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         string lat_mode = props->getStringValue("controls/flight/lateral-mode");
 197         if ( lat_mode == "roll" ) {
 198             double angle
 199                 = props->getDoubleValue("controls/flight/target-roll" );
 200             RollTo( angle );
 201         } else {
 202              double angle
 203                 = props->getDoubleValue("controls/flight/target-hdg" );
 204             TurnTo( angle );
 205         }
 206
 207         string lon_mode
 208             = props->getStringValue("controls/flight/longitude-mode");
 209         if ( lon_mode == "alt" ) {
 210             double alt = props->getDoubleValue("controls/flight/target-alt" );
 211             ClimbTo( alt );
 212         } else {
 213             double angle
 214                 = props->getDoubleValue("controls/flight/target-pitch" );
 215             PitchTo( angle );
 216         }
 217
 218         AccelTo( props->getDoubleValue("controls/flight/target-spd" ) );
 219     }
 220
 221     double turn_radius_ft;
 222     double turn_circum_ft;
 223     double speed_north_deg_sec;
 224     double speed_east_deg_sec;
 225     double dist_covered_ft;
 226     double alpha;
 227
 228     // adjust speed
 229     double speed_diff; //= tgt_speed - speed;
 230     if (!no_roll) {
 231         speed_diff = tgt_speed - speed;
 232     } else {
 233         speed_diff = groundTargetSpeed - speed;
 234     }
 235
 236     if (speed_diff > 0.0) {
 237         speed += performance->accel * dt;
 238         if (no_roll) { // apply overshoot correction
 239           if ( speed > groundTargetSpeed ) speed = groundTargetSpeed;
 240         }else {
 241           if ( speed > tgt_speed ) speed = tgt_speed;
 242         }
 243     } else if (speed_diff < 0.0) {
 244         if (no_roll) {
 245             // on ground (aircraft can't roll)
 246             // deceleration performance is better due to wheel brakes.
 247             speed -= performance->decel * dt * 3;
 248         } else {
 249             speed -= performance->decel * dt;
 250         }
 251         if (no_roll) { // apply overshoot correction
 252         if (speed < groundTargetSpeed ) speed = groundTargetSpeed;
 253         } else {
 254           if ( speed < tgt_speed ) speed = tgt_speed;
 255         }
 256     }
 257
 258
 259     // convert speed to degrees per second
 260     speed_north_deg_sec = cos( hdg * SGD_DEGREES_TO_RADIANS )
 261                           * speed * 1.686 / ft_per_deg_lat;
 262     speed_east_deg_sec  = sin( hdg * SGD_DEGREES_TO_RADIANS )
 263                           * speed * 1.686 / ft_per_deg_lon;
 264
 265     // set new position
 266     pos.setLatitudeDeg( pos.getLatitudeDeg() + speed_north_deg_sec * dt);
 267     pos.setLongitudeDeg( pos.getLongitudeDeg() + speed_east_deg_sec * dt);
 268
 269     /* printf("%.7f %0.4f %.7f %.5f %.7f %.7f %.8f %.8f %.9f %.9f\n",
 270            dt, hdg, speed, ft_per_deg_lat,
 271            cos( hdg * SGD_DEGREES_TO_RADIANS ),
 272            speed * 1.686 / ft_per_deg_lat,
 273            speed_north_deg_sec, speed_east_deg_sec,
 274            pos.getLatitudeDeg(), pos.getLongitudeDeg()); */
 275
 276     //if (!(finite(pos.lat()) && finite(pos.lon())))
 277     //  {
 278     //    cerr << "Position is not finite" << endl;
 279     //    cerr << "speed = " << speed << endl;
 280     //    cerr << "dt" << dt << endl;
 281     //    cerr << "heading " << hdg << endl;
 282     //    cerr << "speed east " << speed_east_deg_sec << endl;
 283     //    cerr << "speed nrth " << speed_north_deg_sec << endl;
 284     //    cerr << "deg_lat    " << ft_per_deg_lat << endl;
 285     //    cerr << "deg_lon    " << ft_per_deg_lon << endl;
 286     //  }
 287
 288     // adjust heading based on current bank angle
 289     if (roll == 0.0)
 290         roll = 0.01;
 291
 292     if (roll != 0.0) {
 293         // double turnConstant;
 294         //if (no_roll)
 295         //  turnConstant = 0.0088362;
 296         //else
 297         //  turnConstant = 0.088362;
