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/math/point3d.hxx>
  26 #include <simgear/route/waypoint.hxx>
  27 #include <Main/fg_props.hxx>
  28 #include <Main/globals.hxx>
  29 #include <Main/viewer.hxx>
  30 #include <Scenery/scenery.hxx>
  31 #include <Scenery/tilemgr.hxx>
  32
  33 #include <string>
  34 #include <math.h>
  35 #include <time.h>
  36 #ifdef _MSC_VER
  37 #  include <float.h>
  38 #  define finite _finite
  39 #elif defined(__sun) || defined(sgi)
  40 #  include <ieeefp.h>
  41 #endif
  42
  43 SG_USING_STD(string);
  44
  45 #include "AIAircraft.hxx"
  46    static string tempReg;
  47 //
  48 // accel, decel, climb_rate, descent_rate, takeoff_speed, climb_speed,
  49 // cruise_speed, descent_speed, land_speed
  50 //
  51 const FGAIAircraft::PERF_STRUCT FGAIAircraft::settings[] = {
  52     // light aircraft
  53     {2.0, 2.0,  450.0, 1000.0,  70.0,  80.0, 100.0,  80.0,  60.0},
  54     // ww2_fighter
  55     {4.0, 2.0, 3000.0, 1500.0, 110.0, 180.0, 250.0, 200.0, 100.0},
  56     // jet_transport
  57     {5.0, 2.0, 3000.0, 1500.0, 140.0, 300.0, 430.0, 300.0, 130.0},
  58     // jet_fighter
  59     {7.0, 3.0, 4000.0, 2000.0, 150.0, 350.0, 500.0, 350.0, 150.0},
  60     // tanker
  61     {5.0, 2.0, 3000.0, 1500.0, 140.0, 300.0, 430.0, 300.0, 130.0},
  62     // ufo (extreme accel/decel)
  63     {30.0, 30.0, 6000.0, 6000.0, 150.0, 300.0, 430.0, 300.0, 130.0}
  64 };
  65
  66
  67 FGAIAircraft::FGAIAircraft(FGAISchedule *ref) :
  68     FGAIBase(otAircraft)
  69 {
  70     trafficRef = ref;
  71     if (trafficRef)
  72         groundOffset = trafficRef->getGroundOffset();
  73     else
  74         groundOffset = 0;
  75
  76     fp = 0;
  77     dt_count = 0;
  78     dt_elev_count = 0;
  79     use_perf_vs = true;
  80     isTanker = false;
  81
  82     // set heading and altitude locks
  83     hdg_lock = false;
  84     alt_lock = false;
  85     roll = 0;
  86     headingChangeRate = 0.0;
  87 }
  88
  89
  90 FGAIAircraft::~FGAIAircraft() {
  91     //delete fp;
  92 }
  93
  94
  95 void FGAIAircraft::readFromScenario(SGPropertyNode* scFileNode) {
  96     if (!scFileNode)
  97         return;
  98
  99     FGAIBase::readFromScenario(scFileNode);
 100
 101     setPerformance(scFileNode->getStringValue("class", "jet_transport"));
 102     setFlightPlan(scFileNode->getStringValue("flightplan"),
 103                   scFileNode->getBoolValue("repeat", false));
 104     setCallSign(scFileNode->getStringValue("callsign"));
 105     setTACANChannelID(scFileNode->getStringValue("TACAN-channel-ID"));
 106 }
 107
 108
 109 bool FGAIAircraft::init() {
 110     //refuel_node = fgGetNode("systems/refuel/contact", true);
 111     return FGAIBase::init();
 112 }
 113
 114
 115 void FGAIAircraft::bind() {
 116     FGAIBase::bind();
 117
 118     props->tie("controls/gear/gear-down",
 119                SGRawValueMethods<FGAIAircraft,bool>(*this,
 120                                               &FGAIAircraft::_getGearDown));
 121     props->tie("refuel/contact", SGRawValuePointer<bool>(&contact));
 122     props->setStringValue("callsign", callsign.c_str());
 123     props->setStringValue("navaids/tacan/channel-ID", TACAN_channel_id.c_str());
 124     props->setBoolValue("tanker",isTanker);
 125 }
 126
 127
 128 void FGAIAircraft::unbind() {
 129     FGAIBase::unbind();
 130
 131     props->untie("controls/gear/gear-down");
 132     props->untie("refuel/contact");
 133 }
 134
 135
 136 void FGAIAircraft::update(double dt) {
 137     FGAIBase::update(dt);
 138     Run(dt);
 139     Transform();
 140 }
 141
 142
 143 void FGAIAircraft::setPerformance(const std::string& acclass) {
 144     if (acclass == "light") {
 145         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::LIGHT]);
 146     } else if (acclass == "ww2_fighter") {
 147         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::WW2_FIGHTER]);
 148     } else if (acclass == "jet_transport") {
 149         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::JET_TRANSPORT]);
 150     } else if (acclass == "jet_fighter") {
 151         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::JET_FIGHTER]);
 152     } else if (acclass == "tanker") {
 153         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::JET_TRANSPORT]);
 154         SetTanker(true);
 155     } else if (acclass == "ufo") {
 156         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::UFO]);
 157     } else {
 158         SetPerformance(&FGAIAircraft::settings[FGAIAircraft::JET_TRANSPORT]);
 159     }
 160 }
 161
 162
 163 void FGAIAircraft::SetPerformance(const PERF_STRUCT *ps) {
 164
 165    performance = ps;
 166 }
 167
 168
 169 void FGAIAircraft::Run(double dt) {
 170
 171     FGAIAircraft::dt = dt;
 172
 173     if (fp) {
 174         time_t now = time(NULL) + fgGetLong("/sim/time/warp");
 175         ProcessFlightPlan(dt, now);
 176         if (now < fp->getStartTime()) {
 177             // Do execute Ground elev for inactive aircraft, so they
 178             // Are repositioned to the correct ground altitude when the user flies within visibility range.
