                         a->atis_active = false;
 256                         a->tower_freq = GetFrequency(ident, TOWER);
 257                         a->tower_active = false;
 258                         a->ground_freq = GetFrequency(ident, GROUND);
 259                         a->ground_active = false;
 260                         // TODO - some airports will have a tower/ground frequency but be inactive overnight.
 261                         a->set_by_AI = false;
 262                         a->numAI = 0;
 263                         if(chan == 0) {
 264                                 a->set_by_comm[0] = true;
 265                         } else if(chan == 1) {
 266                                 a->set_by_comm[1] = true;
 267                         } else {
 268                                 SG_LOG(SG_ATC, SG_ALERT, "COMM CHANNEL NOT 1 OR 2 IN FGATCMGR!");
 269                                 // Just register both and accept the fact that this ATC will probably never get removed!
 270                                 a->set_by_comm[0] = true;
 271                                 a->set_by_comm[1] = true;
 272                         }
 273                         airport_atc_map[ident] = a;
 274                         return(true);
 275                 }
 276         }
 277         return(false);
 278 }
 279
 280
 281 // Remove from list only if not needed by the AI system or the other comm channel
 282 // Note that chan is zero based.
 283 void FGATCMgr::CommRemoveFromList(const char* id, atc_type tp, int chan) {
 284         SG_LOG(SG_ATC, SG_BULK, "CommRemoveFromList called for airport " << id << " by channel " << chan);
 285         if(airport_atc_map.find((string)id) != airport_atc_map.end()) {
 286                 AirportATC* a = airport_atc_map[(string)id];
 287                 //cout << "In CommRemoveFromList, a->ground_freq = " << a->ground_freq << endl;
 288                 if(a->set_by_AI) {
 289                         // Don't remove
 290                         FGATC* aptr = GetATCPointer((string)id, tp);
 291                         switch(chan) {
 292                         case 0:
 293                                 //cout << "chan 1\n";
 294                                 a->set_by_comm[0] = false;
 295                                 if(!a->set_by_comm[1]) {
 296                                         //cout << "not set by comm2\n";
 297                                         if(aptr != NULL) {
 298                                                 //cout << "Got pointer\n";
 299                                                 aptr->SetNoDisplay();
 300                                                 //cout << "Setting no display...\n";
 301                                         } else {
 302                                                 //cout << "Not got pointer\n";
 303                                         }
 304                                 }
 305                                 break;
 306                         case 1:
 307                                 a->set_by_comm[1] = false;
 308                                 if(!a->set_by_comm[0]) {
 309                                         if(aptr != NULL) {
 310                                                 aptr->SetNoDisplay();
 311                                                 //cout << "Setting no display...\n";
 312                                         }
 313                                 }
 314                                 break;
 315                         }
 316                         airport_atc_map[(string)id] = a;
 317                         return;
 318                 } else {
 319                         switch(chan) {
 320                         case 0:
 321                                 a->set_by_comm[0] = false;
 322                                 // Remove only if not also set by the other comm channel
 323                                 if(!a->set_by_comm[1]) {
 324                                         RemoveFromList(id, tp);
 325                                 }
 326                                 break;
 327                         case 1:
 328                                 a->set_by_comm[1] = false;
 329                                 if(!a->set_by_comm[0]) {
 330                                         RemoveFromList(id, tp);
 331                                 }
 332                                 break;
 333                         }
 334                 }
 335         }
 336 }
 337
 338
 339 // Remove from list - should only be called from above or similar
 340 // This function *will* remove it from the list regardless of who else might want it.
 341 void FGATCMgr::RemoveFromList(const char* id, atc_type tp) {
 342         //cout << "Requested type = " << tp << '\n';
 343         //cout << "id = " << id << '\n';
 344         atc_list_itr = atc_list.begin();
 345         while(atc_list_itr != atc_list.end()) {
 346                 //cout << "type = " << (*atc_list_itr)->GetType() << '\n';
 347                 //cout << "Ident = " << (*atc_list_itr)->get_ident() << '\n';
 348                 if( (!strcmp((*atc_list_itr)->get_ident(), id))
 349                         && ((*atc_list_itr)->GetType() == tp) ) {
 350                                 //Before removing it stop it transmitting!!