 298         // If on ground, calculate heading change directly
 299         if (no_roll) {
 300             double headingDiff = fabs(hdg-tgt_heading);
 301
 302             if (headingDiff > 180)
 303                 headingDiff = fabs(headingDiff - 360);
 304
 305             groundTargetSpeed = tgt_speed - (tgt_speed * (headingDiff/45));
 306             if (sign(groundTargetSpeed) != sign(tgt_speed))
 307                 groundTargetSpeed = 0.21 * sign(tgt_speed); // to prevent speed getting stuck in 'negative' mode
 308
 309             if (headingDiff > 30.0) {
 310                 headingChangeRate += dt * sign(roll); // invert if pushed backward
 311                 // Print some debug statements to find out why aircraft may get stuck
 312                 // forever turning
 313                 //if (trafficRef->getDepartureAirport()->getId() == string("EHAM")) {
 314                 //    cerr << "Turning : " << trafficRef->getRegistration()
 315                 //    cerr <<  " Speed = " << speed << " Heading " << hdg
 316                 //         << " Target Heading " << tgt_heading
 317                 //         << " Lead Distance " <<  fp->getLeadDistance()
 318                 //         << " Distance to go "
 319                 //         << fp->getDistanceToGo(pos.lat(), pos.lon(), fp->getCurrentWaypoint())
 320                 //         << "waypoint name " << fp->getCurrentWaypoint()->name
 321                 //         << endl;
 322                 //}
 323                 if (headingChangeRate > 30)
 324                     headingChangeRate = 30;
 325                 else if (headingChangeRate < -30)
 326                     headingChangeRate = -30;
 327
 328             } else {
 329                 if (fabs(headingChangeRate) > headingDiff)
 330                     headingChangeRate = headingDiff*sign(roll);
 331                 else
 332                     headingChangeRate += dt * sign(roll);
 333             }
 334             hdg += headingChangeRate * dt;
 335             //cerr << "On ground. Heading: " << hdg << ". Target Heading: " << tgt_heading
 336             //     << ". Target speed: " << groundTargetSpeed << ". heading change rate"
 337             //     << headingChangeRate << endl;
 338
 339         } else {
 340             if (fabs(speed) > 1.0) {
 341                 turn_radius_ft = 0.088362 * speed * speed
 342                         / tan( fabs(roll) / SG_RADIANS_TO_DEGREES );
 343             } else {
 344                 turn_radius_ft = 1.0; // Check if turn_radius_ft == 0; this might lead to a division by 0.
 345             }
 346             turn_circum_ft = SGD_2PI * turn_radius_ft;
 347             dist_covered_ft = speed * 1.686 * dt;
 348             alpha = dist_covered_ft / turn_circum_ft * 360.0;
 349             hdg += alpha * sign(roll);
 350         }
 351         while ( hdg > 360.0 ) {
 352             hdg -= 360.0;
 353             spinCounter++;
 354         }
 355         while ( hdg < 0.0) {
 356             hdg += 360.0;
 357             spinCounter--;
 358         }
 359     }
 360
 361
 362     // adjust target bank angle if heading lock engaged
 363     if (hdg_lock) {
 364         double bank_sense = 0.0;
 365         double diff = fabs(hdg - tgt_heading);
 366         if (diff > 180)
 367             diff = fabs(diff - 360);
 368
 369         double sum = hdg + diff;
 370         if (sum > 360.0)
 371             sum -= 360.0;
 372         if (fabs(sum - tgt_heading) < 1.0) {
 373             bank_sense = 1.0;   // right turn
 374         } else {
 375             bank_sense = -1.0;  // left turn
 376         }
 377         if (diff < 30) {
 378             tgt_roll = diff * bank_sense;
 379         } else {
 380             tgt_roll = 30.0 * bank_sense;
 381         }
 382         if ((fabs((double) spinCounter) > 1) && (diff > 30)) {
 383             tgt_speed *= 0.999; // Ugly hack: If aircraft get stuck, they will continually spin around.
 384             // The only way to resolve this is to make them slow down.
