src/AIModel/AIAircraft.cxx

   1 // // FGAIAircraft - FGAIBase-derived class creates an AI airplane
   2 //
   3 // Written by David Culp, started October 2003.
   4 //
   5 // Copyright (C) 2003  David P. Culp - davidculp2@comcast.net
   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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20
  21 #ifdef HAVE_CONFIG_H
  22 #  include <config.h>
  23 #endif
  24
  25 #include <simgear/route/waypoint.hxx>
  26 #include <Main/fg_props.hxx>
  27 #include <Main/globals.hxx>
  28 #include <Main/viewer.hxx>
  29 #include <Scenery/scenery.hxx>
  30 #include <Scenery/tilemgr.hxx>
  31 #include <Airports/dynamics.hxx>
  32 #include <Airports/simple.hxx>
  33
  34 #include <string>
  35 #include <math.h>
  36 #include <time.h>
  37
  38 #ifdef _MSC_VER
  39 #  include <float.h>
  40 #  define finite _finite
  41 #elif defined(__sun) || defined(sgi)
  42 #  include <ieeefp.h>
  43 #endif
  44
  45 using std::string;
  46
  47 #include "AIAircraft.hxx"
  48 #include "performancedata.hxx"
  49 #include "performancedb.hxx"
  50
  51 //#include <Airports/trafficcontroller.hxx>
  52
  53 static string tempReg;
  54
  55 FGAIAircraft::FGAIAircraft(FGAISchedule *ref) : FGAIBase(otAircraft) {
  56     trafficRef = ref;
  57     if (trafficRef) {
  58         groundOffset = trafficRef->getGroundOffset();
  59         setCallSign(trafficRef->getCallSign());
  60     }
  61     else
  62         groundOffset = 0;
  63
  64     fp = 0;
  65     controller = 0;
  66     prevController = 0;
  67     dt_count = 0;
  68     dt_elev_count = 0;
  69     use_perf_vs = true;
  70
  71     no_roll = false;
  72     tgt_speed = 0;
  73     speed = 0;
  74     groundTargetSpeed = 0;
  75
  76     // set heading and altitude locks
  77     hdg_lock = false;
  78     alt_lock = false;
  79     roll = 0;
  80     headingChangeRate = 0.0;
  81     headingError = 0;
  82     minBearing = 360;
  83     speedFraction =1.0;
  84
  85     holdPos = false;
  86     needsTaxiClearance = false;
  87     _needsGroundElevation = true;
  88
  89     _performance = 0; //TODO initialize to JET_TRANSPORT from PerformanceDB
  90     dt = 0;
  91 }
  92
  93
  94 FGAIAircraft::~FGAIAircraft() {
  95     //delete fp;
  96     if (controller)
  97         controller->signOff(getID());
  98 }
  99
 100
 101 void FGAIAircraft::readFromScenario(SGPropertyNode* scFileNode) {
 102     if (!scFileNode)
 103         return;
 104
 105     FGAIBase::readFromScenario(scFileNode);
 106
 107     setPerformance(scFileNode->getStringValue("class", "jet_transport"));
 108     setFlightPlan(scFileNode->getStringValue("flightplan"),
 109                   scFileNode->getBoolValue("repeat", false));
 110     setCallSign(scFileNode->getStringValue("callsign"));
 111 }
 112
 113
 114 void FGAIAircraft::bind() {
 115     FGAIBase::bind();
 116
 117     props->tie("controls/gear/gear-down",
 118                SGRawValueMethods<FGAIAircraft,bool>(*this,
 119                                                     &FGAIAircraft::_getGearDown));
 120     props->tie("transponder-id",
 121                SGRawValueMethods<FGAIAircraft,const char*>(*this,
 122                                                     &FGAIAircraft::_getTransponderCode));
 123 }
 124
 125
 126 void FGAIAircraft::unbind() {
 127     FGAIBase::unbind();
 128
 129     props->untie("controls/gear/gear-down");
 130     props->untie("transponder-id");
 131 }
 132
 133
 134 void FGAIAircraft::update(double dt) {
 135     FGAIBase::update(dt);
 136     Run(dt);
 137     Transform();
 138 }
 139
 140 void FGAIAircraft::setPerformance(const std::string& acclass) {
 141      static PerformanceDB perfdb; //TODO make it a global service
 142      setPerformance(perfdb.getDataFor(acclass));
 143   }
 144
 145
 146  void FGAIAircraft::setPerformance(PerformanceData *ps) {
 147      _performance = ps;
 148   }
 149
 150
 151  void FGAIAircraft::Run(double dt) {
 152       FGAIAircraft::dt = dt;
 153
 154      bool outOfSight = false,
 155         flightplanActive = true;
 156      updatePrimaryTargetValues(flightplanActive, outOfSight); // target hdg, alt, speed
 157      if (outOfSight) {
 158         return;
 159      }
 160
 161      if (!flightplanActive) {
 162         groundTargetSpeed = 0;
 163      }
 164
 165      handleATCRequests(); // ATC also has a word to say
 166      updateSecondaryTargetValues(); // target roll, vertical speed, pitch
 167      updateActualState();
 168      UpdateRadar(manager);
 169      checkVisibility();
 170   }
 171
 172 void FGAIAircraft::checkVisibility()
 173 {
 174   double visibility_meters = fgGetDouble("/environment/visibility-m");
 175   FGViewer* vw = globals->get_current_view();
 176   invisible = (SGGeodesy::distanceM(vw->getPosition(), pos) > visibility_meters);
 177 }
 178
 179
 180
 181 void FGAIAircraft::AccelTo(double speed) {
 182     tgt_speed = speed;
 183     if (!isStationary())
 184         _needsGroundElevation = true;
 185 }
 186
 187
 188 void FGAIAircraft::PitchTo(double angle) {
 189     tgt_pitch = angle;
 190     alt_lock = false;
 191 }
 192
 193
 194 void FGAIAircraft::RollTo(double angle) {
 195     tgt_roll = angle;
 196     hdg_lock = false;
 197 }
 198
 199
 200 void FGAIAircraft::YawTo(double angle) {
 201     tgt_yaw = angle;
 202 }
 203
 204
 205 void FGAIAircraft::ClimbTo(double alt_ft ) {
 206     tgt_altitude_ft = alt_ft;
 207     alt_lock = true;
 208 }
 209
 210