 179             if (no_roll) {
 180                 Transform();       // make sure aip is initialized.
 181                 getGroundElev(dt); // make sure it's exectuted first time around, so force a large dt value
 182                 //getGroundElev(dt); // Need to do this twice.
 183                 //cerr << trafficRef->getRegistration() << " Setting altitude to " << tgt_altitude;
 184                 doGroundAltitude();
 185                 //cerr << " Actual altitude " << altitude << endl;
 186                 // Transform();
 187                 pos.setElevationFt(altitude_ft);
 188             }
 189             return;
 190         }
 191     } else {
 192         // no flight plan, update target heading, speed, and altitude
 193         // from control properties.  These default to the initial
 194         // settings in the config file, but can be changed "on the
 195         // fly".
 196
 197         string lat_mode = props->getStringValue("controls/flight/lateral-mode");
 198         if ( lat_mode == "roll" ) {
 199             double angle
 200                 = props->getDoubleValue("controls/flight/target-roll" );
 201             RollTo( angle );
 202         } else {
 203              double angle
 204                 = props->getDoubleValue("controls/flight/target-hdg" );
 205             TurnTo( angle );
 206         }
 207
 208         string lon_mode
 209             = props->getStringValue("controls/flight/longitude-mode");
 210         if ( lon_mode == "alt" ) {
 211             double alt = props->getDoubleValue("controls/flight/target-alt" );
 212             ClimbTo( alt );
 213         } else {
 214             double angle
 215                 = props->getDoubleValue("controls/flight/target-pitch" );
 216             PitchTo( angle );
 217         }
 218
 219         AccelTo( props->getDoubleValue("controls/flight/target-spd" ) );
 220     }
 221
 222     double turn_radius_ft;
 223     double turn_circum_ft;
 224     double speed_north_deg_sec;
 225     double speed_east_deg_sec;
 226     double dist_covered_ft;
 227     double alpha;
 228
 229     // adjust speed
 230     double speed_diff; //= tgt_speed - speed;
 231     if (!no_roll) {
 232         speed_diff = tgt_speed - speed;
 233     } else {
 234         speed_diff = groundTargetSpeed - speed;
 235     }
 236     if (fabs(speed_diff) > 0.2) {
 237         if (speed_diff > 0.0)
 238             speed += performance->accel * dt;
 239         if (speed_diff < 0.0) {
 240             if (no_roll) { // was (!no_roll) but seems more logical this way (ground brakes).
 241                 speed -= performance->decel * dt * 3;
 242             } else {
 243                 speed -= performance->decel * dt;
 244             }
 245         }
 246     }
 247
 248     // convert speed to degrees per second
 249     speed_north_deg_sec = cos( hdg / SG_RADIANS_TO_DEGREES )
 250                           * speed * 1.686 / ft_per_deg_lat;
 251     speed_east_deg_sec  = sin( hdg / SG_RADIANS_TO_DEGREES )
 252                           * speed * 1.686 / ft_per_deg_lon;
 253
 254     // set new position
 255     pos.setLatitudeDeg( pos.getLatitudeDeg() + speed_north_deg_sec * dt);
 256     pos.setLongitudeDeg( pos.getLongitudeDeg() + speed_east_deg_sec * dt);
 257     //if (!(finite(pos.lat()) && finite(pos.lon())))
 258     //  {
 259     //    cerr << "Position is not finite" << endl;
 260     //    cerr << "speed = " << speed << endl;
 261     //    cerr << "dt" << dt << endl;
 262     //    cerr << "heading " << hdg << endl;
 263     //    cerr << "speed east " << speed_east_deg_sec << endl;
 264     //    cerr << "speed nrth " << speed_north_deg_sec << endl;
 265     //    cerr << "deg_lat    " << ft_per_deg_lat << endl;
 266     //    cerr << "deg_lon    " << ft_per_deg_lon << endl;
 267     //  }
 268
 269     // adjust heading based on current bank angle
 270     if (roll == 0.0)
 271         roll = 0.01;
 272
 273     if (roll != 0.0) {
 274         // double turnConstant;
 275         //if (no_roll)
 276         //  turnConstant = 0.0088362;
 277         //else
