src/AIModel/AIShip.cxx

   1 // FGAIShip - FGAIBase-derived class creates an AI ship
   2 //
   3 // Written by David Culp, started October 2003.
   4 // with major amendments and additions by Vivian Meazza, 2004 - 2007
   5 //
   6 // This program is free software; you can redistribute it and/or
   7 // modify it under the terms of the GNU General Public License as
   8 // published by the Free Software Foundation; either version 2 of the
   9 // License, or (at your option) any later version.
  10 //
  11 // This program is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License
  17 // along with this program; if not, write to the Free Software
  18 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include <config.h>
  22 #endif
  23
  24 #ifdef _MSC_VER
  25 #  include <float.h>
  26 #  define finite _finite
  27 #elif defined(__sun) || defined(sgi)
  28 #  include <ieeefp.h>
  29 #endif
  30
  31 #include <math.h>
  32
  33 #include <simgear/sg_inlines.h>
  34 #include <simgear/math/sg_geodesy.hxx>
  35 #include <simgear/timing/sg_time.hxx>
  36 #include <simgear/math/sg_random.h>
  37
  38 #include <simgear/scene/util/SGNodeMasks.hxx>
  39 #include <Scenery/scenery.hxx>
  40
  41 #include "AIShip.hxx"
  42
  43
  44 FGAIShip::FGAIShip(object_type ot) :
  45 FGAIBase(ot),
  46 _limit(100),
  47 _elevation_m(0),
  48 _elevation_ft(0),
  49 _tow_angle(0),
  50 _dt_count(0),
  51 _next_run(0),
  52 _lead_angle(0),
  53 _xtrack_error(0),
  54 _tunnel(false),
  55 _initial_tunnel(false),
  56 _curr_alt(0),
  57 _prev_alt(0),
  58 _until_time(""),
  59 _fp_init(false),
  60 _missed(false),
  61 _waiting(false),
  62 _new_waypoint(true),
  63 _missed_count(0),
  64 _wait_count(0),
  65 _missed_time_sec(30),
  66 _day(86400),
  67 _wp_range(0),
  68 _old_range(0),
  69 _range_rate(0),
  70 _roll_constant(0.001),
  71 _hdg_constant(0.01),
  72 _roll_factor(-0.0083335),
  73 _restart(false)
  74
  75 {
  76         invisible = false;
  77 }
  78
  79 FGAIShip::~FGAIShip() {
  80 }
  81
  82 void FGAIShip::readFromScenario(SGPropertyNode* scFileNode) {
  83
  84     if (!scFileNode)
  85         return;
  86
  87     FGAIBase::readFromScenario(scFileNode);
  88
  89     setRudder(scFileNode->getFloatValue("rudder", 0.0));
  90     setName(scFileNode->getStringValue("name", "Titanic"));
  91     setRadius(scFileNode->getDoubleValue("turn-radius-ft", 2000));
  92     std::string flightplan = scFileNode->getStringValue("flightplan");
  93     setRepeat(scFileNode->getBoolValue("repeat", false));
  94     setRestart(scFileNode->getBoolValue("restart", false));
  95     setStartTime(scFileNode->getStringValue("time", ""));
  96     setLeadAngleGain(scFileNode->getDoubleValue("lead-angle-gain", 1.5));
  97     setLeadAngleLimit(scFileNode->getDoubleValue("lead-angle-limit-deg", 15));
  98     setLeadAngleProp(scFileNode->getDoubleValue("lead-angle-proportion", 0.75));
  99     setRudderConstant(scFileNode->getDoubleValue("rudder-constant", 0.5));
 100     setFixedTurnRadius(scFileNode->getDoubleValue("fixed-turn-radius-ft", 500));
 101     setSpeedConstant(scFileNode->getDoubleValue("speed-constant", 0.5));
 102
 103     if (!flightplan.empty()) {
 104         SG_LOG(SG_GENERAL, SG_ALERT, "getting flightplan: " << _name );
 105
 106         FGAIFlightPlan* fp = new FGAIFlightPlan(flightplan);
 107         setFlightPlan(fp);
 108     }
 109
 110 }
 111
 112 bool FGAIShip::init(bool search_in_AI_path) {
 113     prev = 0; // the one behind you
 114     curr = 0; // the one ahead
 115     next = 0; // the next plus 1
 116
 117     props->setStringValue("name", _name.c_str());
 118     props->setStringValue("waypoint/name-prev", _prev_name.c_str());
 119     props->setStringValue("waypoint/name-curr", _curr_name.c_str());
 120     props->setStringValue("waypoint/name-next", _next_name.c_str());
 121     props->setStringValue("submodels/path", _path.c_str());
 122     props->setStringValue("waypoint/start-time", _start_time.c_str());
 123     props->setStringValue("waypoint/wait-until-time", _until_time.c_str());
 124
 125     _hdg_lock = false;
 126     _rudder = 0.0;
 127     no_roll = false;
 128
 129     _rd_turn_radius_ft = _sp_turn_radius_ft = turn_radius_ft;
 130
 131     if (fp)
 132         _fp_init = initFlightPlan();
 133
 134     return FGAIBase::init(search_in_AI_path);
 135 }
 136
 137 void FGAIShip::bind() {
 138     FGAIBase::bind();
 139
 140     props->tie("surface-positions/rudder-pos-deg",
 141         SGRawValuePointer<float>(&_rudder));
 142     props->tie("controls/heading-lock",
 143         SGRawValuePointer<bool>(&_hdg_lock));
 144     props->tie("controls/tgt-speed-kts",
 145         SGRawValuePointer<double>(&tgt_speed));
 146     props->tie("controls/tgt-heading-degs",
 147         SGRawValuePointer<double>(&tgt_heading));
 148     props->tie("controls/constants/rudder",