 211 void FGAIAircraft::TurnTo(double heading) {
 212     tgt_heading = heading;
 213     hdg_lock = true;
 214 }
 215
 216
 217 double FGAIAircraft::sign(double x) {
 218     if (x == 0.0)
 219         return x;
 220     else
 221         return x/fabs(x);
 222 }
 223
 224
 225 void FGAIAircraft::setFlightPlan(const std::string& flightplan, bool repeat) {
 226     if (!flightplan.empty()) {
 227         FGAIFlightPlan* fp = new FGAIFlightPlan(flightplan);
 228         fp->setRepeat(repeat);
 229         SetFlightPlan(fp);
 230     }
 231 }
 232
 233
 234 void FGAIAircraft::SetFlightPlan(FGAIFlightPlan *f) {
 235     delete fp;
 236     fp = f;
 237 }
 238
 239
 240 void FGAIAircraft::ProcessFlightPlan( double dt, time_t now ) {
 241
 242     // the one behind you
 243     FGAIFlightPlan::waypoint* prev = 0;
 244     // the one ahead
 245     FGAIFlightPlan::waypoint* curr = 0;
 246     // the next plus 1
 247     FGAIFlightPlan::waypoint* next = 0;
 248
 249     prev = fp->getPreviousWaypoint();
 250     curr = fp->getCurrentWaypoint();
 251     next = fp->getNextWaypoint();
 252
 253     dt_count += dt;
 254
 255     ///////////////////////////////////////////////////////////////////////////
 256     // Initialize the flightplan
 257     //////////////////////////////////////////////////////////////////////////
 258     if (!prev) {
 259         handleFirstWaypoint();
 260         return;
 261     }                            // end of initialization
 262     if (! fpExecutable(now))
 263           return;
 264     dt_count = 0;
 265
 266     double distanceToDescent;
 267     if(reachedEndOfCruise(distanceToDescent)) {
 268         if (!loadNextLeg(distanceToDescent)) {
 269             setDie(true);
 270             return;
 271         }
 272         prev = fp->getPreviousWaypoint();
 273         curr = fp->getCurrentWaypoint();
 274         next = fp->getNextWaypoint();
 275     }
 276     if (! leadPointReached(curr)) {
 277         controlHeading(curr);
 278         controlSpeed(curr, next);
 279             if (speed < 0) {
 280                 cerr << getCallSign()
 281                      << ": verifying lead distance to waypoint : "
 282                      << fp->getCurrentWaypoint()->name << " "
 283                      << fp->getLeadDistance() << ". Distance to go "
 284                      << (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr))
 285                      << ". Target speed = "
 286                      << tgt_speed
 287                      << ". Current speed = "
 288                      << speed
 289                      << ". Minimum Bearing " << minBearing
 290                      << endl;
 291             }
 292     } else {
 293         if (curr->finished)      //end of the flight plan
 294         {
 295             if (fp->getRepeat())
 296                 fp->restart();
 297             else
 298                 setDie(true);
 299             return;
 300         }
 301
 302         if (next) {
 303             //TODO more intelligent method in AIFlightPlan, no need to send data it already has :-)
 304             tgt_heading = fp->getBearing(curr, next);
 305             spinCounter = 0;
 306         }
 307
 308         //TODO let the fp handle this (loading of next leg)
 309         fp->IncrementWaypoint( trafficRef != 0 );
 310         if  ( ((!(fp->getNextWaypoint()))) && (trafficRef != 0) )
 311             if (!loadNextLeg()) {
 312                 setDie(true);
 313                 return;
 314             }
 315
 316         prev = fp->getPreviousWaypoint();
 317         curr = fp->getCurrentWaypoint();
 318         next = fp->getNextWaypoint();
 319
 320         // Now that we have incremented the waypoints, excute some traffic manager specific code
 321         if (trafficRef) {
 322             //TODO isn't this best executed right at the beginning?
 323             if (! aiTrafficVisible()) {
 324                 setDie(true);
 325                 return;
 326             }
 327
 328             if (! handleAirportEndPoints(prev, now)) {
 329                 setDie(true);
 330                 return;
 331             }
 332
 333             announcePositionToController();
 334
 335         }
 336
 337         if (next) {
 338             fp->setLeadDistance(tgt_speed, tgt_heading, curr, next);
 339         }
 340
 341         if (!(prev->on_ground))  // only update the tgt altitude from flightplan if not on the ground
 342         {
 343             tgt_altitude_ft = prev->altitude;
 344             if (curr->crossat > -1000.0) {
 345                 use_perf_vs = false;
 346                 tgt_vs = (curr->crossat - altitude_ft) / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 347                          / 6076.0 / speed*60.0);
 348                 checkTcas();
 349                 tgt_altitude_ft = curr->crossat;
 350             } else {
 351                 use_perf_vs = true;
 352             }
 353         }
 354         AccelTo(prev->speed);
 355         hdg_lock = alt_lock = true;
 356         no_roll = prev->on_ground;
 357     }
 358 }
 359
 360 void FGAIAircraft::checkTcas(void)
 361 {
 362     if (props->getIntValue("tcas/threat-level",0)==3)
 363     {
 364         int RASense = props->getIntValue("tcas/ra-sense",0);
 365         if ((RASense>0)&&(tgt_vs<4000))
 366             // upward RA: climb!
 367             tgt_vs = 4000;
 368         else
 369         if (RASense<0)
 370         {
 371             // downward RA: descend!