 351                                 //cout << "OBLITERATING FROM LIST!!!\n";
 352                                 (*atc_list_itr)->SetNoDisplay();
 353                                 (*atc_list_itr)->Update(0.00833);
 354                                 delete (*atc_list_itr);
 355                                 atc_list_itr = atc_list.erase(atc_list_itr);
 356                                 break;
 357                         }  // Note that that can upset where we are in the list but that doesn't really matter
 358                 ++atc_list_itr;
 359         }
 360 }
 361
 362
 363 // Find in list - return a currently active ATC pointer given ICAO code and type
 364 // Return NULL if the given service is not in the list
 365 // - *** THE CALLING FUNCTION MUST CHECK FOR THIS ***
 366 FGATC* FGATCMgr::FindInList(const char* id, atc_type tp) {
 367         atc_list_itr = atc_list.begin();
 368         while(atc_list_itr != atc_list.end()) {
 369                 if( (!strcmp((*atc_list_itr)->get_ident(), id))
 370                 && ((*atc_list_itr)->GetType() == tp) ) {
 371                         return(*atc_list_itr);
 372                 }       // Note that that can upset where we are in the list but that shouldn't really matter
 373                 ++atc_list_itr;
 374         }
 375         // If we get here it's not in the list
 376         return(NULL);
 377 }
 378
 379 // Returns true if the airport is found in the map
 380 bool FGATCMgr::GetAirportATCDetails(string icao, AirportATC* a) {
 381         if(airport_atc_map.find(icao) != airport_atc_map.end()) {
 382                 *a = *airport_atc_map[icao];
 383                 return(true);
 384         } else {
 385                 return(false);
 386         }
 387 }
 388
 389
 390 // Return a pointer to a given sort of ATC at a given airport and activate if necessary
 391 // Returns NULL if service doesn't exist - calling function should check for this.
 392 // We really ought to make this private and call it from the CommRegisterAirport / AIRegisterAirport functions
 393 // - at the moment all these GetATC... functions exposed are just too complicated.
 394 FGATC* FGATCMgr::GetATCPointer(string icao, atc_type type) {
 395         if(airport_atc_map.find(icao) == airport_atc_map.end()) {
 396                 return NULL;
 397         }
 398         AirportATC *a = airport_atc_map[icao];
 399         //cout << "a->lon = " << a->lon << '\n';
 400         //cout << "a->elev = " << a->elev << '\n';
 401         //cout << "a->tower_freq = " << a->tower_freq << '\n';
 402         switch(type) {
 403         case TOWER:
 404                 if(a->tower_active) {
 405                         // Get the pointer from the list
 406                         return(FindInList(icao.c_str(), type));
 407                 } else {
 408                         ATCData data;
 409                         if(current_commlist->FindByFreq(a->lon, a->lat, a->elev, a->tower_freq, &data, TOWER)) {
 410                                 FGTower* t = new FGTower;
 411                                 t->SetData(&data);
 412                                 atc_list.push_back(t);
 413                                 a->tower_active = true;
 414                                 airport_atc_map[icao] = a;
 415                                 t->Init();
 416                                 return(t);
 417                         } else {
 418                                 SG_LOG(SG_ATC, SG_ALERT, "ERROR - tower that should exist in FGATCMgr::GetATCPointer for airport " << icao << " not found");
 419                         }
 420                 }
 421                 break;
 422         case APPROACH:
 423                 break;
 424         case ATIS:
 425                 SG_LOG(SG_ATC, SG_ALERT, "ERROR - ATIS station should not be requested from FGATCMgr::GetATCPointer");
 426                 break;
 427         case GROUND:
 428                 //cout << "IN CASE GROUND" << endl;
 429                 if(a->ground_active) {
 430                         // Get the pointer from the list
 431                         return(FindInList(icao.c_str(), type));
 432                 } else {
 433                         ATCData data;
 434                         if(current_commlist->FindByFreq(a->lon, a->lat, a->elev, a->ground_freq, &data, GROUND)) {
 435                                 FGGround* g = new FGGround;
 436                                 g->SetData(&data);
 437                                 atc_list.push_back(g);
 438                                 a->ground_active = true;
 439                                 airport_atc_map[icao] = a;
 440                                 g->Init();
 441                                 return(g);
 442                         } else {
 443                                 SG_LOG(SG_ATC, SG_ALERT, "ERROR - ground control that should exist in FGATCMgr::GetATCPointer for airport " << icao << " not found");
 444                         }
 445                 }
 446                 break;
 447                 case INVALID:
 448                 break;
 449                 case ENROUTE:
 450                 break;
 451                 case DEPARTURE:
 452                 break;
 453         }
 454
 455         SG_LOG(SG_ATC, SG_ALERT, "ERROR IN FGATCMgr - reached end of GetATCPointer");
 456
 457         return(NULL);
 458 }
 459
 460 // Return a pointer to an appropriate voice for a given type of ATC
 461 // creating the voice if necessary - ie. make sure exactly one copy
 462 // of every voice in use exists in memory.