 278         //  turnConstant = 0.088362;
 279         // If on ground, calculate heading change directly
 280         if (no_roll) {
 281             double headingDiff = fabs(hdg-tgt_heading);
 282
 283             if (headingDiff > 180)
 284                 headingDiff = fabs(headingDiff - 360);
 285
 286             groundTargetSpeed = tgt_speed - (tgt_speed * (headingDiff/45));
 287             if (sign(groundTargetSpeed) != sign(tgt_speed))
 288                 groundTargetSpeed = 0.21 * sign(tgt_speed); // to prevent speed getting stuck in 'negative' mode
 289
 290             if (headingDiff > 30.0) {
 291                 headingChangeRate += dt * sign(roll); // invert if pushed backward
 292                 // Print some debug statements to find out why aircraft may get stuck
 293                 // forever turning
 294                 //if (trafficRef->getDepartureAirport()->getId() == string("EHAM")) {
 295                 //    cerr << "Turning : " << trafficRef->getRegistration()
 296                 //    cerr <<  " Speed = " << speed << " Heading " << hdg
 297                 //         << " Target Heading " << tgt_heading
 298                 //         << " Lead Distance " <<  fp->getLeadDistance()
 299                 //         << " Distance to go "
 300                 //         << fp->getDistanceToGo(pos.lat(), pos.lon(), fp->getCurrentWaypoint())
 301                 //         << "waypoint name " << fp->getCurrentWaypoint()->name
 302                 //         << endl;
 303                 //}
 304                 if (headingChangeRate > 30)
 305                     headingChangeRate = 30;
 306                 else if (headingChangeRate < -30)
 307                     headingChangeRate = -30;
 308
 309             } else {
 310                 if (fabs(headingChangeRate) > headingDiff)
 311                     headingChangeRate = headingDiff*sign(roll);
 312                 else
 313                     headingChangeRate += dt * sign(roll);
 314             }
 315             hdg += headingChangeRate * dt;
 316             //cerr << "On ground. Heading: " << hdg << ". Target Heading: " << tgt_heading
 317             //     << ". Target speed: " << groundTargetSpeed << ". heading change rate"
 318             //     << headingChangeRate << endl;
 319
 320         } else {
 321             if (fabs(speed) > 1.0) {
 322                 turn_radius_ft = 0.088362 * speed * speed
 323                         / tan( fabs(roll) / SG_RADIANS_TO_DEGREES );
 324             } else {
 325                 turn_radius_ft = 1.0; // Check if turn_radius_ft == 0; this might lead to a division by 0.
 326             }
 327             turn_circum_ft = SGD_2PI * turn_radius_ft;
 328             dist_covered_ft = speed * 1.686 * dt;
 329             alpha = dist_covered_ft / turn_circum_ft * 360.0;
 330             hdg += alpha * sign(roll);
 331         }
 332         while ( hdg > 360.0 ) {
 333             hdg -= 360.0;
 334             spinCounter++;
 335         }
 336         while ( hdg < 0.0) {
 337             hdg += 360.0;
 338             spinCounter--;
 339         }
 340     }
 341
 342
 343     // adjust target bank angle if heading lock engaged
 344     if (hdg_lock) {
 345         double bank_sense = 0.0;
 346         double diff = fabs(hdg - tgt_heading);
 347         if (diff > 180)
 348             diff = fabs(diff - 360);
 349
 350         double sum = hdg + diff;
 351         if (sum > 360.0)
 352             sum -= 360.0;
 353         if (fabs(sum - tgt_heading) < 1.0) {
 354             bank_sense = 1.0;   // right turn
 355         } else {
 356             bank_sense = -1.0;  // left turn
 357         }
 358         if (diff < 30) {
 359             tgt_roll = diff * bank_sense;
 360         } else {
 361             tgt_roll = 30.0 * bank_sense;
 362         }
 363         if ((fabs((double) spinCounter) > 1) && (diff > 30)) {
 364             tgt_speed *= 0.999; // Ugly hack: If aircraft get stuck, they will continually spin around.
 365             // The only way to resolve this is to make them slow down.
