src/ATC/tower.cxx

   1 // FGTower - a class to provide tower control at towered airports.
   2 //
   3 // Written by David Luff, started March 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 <Main/globals.hxx>
  22 #include <Airports/runways.hxx>
  23 #include <simgear/math/sg_geodesy.hxx>
  24 #include <simgear/debug/logstream.hxx>
  25
  26 #include "tower.hxx"
  27 #include "ATCdisplay.hxx"
  28 #include "ATCmgr.hxx"
  29 #include "ATCutils.hxx"
  30 #include "commlist.hxx"
  31 #include "AILocalTraffic.hxx"
  32
  33 SG_USING_STD(cout);
  34
  35 // TowerPlaneRec
  36
  37 TowerPlaneRec::TowerPlaneRec() :
  38 clearedToLand(false),
  39 clearedToLineUp(false),
  40 clearedToTakeOff(false),
  41 holdShortReported(false),
  42 longFinalReported(false),
  43 longFinalAcknowledged(false),
  44 finalReported(false),
  45 finalAcknowledged(false),
  46 opType(TTT_UNKNOWN),
  47 leg(LEG_UNKNOWN),
  48 isUser(false)
  49 {
  50         plane.callsign = "UNKNOWN";
  51 }
  52
  53 TowerPlaneRec::TowerPlaneRec(PlaneRec p) :
  54 clearedToLand(false),
  55 clearedToLineUp(false),
  56 clearedToTakeOff(false),
  57 holdShortReported(false),
  58 longFinalReported(false),
  59 longFinalAcknowledged(false),
  60 finalReported(false),
  61 finalAcknowledged(false),
  62 opType(TTT_UNKNOWN),
  63 leg(LEG_UNKNOWN),
  64 isUser(false)
  65 {
  66         plane = p;
  67 }
  68
  69 TowerPlaneRec::TowerPlaneRec(Point3D pt) :
  70 clearedToLand(false),
  71 clearedToLineUp(false),
  72 clearedToTakeOff(false),
  73 holdShortReported(false),
  74 longFinalReported(false),
  75 longFinalAcknowledged(false),
  76 finalReported(false),
  77 finalAcknowledged(false),
  78 opType(TTT_UNKNOWN),
  79 leg(LEG_UNKNOWN),
  80 isUser(false)
  81 {
  82         plane.callsign = "UNKNOWN";
  83         pos = pt;
  84 }
  85
  86 TowerPlaneRec::TowerPlaneRec(PlaneRec p, Point3D pt) :
  87 clearedToLand(false),
  88 clearedToLineUp(false),
  89 clearedToTakeOff(false),
  90 holdShortReported(false),
  91 longFinalReported(false),
  92 longFinalAcknowledged(false),
  93 finalReported(false),
  94 finalAcknowledged(false),
  95 opType(TTT_UNKNOWN),
  96 leg(LEG_UNKNOWN),
  97 isUser(false)
  98 {
  99         plane = p;
 100         pos = pt;
 101 }
 102
 103
 104 // FGTower
 105
 106 FGTower::FGTower() {
 107         ATCmgr = globals->get_ATC_mgr();
 108
 109         // Init the property nodes - TODO - need to make sure we're getting surface winds.
 110         wind_from_hdg = fgGetNode("/environment/wind-from-heading-deg", true);
 111         wind_speed_knots = fgGetNode("/environment/wind-speed-kt", true);
 112
 113         holdListItr = holdList.begin();
 114         appListItr = appList.begin();
 115         depListItr = depList.begin();
 116         rwyListItr = rwyList.begin();
 117         circuitListItr = circuitList.begin();
 118         trafficListItr = trafficList.begin();
 119 }
 120
 121 FGTower::~FGTower() {
 122         if(!separateGround) {
 123                 delete ground;
 124         }
 125 }
 126
 127 void FGTower::Init() {
 128     display = false;
 129
 130         // Pointers to user's position
 131         user_lon_node = fgGetNode("/position/longitude-deg", true);
 132         user_lat_node = fgGetNode("/position/latitude-deg", true);
 133         user_elev_node = fgGetNode("/position/altitude-ft", true);
 134         user_hdg_node = fgGetNode("/orientation/heading-deg", true);
 135
 136         // Need some way to initialise rwyOccupied flag correctly if the user is on the runway and to know its the user.
