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