 385             //if (tempReg.empty())
 386             //  tempReg = trafficRef->getRegistration();
 387             //if (trafficRef->getRegistration() == tempReg) {
 388             //    cerr << trafficRef->getRegistration()
 389             //         << " appears to be spinning: " << spinCounter << endl
 390             //         << " speed          " << speed << endl
 391             //         << " heading        " << hdg << endl
 392             //         << " lead distance  " << fp->getLeadDistance() << endl
 393             //         << " waypoint       " << fp->getCurrentWaypoint()->name
 394             //         << " target heading " << tgt_heading << endl
 395             //         << " lead in angle  " << fp->getLeadInAngle()<< endl
 396             //         << " roll           " << roll << endl
 397             //         << " target_roll    " << tgt_roll << endl;
 398             //}
 399         }
 400     }
 401
 402     // adjust bank angle, use 9 degrees per second
 403     double bank_diff = tgt_roll - roll;
 404     if (fabs(bank_diff) > 0.2) {
 405         if (bank_diff > 0.0)
 406             roll += 9.0 * dt;
 407
 408         if (bank_diff < 0.0)
 409             roll -= 9.0 * dt;
 410         //while (roll > 180) roll -= 360;
 411         //while (roll < 180) roll += 360;
 412     }
 413
 414     // adjust altitude (meters) based on current vertical speed (fpm)
 415     altitude_ft += vs / 60.0 * dt;
 416     pos.setElevationFt(altitude_ft);
 417
 418     // adjust target Altitude, based on ground elevation when on ground
 419     if (no_roll) {
 420         getGroundElev(dt);
 421         doGroundAltitude();
 422     } else {
 423         // find target vertical speed if altitude lock engaged
 424         if (alt_lock && use_perf_vs) {
 425             if (altitude_ft < tgt_altitude_ft) {
 426                 tgt_vs = tgt_altitude_ft - altitude_ft;
 427                 if (tgt_vs > performance->climb_rate)
 428                     tgt_vs = performance->climb_rate;
 429             } else {
 430                 tgt_vs = tgt_altitude_ft - altitude_ft;
 431                 if (tgt_vs  < (-performance->descent_rate))
 432                     tgt_vs = -performance->descent_rate;
 433             }
 434         }
 435
 436         if (alt_lock && !use_perf_vs) {
 437             double max_vs = 4*(tgt_altitude_ft - altitude_ft);
 438             double min_vs = 100;
 439             if (tgt_altitude_ft < altitude_ft)
 440                 min_vs = -100.0;
 441             if ((fabs(tgt_altitude_ft - altitude_ft) < 1500.0)
 442                     && (fabs(max_vs) < fabs(tgt_vs)))
 443                 tgt_vs = max_vs;
 444
 445             if (fabs(tgt_vs) < fabs(min_vs))
 446                 tgt_vs = min_vs;
 447         }
 448     }
 449     // adjust vertical speed
 450     double vs_diff = tgt_vs - vs;
 451     if (fabs(vs_diff) > 10.0) {
 452         if (vs_diff > 0.0) {
 453             vs += 900.0 * dt;
 454
 455             if (vs > tgt_vs)
 456                 vs = tgt_vs;
 457         } else {
 458             vs -= 400.0 * dt;
 459
 460            if (vs < tgt_vs)
 461                vs = tgt_vs;
 462         }
 463     }
 464
 465     // match pitch angle to vertical speed
 466     if (vs > 0) {
 467         pitch = vs * 0.005;
 468     } else {
 469         pitch = vs * 0.002;
 470     }
 471
 472     //###########################//
 473     // do calculations for radar //
 474     //###########################//
 475     double range_ft2 = UpdateRadar(manager);
 476
 477     //************************************//
 478     // Tanker code                        //
 479     //************************************//
 480
 481     if ( isTanker) {
 482         if ( (range_ft2 < 250.0 * 250.0) && (y_shift > 0.0)
 483                 && (elevation > 0.0) ) {
 484             //refuel_node->setBoolValue(true);
 485             contact = true;
 486         } else {
 487             //refuel_node->setBoolValue(false);
 488             contact = false;
 489         }
 490     } else {
 491         contact = false;
 492     }
 493 }
 494
 495
 496 void FGAIAircraft::AccelTo(double speed) {
 497     tgt_speed = speed;
 498 }
 499
 500
 501 void FGAIAircraft::PitchTo(double angle) {
 502     tgt_pitch = angle;
 503     alt_lock = false;
 504 }
 505
 506
 507 void FGAIAircraft::RollTo(double angle) {
 508     tgt_roll = angle;
 509     hdg_lock = false;
 510 }
 511
 512