 137         // I'll punt the startup issue for now though!!!
 138         rwyOccupied = false;
 139
 140         // Setup the ground control at this airport
 141         AirportATC a;
 142         //cout << "Tower ident = " << ident << '\n';
 143         if(ATCmgr->GetAirportATCDetails(ident, &a)) {
 144                 if(a.ground_freq) {             // Ground control
 145                         ground = (FGGround*)ATCmgr->GetATCPointer(ident, GROUND);
 146                         separateGround = true;
 147                         if(ground == NULL) {
 148                                 // Something has gone wrong :-(
 149                                 SG_LOG(SG_ATC, SG_WARN, "ERROR - ground has frequency but can't get ground pointer :-(");
 150                                 ground = new FGGround(ident);
 151                                 separateGround = false;
 152                                 ground->Init();
 153                                 if(display) {
 154                                         ground->SetDisplay();
 155                                 } else {
 156                                         ground->SetNoDisplay();
 157                                 }
 158                         }
 159                 } else {
 160                         // Initialise ground anyway to do the shortest path stuff!
 161                         // Note that we're now responsible for updating and deleting this - NOT the ATCMgr.
 162                         ground = new FGGround(ident);
 163                         separateGround = false;
 164                         ground->Init();
 165                         if(display) {
 166                                 ground->SetDisplay();
 167                         } else {
 168                                 ground->SetNoDisplay();
 169                         }
 170                 }
 171         } else {
 172                 SG_LOG(SG_ATC, SG_ALERT, "Unable to find airport details for " << ident << " in FGTower::Init()");
 173                 // Initialise ground anyway to avoid segfault later
 174                 ground = new FGGround(ident);
 175                 separateGround = false;
 176                 ground->Init();
 177                 if(display) {
 178                         ground->SetDisplay();
 179                 } else {
 180                         ground->SetNoDisplay();
 181                 }
 182         }
 183
 184         // Get the airport elevation
 185         aptElev = dclGetAirportElev(ident.c_str()) * SG_FEET_TO_METER;
 186
 187         DoRwyDetails();
 188
 189         // FIXME - this currently assumes use of the active rwy by the user.
 190         rwyOccupied = OnAnyRunway(Point3D(user_lon_node->getDoubleValue(), user_lat_node->getDoubleValue(), 0.0));
 191         if(rwyOccupied) {
 192                 // Assume the user is started at the threshold ready to take-off
 193                 TowerPlaneRec* t = new TowerPlaneRec;
 194                 t->plane.callsign = "Charlie Foxtrot Sierra";   // C-FGFS !!! - fixme - this is a bit hardwired
 195                 t->opType = TTT_UNKNOWN;        // We don't know if the user wants to do circuits or a departure...
 196                 t->leg = TAKEOFF_ROLL;
 197                 t->isUser = true;
 198                 t->planePtr = NULL;
 199                 t->clearedToTakeOff = true;
 200                 rwyList.push_back(t);
 201         }
 202 }
 203
 204 void FGTower::Update(double dt) {
 205         static int ii = 0;      // Counter for spreading the load
 206         int ii_max = 15;
 207         //cout << "T" << flush;
 208         // Each time step, what do we need to do?
 209         // We need to go through the list of outstanding requests and acknowedgements
 210         // and process at least one of them.
 211         // We need to go through the list of planes under our control and check if
 212         // any need to be addressed.
 213         // We need to check for planes not under our control coming within our
 214         // control area and address if necessary.
 215
 216         // TODO - a lot of the below probably doesn't need to be called every frame and should be staggered.
 217
 218         // Sort the arriving planes
 219
 220         // Calculate the eta of each plane to the threshold.
 221         // For ground traffic this is the fastest they can get there.
 222         // For air traffic this is the middle approximation.
 223         if(ii == 1) {
 224                 doThresholdETACalc();
 225         }
 226
 227         // Order the list of traffic as per expected threshold use and flag any conflicts
 228         if(ii == 2) {
 229                 bool conflicts = doThresholdUseOrder();
 230         }
 231
 232         // sortConficts() !!!