 372             if (altitude_ft < 1000)
 373             {
 374                 // too low: level off
 375                 if (tgt_vs>0)
 376                     tgt_vs = 0;
 377             }
 378             else
 379             {
 380                 if (tgt_vs >- 4000)
 381                     tgt_vs = -4000;
 382             }
 383         }
 384     }
 385 }
 386
 387 void FGAIAircraft::initializeFlightPlan() {
 388 }
 389
 390
 391 bool FGAIAircraft::_getGearDown() const {
 392     return _performance->gearExtensible(this);
 393 }
 394
 395
 396 const char * FGAIAircraft::_getTransponderCode() const {
 397   return transponderCode.c_str();
 398 }
 399
 400
 401 bool FGAIAircraft::loadNextLeg(double distance) {
 402
 403     int leg;
 404     if ((leg = fp->getLeg())  == 10) {
 405         if (!trafficRef->next()) {
 406             return false;
 407         }
 408         setCallSign(trafficRef->getCallSign());
 409         leg = 1;
 410         fp->setLeg(leg);
 411     }
 412
 413     FGAirport *dep = trafficRef->getDepartureAirport();
 414     FGAirport *arr = trafficRef->getArrivalAirport();
 415     if (!(dep && arr)) {
 416         setDie(true);
 417
 418     } else {
 419         double cruiseAlt = trafficRef->getCruiseAlt() * 100;
 420
 421         fp->create (this,
 422                     dep,
 423                     arr,
 424                     leg,
 425                     cruiseAlt,
 426                     trafficRef->getSpeed(),
 427                     _getLatitude(),
 428                     _getLongitude(),
 429                     false,
 430                     trafficRef->getRadius(),
 431                     trafficRef->getFlightType(),
 432                     acType,
 433                     company,
 434                     distance);
 435        //cerr << "created  leg " << leg << " for " << trafficRef->getCallSign() << endl;
 436     }
 437     return true;
 438 }
 439
 440
 441 // Note: This code is copied from David Luff's AILocalTraffic
 442 // Warning - ground elev determination is CPU intensive
 443 // Either this function or the logic of how often it is called
 444 // will almost certainly change.
 445
 446 void FGAIAircraft::getGroundElev(double dt) {
 447     dt_elev_count += dt;
 448
 449     if (!needGroundElevation())
 450         return;
 451     // Update minimally every three secs, but add some randomness
 452     // to prevent all AI objects doing this in synchrony
 453     if (dt_elev_count < (3.0) + (rand() % 10))
 454         return;
 455
 456     dt_elev_count = 0;
 457
 458     // Only do the proper hitlist stuff if we are within visible range of the viewer.
 459     if (!invisible) {
 460         double visibility_meters = fgGetDouble("/environment/visibility-m");
 461         FGViewer* vw = globals->get_current_view();
 462
 463         if (SGGeodesy::distanceM(vw->getPosition(), pos) > visibility_meters) {
 464             return;
 465         }
 466
 467         double range = 500.0;
 468         if (globals->get_tile_mgr()->schedule_scenery(pos, range, 5.0))
 469         {
 470             double alt;
 471             if (getGroundElevationM(SGGeod::fromGeodM(pos, 20000), alt, 0))
 472             {
 473                 tgt_altitude_ft = alt * SG_METER_TO_FEET;
 474                 if (isStationary())
 475                 {
 476                     // aircraft is stationary and we obtained altitude for this spot - we're done.
 477                     _needsGroundElevation = false;
 478                 }
 479             }
 480         }
 481     }
 482 }
 483
 484
 485 void FGAIAircraft::doGroundAltitude() {
 486     if ((fabs(altitude_ft - (tgt_altitude_ft+groundOffset)) > 1000.0)||
 487         (isStationary()))
 488         altitude_ft = (tgt_altitude_ft + groundOffset);
 489     else
 490         altitude_ft += 0.1 * ((tgt_altitude_ft+groundOffset) - altitude_ft);
 491     tgt_vs = 0;
 492 }
 493
 494
 495 void FGAIAircraft::announcePositionToController() {
 496     if (trafficRef) {
 497         int leg = fp->getLeg();
 498
 499         // Note that leg has been incremented after creating the current leg, so we should use
 500         // leg numbers here that are one higher than the number that is used to create the leg
 501         //
 502         switch (leg) {
 503           case 2:              // Startup and Push back
 504             if (trafficRef->getDepartureAirport()->getDynamics())
 505                 controller = trafficRef->getDepartureAirport()->getDynamics()->getStartupController();
 506             break;
 507         case 3:              // Taxiing to runway
 508             if (trafficRef->getDepartureAirport()->getDynamics()->getGroundNetwork()->exists())
 509                 controller = trafficRef->getDepartureAirport()->getDynamics()->getGroundNetwork();
 510             break;
 511         case 4:              //Take off tower controller
 512             if (trafficRef->getDepartureAirport()->getDynamics()) {
 513                 controller = trafficRef->getDepartureAirport()->getDynamics()->getTowerController();
 514             } else {
 515                 cerr << "Error: Could not find Dynamics at airport : " << trafficRef->getDepartureAirport()->getId() << endl;
 516             }
 517             break;
 518         case 7:
 519              if (trafficRef->getDepartureAirport()->getDynamics()) {
 520                  controller = trafficRef->getArrivalAirport()->getDynamics()->getApproachController();
 521               }
 522               break;
 523         case 9:              // Taxiing for parking
 524             if (trafficRef->getArrivalAirport()->getDynamics()->getGroundNetwork()->exists())
 525                 controller = trafficRef->getArrivalAirport()->getDynamics()->getGroundNetwork();
 526             break;
 527         default:
 528             controller = 0;
 529             break;
 530         }
 531
 532         if ((controller != prevController) && (prevController != 0)) {
 533             prevController->signOff(getID());
 534         }
 535         prevController = controller;
 536         if (controller) {
 537             controller->announcePosition(getID(), fp, fp->getCurrentWaypoint()->routeIndex,
 538                                          _getLatitude(), _getLongitude(), hdg, speed, altitude_ft,
 539                                          trafficRef->getRadius(), leg, this);
 540         }
 541     }
 542 }
 543
 544 // Process ATC instructions and report back
 545
 546 void FGAIAircraft::processATC(FGATCInstruction instruction) {
 547     if (instruction.getCheckForCircularWait()) {
 548         // This is not exactly an elegant solution,
 549         // but at least it gives me a chance to check
 550         // if circular waits are resolved.