 366             //if (tempReg.empty())
 367             //  tempReg = trafficRef->getRegistration();
 368             //if (trafficRef->getRegistration() == tempReg) {
 369             //    cerr << trafficRef->getRegistration()
 370             //         << " appears to be spinning: " << spinCounter << endl
 371             //         << " speed          " << speed << endl
 372             //         << " heading        " << hdg << endl
 373             //         << " lead distance  " << fp->getLeadDistance() << endl
 374             //         << " waypoint       " << fp->getCurrentWaypoint()->name
 375             //         << " target heading " << tgt_heading << endl
 376             //         << " lead in angle  " << fp->getLeadInAngle()<< endl
 377             //         << " roll           " << roll << endl
 378             //         << " target_roll    " << tgt_roll << endl;
 379             //}
 380         }
 381     }
 382
 383     // adjust bank angle, use 9 degrees per second
 384     double bank_diff = tgt_roll - roll;
 385     if (fabs(bank_diff) > 0.2) {
 386         if (bank_diff > 0.0)
 387             roll += 9.0 * dt;
 388
 389         if (bank_diff < 0.0)
 390             roll -= 9.0 * dt;
 391         //while (roll > 180) roll -= 360;
 392         //while (roll < 180) roll += 360;
 393     }
 394
 395     // adjust altitude (meters) based on current vertical speed (fpm)
 396     altitude_ft += vs / 60.0 * dt;
 397     pos.setElevationFt(altitude_ft);
 398
 399     // adjust target Altitude, based on ground elevation when on ground
 400     if (no_roll) {
 401         getGroundElev(dt);
 402         doGroundAltitude();
 403     } else {
 404         // find target vertical speed if altitude lock engaged
 405         if (alt_lock && use_perf_vs) {
 406             if (altitude_ft < tgt_altitude_ft) {
 407                 tgt_vs = tgt_altitude_ft - altitude_ft;
 408                 if (tgt_vs > performance->climb_rate)
 409                     tgt_vs = performance->climb_rate;
 410             } else {
 411                 tgt_vs = tgt_altitude_ft - altitude_ft;
 412                 if (tgt_vs  < (-performance->descent_rate))
 413                     tgt_vs = -performance->descent_rate;
 414             }
 415         }
 416
 417         if (alt_lock && !use_perf_vs) {
 418             double max_vs = 4*(tgt_altitude_ft - altitude_ft);
 419             double min_vs = 100;
 420             if (tgt_altitude_ft < altitude_ft)
 421                 min_vs = -100.0;
 422             if ((fabs(tgt_altitude_ft - altitude_ft) < 1500.0)
 423                     && (fabs(max_vs) < fabs(tgt_vs)))
 424                 tgt_vs = max_vs;
 425
 426             if (fabs(tgt_vs) < fabs(min_vs))
 427                 tgt_vs = min_vs;
 428         }
 429     }
 430     // adjust vertical speed
 431     double vs_diff = tgt_vs - vs;
 432     if (fabs(vs_diff) > 10.0) {
 433         if (vs_diff > 0.0) {
 434             vs += 900.0 * dt;
 435
 436             if (vs > tgt_vs)
 437                 vs = tgt_vs;
 438         } else {
 439             vs -= 400.0 * dt;
 440
 441            if (vs < tgt_vs)
 442                vs = tgt_vs;
 443         }
 444     }
 445
 446     // match pitch angle to vertical speed
 447     if (vs > 0) {
 448         pitch = vs * 0.005;
 449     } else {
 450         pitch = vs * 0.002;
 451     }
 452
 453     //###########################//
 454     // do calculations for radar //
 455     //###########################//
 456     double range_ft2 = UpdateRadar(manager);
 457
 458     //************************************//
 459     // Tanker code                        //
 460     //************************************//
 461
 462     if ( isTanker) {
 463         if ( (range_ft2 < 250.0 * 250.0) && (y_shift > 0.0)
 464                 && (elevation > 0.0) ) {
 465             //refuel_node->setBoolValue(true);
 466             contact = true;
 467         } else {
 468             //refuel_node->setBoolValue(false);
 469             contact = false;
 470         }
 471     } else {
 472         contact = false;
 473     }
 474 }
 475
 476
 477 void FGAIAircraft::AccelTo(double speed) {
 478     tgt_speed = speed;
 479 }
 480
 481
 482 void FGAIAircraft::PitchTo(double angle) {
 483     tgt_pitch = angle;
 484     alt_lock = false;
 485 }
 486
 487
 488 void FGAIAircraft::RollTo(double angle) {
 489     tgt_roll = angle;
 490     hdg_lock = false;
 491 }
 492
 493
 494 void FGAIAircraft::YawTo(double angle) {
 495     tgt_yaw = angle;
 496 }
 497
 498
 499 void FGAIAircraft::ClimbTo(double alt_ft ) {
 500     tgt_altitude_ft = alt_ft;
 501     alt_lock = true;
 502 }
 503
 504
 505 void FGAIAircraft::TurnTo(double heading) {
 506     tgt_heading = heading;
 507     hdg_lock = true;
 508 }
 509
 510
 511 double FGAIAircraft::sign(double x) {
 512     if ( x < 0.0 )
 513         return -1.0;
 514     else
 515         return 1.0;
 516 }
 517
 518
 519 void FGAIAircraft::setFlightPlan(const std::string& flightplan, bool repeat) {
 520     if (!flightplan.empty()) {
 521         FGAIFlightPlan* fp = new FGAIFlightPlan(flightplan);