 233
 234         // Do one plane from the hold list
 235         if(ii == 4) {
 236                 if(holdList.size()) {
 237                         //cout << "*holdListItr = " << *holdListItr << endl;
 238                         if(holdListItr == holdList.end()) {
 239                                 holdListItr = holdList.begin();
 240                         }
 241                         //cout << "*holdListItr = " << *holdListItr << endl;
 242                         //Process(*holdListItr);
 243                         TowerPlaneRec* t = *holdListItr;
 244                         //cout << "t = " << t << endl;
 245                         if(t->holdShortReported) {
 246                                 double responseTime = 10.0;             // seconds - this should get more sophisticated at some point
 247                                 if(t->clearanceCounter > responseTime) {
 248                                         if(t->nextOnRwy) {
 249                                                 if(rwyOccupied) {
 250                                                         // Do nothing for now - consider acknowloging hold short eventually
 251                                                 } else {
 252                                                         // Lets Roll !!!!
 253                                                         string trns = t->plane.callsign;
 254                                                         //if(departed plane < some threshold in time away) {
 255                                                                 if(0) {         // FIXME
 256                                                                         trns += " line up";
 257                                                                         t->clearedToLineUp = true;
 258                                                                         t->planePtr->RegisterTransmission(3);   // cleared to line-up
 259                                                                         t->leg = TAKEOFF_ROLL;
 260                                                         //} else if(arriving plane < some threshold away) {
 261                                                                 } else if(0) {  // FIXME
 262                                                                         trns += " cleared immediate take-off";
 263                                                                         // TODO - add traffic is... ?
 264                                                                         t->clearedToTakeOff = true;
 265                                                                         t->planePtr->RegisterTransmission(4);   // cleared to take-off - TODO differentiate between immediate and normal take-off
 266                                                                         t->leg = TAKEOFF_ROLL;
 267                                                                 } else {
 268                                                                         trns += " cleared for take-off";
 269                                                                         // TODO - add traffic is... ?
 270                                                                         t->clearedToTakeOff = true;
 271                                                                         t->planePtr->RegisterTransmission(4);   // cleared to take-off
 272                                                                         t->leg = TAKEOFF_ROLL;
 273                                                                 }
 274                                                                 if(display) {
 275                                                                         globals->get_ATC_display()->RegisterSingleMessage(trns, 0);
 276                                                                 }
 277                                                                 t->holdShortReported = false;
 278                                                                 t->clearanceCounter = 0;
 279                                                                 rwyList.push_back(t);
 280                                                                 rwyOccupied = true;
 281                                                                 holdList.erase(holdListItr);
 282                                                                 holdListItr = holdList.begin();
 283                                                 }
 284                                         } else {
 285                                                 // possibly tell him to hold and what position he is?
 286                                         }
 287                                 } else {
 288                                         t->clearanceCounter += (dt * holdList.size() * ii_max);
 289                                 }
 290                         }
 291                         ++holdListItr;
 292                 }
 293         }
 294
 295         // Do the runway list - we'll do the whole runway list since it's important and there'll never be many planes on the rwy at once!!
 296         if(ii == 5) {
 297                 if(rwyOccupied) {
 298                         if(!rwyList.size()) {
 299                                 rwyOccupied = false;
 300                         } else {
 301                                 rwyListItr = rwyList.begin();
 302                                 TowerPlaneRec* t = *rwyListItr;
 303                                 if(t->isUser) {
 304                                         bool on_rwy = OnActiveRunway(Point3D(user_lon_node->getDoubleValue(), user_lat_node->getDoubleValue(), 0.0));
 305                                         // TODO - how do we find the position when it's not the user?
 306                                         if(!on_rwy) {
 307                                                 if((t->opType == INBOUND) || (t->opType == STRAIGHT_IN)) {
 308                                                         rwyList.pop_front();
 309                                                         delete t;
 310                                                         // TODO - tell it to taxi / contact ground / don't delete it etc!