 551         // For now, just take the offending aircraft
 552         // out of the scene
 553         setDie(true);
 554         // a more proper way should be - of course - to
 555         // let an offending aircraft take an evasive action
 556         // for instance taxi back a little bit.
 557     }
 558     //cerr << "Processing ATC instruction (not Implimented yet)" << endl;
 559     if (instruction.getHoldPattern   ()) {}
 560
 561     // Hold Position
 562     if (instruction.getHoldPosition  ()) {
 563         if (!holdPos) {
 564             holdPos = true;
 565         }
 566         AccelTo(0.0);
 567     } else {
 568         if (holdPos) {
 569             //if (trafficRef)
 570             //  cerr << trafficRef->getCallSign() << " Resuming Taxi." << endl;
 571             holdPos = false;
 572         }
 573         // Change speed Instruction. This can only be excecuted when there is no
 574         // Hold position instruction.
 575         if (instruction.getChangeSpeed   ()) {
 576             //  if (trafficRef)
 577             //cerr << trafficRef->getCallSign() << " Changing Speed " << endl;
 578             AccelTo(instruction.getSpeed());
 579         } else {
 580             if (fp) AccelTo(fp->getPreviousWaypoint()->speed);
 581         }
 582     }
 583     if (instruction.getChangeHeading ()) {
 584         hdg_lock = false;
 585         TurnTo(instruction.getHeading());
 586     } else {
 587         if (fp) {
 588             hdg_lock = true;
 589         }
 590     }
 591     if (instruction.getChangeAltitude()) {}
 592
 593 }
 594
 595
 596 void FGAIAircraft::handleFirstWaypoint() {
 597     bool eraseWaypoints;         //TODO YAGNI
 598     headingError = 0;
 599     if (trafficRef) {
 600         eraseWaypoints = true;
 601     } else {
 602         eraseWaypoints = false;
 603     }
 604
 605     FGAIFlightPlan::waypoint* prev = 0; // the one behind you
 606     FGAIFlightPlan::waypoint* curr = 0; // the one ahead
 607     FGAIFlightPlan::waypoint* next = 0;// the next plus 1
 608
 609     spinCounter = 0;
 610     tempReg = "";
 611
 612     //TODO fp should handle this
 613     fp->IncrementWaypoint(eraseWaypoints);
 614     if (!(fp->getNextWaypoint()) && trafficRef)
 615         if (!loadNextLeg()) {
 616             setDie(true);
 617             return;
 618         }
 619
 620     prev = fp->getPreviousWaypoint();   //first waypoint
 621     curr = fp->getCurrentWaypoint();    //second waypoint
 622     next = fp->getNextWaypoint();       //third waypoint (might not exist!)
 623
 624     setLatitude(prev->latitude);
 625     setLongitude(prev->longitude);
 626     setSpeed(prev->speed);
 627     setAltitude(prev->altitude);
 628
 629     if (prev->speed > 0.0)
 630         setHeading(fp->getBearing(prev->latitude, prev->longitude, curr));
 631     else
 632         setHeading(fp->getBearing(curr->latitude, curr->longitude, prev));
 633
 634     // If next doesn't exist, as in incrementally created flightplans for
 635     // AI/Trafficmanager created plans,
 636     // Make sure lead distance is initialized otherwise
 637     if (next)
 638         fp->setLeadDistance(speed, hdg, curr, next);
 639
 640     if (curr->crossat > -1000.0) //use a calculated descent/climb rate
 641     {
 642         use_perf_vs = false;
 643         tgt_vs = (curr->crossat - prev->altitude)
 644                  / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 645                     / 6076.0 / prev->speed*60.0);
 646         checkTcas();
 647         tgt_altitude_ft = curr->crossat;
 648     } else {
 649         use_perf_vs = true;
 650         tgt_altitude_ft = prev->altitude;
 651     }
 652     alt_lock = hdg_lock = true;
 653     no_roll = prev->on_ground;
 654     if (no_roll) {
 655         Transform();             // make sure aip is initialized.
 656         getGroundElev(60.1);     // make sure it's executed first time around, so force a large dt value
 657         doGroundAltitude();
 658         _needsGroundElevation = true; // check ground elevation again (maybe scenery wasn't available yet)
 659     }
 660     // Make sure to announce the aircraft's position
 661     announcePositionToController();
 662     prevSpeed = 0;
 663 }
 664
 665
 666 /**
 667  * Check Execution time (currently once every 100 ms)
 668  * Add a bit of randomization to prevent the execution of all flight plans
 669  * in synchrony, which can add significant periodic framerate flutter.
 670  *
 671  * @param now
 672  * @return
 673  */
 674 bool FGAIAircraft::fpExecutable(time_t now) {
 675     double rand_exec_time = (rand() % 100) / 100;
 676     return (dt_count > (0.1+rand_exec_time)) && (fp->isActive(now));
 677 }
 678
 679
 680 /**
 681  * Check to see if we've reached the lead point for our next turn
 682  *
 683  * @param curr
 684  * @return
 685  */
 686 bool FGAIAircraft::leadPointReached(FGAIFlightPlan::waypoint* curr) {
 687     double dist_to_go = fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 688
 689     //cerr << "2" << endl;
 690     double lead_dist = fp->getLeadDistance();
 691     // experimental: Use fabs, because speed can be negative (I hope) during push_back.