 149         SGRawValuePointer<double>(&_rudder_constant));
 150     props->tie("controls/constants/roll-factor",
 151         SGRawValuePointer<double>(&_roll_factor));
 152     props->tie("controls/constants/roll",
 153         SGRawValuePointer<double>(&_roll_constant));
 154     props->tie("controls/constants/rudder",
 155         SGRawValuePointer<double>(&_rudder_constant));
 156     props->tie("controls/constants/speed",
 157         SGRawValuePointer<double>(&_speed_constant));
 158     props->tie("waypoint/range-nm",
 159         SGRawValuePointer<double>(&_wp_range));
 160     props->tie("waypoint/brg-deg",
 161         SGRawValuePointer<double>(&_course));
 162     props->tie("waypoint/rangerate-nm-sec",
 163         SGRawValuePointer<double>(&_range_rate));
 164     props->tie("waypoint/new",
 165         SGRawValuePointer<bool>(&_new_waypoint));
 166     props->tie("waypoint/missed",
 167         SGRawValuePointer<bool>(&_missed));
 168     props->tie("waypoint/missed-count-sec",
 169         SGRawValuePointer<double>(&_missed_count));
 170     props->tie("waypoint/missed-range-nm",
 171         SGRawValuePointer<double>(&_missed_range));
 172     props->tie("waypoint/missed-time-sec",
 173         SGRawValuePointer<double>(&_missed_time_sec));
 174     props->tie("waypoint/wait-count-sec",
 175         SGRawValuePointer<double>(&_wait_count));
 176     props->tie("waypoint/xtrack-error-ft",
 177         SGRawValuePointer<double>(&_xtrack_error));
 178     props->tie("waypoint/waiting",
 179         SGRawValuePointer<bool>(&_waiting));
 180     props->tie("waypoint/lead-angle-deg",
 181         SGRawValuePointer<double>(&_lead_angle));
 182     props->tie("waypoint/tunnel",
 183         SGRawValuePointer<bool>(&_tunnel));
 184     props->tie("waypoint/alt-curr-m",
 185         SGRawValuePointer<double>(&_curr_alt));
 186     props->tie("waypoint/alt-prev-m",
 187         SGRawValuePointer<double>(&_prev_alt));
 188     props->tie("submodels/serviceable",
 189         SGRawValuePointer<bool>(&_serviceable));
 190     props->tie("controls/turn-radius-ft",
 191         SGRawValuePointer<double>(&turn_radius_ft));
 192     props->tie("controls/turn-radius-corrected-ft",
 193         SGRawValuePointer<double>(&_rd_turn_radius_ft));
 194     props->tie("controls/constants/lead-angle/gain",
 195         SGRawValuePointer<double>(&_lead_angle_gain));
 196     props->tie("controls/constants/lead-angle/limit-deg",
 197         SGRawValuePointer<double>(&_lead_angle_limit));
 198     props->tie("controls/constants/lead-angle/proportion",
 199         SGRawValuePointer<double>(&_proportion));
 200     props->tie("controls/fixed-turn-radius-ft",
 201         SGRawValuePointer<double>(&_fixed_turn_radius));
 202     props->tie("controls/restart",
 203         SGRawValuePointer<bool>(&_restart));
 204     props->tie("velocities/speed-kts",
 205                 SGRawValuePointer<double>(&speed));
 206 }
 207
 208 void FGAIShip::unbind() {
 209     FGAIBase::unbind();
 210     props->untie("surface-positions/rudder-pos-deg");
 211     props->untie("controls/heading-lock");
 212     props->untie("controls/tgt-speed-kts");
 213     props->untie("controls/tgt-heading-degs");
 214     props->untie("controls/constants/roll");
 215     props->untie("controls/constants/rudder");
 216     props->untie("controls/constants/roll-factor");
 217     props->untie("controls/constants/speed");
 218     props->untie("waypoint/range-nm");
 219     props->untie("waypoint/range-brg-deg");
 220     props->untie("waypoint/rangerate-nm-sec");
 221     props->untie("waypoint/new");
 222     props->untie("waypoint/missed");
 223     props->untie("waypoint/missed-count-sec");
 224     props->untie("waypoint/missed-time-sec");
 225     props->untie("waypoint/missed-range");
 226     props->untie("waypoint/wait-count-sec");
 227     props->untie("waypoint/lead-angle-deg");
 228     props->untie("waypoint/xtrack-error-ft");
 229     props->untie("waypoint/waiting");
 230     props->untie("waypoint/tunnel");
 231     props->untie("waypoint/alt-curr-m");
 232     props->untie("waypoint/alt-prev-m");
 233     props->untie("submodels/serviceable");
 234     props->untie("controls/turn-radius-ft");
 235     props->untie("controls/turn-radius-corrected-ft");
 236     props->untie("controls/constants/lead-angle/gain");
 237     props->untie("controls/constants/lead-angle/limit-deg");
 238     props->untie("controls/constants/lead-angle/proportion");
 239     props->untie("controls/fixed-turn-radius-ft");
 240     props->untie("controls/constants/speed");
 241     props->untie("controls/restart");
 242     props->untie("velocities/speed-kts");
 243
 244 }
 245 void FGAIShip::update(double dt) {
 246     //SG_LOG(SG_GENERAL, SG_ALERT, "updating Ship: " << _name <<hdg<<pitch<<roll);
 247     // For computation of rotation speeds we just use finite differences here.