 311                                                 } else if(t->opType == OUTBOUND) {
 312                                                         depList.push_back(t);
 313                                                         rwyList.pop_front();
 314                                                 } else if(t->opType == CIRCUIT) {
 315                                                         circuitList.push_back(t);
 316                                                         rwyList.pop_front();
 317                                                 } else if(t->opType == TTT_UNKNOWN) {
 318                                                         depList.push_back(t);
 319                                                         circuitList.push_back(t);
 320                                                         rwyList.pop_front();
 321                                                 } else {
 322                                                         // HELP - we shouldn't ever get here!!!
 323                                                 }
 324                                         }
 325                                 } // else TODO figure out what to do when it's not the user
 326                         }
 327                 }
 328         }
 329
 330         // do the ciruit list
 331         if(ii == 6) {
 332                 // Clear the constraints - we recalculate here.
 333                 base_leg_pos = 0.0;
 334                 downwind_leg_pos = 0.0;
 335                 crosswind_leg_pos = 0.0;
 336                 if(circuitList.size()) {
 337                         circuitListItr = circuitList.begin();   // TODO - at the moment we're constraining plane 2 based on plane 1 - this won't work for 3 planes in the circuit!!
 338                         TowerPlaneRec* t = *circuitListItr;
 339                         if(t->isUser) {
 340                                 t->pos.setlon(user_lon_node->getDoubleValue());
 341                                 t->pos.setlat(user_lat_node->getDoubleValue());
 342                                 t->pos.setelev(user_elev_node->getDoubleValue());
 343                         } else {
 344                                 // TODO - set/update the position if it's an AI plane
 345                         }
 346                         Point3D tortho = ortho.ConvertToLocal(t->pos);
 347                         if(t->isUser) {
 348                                 // Need to figure out which leg he's on
 349                                 //cout << "rwy.hdg = " << rwy.hdg << " user hdg = " << user_hdg_node->getDoubleValue();
 350                                 double ho = GetAngleDiff_deg(user_hdg_node->getDoubleValue(), rwy.hdg);
 351                                 //cout << " ho = " << ho << '\n';
 352                                 // TODO FIXME - get the wind and convert this to track, or otherwise use track somehow!!!
 353                                 // If it's gusty might need to filter the value, although we are leaving 30 degrees each way leeway!
 354                                 if(abs(ho) < 30) {
 355                                         // could be either takeoff, climbout or landing - check orthopos.y
 356                                         //cout << "tortho.y = " << tortho.y() << '\n';
 357                                         if((tortho.y() < 0) || (t->leg == TURN4) || (t->leg == FINAL)) {
 358                                                 t->leg = FINAL;
 359                                                 //cout << "Final\n";
 360                                         } else {
 361                                                 t->leg = CLIMBOUT;      // TODO - check elev wrt. apt elev to differentiate takeoff roll and climbout
 362                                                 //cout << "Climbout\n";
 363                                                 // If it's the user we may be unsure of his/her intentions.
 364                                                 // (Hopefully the AI planes won't try confusing the sim!!!)
 365                                                 if(t->opType == TTT_UNKNOWN) {
 366                                                         if(tortho.y() > 5000) {
 367                                                                 // 5 km out from threshold - assume it's a departure
 368                                                                 t->opType = OUTBOUND;
 369                                                                 // Since we are unknown operation we should be in depList already.
 370                                                                 circuitList.erase(circuitListItr);
 371                                                                 circuitListItr = circuitList.begin();
 372                                                         }
 373                                                 } else if(t->opType == CIRCUIT) {
 374                                                         if(tortho.y() > 10000) {
 375                                                                 // 10 km out - assume the user has abandoned the circuit!!