 692     if ((dist_to_go < fabs(10.0* speed)) && (speed < 0) && (tgt_speed < 0) && fp->getCurrentWaypoint()->name == string("PushBackPoint")) {
 693           tgt_speed = -(dist_to_go / 10.0);
 694           if (tgt_speed > -0.5) {
 695                 tgt_speed = -0.5;
 696           }
 697           if (fp->getPreviousWaypoint()->speed < tgt_speed) {
 698               fp->getPreviousWaypoint()->speed = tgt_speed;
 699           }
 700     }
 701     if (lead_dist < fabs(2*speed)) {
 702       //don't skip over the waypoint
 703       lead_dist = fabs(2*speed);
 704       //cerr << "Extending lead distance to " << lead_dist << endl;
 705     }
 706
 707     //prev_dist_to_go = dist_to_go;
 708     //if (dist_to_go < lead_dist)
 709     //     cerr << trafficRef->getCallSign() << " Distance : "
 710     //          << dist_to_go << ": Lead distance "
 711     //          << lead_dist << " " << curr->name
 712     //          << " Ground target speed " << groundTargetSpeed << endl;
 713     double bearing = 0;
 714     if (speed > 50) { // don't do bearing calculations for ground traffic
 715        bearing = getBearing(fp->getBearing(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr));
 716        if (bearing < minBearing) {
 717             minBearing = bearing;
 718             if (minBearing < 10) {
 719                  minBearing = 10;
 720             }
 721             if ((minBearing < 360.0) && (minBearing > 10.0)) {
 722                 speedFraction = cos(minBearing *SG_DEGREES_TO_RADIANS);
 723             } else {
 724                 speedFraction = 1.0;
 725             }
 726        }
 727     }
 728     if (trafficRef) {
 729          //cerr << "Tracking callsign : \"" << fgGetString("/ai/track-callsign") << "\"" << endl;
 730 /*         if (trafficRef->getCallSign() == fgGetString("/ai/track-callsign")) {
 731               cerr << trafficRef->getCallSign() << " " << tgt_altitude_ft << " " << _getSpeed() << " "
 732                    << _getAltitude() << " "<< _getLatitude() << " " << _getLongitude() << " " << dist_to_go << " " << lead_dist << " " << curr->name << " " << vs << " " << tgt_vs << " " << bearing << " " << minBearing << " " << speedFraction << endl;
 733          }*/
 734      }
 735     if ((dist_to_go < lead_dist) || (bearing > (minBearing * 1.1))) {
 736         minBearing = 360;
 737         return true;
 738     } else {
 739         return false;
 740     }
 741 }
 742
 743
 744 bool FGAIAircraft::aiTrafficVisible() {
 745   SGGeod userPos(SGGeod::fromDeg(fgGetDouble("/position/longitude-deg"),
 746     fgGetDouble("/position/latitude-deg")));
 747
 748   return (SGGeodesy::distanceNm(userPos, pos) <= TRAFFICTOAIDISTTODIE);
 749 }
 750
 751
 752 /**
 753  * Handle release of parking gate, once were taxiing. Also ensure service time at the gate
 754  * in the case of an arrival.
 755  *
 756  * @param prev
 757  * @return
 758  */
 759
 760 //TODO the trafficRef is the right place for the method
 761 bool FGAIAircraft::handleAirportEndPoints(FGAIFlightPlan::waypoint* prev, time_t now) {
 762     // prepare routing from one airport to another
 763     FGAirport * dep = trafficRef->getDepartureAirport();
 764     FGAirport * arr = trafficRef->getArrivalAirport();
 765
 766     if (!( dep && arr))
 767         return false;
 768
 769     // This waypoint marks the fact that the aircraft has passed the initial taxi
 770     // departure waypoint, so it can release the parking.
 771     //cerr << trafficRef->getCallSign() << " has passed waypoint " << prev->name << " at speed " << speed << endl;
 772     if (prev->name == "PushBackPoint") {
 773         dep->getDynamics()->releaseParking(fp->getGate());
 774         AccelTo(0.0);
 775         setTaxiClearanceRequest(true);
 776     }
 777
 778     // This is the last taxi waypoint, and marks the the end of the flight plan
 779     // so, the schedule should update and wait for the next departure time.
 780     if (prev->name == "END") {
 781         time_t nextDeparture = trafficRef->getDepartureTime();
 782         // make sure to wait at least 20 minutes at parking to prevent "nervous" taxi behavior
 783         if (nextDeparture < (now+1200)) {
 784             nextDeparture = now + 1200;
 785         }
 786         fp->setTime(nextDeparture); // should be "next departure"
 787     }
 788
 789     return true;
 790 }
 791
 792
 793 /**
 794  * Check difference between target bearing and current heading and correct if necessary.
 795  *
 796  * @param curr
 797  */
 798 void FGAIAircraft::controlHeading(FGAIFlightPlan::waypoint* curr) {
 799     double calc_bearing = fp->getBearing(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 800     //cerr << "Bearing = " << calc_bearing << endl;
 801     if (speed < 0) {
 802         calc_bearing +=180;
 803         if (calc_bearing > 360)
 804             calc_bearing -= 360;
 805     }
 806
 807     if (finite(calc_bearing)) {
 808         double hdg_error = calc_bearing - tgt_heading;
 809         if (fabs(hdg_error) > 0.01) {
 810             TurnTo( calc_bearing );
 811         }
 812
 813     } else {
 814         cerr << "calc_bearing is not a finite number : "
 815         << "Speed " << speed
 816         << "pos : " << pos.getLatitudeDeg() << ", " << pos.getLongitudeDeg()
 817         << "waypoint " << curr->latitude << ", " << curr->longitude << endl;
 818         cerr << "waypoint name " << curr->name;
 819         exit(1);                 // FIXME
 820     }
 821 }
 822
 823
 824 /**
 825  * Update the lead distance calculation if speed has changed sufficiently
 826  * to prevent spinning (hopefully);
 827  *
 828  * @param curr
 829  * @param next
 830  */
 831 void FGAIAircraft::controlSpeed(FGAIFlightPlan::waypoint* curr, FGAIFlightPlan::waypoint* next) {
 832     double speed_diff = speed - prevSpeed;
 833
 834     if (fabs(speed_diff) > 10) {
 835         prevSpeed = speed;
 836         if (next) {
 837             fp->setLeadDistance(speed, tgt_heading, curr, next);
 838         }
 839     }
 840 }
 841
 842
 843 /**
 844  * Update target values (heading, alt, speed) depending on flight plan or control properties
 845  */
 846 void FGAIAircraft::updatePrimaryTargetValues(bool& flightplanActive, bool& aiOutOfSight) {
 847     if (fp)                      // AI object has a flightplan
 848     {
 849         //TODO make this a function of AIBase
 850         time_t now = time(NULL) + fgGetLong("/sim/time/warp");
 851         //cerr << "UpateTArgetValues() " << endl;
 852         ProcessFlightPlan(dt, now);
 853
 854         // Do execute Ground elev for inactive aircraft, so they
 855         // Are repositioned to the correct ground altitude when the user flies within visibility range.