 248     // That is perfectly valid since this thing is not driven by accelerations
 249     // but by just apply discrete changes at its velocity variables.
 250     // Update the velocity information stored in those nodes.
 251     // Transform that one to the horizontal local coordinate system.
 252     SGQuatd ec2hl = SGQuatd::fromLonLat(pos);
 253     // The orientation of the carrier wrt the horizontal local frame
 254     SGQuatd hl2body = SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
 255     // and postrotate the orientation of the AIModel wrt the horizontal
 256     // local frame
 257     SGQuatd ec2body = ec2hl*hl2body;
 258     // The cartesian position of the carrier in the wgs84 world
 259     SGVec3d cartPos = SGVec3d::fromGeod(pos);
 260
 261     // The simulation time this transform is meant for
 262     aip.setReferenceTime(globals->get_sim_time_sec());
 263
 264     // Compute the velocity in m/s in the body frame
 265     aip.setBodyLinearVelocity(SGVec3d(0.51444444*speed, 0, 0));
 266
 267     FGAIBase::update(dt);
 268     Run(dt);
 269     Transform();
 270     if (fp)
 271         setXTrackError();
 272
 273     // Only change these values if we are able to compute them safely
 274     if (SGLimits<double>::min() < dt) {
 275         // Now here is the finite difference ...
 276
 277         // Transform that one to the horizontal local coordinate system.
 278         SGQuatd ec2hlNew = SGQuatd::fromLonLat(pos);
 279         // compute the new orientation
 280         SGQuatd hl2bodyNew = SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
 281         // The rotation difference
 282         SGQuatd dOr = inverse(ec2body)*ec2hlNew*hl2bodyNew;
 283         SGVec3d dOrAngleAxis;
 284         dOr.getAngleAxis(dOrAngleAxis);
 285         // divided by the time difference provides a rotation speed vector
 286         dOrAngleAxis /= dt;
 287
 288         aip.setBodyAngularVelocity(dOrAngleAxis);
 289     }
 290 }
 291
 292 void FGAIShip::Run(double dt) {
 293     if (_fp_init)
 294         ProcessFlightPlan(dt);
 295
 296     string type = getTypeString();
 297
 298     double alpha;
 299     double rudder_limit;
 300     double raw_roll;
 301
 302     // adjust speed
 303     double speed_diff = tgt_speed - speed;
 304
 305     if (fabs(speed_diff) > 0.1) {
 306
 307         if (speed_diff > 0.0)
 308             speed += _speed_constant * dt;
 309
 310         if (speed_diff < 0.0)
 311             speed -= _speed_constant * dt;
 312
 313     }
 314
 315     // do not allow unreasonable speeds
 316     SG_CLAMP_RANGE(speed, -_limit * 0.75, _limit);
 317
 318     // convert speed to degrees per second
 319     speed_north_deg_sec = cos(hdg / SGD_RADIANS_TO_DEGREES)
 320         * speed * 1.686 / ft_per_deg_lat;
 321     speed_east_deg_sec = sin(hdg / SGD_RADIANS_TO_DEGREES)
 322         * speed * 1.686 / ft_per_deg_lon;
 323
 324     // set new position
 325     //cout << _name << " " << type << " run: " << _elevation_m << " " <<_elevation_ft << endl;
 326     pos.setLatitudeDeg(pos.getLatitudeDeg() + speed_north_deg_sec * dt);
 327     pos.setLongitudeDeg(pos.getLongitudeDeg() + speed_east_deg_sec * dt);
 328     pos.setElevationFt(tgt_altitude_ft);
 329     pitch = tgt_pitch;
 330
 331     // adjust heading based on current _rudder angle
 332     if (turn_radius_ft <= 0)
 333         turn_radius_ft = 0; // don't allow nonsense values
 334
 335     if (_rudder > 45)
 336         _rudder = 45;
 337
 338     if (_rudder < -45)
 339         _rudder = -45;
 340
 341
 342     //we assume that at slow speed ships will manoeuvre using engines/bow thruster
 343         if(type == "ship" || type == "carrier" || type == "escort"){
 344
 345                 if (fabs(speed)<=5)
 346                         _sp_turn_radius_ft = _fixed_turn_radius;
 347                 else {
 348                         // adjust turn radius for speed. The equation is very approximate.