 376                                                                 t->opType = OUTBOUND;
 377                                                                 depList.push_back(t);
 378                                                                 circuitList.erase(circuitListItr);
 379                                                                 circuitListItr = circuitList.begin();
 380                                                         }
 381                                                 }
 382                                         }
 383                                 } else if(abs(ho) < 60) {
 384                                         // turn1 or turn 4
 385                                         // TODO - either fix or doublecheck this hack by looking at heading and pattern direction
 386                                         if((t->leg == CLIMBOUT) || (t->leg == TURN1)) {
 387                                                 t->leg = TURN1;
 388                                                 //cout << "Turn1\n";
 389                                         } else {
 390                                                 t->leg = TURN4;
 391                                                 //cout << "Turn4\n";
 392                                         }
 393                                 } else if(abs(ho) < 120) {
 394                                         // crosswind or base
 395                                         // TODO - either fix or doublecheck this hack by looking at heading and pattern direction
 396                                         if((t->leg == TURN1) || (t->leg == CROSSWIND)) {
 397                                                 t->leg = CROSSWIND;
 398                                                 //cout << "Crosswind\n";
 399                                         } else {
 400                                                 t->leg = BASE;
 401                                                 //cout << "Base\n";
 402                                         }
 403                                 } else if(abs(ho) < 150) {
 404                                         // turn2 or turn 3
 405                                         // TODO - either fix or doublecheck this hack by looking at heading and pattern direction
 406                                         if((t->leg == CROSSWIND) || (t->leg == TURN2)) {
 407                                                 t->leg = TURN2;
 408                                                 //cout << "Turn2\n";
 409                                         } else {
 410                                                 t->leg = TURN3;
 411                                                 //cout << "Turn3\n";
 412                                         }
 413                                 } else {
 414                                         // downwind
 415                                         t->leg = DOWNWIND;
 416                                         //cout << "Downwind\n";
 417                                 }
 418                         } else {
 419                                 t->leg = t->planePtr->GetLeg();
 420                         }
 421                         switch(t->leg) {
 422                         case FINAL:
 423                                 // Base leg must be at least as far out as the plane is - actually possibly not necessary for separation, but we'll use that for now.
 424                                 base_leg_pos = tortho.y();
 425                                 //cout << "base_leg_pos = " << base_leg_pos << '\n';
 426                                 break;
 427                         case TURN4:
 428                                 // Fall through to base
 429                         case BASE:
 430                                 base_leg_pos = tortho.y();
 431                                 //cout << "base_leg_pos = " << base_leg_pos << '\n';
 432                                 break;
 433                         case TURN3:
 434                                 // Fall through to downwind
 435                         case DOWNWIND:
 436                                 // Only have the downwind leg pos as turn-to-base constraint if more negative than we already have.
 437                                 base_leg_pos = (tortho.y() < base_leg_pos ? tortho.y() : base_leg_pos);
 438                                 //cout << "base_leg_pos = " << base_leg_pos;
 439                                 downwind_leg_pos = tortho.x();          // Assume that a following plane can simply be constrained by the immediately in front downwind plane
 440                                 //cout << " downwind_leg_pos = " << downwind_leg_pos << '\n';
 441                                 break;
 442                         case TURN2:
 443                                 // Fall through to crosswind
 444                         case CROSSWIND:
 445                                 crosswind_leg_pos = tortho.y();
 446                                 //cout << "crosswind_leg_pos = " << crosswind_leg_pos << '\n';
 447                                 break;
 448                         case TURN1:
 449                                 // Fall through to climbout
 450                         case CLIMBOUT:
 451                                 // Only use current by constraint as largest
 452                                 crosswind_leg_pos = (tortho.y() > crosswind_leg_pos ? tortho.y() : crosswind_leg_pos);
 453                                 //cout << "crosswind_leg_pos = " << crosswind_leg_pos << '\n';
 454                                 break;
 455                         case TAKEOFF_ROLL:
 456                                 break;
 457                         case LEG_UNKNOWN:
 458                                 break;
 459                         case LANDING_ROLL:
 460                                 break;
 461                         default:
 462                                 break;
 463                         }
 464                 }
 465         }
 466
 467         doCommunication();
 468
 469         if(!separateGround) {
 470                 // The display stuff might have to get more clever than this when not separate
 471                 // since the tower and ground might try communicating simultaneously even though
 472                 // they're mean't to be the same contoller/frequency!!
 473                 if(display) {
 474                         ground->SetDisplay();
 475                 } else {
 476                         ground->SetNoDisplay();
 477                 }
 478                 ground->Update(dt);
 479         }
 480
 481         ++ii;
 482         // How big should ii get - ie how long should the update cycle interval stretch?