 856         // In addition, check whether we are out of user range, so this aircraft
 857         // can be deleted.
 858         if (onGround()) {
 859                 Transform();     // make sure aip is initialized.
 860                 getGroundElev(dt);
 861                 doGroundAltitude();
 862                 // Transform();
 863                 pos.setElevationFt(altitude_ft);
 864         }
 865         if (trafficRef) {
 866            //cerr << trafficRef->getRegistration() << " Setting altitude to " << altitude_ft;
 867             aiOutOfSight = !aiTrafficVisible();
 868             if (aiOutOfSight) {
 869                 setDie(true);
 870                 //cerr << trafficRef->getRegistration() << " is set to die " << endl;
 871                 aiOutOfSight = true;
 872                 return;
 873             }
 874         }
 875         timeElapsed = now - fp->getStartTime();
 876         flightplanActive = fp->isActive(now);
 877     } else {
 878         // no flight plan, update target heading, speed, and altitude
 879         // from control properties.  These default to the initial
 880         // settings in the config file, but can be changed "on the
 881         // fly".
 882         string lat_mode = props->getStringValue("controls/flight/lateral-mode");
 883         if ( lat_mode == "roll" ) {
 884             double angle
 885             = props->getDoubleValue("controls/flight/target-roll" );
 886             RollTo( angle );
 887         } else {
 888             double angle
 889             = props->getDoubleValue("controls/flight/target-hdg" );
 890             TurnTo( angle );
 891         }
 892
 893         string lon_mode
 894         = props->getStringValue("controls/flight/longitude-mode");
 895         if ( lon_mode == "alt" ) {
 896             double alt = props->getDoubleValue("controls/flight/target-alt" );
 897             ClimbTo( alt );
 898         } else {
 899             double angle
 900             = props->getDoubleValue("controls/flight/target-pitch" );
 901             PitchTo( angle );
 902         }
 903
 904         AccelTo( props->getDoubleValue("controls/flight/target-spd" ) );
 905     }
 906 }
 907
 908 void FGAIAircraft::updatePosition() {
 909     // convert speed to degrees per second
 910     double speed_north_deg_sec = cos( hdg * SGD_DEGREES_TO_RADIANS )
 911                                  * speed * 1.686 / ft_per_deg_lat;
 912     double speed_east_deg_sec  = sin( hdg * SGD_DEGREES_TO_RADIANS )
 913                                  * speed * 1.686 / ft_per_deg_lon;
 914
 915     // set new position
 916     pos.setLatitudeDeg( pos.getLatitudeDeg() + speed_north_deg_sec * dt);
 917     pos.setLongitudeDeg( pos.getLongitudeDeg() + speed_east_deg_sec * dt);
 918 }
 919
 920
 921 void FGAIAircraft::updateHeading() {
 922     // adjust heading based on current bank angle
 923     if (roll == 0.0)
 924         roll = 0.01;
 925
 926     if (roll != 0.0) {
 927         // double turnConstant;
 928         //if (no_roll)
 929         //  turnConstant = 0.0088362;
 930         //else
 931         //  turnConstant = 0.088362;
 932         // If on ground, calculate heading change directly
 933         if (onGround()) {
 934             double headingDiff = fabs(hdg-tgt_heading);
 935             double bank_sense = 0.0;
 936         /*
 937         double diff = fabs(hdg - tgt_heading);
 938         if (diff > 180)
 939             diff = fabs(diff - 360);
 940
 941         double sum = hdg + diff;
 942         if (sum > 360.0)
 943             sum -= 360.0;
 944         if (fabs(sum - tgt_heading) < 1.0) {
 945             bank_sense = 1.0;    // right turn
 946         } else {
 947             bank_sense = -1.0;   // left turn
 948         }*/
 949             if (headingDiff > 180)
 950                 headingDiff = fabs(headingDiff - 360);
 951             double sum = hdg + headingDiff;
 952             if (sum > 360.0)
 953                 sum -= 360.0;
 954             if (fabs(sum - tgt_heading) > 0.0001) {
 955                 bank_sense = -1.0;
 956             } else {
 957                 bank_sense = 1.0;
 958             }
 959             //if (trafficRef)
 960             //  cerr << trafficRef->getCallSign() << " Heading "
 961             //         << hdg << ". Target " << tgt_heading <<  ". Diff " << fabs(sum - tgt_heading) << ". Speed " << speed << endl;
 962             //if (headingDiff > 60) {
 963             groundTargetSpeed = tgt_speed; // * cos(headingDiff * SG_DEGREES_TO_RADIANS);
 964                 //groundTargetSpeed = tgt_speed - tgt_speed * (headingDiff/180);
 965             //} else {
 966             //    groundTargetSpeed = tgt_speed;
 967             //}
 968             if (sign(groundTargetSpeed) != sign(tgt_speed))
 969                 groundTargetSpeed = 0.21 * sign(tgt_speed); // to prevent speed getting stuck in 'negative' mode
 970
 971             // Only update the target values when we're not moving because otherwise we might introduce an enormous target change rate while waiting a the gate, or holding.