 513 void FGAIAircraft::YawTo(double angle) {
 514     tgt_yaw = angle;
 515 }
 516
 517
 518 void FGAIAircraft::ClimbTo(double alt_ft ) {
 519     tgt_altitude_ft = alt_ft;
 520     alt_lock = true;
 521 }
 522
 523
 524 void FGAIAircraft::TurnTo(double heading) {
 525     tgt_heading = heading;
 526     hdg_lock = true;
 527 }
 528
 529
 530 double FGAIAircraft::sign(double x) {
 531     if ( x < 0.0 )
 532         return -1.0;
 533     else
 534         return 1.0;
 535 }
 536
 537
 538 void FGAIAircraft::setFlightPlan(const std::string& flightplan, bool repeat) {
 539     if (!flightplan.empty()) {
 540         FGAIFlightPlan* fp = new FGAIFlightPlan(flightplan);
 541         fp->setRepeat(repeat);
 542         SetFlightPlan(fp);
 543     }
 544 }
 545
 546
 547 void FGAIAircraft::SetFlightPlan(FGAIFlightPlan *f) {
 548     delete fp;
 549     fp = f;
 550 }
 551
 552
 553 void FGAIAircraft::ProcessFlightPlan( double dt, time_t now ) {
 554     bool eraseWaypoints;
 555     if (trafficRef) {
 556 //      FGAirport *arr;
 557 //      FGAirport *dep;
 558         eraseWaypoints = true;
 559 //      cerr << trafficRef->getRegistration();
 560 //      cerr << "Departure airport " << endl;
 561 //      dep = trafficRef->getDepartureAirport();
 562 //      if (dep)
 563 //          cerr << dep->getId() << endl;
 564 //      cerr << "Arrival   airport " << endl;
 565 //      arr = trafficRef->getArrivalAirport();
 566 //      if (arr)
 567 //          cerr << arr->getId() <<endl << endl;;
 568     } else
 569         eraseWaypoints = false;
 570
 571     //cerr << "Processing Flightplan" << endl;
 572     FGAIFlightPlan::waypoint* prev = 0; // the one behind you
 573     FGAIFlightPlan::waypoint* curr = 0; // the one ahead
 574     FGAIFlightPlan::waypoint* next = 0; // the next plus 1
 575     prev = fp->getPreviousWaypoint();
 576     curr = fp->getCurrentWaypoint();
 577     next = fp->getNextWaypoint();
 578     dt_count += dt;
 579
 580     if (!prev) {  //beginning of flightplan, do this initialization once
 581         //setBank(0.0);
 582         spinCounter = 0;
 583         tempReg = "";
 584         //prev_dist_to_go = HUGE;
 585         //cerr << "Before increment " << curr-> name << endl;
 586         fp->IncrementWaypoint(eraseWaypoints);
 587         //prev = fp->getPreviousWaypoint(); //first waypoint
 588         //curr = fp->getCurrentWaypoint();  //second waypoint
 589         //next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 590         //cerr << "After increment " << prev-> name << endl;
 591         if (!(fp->getNextWaypoint()) && trafficRef)
 592             loadNextLeg();
 593
 594         //cerr << "After load " << prev-> name << endl;
 595         prev = fp->getPreviousWaypoint(); //first waypoint
 596         curr = fp->getCurrentWaypoint();  //second waypoint
 597         next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 598         //cerr << "After load " << prev-> name << endl;
 599         setLatitude(prev->latitude);
 600         setLongitude(prev->longitude);
 601         setSpeed(prev->speed);
 602         setAltitude(prev->altitude);
 603
 604         if (prev->speed > 0.0)
 605             setHeading(fp->getBearing(prev->latitude, prev->longitude, curr));
 606         else
 607             setHeading(fp->getBearing(curr->latitude, curr->longitude, prev));
 608
 609         // If next doesn't exist, as in incrementally created flightplans for
 610         // AI/Trafficmanager created plans,
 611         // Make sure lead distance is initialized otherwise
 612         if (next)
 613             fp->setLeadDistance(speed, hdg, curr, next);
 614
 615         if (curr->crossat > -1000.0) { //use a calculated descent/climb rate
 616             use_perf_vs = false;
 617             tgt_vs = (curr->crossat - prev->altitude)
 618                     / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 619                     / 6076.0 / prev->speed*60.0);
 620             tgt_altitude_ft = curr->crossat;
 621         } else {
 622             use_perf_vs = true;
 623             tgt_altitude_ft = prev->altitude;
 624         }
 625         alt_lock = hdg_lock = true;
 626         no_roll = prev->on_ground;
 627         if (no_roll) {
 628             Transform();         // make sure aip is initialized.
 629             getGroundElev(60.1); // make sure it's exectuted first time around, so force a large dt value
 630             //getGroundElev(60.1); // Need to do this twice.