 483         if(ii >= ii_max) {
 484                 ii = 0;
 485         }
 486 }
 487
 488
 489 // Returns true if positions of crosswind/downwind/base leg turns should be constrained by previous traffic
 490 // plus the constraint position as a rwy orientated orthopos (meters)
 491 bool FGTower::GetCrosswindConstraint(double& cpos) {
 492         if(crosswind_leg_pos != 0.0) {
 493                 cpos = crosswind_leg_pos;
 494                 return(true);
 495         } else {
 496                 cpos = 0.0;
 497                 return(false);
 498         }
 499 }
 500 bool FGTower::GetDownwindConstraint(double& dpos) {
 501         if(downwind_leg_pos != 0.0) {
 502                 dpos = downwind_leg_pos;
 503                 return(true);
 504         } else {
 505                 dpos = 0.0;
 506                 return(false);
 507         }
 508 }
 509 bool FGTower::GetBaseConstraint(double& bpos) {
 510         if(base_leg_pos != 0.0) {
 511                 bpos = base_leg_pos;
 512                 return(true);
 513         } else {
 514                 bpos = 0.0;
 515                 return(false);
 516         }
 517 }
 518
 519
 520 // Figure out which runways are active.
 521 // For now we'll just be simple and do one active runway - eventually this will get much more complex
 522 // This is a private function - public interface to the results of this is through GetActiveRunway
 523 void FGTower::DoRwyDetails() {
 524         //cout << "GetRwyDetails called" << endl;
 525
 526         // Based on the airport-id and wind get the active runway
 527
 528         //wind
 529         double hdg = wind_from_hdg->getDoubleValue();
 530         double speed = wind_speed_knots->getDoubleValue();
 531         hdg = (speed == 0.0 ? 270.0 : hdg);
 532         //cout << "Heading = " << hdg << '\n';
 533
 534         FGRunway runway;
 535         bool rwyGood = globals->get_runways()->search(ident, int(hdg), &runway);
 536         if(rwyGood) {
 537                 activeRwy = runway.rwy_no;
 538                 rwy.rwyID = runway.rwy_no;
 539                 SG_LOG(SG_ATC, SG_INFO, "Active runway for airport " << ident << " is " << activeRwy);
 540
 541                 // Get the threshold position
 542                 double other_way = runway.heading - 180.0;
 543                 while(other_way <= 0.0) {
 544                         other_way += 360.0;
 545                 }
 546         // move to the +l end/center of the runway
 547                 //cout << "Runway center is at " << runway.lon << ", " << runway.lat << '\n';
 548         Point3D origin = Point3D(runway.lon, runway.lat, aptElev);
 549                 Point3D ref = origin;
 550         double tshlon, tshlat, tshr;
 551                 double tolon, tolat, tor;
 552                 rwy.length = runway.length * SG_FEET_TO_METER;
 553                 rwy.width = runway.width * SG_FEET_TO_METER;
 554         geo_direct_wgs_84 ( aptElev, ref.lat(), ref.lon(), other_way,
 555                                 rwy.length / 2.0 - 25.0, &tshlat, &tshlon, &tshr );
 556         geo_direct_wgs_84 ( aptElev, ref.lat(), ref.lon(), runway.heading,
 557                                 rwy.length / 2.0 - 25.0, &tolat, &tolon, &tor );
 558                 // Note - 25 meters in from the runway end is a bit of a hack to put the plane ahead of the user.
 559                 // now copy what we need out of runway into rwy
 560         rwy.threshold_pos = Point3D(tshlon, tshlat, aptElev);
 561                 Point3D takeoff_end = Point3D(tolon, tolat, aptElev);
 562                 //cout << "Threshold position = " << tshlon << ", " << tshlat << ", " << aptElev << '\n';
 563                 //cout << "Takeoff position = " << tolon << ", " << tolat << ", " << aptElev << '\n';
 564                 rwy.hdg = runway.heading;
 565                 // Set the projection for the local area based on this active runway
 566                 ortho.Init(rwy.threshold_pos, rwy.hdg);
 567                 rwy.end1ortho = ortho.ConvertToLocal(rwy.threshold_pos);        // should come out as zero
 568                 rwy.end2ortho = ortho.ConvertToLocal(takeoff_end);
 569         } else {
 570                 SG_LOG(SG_ATC, SG_ALERT, "Help  - can't get good runway in FGTower!!");
 571                 activeRwy = "NN";
 572         }
 573 }
 574
 575
 576 // Figure out if a given position lies on the active runway
 577 // Might have to change when we consider more than one active rwy.