 463 //
 464 // TODO - in the future this will get more complex and dole out country/airport
 465 // specific voices, and possible make sure that the same voice doesn't get used
 466 // at different airports in quick succession if a large enough selection are available.
 467 FGATCVoice* FGATCMgr::GetVoicePointer(atc_type type) {
 468         // TODO - implement me better - maintain a list of loaded voices and other voices!!
 469         if(voice) {
 470                 switch(type) {
 471                 case ATIS:
 472                         if(voiceOK) {
 473                                 return(v1);
 474                         }
 475                 case TOWER:
 476                         return(NULL);
 477                 case APPROACH:
 478                         return(NULL);
 479                 case GROUND:
 480                         return(NULL);
 481                 default:
 482                         return(NULL);
 483                 }
 484                 return(NULL);
 485         } else {
 486                 return(NULL);
 487         }
 488 }
 489
 490 // Display a dialog box with options relevant to the currently tuned ATC service.
 491 void FGATCMgr::doPopupDialog() {
 492         ATCDoDialog(comm_type[0]);      // FIXME - currently hardwired to comm1
 493 }
 494
 495 // Search for ATC stations by frequency
 496 void FGATCMgr::FreqSearch(int channel) {
 497         int chan = channel - 1;         // Convert to zero-based for the arrays
 498
 499         ATCData data;
 500         double freq = comm_node[chan]->getDoubleValue();
 501         lon = lon_node->getDoubleValue();
 502         lat = lat_node->getDoubleValue();
 503         elev = elev_node->getDoubleValue() * SG_FEET_TO_METER;
 504
 505         // Query the data store and get the closest match if any
 506         if(current_commlist->FindByFreq(lon, lat, elev, freq, &data)) {
 507                 // We have a match
 508                 // What's the logic?
 509                 // If this channel not previously valid then easy - add ATC to list
 510                 // If this channel was valid then - Have we tuned to a different service?
 511                 // If so - de-register one and add the other
 512                 if(comm_valid[chan]) {
 513                         if((comm_ident[chan] == data.ident) && (comm_type[chan] == data.type)) {
 514                                 // Then we're still tuned into the same service so do nought and return
 515                                 return;
 516                         } else {
 517                                 // Something's changed - either the location or the service type
 518                                 // We need to feed the channel in so we're not removing it if we're also tuned in on the other channel
 519                                 CommRemoveFromList(comm_ident[chan], comm_type[chan], chan);
 520                         }
 521                 }
 522                 // At this point we can assume that we need to add the service.
 523                 comm_ident[chan] = (data.ident).c_str();
 524                 comm_type[chan] = data.type;
 525                 comm_x[chan] = (double)data.x;
 526                 comm_y[chan] = (double)data.y;
 527                 comm_z[chan] = (double)data.z;
 528                 comm_lon[chan] = (double)data.lon;
 529                 comm_lat[chan] = (double)data.lat;
 530                 comm_elev[chan] = (double)data.elev;
 531                 comm_valid[chan] = true;
 532
 533                 // This was a switch-case statement but the compiler didn't like the new variable creation with it.
 534                 if(comm_type[chan] == ATIS) {
 535                         CommRegisterAirport(comm_ident[chan], chan);
 536                         FGATC* app = FindInList(comm_ident[chan], TOWER);
 537                         if(app != NULL) {
 538                                 // The station is already in the ATC list
 539                                 //cout << "In list - flagging SetDisplay..." << endl;
 540                                 app->SetDisplay();
 541                         } else {
 542                                 // Generate the station and put in the ATC list
 543                                 //cout << "Not in list - generating..." << endl;
 544                                 FGATIS* a = new FGATIS;
 545                                 a->SetData(&data);
 546                                 comm_atc_ptr[chan] = a;
 547                                 a->SetDisplay();
 548                                 //a->Init();
 549                                 atc_list.push_back(a);
 550                         }
 551                 } else if (comm_type[chan] == TOWER) {
 552                         CommRegisterAirport(comm_ident[chan], chan);
 553                         //cout << "Done (TOWER)" << endl;
 554                         FGATC* app = FindInList(comm_ident[chan], TOWER);
 555                         if(app != NULL) {
 556                                 // The station is already in the ATC list
 557                                 //cout << "In list - flagging SetDisplay..." << endl;
 558                                 app->SetDisplay();
 559                         } else {
 560                                 // Generate the station and put in the ATC list
 561                                 //cout << "Not in list - generating..." << endl;
 562                                 FGTower* t = new FGTower;
 563                                 t->SetData(&data);
 564                                 comm_atc_ptr[chan] = t;
 565                                 t->SetDisplay();