 349                         // we need to allow for negative speeds
 350                         _sp_turn_radius_ft = 10 * pow ((fabs(speed) - 15), 2) + turn_radius_ft;
 351                 }
 352
 353         } else {
 354
 355                 if (fabs(speed) <= 40)
 356            _sp_turn_radius_ft = _fixed_turn_radius;
 357                 else {
 358                         // adjust turn radius for speed.
 359                         _sp_turn_radius_ft = turn_radius_ft;
 360                 }
 361         }
 362
 363
 364     if (_rudder <= -0.25 || _rudder >= 0.25) {
 365         // adjust turn radius for _rudder angle. The equation is even more approximate.
 366         float a = 19;
 367         float b = -0.2485;
 368         float c = 0.543;
 369
 370         _rd_turn_radius_ft = (a * exp(b * fabs(_rudder)) + c) * _sp_turn_radius_ft;
 371
 372         // calculate the angle, alpha, subtended by the arc traversed in time dt
 373         alpha = ((speed * 1.686 * dt) / _rd_turn_radius_ft) * SG_RADIANS_TO_DEGREES;
 374         //cout << _name << " alpha " << alpha << endl;
 375         // make sure that alpha is applied in the right direction
 376         hdg += alpha * sign(_rudder);
 377
 378         SG_NORMALIZE_RANGE(hdg, 0.0, 360.0);
 379
 380         //adjust roll for rudder angle and speed. Another bit of voodoo
 381         raw_roll = _roll_factor * speed * _rudder;
 382     } else {
 383         // _rudder angle is 0
 384         raw_roll = 0;
 385     }
 386
 387     //low pass filter
 388     if (speed < 0)
 389         roll = -roll;
 390
 391     roll = (raw_roll * _roll_constant) + (roll * (1 - _roll_constant));
 392
 393     // adjust target _rudder angle if heading lock engaged
 394     double rudder_diff = 0.0;
 395     if (_hdg_lock) {
 396         double rudder_sense = 0.0;
 397         double diff = fabs(hdg - tgt_heading);
 398         //cout << "_rudder diff" << diff << endl;
 399         if (diff > 180)
 400             diff = fabs(diff - 360);
 401
 402         double sum = hdg + diff;
 403
 404         if (sum > 360.0)
 405             sum -= 360.0;
 406
 407         if (fabs(sum - tgt_heading)< 1.0)
 408             rudder_sense = 1.0;
 409         else
 410             rudder_sense = -1.0;
 411
 412         if (speed < 0)
 413             rudder_sense = -rudder_sense;
 414
 415         if (diff < 15)
 416             _tgt_rudder = diff * rudder_sense;
 417         else
 418             _tgt_rudder = 45 * rudder_sense;
 419
 420         rudder_diff = _tgt_rudder - _rudder;
 421     }
 422
 423     // set the _rudder limit by speed
 424     if (type == "ship" || type == "carrier" || type == "escort"){
 425
 426         if (speed <= 40)
 427             rudder_limit = (-0.825 * speed) + 35;
 428         else
 429             rudder_limit = 2;
 430
 431     } else
 432         rudder_limit = 20;
 433
 434     if (fabs(rudder_diff)> 0.1) { // apply dead zone
 435
 436         if (rudder_diff > 0.0) {
 437             _rudder += _rudder_constant * dt;
 438
 439             if (_rudder > rudder_limit) // apply the _rudder limit
 440                 _rudder = rudder_limit;
 441
 442         } else if (rudder_diff < 0.0) {
 443             _rudder -= _rudder_constant * dt;
 444
 445             if (_rudder < -rudder_limit)
 446                 _rudder = -rudder_limit;
 447
 448         }
 449
 450         // do calculations for radar
 451         UpdateRadar(manager);
 452     }
 453 }//end function
 454
 455 void FGAIShip::AccelTo(double speed) {
 456     tgt_speed = speed;
 457 }
 458
 459 void FGAIShip::PitchTo(double angle) {
 460     tgt_pitch = angle;
 461 }
 462
 463 void FGAIShip::RollTo(double angle) {
 464     tgt_roll = angle;
 465 }
 466
 467 void FGAIShip::YawTo(double angle) {
 468 }
 469
 470 void FGAIShip::ClimbTo(double altitude) {
 471     tgt_altitude_ft = altitude;
 472     _setAltitude(altitude);
 473 }
 474
 475 void FGAIShip::TurnTo(double heading) {
 476     tgt_heading = heading - _lead_angle + _tow_angle;
 477     SG_NORMALIZE_RANGE(tgt_heading, 0.0, 360.0);
 478     _hdg_lock = true;
 479 }
 480
 481 double FGAIShip::sign(double x) {
 482     if (x < 0.0)
 483         return -1.0;
 484     else
 485         return 1.0;
 486 }
 487