 522         fp->setRepeat(repeat);
 523         SetFlightPlan(fp);
 524     }
 525 }
 526
 527
 528 void FGAIAircraft::SetFlightPlan(FGAIFlightPlan *f) {
 529     delete fp;
 530     fp = f;
 531 }
 532
 533
 534 void FGAIAircraft::ProcessFlightPlan( double dt, time_t now ) {
 535     bool eraseWaypoints;
 536     if (trafficRef) {
 537 //      FGAirport *arr;
 538 //      FGAirport *dep;
 539         eraseWaypoints = true;
 540 //      cerr << trafficRef->getRegistration();
 541 //      cerr << "Departure airport " << endl;
 542 //      dep = trafficRef->getDepartureAirport();
 543 //      if (dep)
 544 //          cerr << dep->getId() << endl;
 545 //      cerr << "Arrival   airport " << endl;
 546 //      arr = trafficRef->getArrivalAirport();
 547 //      if (arr)
 548 //          cerr << arr->getId() <<endl << endl;;
 549     } else
 550         eraseWaypoints = false;
 551
 552     //cerr << "Processing Flightplan" << endl;
 553     FGAIFlightPlan::waypoint* prev = 0; // the one behind you
 554     FGAIFlightPlan::waypoint* curr = 0; // the one ahead
 555     FGAIFlightPlan::waypoint* next = 0; // the next plus 1
 556     prev = fp->getPreviousWaypoint();
 557     curr = fp->getCurrentWaypoint();
 558     next = fp->getNextWaypoint();
 559     dt_count += dt;
 560
 561     if (!prev) {  //beginning of flightplan, do this initialization once
 562         //setBank(0.0);
 563         spinCounter = 0;
 564         tempReg = "";
 565         //prev_dist_to_go = HUGE;
 566         //cerr << "Before increment " << curr-> name << endl;
 567         fp->IncrementWaypoint(eraseWaypoints);
 568         //prev = fp->getPreviousWaypoint(); //first waypoint
 569         //curr = fp->getCurrentWaypoint();  //second waypoint
 570         //next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 571         //cerr << "After increment " << prev-> name << endl;
 572         if (!(fp->getNextWaypoint()) && trafficRef)
 573             loadNextLeg();
 574
 575         //cerr << "After load " << prev-> name << endl;
 576         prev = fp->getPreviousWaypoint(); //first waypoint
 577         curr = fp->getCurrentWaypoint();  //second waypoint
 578         next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 579         //cerr << "After load " << prev-> name << endl;
 580         setLatitude(prev->latitude);
 581         setLongitude(prev->longitude);
 582         setSpeed(prev->speed);
 583         setAltitude(prev->altitude);
 584
 585         if (prev->speed > 0.0)
 586             setHeading(fp->getBearing(prev->latitude, prev->longitude, curr));
 587         else
 588             setHeading(fp->getBearing(curr->latitude, curr->longitude, prev));
 589
 590         // If next doesn't exist, as in incrementally created flightplans for
 591         // AI/Trafficmanager created plans,
 592         // Make sure lead distance is initialized otherwise
 593         if (next)
 594             fp->setLeadDistance(speed, hdg, curr, next);
 595
 596         if (curr->crossat > -1000.0) { //use a calculated descent/climb rate
 597             use_perf_vs = false;
 598             tgt_vs = (curr->crossat - prev->altitude)
 599                     / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 600                     / 6076.0 / prev->speed*60.0);
 601             tgt_altitude_ft = curr->crossat;
 602         } else {
 603             use_perf_vs = true;
 604             tgt_altitude_ft = prev->altitude;
 605         }
 606         alt_lock = hdg_lock = true;
 607         no_roll = prev->on_ground;
 608         if (no_roll) {
 609             Transform();         // make sure aip is initialized.
 610             getGroundElev(60.1); // make sure it's exectuted first time around, so force a large dt value
 611             //getGroundElev(60.1); // Need to do this twice.
 612             //cerr << trafficRef->getRegistration() << " Setting altitude to " << tgt_altitude << endl;
 613             doGroundAltitude(); //(tgt_altitude);
 614         }
 615         prevSpeed = 0;
 616         //cout << "First waypoint:  " << prev->name << endl;
 617         //cout << "  Target speed:    " << tgt_speed << endl;
 618         //cout << "  Target altitude: " << tgt_altitude << endl;
 619         //cout << "  Target heading:  " << tgt_heading << endl << endl;
 620         //cerr << "Done Flightplan init" << endl;
 621         return;
 622     } // end of initialization
 623
 624     // let's only process the flight plan every 100 ms.
 625     if ((dt_count < 0.1) || (now < fp->getStartTime())) {
 626         //cerr  << "done fp dt" << endl;
 627         return;
 628     } else {
 629         dt_count = 0;
 630     }
 631     // check to see if we've reached the lead point for our next turn
 632     double dist_to_go = fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 633
 634     //cerr << "2" << endl;
 635     double lead_dist = fp->getLeadDistance();
 636     //cerr << " Distance : " << dist_to_go << ": Lead distance " << lead_dist << endl;
 637     // experimental: Use fabs, because speed can be negative (I hope) during push_back.