 566                                 t->Init();
 567                                 atc_list.push_back(t);
 568                         }
 569                 }  else if (comm_type[chan] == GROUND) {
 570                         CommRegisterAirport(comm_ident[chan], chan);
 571                         //cout << "Done (GROUND)" << endl;
 572                         FGATC* app = FindInList(comm_ident[chan], GROUND);
 573                         if(app != NULL) {
 574                                 // The station is already in the ATC list
 575                                 app->SetDisplay();
 576                         } else {
 577                                 // Generate the station and put in the ATC list
 578                                 FGGround* g = new FGGround;
 579                                 g->SetData(&data);
 580                                 comm_atc_ptr[chan] = g;
 581                                 g->SetDisplay();
 582                                 g->Init();
 583                                 atc_list.push_back(g);
 584                         }
 585                 } else if (comm_type[chan] == APPROACH) {
 586                         // We have to be a bit more carefull here since approaches are also searched by area
 587                         CommRegisterAirport(comm_ident[chan], chan);
 588                         //cout << "Done (APPROACH)" << endl;
 589                         FGATC* app = FindInList(comm_ident[chan], APPROACH);
 590                         if(app != NULL) {
 591                                 // The station is already in the ATC list
 592                                 app->AddPlane("Player");
 593                                 app->SetDisplay();
 594                                 comm_atc_ptr[chan] = app;
 595                         } else {
 596                                 // Generate the station and put in the ATC list
 597                                 FGApproach* a = new FGApproach;
 598                                 a->SetData(&data);
 599                                 a->AddPlane("Player");
 600                                 atc_list.push_back(a);
 601                                 comm_atc_ptr[chan] = a;
 602                         }
 603                 }
 604         } else {
 605                 if(comm_valid[chan]) {
 606                         if(comm_type[chan] != APPROACH) {
 607                                 // Currently approaches are removed by Alexander's out-of-range mechanism
 608                                 CommRemoveFromList(comm_ident[chan], comm_type[chan], chan);
 609                         }
 610                         // Note that we *don't* call SetNoDisplay() here because the other comm channel
 611                         // might be tuned into the same station - this is handled by CommRemoveFromList(...)
 612                         comm_type[chan] = INVALID;
 613                         comm_atc_ptr[chan] = NULL;
 614                         comm_valid[chan] = false;
 615                 }
 616         }
 617 }
 618
 619
 620 // Search ATC stations by area in order that we appear 'on the radar'
 621 void FGATCMgr::AreaSearch() {
 622         // Search for Approach stations
 623         comm_list_type approaches;
 624         comm_list_iterator app_itr;
 625
 626         lon = lon_node->getDoubleValue();
 627         lat = lat_node->getDoubleValue();
 628         elev = elev_node->getDoubleValue() * SG_FEET_TO_METER;
 629
 630         // search stations in range
 631         int num_app = current_commlist->FindByPos(lon, lat, elev, 100.0, &approaches, APPROACH);
 632         if (num_app != 0) {
 633                 //cout << num_app << " approaches found in radiostack search !!!!" << endl;
 634
 635                 for(app_itr = approaches.begin(); app_itr != approaches.end(); app_itr++) {
 636
 637                         FGATC* app = FindInList((app_itr->ident).c_str(), app_itr->type);
 638                         if(app != NULL) {
 639                                 // The station is already in the ATC list
 640                                 app->AddPlane("Player");
 641                                 //app->Update();
 642                         } else {
 643                                 // Generate the station and put in the ATC list
 644                                 FGApproach* a = new FGApproach;
 645                                 a->SetData(&(*app_itr));
 646                                 a->AddPlane("Player");
 647                                 //a->Update();
 648                                 atc_list.push_back(a);
 649                         }
 650                 }
 651         }
 652
 653         // remove planes which are out of range
 654         // TODO - I'm not entirely sure that this belongs here.
 655         atc_list_itr = atc_list.begin();
 656         while(atc_list_itr != atc_list.end()) {
 657                 if((*atc_list_itr)->GetType() == APPROACH ) {
 658                         int np = (*atc_list_itr)->RemovePlane();
 659                         // if approach has no planes left remove it from ATC list
 660                         if ( np == 0) {
 661                                 (*atc_list_itr)->SetNoDisplay();
 662                                 (*atc_list_itr)->Update(0.00833);
 663                                 delete (*atc_list_itr);
 664                                 atc_list_itr = atc_list.erase(atc_list_itr);
 665                                 break;     // the other stations will be checked next time
 666                         }
 667                 }
 668                 ++atc_list_itr;
 669         }
 670 }