 488 void FGAIShip::setFlightPlan(FGAIFlightPlan* f) {
 489     fp = f;
 490 }
 491
 492 void FGAIShip::setName(const string& n) {
 493     _name = n;
 494 }
 495
 496 void FGAIShip::setStartTime(const string& st) {
 497     _start_time = st;
 498 }
 499
 500 void FGAIShip::setUntilTime(const string& ut) {
 501     _until_time = ut;
 502     props->setStringValue("waypoint/wait-until-time", _until_time.c_str());
 503 }
 504
 505 void FGAIShip::setCurrName(const string& c) {
 506     _curr_name = c;
 507     props->setStringValue("waypoint/name-curr", _curr_name.c_str());
 508 }
 509
 510 void FGAIShip::setNextName(const string& n) {
 511     _next_name = n;
 512     props->setStringValue("waypoint/name-next", _next_name.c_str());
 513 }
 514
 515 void FGAIShip::setPrevName(const string& p) {
 516     _prev_name = p;
 517     props->setStringValue("waypoint/name-prev", _prev_name.c_str());
 518 }
 519
 520 void FGAIShip::setRepeat(bool r) {
 521     _repeat = r;
 522 }
 523
 524 void FGAIShip::setRestart(bool r) {
 525     _restart = r;
 526 }
 527
 528 void FGAIShip::setMissed(bool m) {
 529     _missed = m;
 530     props->setBoolValue("waypoint/missed", _missed);
 531 }
 532
 533 void FGAIShip::setRudder(float r) {
 534     _rudder = r;
 535 }
 536
 537 void FGAIShip::setRoll(double rl) {
 538     roll = rl;
 539 }
 540
 541 void FGAIShip::setLeadAngleGain(double g) {
 542     _lead_angle_gain = g;
 543 }
 544
 545 void FGAIShip::setLeadAngleLimit(double l) {
 546     _lead_angle_limit = l;
 547 }
 548
 549 void FGAIShip::setLeadAngleProp(double p) {
 550     _proportion = p;
 551 }
 552
 553 void FGAIShip::setRudderConstant(double rc) {
 554     _rudder_constant = rc;
 555 }
 556
 557 void FGAIShip::setSpeedConstant(double sc) {
 558     _speed_constant = sc;
 559 }
 560
 561 void FGAIShip::setFixedTurnRadius(double ftr) {
 562     _fixed_turn_radius = ftr;
 563 }
 564
 565 void FGAIShip::setInitialTunnel(bool t) {
 566     _initial_tunnel = t;
 567     setTunnel(_initial_tunnel);
 568 }
 569
 570 void FGAIShip::setTunnel(bool t) {
 571     _tunnel = t;
 572 }
 573
 574 void FGAIShip::setWPNames() {
 575
 576     if (prev != 0)
 577         setPrevName(prev->name);
 578     else
 579         setPrevName("");
 580
 581     if (curr != 0)
 582         setCurrName(curr->name);
 583     else{
 584         setCurrName("");
 585         SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: current wp name error" );
 586     }
 587
 588     if (next != 0)
 589         setNextName(next->name);
 590     else
 591         setNextName("");
 592
 593     SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: prev wp name " << prev->name);
 594     SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: current wp name " << curr->name);
 595     SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: next wp name " << next->name);
 596
 597 }
 598
 599 double FGAIShip::getRange(double lat, double lon, double lat2, double lon2) const {
 600
 601     double course, distance, az2;
 602
 603     //calculate the bearing and range of the second pos from the first
 604     geo_inverse_wgs_84(lat, lon, lat2, lon2, &course, &az2, &distance);
 605     distance *= SG_METER_TO_NM;
 606     return distance;
 607 }
 608
 609 double FGAIShip::getCourse(double lat, double lon, double lat2, double lon2) const {
 610
 611     double course, distance, recip;
 612
 613     //calculate the bearing and range of the second pos from the first
 614     geo_inverse_wgs_84(lat, lon, lat2, lon2, &course, &recip, &distance);
 615     if (tgt_speed >= 0) {
 616         return course;
 617         SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: course " << course);
 618     } else {
 619         return recip;
 620         SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: recip " << recip);
 621     }
 622 }
 623
 624 void FGAIShip::ProcessFlightPlan(double dt) {
 625
 626     double time_sec = getDaySeconds();
 627
 628     _dt_count += dt;
 629
 630     ///////////////////////////////////////////////////////////////////////////
 631     // Check Execution time (currently once every 1 sec)
 632     // Add a bit of randomization to prevent the execution of all flight plans
 633     // in synchrony, which can add significant periodic framerate flutter.