 578 bool FGTower::OnActiveRunway(Point3D pt) {
 579         // TODO - check that the centre calculation below isn't confused by displaced thesholds etc.
 580         Point3D xyc((rwy.end1ortho.x() + rwy.end2ortho.x())/2.0, (rwy.end1ortho.y() + rwy.end2ortho.y())/2.0, 0.0);
 581         Point3D xyp = ortho.ConvertToLocal(pt);
 582
 583         //cout << "Length offset = " << fabs(xyp.y() - xyc.y()) << '\n';
 584         //cout << "Width offset = " << fabs(xyp.x() - xyc.x()) << '\n';
 585
 586         double rlen = rwy.length/2.0 + 5.0;
 587         double rwidth = rwy.width/2.0;
 588         double ldiff = fabs(xyp.y() - xyc.y());
 589         double wdiff = fabs(xyp.x() - xyc.x());
 590
 591         return((ldiff < rlen) && (wdiff < rwidth));
 592 }
 593
 594
 595 // Figure out if a given position lies on any runway or not
 596 // Only call this at startup - reading the runways database is expensive and needs to be fixed!
 597 bool FGTower::OnAnyRunway(Point3D pt) {
 598         ATCData ad;
 599         double dist = current_commlist->FindClosest(lon, lat, elev, ad, TOWER, 10.0);
 600         if(dist < 0.0) {
 601                 return(false);
 602         }
 603         // Based on the airport-id, go through all the runways and check for a point in them
 604
 605         // TODO - do we actually need to search for the airport - surely we already know our ident and
 606         // can just search runways of our airport???
 607         //cout << "Airport ident is " << ad.ident << '\n';
 608         FGRunway runway;
 609         bool rwyGood = globals->get_runways()->search(ad.ident, &runway);
 610         if(!rwyGood) {
 611                 SG_LOG(SG_ATC, SG_WARN, "Unable to find any runways for airport ID " << ad.ident << " in FGTower");
 612         }
 613         bool on = false;
 614         while(runway.id == ad.ident) {
 615                 on = OnRunway(pt, runway);
 616                 //cout << "Runway " << runway.rwy_no << ": On = " << (on ? "true\n" : "false\n");
 617                 if(on) return(true);
 618                 globals->get_runways()->next(&runway);
 619         }
 620         return(on);
 621 }
 622
 623
 624 // Calculate the eta of each plane to the threshold.
 625 // For ground traffic this is the fastest they can get there.
 626 // For air traffic this is the middle approximation.
 627 void FGTower::doThresholdETACalc() {
 628         // For now we'll be very crude and hardwire expected speeds to C172-like values
 629         // The speeds below are specified in knots IAS and then converted to m/s
 630         double app_ias = 100.0 * 0.514444;                      // Speed during straight-in approach
 631         double circuit_ias = 80.0 * 0.514444;           // Speed around circuit
 632         double final_ias = 70.0 * 0.514444;             // Speed during final approach
 633
 634         tower_plane_rec_list_iterator twrItr;
 635
 636         // Sign convention - dist_out is -ve for approaching planes and +ve for departing planes
 637         // dist_across is +ve in the pattern direction - ie a plane correctly on downwind will have a +ve dist_across
 638         for(twrItr = trafficList.begin(); twrItr != trafficList.end(); twrItr++) {
 639                 TowerPlaneRec* tpr = *twrItr;
 640                 Point3D op = ortho.ConvertToLocal(tpr->pos);
 641                 double dist_out_m = op.y();
 642                 double dist_across_m = fabs(op.x());    // FIXME = the fabs is a hack to cope with the fact that we don't know the circuit direction yet
 643                 //cout << "Doing ETA calc for " << tpr->plane.callsign << '\n';
 644                 if(tpr->opType == CIRCUIT) {
 645                         // It's complicated - depends on if base leg is delayed or not
 646                         if(tpr->leg == LANDING_ROLL) {
 647                                 tpr->eta = 0;
 648                         } else if((tpr->leg == FINAL) || (tpr->leg == TURN4)) {
 649                                 tpr->eta = fabs(dist_out_m) / final_ias;
 650                         } else if((tpr->leg == BASE) || (tpr->leg == TURN3)) {
 651                                 tpr->eta = (fabs(dist_out_m) / final_ias) + (dist_across_m / circuit_ias);
 652                         } else {
 653                                 // Need to calculate where base leg is likely to be
 654                                 // FIXME - for now I'll hardwire it to 1000m which is what AILocalTraffic uses!!!