 638
 639     if (lead_dist < fabs(2*speed)) {
 640         lead_dist = fabs(2*speed);  //don't skip over the waypoint
 641         //cerr << "Extending lead distance to " << lead_dist << endl;
 642     }
 643 //  FGAirport * apt = trafficRef->getDepartureAirport();
 644 //  if ((dist_to_go > prev_dist_to_go) && trafficRef && apt) {
 645 //      if (apt->getId() == string("EHAM"))
 646 //          cerr << "Alert: " << trafficRef->getRegistration() << " is moving away from waypoint " << curr->name  << endl
 647 //               << "Target heading : " << tgt_heading << "act heading " << hdg << " Tgt speed : " << tgt_speed << endl
 648 //               << "Lead distance : " << lead_dist  << endl
 649 //               << "Distance to go: " << dist_to_go << endl;
 650 //  }
 651
 652     prev_dist_to_go = dist_to_go;
 653     //cerr << "2" << endl;
 654     //if (no_roll)
 655     //  lead_dist = 10.0;
 656     //cout << "Leg : " << (fp->getLeg()-1) << ". dist_to_go: " << dist_to_go << ",  lead_dist: "
 657     //     << lead_dist << ", tgt_speed " << tgt_speed << ", tgt_heading " << tgt_heading
 658     //     << " speed " << speed << " hdg " << hdg << ". Altitude "  << altitude << " TAget alt :"
 659     //     << tgt_altitude << endl;
 660
 661     if ( dist_to_go < lead_dist ) {
 662         //prev_dist_to_go = HUGE;
 663         // For traffic manager generated aircraft:
 664         // check if the aircraft flies of of user range. And adjust the
 665         // Current waypoint's elevation according to Terrain Elevation
 666         if (curr->finished) {  //end of the flight plan
 667             if (fp->getRepeat())
 668                 fp->restart();
 669             else
 670                 setDie(true);
 671
 672             //cerr << "Done die end of fp" << endl;
 673             return;
 674         }
 675
 676         // we've reached the lead-point for the waypoint ahead
 677         //cerr << "4" << endl;
 678         //cerr << "Situation after lead point" << endl;
 679         //cerr << "Prviious: " << prev->name << endl;
 680         //cerr << "Current : " << curr->name << endl;
 681         //cerr << "Next    : " << next->name << endl;
 682         if (next) {
 683             tgt_heading = fp->getBearing(curr, next);
 684             spinCounter = 0;
 685         }
 686
 687         fp->IncrementWaypoint(eraseWaypoints);
 688         if (!(fp->getNextWaypoint()) && trafficRef)
 689             loadNextLeg();
 690
 691         prev = fp->getPreviousWaypoint();
 692         curr = fp->getCurrentWaypoint();
 693         next = fp->getNextWaypoint();
 694
 695         // Now that we have incremented the waypoints, excute some traffic manager specific code
 696         // based on the name of the waypoint we just passed.
 697         if (trafficRef) {
 698             double userLatitude  = fgGetDouble("/position/latitude-deg");
 699             double userLongitude = fgGetDouble("/position/longitude-deg");
 700             double course, distance;
 701             SGWayPoint current(pos.getLongitudeDeg(), pos.getLatitudeDeg(), 0);
 702             SGWayPoint user (userLongitude, userLatitude, 0);
 703             user.CourseAndDistance(current, &course, &distance);
 704             if ((distance * SG_METER_TO_NM) > TRAFFICTOAIDIST) {
 705                 setDie(true);
 706                 //cerr << "done fp die out of range" << endl;
 707                 return;
 708             }
 709
 710             FGAirport * dep = trafficRef->getDepartureAirport();
 711             FGAirport * arr = trafficRef->getArrivalAirport();
 712             // At parking the beginning of the airport
 713             if (!( dep && arr)) {
 714                 setDie(true);
 715                 return;
 716             }
 717
 718             //if ((dep->getId() == string("EHAM") || (arr->getId() == string("EHAM")))) {
 719             //    cerr << trafficRef->getRegistration()
 720             //         << " Enroute from " << dep->getId()
 721             //         << " to "           << arr->getId()
 722             //         << " just crossed " << prev->name
 723             //         << " Assigned rwy     " << fp->getRunwayId()
 724             //         << " " << fp->getRunway() << endl;
 725             // }
 726             //if ((dep->getId() == string("EHAM")) && (prev->name == "park2")) {
 727             //    cerr << "Schiphol ground "
 728             //         << trafficRef->getCallSign();
 729             //    if (trafficRef->getHeavy())
 730             //        cerr << "Heavy";
 731             //    cerr << ", is type "
 732             //         << trafficRef->getAircraft()
 733             //         << " ready to go. IFR to "
 734             //         << arr->getId() <<endl;
 735             // }
 736
 737             if (prev->name == "park2")
 738                 dep->getDynamics()->releaseParking(fp->getGate());
 739
 740             // Some debug messages, specific to testing the Logical networks.