 634     ///////////////////////////////////////////////////////////////////////////
 635
 636     //cout << "_start_sec " << _start_sec << " time_sec " << time_sec << endl;
 637     if (_dt_count < _next_run && _start_sec < time_sec)
 638         return;
 639
 640     _next_run = 0.05 + (0.025 * sg_random());
 641
 642     double until_time_sec = 0;
 643     _missed = false;
 644
 645     // check to see if we've reached the point for our next turn
 646     // if the range to the waypoint is less than the calculated turn
 647     // radius we can start the turn to the next leg
 648     _wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
 649     _range_rate = (_wp_range - _old_range) / _dt_count;
 650     double sp_turn_radius_nm = _sp_turn_radius_ft / 6076.1155;
 651     // we need to try to identify a _missed waypoint
 652
 653     // calculate the time needed to turn through an arc of 90 degrees,
 654     // and allow a time error
 655     if (speed != 0)
 656         _missed_time_sec = 10 + ((SGD_PI * sp_turn_radius_nm * 60 * 60) / (2 * fabs(speed)));
 657     else
 658         _missed_time_sec = 10;
 659
 660     _missed_range = 4 * sp_turn_radius_nm;
 661
 662     //cout << _name << " range_rate " << _range_rate << " " << _new_waypoint<< endl ;
 663     //if ((_range_rate > 0) && !_new_waypoint){
 664     if (_range_rate > 0 && _wp_range < _missed_range && !_new_waypoint){
 665         _missed_count += _dt_count;
 666     }
 667
 668     if (_missed_count >= 120)
 669         setMissed(true);
 670     else if (_missed_count >= _missed_time_sec)
 671         setMissed(true);
 672     else
 673         setMissed(false);
 674
 675     _old_range = _wp_range;
 676     setWPNames();
 677
 678     if ((_wp_range < (sp_turn_radius_nm * 1.25)) || _missed || (_waiting && !_new_waypoint)) {
 679
 680         if (_next_name == "TUNNEL"){
 681             _tunnel = !_tunnel;
 682
 683             SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " " << sp_turn_radius_nm );
 684
 685             fp->IncrementWaypoint(false);
 686             next = fp->getNextWaypoint();
 687
 688             if (next->name == "WAITUNTIL" || next->name == "WAIT"
 689                 || next->name == "END" || next->name == "TUNNEL")
 690                 return;
 691
 692             prev = curr;
 693             fp->IncrementWaypoint(false);
 694             curr = fp->getCurrentWaypoint();
 695             next = fp->getNextWaypoint();
 696
 697         }else if(_next_name == "END" || fp->getNextWaypoint() == 0) {
 698
 699             if (_repeat) {
 700                 SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: "<< _name << " Flightplan repeating ");
 701                 fp->restart();
 702                 prev = curr;
 703                 curr = fp->getCurrentWaypoint();
 704                 next = fp->getNextWaypoint();
 705                 setWPNames();
 706                 _wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
 707                 _old_range = _wp_range;
 708                 _range_rate = 0;
 709                 _new_waypoint = true;
 710                 _missed_count = 0;
 711                 _lead_angle = 0;
 712                 AccelTo(prev->speed);
 713             } else if (_restart){
 714                 SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " Flightplan restarting ");
 715                 _missed_count = 0;
 716                 initFlightPlan();
 717             } else {
 718                 SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " Flightplan dying ");
 719                 setDie(true);
 720                 _dt_count = 0;
 721                 return;
 722             }
 723
 724         } else if (_next_name == "WAIT") {
 725
 726             if (_wait_count < next->time_sec) {
 727                 SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: " << _name << " waiting ");
 728                 setSpeed(0);
 729                 _waiting = true;
 730                 _wait_count += _dt_count;
 731                 _dt_count = 0;
 732                 _lead_angle = 0;
 733                 return;
 734             } else {
 735                 SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: " << _name
 736                     << " wait done: getting new waypoints ");
 737                 _waiting = false;
 738                 _wait_count = 0;
 739                 fp->IncrementWaypoint(false);
 740                 next = fp->getNextWaypoint();
 741
 742                 if (next->name == "WAITUNTIL" || next->name == "WAIT"
 743                     || next->name == "END" || next->name == "TUNNEL")
 744                     return;
 745
 746                 prev = curr;
 747                 fp->IncrementWaypoint(false);
 748                 curr = fp->getCurrentWaypoint();
 749                 next = fp->getNextWaypoint();
 750             }
 751
 752         } else if (_next_name == "WAITUNTIL") {
 753             time_sec = getDaySeconds();
 754             until_time_sec = processTimeString(next->time);
 755             _until_time = next->time;
 756             setUntilTime(next->time);
 757             if (until_time_sec > time_sec) {
 758                 SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " "
 759                     << curr->name << " waiting until: "