 655                                 // TODO - as a matter of design - AILocalTraffic should get the nominal no-traffic base turn distance from Tower, since in real life the published pattern might differ from airport to airport
 656                                 double nominal_base_dist_out_m = -1000;
 657                                 double current_base_dist_out_m = nominal_base_dist_out_m;
 658                                 double nominal_dist_across_m = 1000;    // Hardwired value from AILocalTraffic
 659                                 double nominal_cross_dist_out_m = 1000; // Bit of a guess - AI plane turns to crosswind at 600ft agl.
 660                                 tpr->eta = fabs(current_base_dist_out_m) / final_ias;   // final
 661                                 if((tpr->leg == DOWNWIND) || (tpr->leg == TURN2)) {
 662                                         tpr->eta += dist_across_m / circuit_ias;
 663                                         tpr->eta += fabs(current_base_dist_out_m - dist_out_m) / circuit_ias;
 664                                 } else if((tpr->leg == CROSSWIND) || (tpr->leg == TURN1)) {
 665                                         tpr->eta += nominal_dist_across_m / circuit_ias;        // should we use the dist across of the previous plane if there is previous still on downwind?
 666                                         tpr->eta += fabs(current_base_dist_out_m - nominal_cross_dist_out_m) / circuit_ias;
 667                                         tpr->eta += (nominal_dist_across_m - dist_across_m) / circuit_ias;
 668                                 } else {
 669                                         // We've only just started - why not use a generic estimate?
 670                                 }
 671                         }
 672                 } else if((tpr->opType == INBOUND) || (tpr->opType == STRAIGHT_IN)) {
 673                         // It's simpler!
 674                 } else {
 675                         // Must be outbound - ignore it!
 676                 }
 677                 //cout << "ETA = " << tpr->eta << '\n';
 678         }
 679 }
 680
 681
 682 bool FGTower::doThresholdUseOrder() {
 683         return(true);
 684 }
 685
 686 void FGTower::doCommunication() {
 687 }
 688
 689 void FGTower::ContactAtHoldShort(PlaneRec plane, FGAIPlane* requestee, tower_traffic_type operation) {
 690         // HACK - assume that anything contacting at hold short is new for now - FIXME LATER
 691         TowerPlaneRec* t = new TowerPlaneRec;
 692         t->plane = plane;
 693         t->planePtr = requestee;
 694         t->holdShortReported = true;
 695         t->clearanceCounter = 0;
 696         t->clearedToLineUp = false;
 697         t->clearedToTakeOff = false;
 698         t->opType = operation;
 699
 700         // HACK ALERT - THIS IS HARDWIRED FOR TESTING - FIXME TODO ETC
 701         t->nextOnRwy = true;
 702
 703         //cout << "t = " << t << '\n';
 704
 705         holdList.push_back(t);
 706 }
 707
 708 void FGTower::RequestLandingClearance(string ID) {
 709         //cout << "Request Landing Clearance called...\n";
 710 }
 711 void FGTower::RequestDepartureClearance(string ID) {
 712         //cout << "Request Departure Clearance called...\n";
 713 }
 714 //void FGTower::ReportFinal(string ID);
 715 //void FGTower::ReportLongFinal(string ID);
 716 //void FGTower::ReportOuterMarker(string ID);
 717 //void FGTower::ReportMiddleMarker(string ID);
 718 //void FGTower::ReportInnerMarker(string ID);
 719 //void FGTower::ReportGoingAround(string ID);
 720 void FGTower::ReportRunwayVacated(string ID) {
 721         //cout << "Report Runway Vacated Called...\n";
 722 }