 631             //cerr << trafficRef->getRegistration() << " Setting altitude to " << tgt_altitude << endl;
 632             doGroundAltitude(); //(tgt_altitude);
 633         }
 634         prevSpeed = 0;
 635         //cout << "First waypoint:  " << prev->name << endl;
 636         //cout << "  Target speed:    " << tgt_speed << endl;
 637         //cout << "  Target altitude: " << tgt_altitude << endl;
 638         //cout << "  Target heading:  " << tgt_heading << endl << endl;
 639         //cerr << "Done Flightplan init" << endl;
 640         return;
 641     } // end of initialization
 642
 643     // let's only process the flight plan every 100 ms.
 644     if ((dt_count < 0.1) || (now < fp->getStartTime())) {
 645         //cerr  << "done fp dt" << endl;
 646         return;
 647     } else {
 648         dt_count = 0;
 649     }
 650     // check to see if we've reached the lead point for our next turn
 651     double dist_to_go = fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 652
 653     //cerr << "2" << endl;
 654     double lead_dist = fp->getLeadDistance();
 655     //cerr << " Distance : " << dist_to_go << ": Lead distance " << lead_dist << endl;
 656     // experimental: Use fabs, because speed can be negative (I hope) during push_back.
 657
 658     if (lead_dist < fabs(2*speed)) {
 659         lead_dist = fabs(2*speed);  //don't skip over the waypoint
 660         //cerr << "Extending lead distance to " << lead_dist << endl;
 661     }
 662 //  FGAirport * apt = trafficRef->getDepartureAirport();
 663 //  if ((dist_to_go > prev_dist_to_go) && trafficRef && apt) {
 664 //      if (apt->getId() == string("EHAM"))
 665 //          cerr << "Alert: " << trafficRef->getRegistration() << " is moving away from waypoint " << curr->name  << endl
 666 //               << "Target heading : " << tgt_heading << "act heading " << hdg << " Tgt speed : " << tgt_speed << endl
 667 //               << "Lead distance : " << lead_dist  << endl
 668 //               << "Distance to go: " << dist_to_go << endl;
 669 //  }
 670
 671     prev_dist_to_go = dist_to_go;
 672     //cerr << "2" << endl;
 673     //if (no_roll)
 674     //  lead_dist = 10.0;
 675     //cout << "Leg : " << (fp->getLeg()-1) << ". dist_to_go: " << dist_to_go << ",  lead_dist: "
 676     //     << lead_dist << ", tgt_speed " << tgt_speed << ", tgt_heading " << tgt_heading
 677     //     << " speed " << speed << " hdg " << hdg << ". Altitude "  << altitude << " TAget alt :"
 678     //     << tgt_altitude << endl;
 679
 680     if ( dist_to_go < lead_dist ) {
 681         //prev_dist_to_go = HUGE;
 682         // For traffic manager generated aircraft:
 683         // check if the aircraft flies of of user range. And adjust the
 684         // Current waypoint's elevation according to Terrain Elevation
 685         if (curr->finished) {  //end of the flight plan
 686             if (fp->getRepeat())
 687                 fp->restart();
 688             else
 689                 setDie(true);
 690
 691             //cerr << "Done die end of fp" << endl;
 692             return;
 693         }
 694
 695         // we've reached the lead-point for the waypoint ahead
 696         //cerr << "4" << endl;
 697         //cerr << "Situation after lead point" << endl;
 698         //cerr << "Prviious: " << prev->name << endl;
 699         //cerr << "Current : " << curr->name << endl;
 700         //cerr << "Next    : " << next->name << endl;
 701         if (next) {
 702             tgt_heading = fp->getBearing(curr, next);
 703             spinCounter = 0;
 704         }
 705
 706         fp->IncrementWaypoint(eraseWaypoints);
 707         if (!(fp->getNextWaypoint()) && trafficRef)
 708             loadNextLeg();
 709
 710         prev = fp->getPreviousWaypoint();
 711         curr = fp->getCurrentWaypoint();
 712         next = fp->getNextWaypoint();
 713
 714         // Now that we have incremented the waypoints, excute some traffic manager specific code
 715         // based on the name of the waypoint we just passed.