 760                     << _until_time << " " << until_time_sec << " now " << time_sec );
 761                 setSpeed(0);
 762                 _lead_angle = 0;
 763                 _waiting = true;
 764                 return;
 765             } else {
 766                 SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: "
 767                     << _name << " wait until done: getting new waypoints ");
 768                 setUntilTime("");
 769                 fp->IncrementWaypoint(false);
 770
 771                 while (next->name == "WAITUNTIL") {
 772                     fp->IncrementWaypoint(false);
 773                     next = fp->getNextWaypoint();
 774                 }
 775
 776                 if (next->name == "WAIT")
 777                     return;
 778
 779                 prev = curr;
 780                 fp->IncrementWaypoint(false);
 781                 curr = fp->getCurrentWaypoint();
 782                 next = fp->getNextWaypoint();
 783                 _waiting = false;
 784             }
 785
 786         } else {
 787             //now reorganise the waypoints, so that next becomes current and so on
 788             SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: " << _name << " getting new waypoints ");
 789             fp->IncrementWaypoint(false);
 790             prev = fp->getPreviousWaypoint(); //first waypoint
 791             curr = fp->getCurrentWaypoint();  //second waypoint
 792             next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 793         }
 794
 795         setWPNames();
 796         _new_waypoint = true;
 797         _missed_count = 0;
 798         _range_rate = 0;
 799         _lead_angle = 0;
 800         _wp_range = getRange(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
 801         _old_range = _wp_range;
 802         setWPPos();
 803         object_type type = getType();
 804
 805         if (type != 10)
 806             AccelTo(prev->speed);
 807
 808         _curr_alt = curr->altitude;
 809         _prev_alt = prev->altitude;
 810
 811     } else {
 812         _new_waypoint = false;
 813     }
 814
 815     //   now revise the required course for the next way point
 816     _course = getCourse(pos.getLatitudeDeg(), pos.getLongitudeDeg(), curr->latitude, curr->longitude);
 817
 818     if (finite(_course))
 819         TurnTo(_course);
 820     else
 821         SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: Bearing or Range is not a finite number");
 822
 823     _dt_count = 0;
 824 } // end Processing FlightPlan
 825
 826 bool FGAIShip::initFlightPlan() {
 827
 828     SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " initializing waypoints ");
 829
 830     bool init = false;
 831     _start_sec = 0;
 832     _tunnel = _initial_tunnel;
 833
 834     fp->restart();
 835     fp->IncrementWaypoint(false);
 836
 837     prev = fp->getPreviousWaypoint(); //first waypoint
 838     curr = fp->getCurrentWaypoint();  //second waypoint
 839     next = fp->getNextWaypoint();     //third waypoint (might not exist!)
 840
 841     while (curr->name == "WAIT" || curr->name == "WAITUNTIL") {  // don't wait when initialising
 842         SG_LOG(SG_GENERAL, SG_DEBUG, "AIShip: " << _name << " re-initializing waypoints ");
 843         fp->IncrementWaypoint(false);
 844         curr = fp->getCurrentWaypoint();
 845         next = fp->getNextWaypoint();
 846     } // end while loop
 847
 848     if (!_start_time.empty()){
 849         _start_sec = processTimeString(_start_time);
 850         double day_sec = getDaySeconds();
 851
 852         if (_start_sec < day_sec){
 853             //cout << "flight plan has already started " << _start_time << endl;
 854             init = advanceFlightPlan(_start_sec, day_sec);
 855
 856         } else if (_start_sec > day_sec && _repeat) {
 857             //cout << "flight plan has not started, " << _start_time;
 858             //cout << "offsetting start time by -24 hrs" << endl;
 859             _start_sec -= _day;
 860             init = advanceFlightPlan(_start_sec, day_sec);
 861         }
 862
 863         if (init)
 864             _start_sec = 0; // set to zero for an immediate start of the Flight Plan
 865         else {
 866             fp->restart();
 867             fp->IncrementWaypoint(false);
 868             prev = fp->getPreviousWaypoint();
 869             curr = fp->getCurrentWaypoint();
 870             next = fp->getNextWaypoint();
 871             return false;
 872         }
 873
 874     } else {
 875         setLatitude(prev->latitude);
 876         setLongitude(prev->longitude);
 877         setSpeed(prev->speed);
 878     }
 879
 880     setWPNames();
 881     setHeading(getCourse(prev->latitude, prev->longitude, curr->latitude, curr->longitude));
 882     _wp_range = getRange(prev->latitude, prev->longitude, curr->latitude, curr->longitude);
 883     _old_range = _wp_range;
 884     _range_rate = 0;
 885     _hdg_lock = true;
 886     _missed = false;
 887     _missed_count = 0;
 888     _new_waypoint = true;
 889
 890     SG_LOG(SG_GENERAL, SG_ALERT, "AIShip: " << _name << " done initialising waypoints " << _tunnel);
 891     if (prev)
 892         init = true;
 893
 894     if (init)
 895         return true;
 896     else