 741             // if ((arr->getId() == string("EHAM")) && (prev->name  == "Center")) {
 742             //     cerr << "Schiphol ground "
 743             //          << trafficRef->getRegistration() << " "
 744             //          << trafficRef->getCallSign();
 745             //     if (trafficRef->getHeavy())
 746             //         cerr << "Heavy";
 747             //     cerr << ", arriving from " << dep->getName() ;
 748             //     cerr << " landed runway "
 749             //          << fp->getRunway()
 750             //          << " request taxi to gate "
 751             //          << arr->getDynamics()->getParkingName(fp->getGate())
 752             //          << endl;
 753             // }
 754             if (prev->name == "END")
 755                 fp->setTime(trafficRef->getDepartureTime());
 756             //cerr << "5" << endl;
 757         }
 758
 759         if (next) {
 760             //cerr << "Current waypoint" << curr->name << endl;
 761             //cerr << "Next waypoint" << next->name << endl;
 762             fp->setLeadDistance(speed, tgt_heading, curr, next);
 763         }
 764
 765         //cerr << "5.1" << endl;
 766         if (!(prev->on_ground)) { // only update the tgt altitude from flightplan if not on the ground
 767             tgt_altitude_ft = prev->altitude;
 768             if (curr->crossat > -1000.0) {
 769                 //cerr << "5.1a" << endl;
 770                 use_perf_vs = false;
 771                 tgt_vs = (curr->crossat - altitude_ft) / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 772                         / 6076.0 / speed*60.0);
 773                 //cerr << "5.1b" << endl;
 774                 tgt_altitude_ft = curr->crossat;
 775             } else {
 776                 //cerr << "5.1c" << endl;
 777                 use_perf_vs = true;
 778                 //cerr << "5.1d" << endl;
 779                 //cerr << "Setting target altitude : " <<tgt_altitude_ft << endl;
 780             }
 781         }
 782         //cerr << "6" << endl;
 783         tgt_speed = prev->speed;
 784         hdg_lock = alt_lock = true;
 785         no_roll = prev->on_ground;
 786         //cout << "Crossing waypoint: " << prev->name << endl;
 787         //cout << "  Target speed:    " << tgt_speed << endl;
 788         //cout << "  Target altitude: " << tgt_altitude_ft << endl;
 789         //cout << "  Target heading:  " << tgt_heading << endl << endl;
 790
 791     } else {
 792         double calc_bearing = fp->getBearing(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 793         //cerr << "Bearing = " << calc_bearing << endl;
 794         if (speed < 0) {
 795             calc_bearing +=180;
 796             if (calc_bearing > 360)
 797                 calc_bearing -= 360;
 798         }
 799
 800         if (finite(calc_bearing)) {
 801             double hdg_error = calc_bearing - tgt_heading;
 802             if (fabs(hdg_error) > 1.0) {
 803                 TurnTo( calc_bearing );
 804             }
 805
 806         } else {
 807             cerr << "calc_bearing is not a finite number : "
 808                  << "Speed " << speed
 809                  << "pos : " << pos.getLatitudeDeg() << ", " << pos.getLongitudeDeg()
 810                  << "waypoint " << curr->latitude << ", " << curr->longitude << endl;
 811             cerr << "waypoint name " << curr->name;
 812             exit(1);  // FIXME
 813         }
 814
 815         double speed_diff = speed - prevSpeed;
 816         // Update the lead distance calculation if speed has changed sufficiently
 817         // to prevent spinning (hopefully);
 818         if (fabs(speed_diff) > 10) {
 819             prevSpeed = speed;
 820             fp->setLeadDistance(speed, tgt_heading, curr, next);
 821         }
 822
 823         //cerr << "Done Processing FlightPlan"<< endl;
 824     }
 825 }
 826
 827
 828 bool FGAIAircraft::_getGearDown() const {
 829     return ((props->getFloatValue("position/altitude-agl-ft") < 900.0)
 830             && (props->getFloatValue("velocities/airspeed-kt")
 831             < performance->land_speed*1.25));
 832 }
 833
 834
 835 void FGAIAircraft::loadNextLeg() {
 836     //delete fp;
 837     //time_t now = time(NULL) + fgGetLong("/sim/time/warp");
 838
 839     //FGAIModelEntity entity;
 840     //entity.m_class = "jet_transport";
 841     //entity.path = modelPath.c_str();
 842     //entity.flightplan = "none";
 843     //entity.latitude = _getLatitude();
 844     //entity.longitude = _getLongitude();
 845     //entity.altitude = trafficRef->getCruiseAlt() * 100; // convert from FL to feet
 846     //entity.speed = 450; // HACK ALERT
 847     //entity.fp = new FGAIFlightPlan(&entity, courseToDest, i->getDepartureTime(), dep, arr);
 848     int leg;
 849     if ((leg = fp->getLeg())  == 10) {
 850         trafficRef->next();
 851         leg = 1;
 852         fp->setLeg(leg);
 853         //cerr << "Resetting leg : " << leg << endl;
 854     }
 855     //leg++;
 856     //fp->setLeg(leg);
 857     //cerr << "Creating leg number : " << leg << endl;
 858     FGAirport *dep = trafficRef->getDepartureAirport();
 859     FGAirport *arr = trafficRef->getArrivalAirport();
 860     if (!(dep && arr)) {
 861         setDie(true);
 862         //cerr << "Failed to get airport in AIAircraft::ProcessFlightplan()" << endl;
 863         //if (dep)
 864         //  cerr << "Departure " << dep->getId() << endl;
 865         //if (arr)
 866         //  cerr << "Arrival   " << arr->getId() << endl;