 716         if (trafficRef) {
 717             double userLatitude  = fgGetDouble("/position/latitude-deg");
 718             double userLongitude = fgGetDouble("/position/longitude-deg");
 719             double course, distance;
 720             SGWayPoint current(pos.getLongitudeDeg(), pos.getLatitudeDeg(), 0);
 721             SGWayPoint user (userLongitude, userLatitude, 0);
 722             user.CourseAndDistance(current, &course, &distance);
 723             if ((distance * SG_METER_TO_NM) > TRAFFICTOAIDIST) {
 724                 setDie(true);
 725                 //cerr << "done fp die out of range" << endl;
 726                 return;
 727             }
 728
 729             FGAirport * dep = trafficRef->getDepartureAirport();
 730             FGAirport * arr = trafficRef->getArrivalAirport();
 731             // At parking the beginning of the airport
 732             if (!( dep && arr)) {
 733                 setDie(true);
 734                 return;
 735             }
 736
 737             //if ((dep->getId() == string("EHAM") || (arr->getId() == string("EHAM")))) {
 738             //    cerr << trafficRef->getRegistration()
 739             //         << " Enroute from " << dep->getId()
 740             //         << " to "           << arr->getId()
 741             //         << " just crossed " << prev->name
 742             //         << " Assigned rwy     " << fp->getRunwayId()
 743             //         << " " << fp->getRunway() << endl;
 744             // }
 745             //if ((dep->getId() == string("EHAM")) && (prev->name == "park2")) {
 746             //    cerr << "Schiphol ground "
 747             //         << trafficRef->getCallSign();
 748             //    if (trafficRef->getHeavy())
 749             //        cerr << "Heavy";
 750             //    cerr << ", is type "
 751             //         << trafficRef->getAircraft()
 752             //         << " ready to go. IFR to "
 753             //         << arr->getId() <<endl;
 754             // }
 755
 756             if (prev->name == "park2")
 757                 dep->getDynamics()->releaseParking(fp->getGate());
 758
 759             // Some debug messages, specific to testing the Logical networks.
 760             // if ((arr->getId() == string("EHAM")) && (prev->name  == "Center")) {
 761             //     cerr << "Schiphol ground "
 762             //          << trafficRef->getRegistration() << " "
 763             //          << trafficRef->getCallSign();
 764             //     if (trafficRef->getHeavy())
 765             //         cerr << "Heavy";
 766             //     cerr << ", arriving from " << dep->getName() ;
 767             //     cerr << " landed runway "
 768             //          << fp->getRunway()
 769             //          << " request taxi to gate "
 770             //          << arr->getDynamics()->getParkingName(fp->getGate())
 771             //          << endl;
 772             // }
 773             if (prev->name == "END")
 774                 fp->setTime(trafficRef->getDepartureTime());
 775             //cerr << "5" << endl;
 776         }
 777
 778         if (next) {
 779             //cerr << "Current waypoint" << curr->name << endl;
 780             //cerr << "Next waypoint" << next->name << endl;
 781             fp->setLeadDistance(speed, tgt_heading, curr, next);
 782         }
 783
 784         //cerr << "5.1" << endl;
 785         if (!(prev->on_ground)) { // only update the tgt altitude from flightplan if not on the ground
 786             tgt_altitude_ft = prev->altitude;
 787             if (curr->crossat > -1000.0) {
 788                 //cerr << "5.1a" << endl;
 789                 use_perf_vs = false;
 790                 tgt_vs = (curr->crossat - altitude_ft) / (fp->getDistanceToGo(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr)
 791                         / 6076.0 / speed*60.0);
 792                 //cerr << "5.1b" << endl;
 793                 tgt_altitude_ft = curr->crossat;
 794             } else {
 795                 //cerr << "5.1c" << endl;
 796                 use_perf_vs = true;
 797                 //cerr << "5.1d" << endl;
 798                 //cerr << "Setting target altitude : " <<tgt_altitude_ft << endl;
 799             }
 800         }
 801         //cerr << "6" << endl;
 802         tgt_speed = prev->speed;
 803         hdg_lock = alt_lock = true;
 804         no_roll = prev->on_ground;