 972             if (speed != 0) {
 973                 if (headingDiff > 30.0) {
 974                     // invert if pushed backward
 975                     headingChangeRate += 10.0 * dt * sign(roll);
 976
 977                     // Clamp the maximum steering rate to 30 degrees per second,
 978                     // But only do this when the heading error is decreasing.
 979                     if ((headingDiff < headingError)) {
 980                         if (headingChangeRate > 30)
 981                             headingChangeRate = 30;
 982                         else if (headingChangeRate < -30)
 983                             headingChangeRate = -30;
 984                     }
 985                 } else {
 986                     if (speed != 0) {
 987                         if (fabs(headingChangeRate) > headingDiff)
 988                             headingChangeRate = headingDiff*sign(roll);
 989                         else
 990                             headingChangeRate += dt * sign(roll);
 991                     }
 992                 }
 993             }
 994             if (trafficRef)
 995                 cerr << trafficRef->getCallSign() << " Heading "
 996                      << hdg << ". Target " << tgt_heading <<  ". Diff " << fabs(sum - tgt_heading) << ". Speed " << speed << "Heading change rate : " << headingChangeRate << " bacnk sence " << bank_sense << endl;
 997             hdg += headingChangeRate * dt * sqrt(fabs(speed) / 15);
 998             headingError = headingDiff;
 999         } else {
1000             if (fabs(speed) > 1.0) {
1001                 turn_radius_ft = 0.088362 * speed * speed
1002                                  / tan( fabs(roll) / SG_RADIANS_TO_DEGREES );
1003             } else {
1004                 // Check if turn_radius_ft == 0; this might lead to a division by 0.
1005                 turn_radius_ft = 1.0;
1006             }
1007             double turn_circum_ft = SGD_2PI * turn_radius_ft;
1008             double dist_covered_ft = speed * 1.686 * dt;
1009             double alpha = dist_covered_ft / turn_circum_ft * 360.0;
1010             hdg += alpha * sign(roll);
1011         }
1012         while ( hdg > 360.0 ) {
1013             hdg -= 360.0;
1014             spinCounter++;
1015         }
1016         while ( hdg < 0.0) {
1017             hdg += 360.0;
1018             spinCounter--;
1019         }
1020     }
1021 }
1022
1023
1024 void FGAIAircraft::updateBankAngleTarget() {
1025     // adjust target bank angle if heading lock engaged
1026     if (hdg_lock) {
1027         double bank_sense = 0.0;
1028         double diff = fabs(hdg - tgt_heading);
1029         if (diff > 180)
1030             diff = fabs(diff - 360);
1031
1032         double sum = hdg + diff;
1033         if (sum > 360.0)
1034             sum -= 360.0;
1035         if (fabs(sum - tgt_heading) < 1.0) {
1036             bank_sense = 1.0;    // right turn
1037         } else {
1038             bank_sense = -1.0;   // left turn
1039         }
1040         if (diff < _performance->maximumBankAngle()) {
1041             tgt_roll = diff * bank_sense;
1042         } else {
1043             tgt_roll = _performance->maximumBankAngle() * bank_sense;
1044         }
1045         if ((fabs((double) spinCounter) > 1) && (diff > _performance->maximumBankAngle())) {
1046             tgt_speed *= 0.999;  // Ugly hack: If aircraft get stuck, they will continually spin around.
1047             // The only way to resolve this is to make them slow down.
1048         }
1049     }
1050 }
1051
1052
1053 void FGAIAircraft::updateVerticalSpeedTarget() {
1054     // adjust target Altitude, based on ground elevation when on ground
1055     if (onGround()) {
1056         getGroundElev(dt);
1057         doGroundAltitude();
1058     } else if (alt_lock) {
1059         // find target vertical speed
1060         if (use_perf_vs) {
1061             if (altitude_ft < tgt_altitude_ft) {
1062                 tgt_vs = tgt_altitude_ft - altitude_ft;
1063                 if (tgt_vs > _performance->climbRate())
1064                     tgt_vs = _performance->climbRate();
1065             } else {
1066                 tgt_vs = tgt_altitude_ft - altitude_ft;
1067                 if (tgt_vs  < (-_performance->descentRate()))
1068                     tgt_vs = -_performance->descentRate();
1069             }
1070         } else {
1071             double max_vs = 4*(tgt_altitude_ft - altitude_ft);
1072             double min_vs = 100;
1073             if (tgt_altitude_ft < altitude_ft)
1074                 min_vs = -100.0;
1075             if ((fabs(tgt_altitude_ft - altitude_ft) < 1500.0)
1076                     && (fabs(max_vs) < fabs(tgt_vs)))
1077                 tgt_vs = max_vs;
1078
1079             if (fabs(tgt_vs) < fabs(min_vs))
1080                 tgt_vs = min_vs;
1081         }
1082     } //else
1083     //    tgt_vs = 0.0;
1084     checkTcas();
1085 }
1086
1087 void FGAIAircraft::updatePitchAngleTarget() {
1088     // if on ground and above vRotate -> initial rotation
1089     if (onGround() && (speed > _performance->vRotate()))
1090         tgt_pitch = 8.0; // some rough B737 value
1091
1092     //TODO pitch angle on approach and landing
1093
1094     // match pitch angle to vertical speed
1095     else if (tgt_vs > 0) {
1096         tgt_pitch = tgt_vs * 0.005;
1097     } else {
1098         tgt_pitch = tgt_vs * 0.002;
1099     }
1100 }
1101
1102 string FGAIAircraft::atGate() {
1103      string tmp("");
1104      if (fp->getLeg() < 3) {
1105          if (trafficRef) {
1106              if (fp->getGate() > 0) {
1107                  FGParking *park =
1108                      trafficRef->getDepartureAirport()->getDynamics()->getParking(fp->getGate());