 867
 868     } else {
 869         double cruiseAlt = trafficRef->getCruiseAlt() * 100;
 870         //cerr << "Creating new leg using " << cruiseAlt << " as cruise altitude."<< endl;
 871
 872         fp->create (dep,
 873                     arr,
 874                     leg,
 875                     cruiseAlt, //(trafficRef->getCruiseAlt() * 100), // convert from FL to feet
 876                     trafficRef->getSpeed(),
 877                     _getLatitude(),
 878                     _getLongitude(),
 879                     false,
 880                     trafficRef->getRadius(),
 881                     trafficRef->getFlightType(),
 882                     acType,
 883                     company);
 884         //prev = fp->getPreviousWaypoint();
 885         //curr = fp->getCurrentWaypoint();
 886         //next = fp->getNextWaypoint();
 887         //cerr << "25" << endl;
 888         //if (next)
 889         //        {
 890         //  //cerr << "Next waypoint" << next->name << endl;
 891         //          fp->setLeadDistance(speed, tgt_heading, curr, next);
 892         //        }
 893         //cerr << "25.1" << endl;
 894         //if (curr->crossat > -1000.0) {
 895         //        //cerr << "25.1a" << endl;
 896         //        use_perf_vs = false;
 897         //
 898         //        tgt_vs = (curr->crossat - altitude_ft)/
 899         //          (fp->getDistanceToGo(pos.lat(), pos.lon(), curr)/6076.0/speed*60.0);
 900         //        //cerr << "25.1b" << endl;
 901         //        tgt_altitude_ft = curr->crossat;
 902         //} else {
 903         //        //cerr << "25.1c" << endl;
 904         //        use_perf_vs = true;
 905         //        //cerr << "25.1d" << endl;
 906         //        tgt_altitude_ft = prev->altitude;
 907         //        //cerr << "Setting target altitude : " <<tgt_altitude_ft << endl;
 908         // }
 909         //cerr << "26" << endl;
 910         //tgt_speed = prev->speed;
 911         //hdg_lock = alt_lock = true;
 912         //no_roll = prev->on_ground;
 913     }
 914     //else
 915     //{
 916     //delete entity.fp;
 917     //entity.fp = new FGAIFlightPlan(&entity,
 918     //                                 999,  // A hack
 919     //                                 trafficRef->getDepartureTime(),
 920     //                                 trafficRef->getDepartureAirport(),
 921     //                                 trafficRef->getArrivalAirport(),
 922     //                                 false,
 923     //                                 acType,
 924     //                                 company);
 925     //SetFlightPlan(entity.fp);
 926 }
 927
 928
 929 // Note: This code is copied from David Luff's AILocalTraffic
 930 // Warning - ground elev determination is CPU intensive
 931 // Either this function or the logic of how often it is called
 932 // will almost certainly change.
 933
 934 void FGAIAircraft::getGroundElev(double dt) {
 935     dt_elev_count += dt;
 936
 937     // Update minimally every three secs, but add some randomness
 938     // to prevent all IA objects doing this in synchrony
 939     if (dt_elev_count < (3.0) + (rand() % 10))
 940         return;
 941     else
 942        dt_elev_count = 0;
 943
 944     // Only do the proper hitlist stuff if we are within visible range of the viewer.
 945     if (!invisible) {
 946         double visibility_meters = fgGetDouble("/environment/visibility-m");
 947
 948         FGViewer* vw = globals->get_current_view();
 949         double course, distance;
 950
 951         SGWayPoint current(pos.getLongitudeDeg(), pos.getLatitudeDeg(), 0);
 952         SGWayPoint view (vw->getLongitude_deg(), vw->getLatitude_deg(), 0);
 953         view.CourseAndDistance(current, &course, &distance);
 954         if(distance > visibility_meters) {
 955             //aip.getSGLocation()->set_cur_elev_m(aptElev);
 956             return;
 957         }
 958
 959         // FIXME: make sure the pos.lat/pos.lon values are in degrees ...
 960         double range = 500.0;
 961         if (!globals->get_tile_mgr()->scenery_available(pos.getLatitudeDeg(), pos.getLongitudeDeg(), range)) {
 962             // Try to shedule tiles for that position.
 963             globals->get_tile_mgr()->update( aip.getSGLocation(), range );
 964         }
 965
 966         // FIXME: make sure the pos.lat/pos.lon values are in degrees ...
 967         double alt;
 968         if (globals->get_scenery()->get_elevation_m(pos.getLatitudeDeg(), pos.getLongitudeDeg(), 20000.0, alt, 0))
 969             tgt_altitude_ft = alt * SG_METER_TO_FEET;
 970
 971         //cerr << "Target altitude : " << tgt_altitude_ft << endl;
 972         // if (globals->get_scenery()->get_elevation_m(pos.lat(), pos.lon(),
 973         //                                            20000.0, alt))
 974         //    tgt_altitude_ft = alt * SG_METER_TO_FEET;
 975         //cerr << "Target altitude : " << tgt_altitude_ft << endl;
 976     }
 977 }
 978
 979
 980 void FGAIAircraft::setCallSign(const string& s) {
 981     callsign = s;
 982 }
 983
 984
 985 void FGAIAircraft::setTACANChannelID(const string& id) {
 986     TACAN_channel_id = id;
 987 }
 988
 989
 990 void FGAIAircraft::doGroundAltitude() {
 991    if (fabs(altitude_ft - (tgt_altitude_ft+groundOffset)) > 1000.0)
 992        altitude_ft = (tgt_altitude_ft + groundOffset);
 993    else
 994       altitude_ft += 0.1 * ((tgt_altitude_ft+groundOffset) - altitude_ft);
 995 }
 996