 805         //cout << "Crossing waypoint: " << prev->name << endl;
 806         //cout << "  Target speed:    " << tgt_speed << endl;
 807         //cout << "  Target altitude: " << tgt_altitude_ft << endl;
 808         //cout << "  Target heading:  " << tgt_heading << endl << endl;
 809
 810     } else {
 811         double calc_bearing = fp->getBearing(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr);
 812         //cerr << "Bearing = " << calc_bearing << endl;
 813         if (speed < 0) {
 814             calc_bearing +=180;
 815             if (calc_bearing > 360)
 816                 calc_bearing -= 360;
 817         }
 818
 819         if (finite(calc_bearing)) {
 820             double hdg_error = calc_bearing - tgt_heading;
 821             if (fabs(hdg_error) > 1.0) {
 822                 TurnTo( calc_bearing );
 823             }
 824
 825         } else {
 826             cerr << "calc_bearing is not a finite number : "
 827                  << "Speed " << speed
 828                  << "pos : " << pos.getLatitudeDeg() << ", " << pos.getLongitudeDeg()
 829                  << "waypoint " << curr->latitude << ", " << curr->longitude << endl;
 830             cerr << "waypoint name " << curr->name;
 831             exit(1);  // FIXME
 832         }
 833
 834         double speed_diff = speed - prevSpeed;
 835         // Update the lead distance calculation if speed has changed sufficiently
 836         // to prevent spinning (hopefully);
 837         if (fabs(speed_diff) > 10) {
 838             prevSpeed = speed;
 839             fp->setLeadDistance(speed, tgt_heading, curr, next);
 840         }
 841
 842         //cerr << "Done Processing FlightPlan"<< endl;
 843     }
 844 }
 845
 846
 847 bool FGAIAircraft::_getGearDown() const {
 848     return ((props->getFloatValue("position/altitude-agl-ft") < 900.0)
 849             && (props->getFloatValue("velocities/airspeed-kt")
 850             < performance->land_speed*1.25));
 851 }
 852
 853
 854 void FGAIAircraft::loadNextLeg() {
 855     //delete fp;
 856     //time_t now = time(NULL) + fgGetLong("/sim/time/warp");
 857
 858     //FGAIModelEntity entity;
 859     //entity.m_class = "jet_transport";
 860     //entity.path = modelPath.c_str();
 861     //entity.flightplan = "none";
 862     //entity.latitude = _getLatitude();
 863     //entity.longitude = _getLongitude();
 864     //entity.altitude = trafficRef->getCruiseAlt() * 100; // convert from FL to feet
 865     //entity.speed = 450; // HACK ALERT
 866     //entity.fp = new FGAIFlightPlan(&entity, courseToDest, i->getDepartureTime(), dep, arr);
 867     int leg;
 868     if ((leg = fp->getLeg())  == 10) {
 869         trafficRef->next();
 870         leg = 1;
 871         fp->setLeg(leg);
 872         //cerr << "Resetting leg : " << leg << endl;
 873     }
 874     //leg++;
 875     //fp->setLeg(leg);
 876     //cerr << "Creating leg number : " << leg << endl;
 877     FGAirport *dep = trafficRef->getDepartureAirport();
 878     FGAirport *arr = trafficRef->getArrivalAirport();
 879     if (!(dep && arr)) {
 880         setDie(true);
 881         //cerr << "Failed to get airport in AIAircraft::ProcessFlightplan()" << endl;
 882         //if (dep)
 883         //  cerr << "Departure " << dep->getId() << endl;
 884         //if (arr)
 885         //  cerr << "Arrival   " << arr->getId() << endl;
 886
 887     } else {
 888         double cruiseAlt = trafficRef->getCruiseAlt() * 100;
 889         //cerr << "Creating new leg using " << cruiseAlt << " as cruise altitude."<< endl;
 890
 891         fp->create (dep,
 892                     arr,
 893                     leg,
 894                     cruiseAlt, //(trafficRef->getCruiseAlt() * 100), // convert from FL to feet
 895                     trafficRef->getSpeed(),
 896                     _getLatitude(),
 897                     _getLongitude(),
 898                     false,
 899                     trafficRef->getRadius(),
 900                     trafficRef->getFlightType(),
 901                     acType,
 902                     company);
 903         //prev = fp->getPreviousWaypoint();
 904         //curr = fp->getCurrentWaypoint();
 905         //next = fp->getNextWaypoint();
 906         //cerr << "25" << endl;
 907         //if (next)
 908         //        {
 909         //  //cerr << "Next waypoint" << next->name << endl;
 910         //          fp->setLeadDistance(speed, tgt_heading, curr, next);