1109                  tmp = park->getName();
1110              }
1111          }
1112      }
1113      return tmp;
1114 }
1115
1116 void FGAIAircraft::handleATCRequests() {
1117     //TODO implement NullController for having no ATC to save the conditionals
1118     if (controller) {
1119         controller->updateAircraftInformation(getID(),
1120                                               pos.getLatitudeDeg(),
1121                                               pos.getLongitudeDeg(),
1122                                               hdg,
1123                                               speed,
1124                                               altitude_ft, dt);
1125         processATC(controller->getInstruction(getID()));
1126     }
1127 }
1128
1129 void FGAIAircraft::updateActualState() {
1130     //update current state
1131     //TODO have a single tgt_speed and check speed limit on ground on setting tgt_speed
1132     updatePosition();
1133
1134     if (onGround())
1135         speed = _performance->actualSpeed(this, groundTargetSpeed, dt);
1136     else
1137         speed = _performance->actualSpeed(this, (tgt_speed *speedFraction), dt);
1138
1139     updateHeading();
1140     roll = _performance->actualBankAngle(this, tgt_roll, dt);
1141
1142     // adjust altitude (meters) based on current vertical speed (fpm)
1143     altitude_ft += vs / 60.0 * dt;
1144     pos.setElevationFt(altitude_ft);
1145
1146     vs = _performance->actualVerticalSpeed(this, tgt_vs, dt);
1147     pitch = _performance->actualPitch(this, tgt_pitch, dt);
1148 }
1149
1150 void FGAIAircraft::updateSecondaryTargetValues() {
1151     // derived target state values
1152     updateBankAngleTarget();
1153     updateVerticalSpeedTarget();
1154     updatePitchAngleTarget();
1155
1156     //TODO calculate wind correction angle (tgt_yaw)
1157 }
1158
1159
1160 bool FGAIAircraft::reachedEndOfCruise(double &distance) {
1161     FGAIFlightPlan::waypoint* curr = fp->getCurrentWaypoint();
1162     if (curr->name == "BOD") {
1163         double dist = fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
1164         double descentSpeed = (getPerformance()->vDescent() * SG_NM_TO_METER) / 3600.0;     // convert from kts to meter/s
1165         double descentRate  = (getPerformance()->descentRate() * SG_FEET_TO_METER) / 60.0;  // convert from feet/min to meter/s
1166
1167         double verticalDistance  = ((altitude_ft - 2000.0) - trafficRef->getArrivalAirport()->getElevation()) *SG_FEET_TO_METER;
1168         double descentTimeNeeded = verticalDistance / descentRate;
1169         double distanceCovered   = descentSpeed * descentTimeNeeded;
1170
1171         //cerr << "Tracking  : " << fgGetString("/ai/track-callsign");
1172         if (trafficRef->getCallSign() == fgGetString("/ai/track-callsign")) {
1173             cerr << "Checking for end of cruise stage for :" << trafficRef->getCallSign() << endl;
1174             cerr << "Descent rate      : " << descentRate << endl;
1175             cerr << "Descent speed     : " << descentSpeed << endl;
1176             cerr << "VerticalDistance  : " << verticalDistance << ". Altitude : " << altitude_ft << ". Elevation " << trafficRef->getArrivalAirport()->getElevation() << endl;
1177             cerr << "DecentTimeNeeded  : " << descentTimeNeeded << endl;
1178             cerr << "DistanceCovered   : " << distanceCovered   << endl;
1179         }
1180         //cerr << "Distance = " << distance << endl;
1181         distance = distanceCovered;
1182         if (dist < distanceCovered) {
1183               if (trafficRef->getCallSign() == fgGetString("/ai/track-callsign")) {
1184                    //exit(1);
1185               }
1186               return true;
1187         } else {
1188               return false;
1189         }
1190     } else {
1191          return false;
1192     }
1193 }
1194
1195 void FGAIAircraft::resetPositionFromFlightPlan()
1196 {
1197     // the one behind you
1198     FGAIFlightPlan::waypoint* prev = 0;
1199     // the one ahead
1200     FGAIFlightPlan::waypoint* curr = 0;
1201     // the next plus 1
1202     FGAIFlightPlan::waypoint* next = 0;
1203
1204     prev = fp->getPreviousWaypoint();
1205     curr = fp->getCurrentWaypoint();
1206     next = fp->getNextWaypoint();
1207
1208     setLatitude(prev->latitude);
1209     setLongitude(prev->longitude);
1210     double tgt_heading = fp->getBearing(curr, next);
1211     setHeading(tgt_heading);
1212     setAltitude(prev->altitude);
1213     setSpeed(prev->speed);
1214 }
1215
1216 double FGAIAircraft::getBearing(double crse)
1217 {
1218   double hdgDiff = fabs(hdg-crse);
1219   if (hdgDiff > 180)
1220       hdgDiff = fabs(hdgDiff - 360);
1221   return hdgDiff;
1222 }
1223
1224 time_t FGAIAircraft::checkForArrivalTime(string wptName) {
1225      FGAIFlightPlan::waypoint* curr = 0;
1226      curr = fp->getCurrentWaypoint();
1227
1228      double tracklength = fp->checkTrackLength(wptName);
1229      if (tracklength > 0.1) {
1230           tracklength += fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
1231      } else {
1232          return 0;
1233      }
1234      time_t now = time(NULL) + fgGetLong("/sim/time/warp");
1235      time_t arrivalTime = fp->getArrivalTime();
1236
1237      time_t ete = tracklength / ((speed * SG_NM_TO_METER) / 3600.0);
1238      time_t secondsToGo = arrivalTime - now;
1239      if (trafficRef->getCallSign() == fgGetString("/ai/track-callsign")) {
1240           cerr << "Checking arrival time: ete " << ete << ". Time to go : " << secondsToGo << ". Track length = " << tracklength << endl;
1241      }
1242      return (ete - secondsToGo); // Positive when we're too slow...
1243 }