 911         //        }
 912         //cerr << "25.1" << endl;
 913         //if (curr->crossat > -1000.0) {
 914         //        //cerr << "25.1a" << endl;
 915         //        use_perf_vs = false;
 916         //
 917         //        tgt_vs = (curr->crossat - altitude_ft)/
 918         //          (fp->getDistanceToGo(pos.lat(), pos.lon(), curr)/6076.0/speed*60.0);
 919         //        //cerr << "25.1b" << endl;
 920         //        tgt_altitude_ft = curr->crossat;
 921         //} else {
 922         //        //cerr << "25.1c" << endl;
 923         //        use_perf_vs = true;
 924         //        //cerr << "25.1d" << endl;
 925         //        tgt_altitude_ft = prev->altitude;
 926         //        //cerr << "Setting target altitude : " <<tgt_altitude_ft << endl;
 927         // }
 928         //cerr << "26" << endl;
 929         //tgt_speed = prev->speed;
 930         //hdg_lock = alt_lock = true;
 931         //no_roll = prev->on_ground;
 932     }
 933     //else
 934     //{
 935     //delete entity.fp;
 936     //entity.fp = new FGAIFlightPlan(&entity,
 937     //                                 999,  // A hack
 938     //                                 trafficRef->getDepartureTime(),
 939     //                                 trafficRef->getDepartureAirport(),
 940     //                                 trafficRef->getArrivalAirport(),
 941     //                                 false,
 942     //                                 acType,
 943     //                                 company);
 944     //SetFlightPlan(entity.fp);
 945 }
 946
 947
 948 // Note: This code is copied from David Luff's AILocalTraffic
 949 // Warning - ground elev determination is CPU intensive
 950 // Either this function or the logic of how often it is called
 951 // will almost certainly change.
 952
 953 void FGAIAircraft::getGroundElev(double dt) {
 954     dt_elev_count += dt;
 955
 956     // Update minimally every three secs, but add some randomness
 957     // to prevent all IA objects doing this in synchrony
 958     if (dt_elev_count < (3.0) + (rand() % 10))
 959         return;
 960     else
 961        dt_elev_count = 0;
 962
 963     // Only do the proper hitlist stuff if we are within visible range of the viewer.
 964     if (!invisible) {
 965         double visibility_meters = fgGetDouble("/environment/visibility-m");
 966
 967         FGViewer* vw = globals->get_current_view();
 968         double course, distance;
 969
 970         SGWayPoint current(pos.getLongitudeDeg(), pos.getLatitudeDeg(), 0);
 971         SGWayPoint view (vw->getLongitude_deg(), vw->getLatitude_deg(), 0);
 972         view.CourseAndDistance(current, &course, &distance);
 973         if(distance > visibility_meters) {
 974             //aip.getSGLocation()->set_cur_elev_m(aptElev);
 975             return;
 976         }
 977
 978         // FIXME: make sure the pos.lat/pos.lon values are in degrees ...
 979         double range = 500.0;
 980         if (!globals->get_tile_mgr()->scenery_available(pos.getLatitudeDeg(), pos.getLongitudeDeg(), range)) {
 981             // Try to shedule tiles for that position.
 982             globals->get_tile_mgr()->update( aip.getSGLocation(), range );
 983         }
 984
 985         // FIXME: make sure the pos.lat/pos.lon values are in degrees ...
 986         double alt;
 987         if (globals->get_scenery()->get_elevation_m(pos.getLatitudeDeg(), pos.getLongitudeDeg(), 20000.0, alt, 0))
 988             tgt_altitude_ft = alt * SG_METER_TO_FEET;
 989
 990         //cerr << "Target altitude : " << tgt_altitude_ft << endl;
 991         // if (globals->get_scenery()->get_elevation_m(pos.lat(), pos.lon(),
 992         //                                            20000.0, alt))
 993         //    tgt_altitude_ft = alt * SG_METER_TO_FEET;
 994         //cerr << "Target altitude : " << tgt_altitude_ft << endl;
 995     }
 996 }
 997
 998
 999 void FGAIAircraft::setCallSign(const string& s) {
1000     callsign = s;
1001 }
1002
1003
1004 void FGAIAircraft::setTACANChannelID(const string& id) {
1005     TACAN_channel_id = id;
1006 }
1007
1008
1009 void FGAIAircraft::doGroundAltitude() {
1010    if (fabs(altitude_ft - (tgt_altitude_ft+groundOffset)) > 1000.0)
1011        altitude_ft = (tgt_altitude_ft + groundOffset);
1012    else
1013       altitude_ft += 0.1 * ((tgt_altitude_ft+groundOffset) - altitude_ft);
1014 }
1015