 897         return false;
 898
 899 } // end of initialization
 900
 901
 902 double FGAIShip::processTimeString(const string& theTime) {
 903
 904     int Hour;
 905     int Minute;
 906     int Second;
 907
 908     // first split theTime string into
 909     //  hour, minute, second and convert to int;
 910     Hour   = atoi(theTime.substr(0,2).c_str());
 911     Minute = atoi(theTime.substr(3,5).c_str());
 912     Second = atoi(theTime.substr(6,8).c_str());
 913
 914     // offset by a day-sec to allow for starting a day earlier
 915     double time_seconds = Hour * 3600
 916         + Minute * 60
 917         + Second;
 918
 919     return time_seconds;
 920 }
 921
 922 double FGAIShip::getDaySeconds () {
 923     // Date and time
 924     struct tm *t = globals->get_time_params()->getGmt();
 925
 926     double day_seconds = t->tm_hour * 3600
 927         + t->tm_min * 60
 928         + t->tm_sec;
 929
 930     return day_seconds;
 931 }
 932
 933 bool FGAIShip::advanceFlightPlan (double start_sec, double day_sec) {
 934
 935     double elapsed_sec = start_sec;
 936     double distance_nm = 0;
 937
 938     //cout << "advancing flight plan start_sec: " << start_sec << " " << day_sec << endl;
 939
 940     while ( elapsed_sec < day_sec ) {
 941
 942         if (next->name == "END" || fp->getNextWaypoint() == 0) {
 943
 944             if (_repeat ) {
 945                 //cout << _name << ": " << "restarting flightplan" << endl;
 946                 fp->restart();
 947                 curr = fp->getCurrentWaypoint();
 948                 next = fp->getNextWaypoint();
 949             } else {
 950                 //cout << _name << ": " << "ending flightplan" << endl;
 951                 setDie(true);
 952                 return false;
 953             }
 954
 955         } else if (next->name == "WAIT") {
 956             //cout << _name << ": begin WAIT: " << prev->name << " ";
 957             //cout << curr->name << " " << next->name << endl;
 958
 959             elapsed_sec += next->time_sec;
 960
 961             if ( elapsed_sec >= day_sec)
 962                 continue;
 963
 964             fp->IncrementWaypoint(false);
 965             next = fp->getNextWaypoint();
 966
 967             if (next->name != "WAITUNTIL" && next->name != "WAIT"
 968                 && next->name != "END") {
 969                     prev = curr;
 970                     fp->IncrementWaypoint(false);
 971                     curr = fp->getCurrentWaypoint();
 972                     next = fp->getNextWaypoint();
 973             }
 974
 975         } else if (next->name == "WAITUNTIL") {
 976             double until_sec = processTimeString(next->time);
 977
 978             if (until_sec > _start_sec && start_sec < 0)
 979                 until_sec -= _day;
 980
 981             if (elapsed_sec < until_sec)
 982                 elapsed_sec = until_sec;
 983
 984             if (elapsed_sec >= day_sec )
 985                 break;
 986
 987             fp->IncrementWaypoint(false);
 988             next = fp->getNextWaypoint();
 989
 990             if (next->name != "WAITUNTIL" && next->name != "WAIT") {
 991                 prev = curr;
 992                 fp->IncrementWaypoint(false);
 993                 curr = fp->getCurrentWaypoint();
 994                 next = fp->getNextWaypoint();
 995             }
 996
 997             //cout << _name << ": end WAITUNTIL: ";
 998             //cout << prev->name << " " << curr->name << " " << next->name <<  endl;
 999
1000         } else {
1001             distance_nm = getRange(prev->latitude, prev->longitude, curr->latitude, curr->longitude);
1002             elapsed_sec += distance_nm * 60 * 60 / prev->speed;
1003
1004             if (elapsed_sec >= day_sec)
1005                 continue;
1006
1007             fp->IncrementWaypoint(false);
1008             prev = fp->getPreviousWaypoint();
1009             curr = fp->getCurrentWaypoint();
1010             next = fp->getNextWaypoint();
1011         }
1012
1013     }   // end while
1014
1015     // the required position lies between the previous and current waypoints
1016     // so we will calculate the distance back up the track from the current waypoint
1017     // then calculate the lat and lon.
1018
1019     //cout << "advancing flight plan done elapsed_sec: " << elapsed_sec
1020     //    << " " << day_sec << endl;
1021
1022     double time_diff = elapsed_sec - day_sec;
1023     double lat, lon, recip;
1024
1025     //cout << " time diff " << time_diff << endl;
1026
1027     if (next->name == "WAIT" ){
1028         setSpeed(0);
1029         lat = curr->latitude;
1030         lon = curr->longitude;
1031         _wait_count= time_diff;
1032         _waiting = true;
1033     } else if (next->name == "WAITUNTIL") {
1034         setSpeed(0);
1035         lat = curr->latitude;
1036         lon = curr->longitude;
1037         _waiting = true;
1038     } else {
1039         setSpeed(prev->speed);
1040         distance_nm = speed * time_diff / (60 * 60);
1041         double brg = getCourse(curr->latitude, curr->longitude, prev->latitude, prev->longitude);
1042
1043         //cout << " brg " << brg << " from " << curr->name << " to " << prev->name << " "
1044         //    << " lat "  << curr->latitude << " lon " << curr->longitude
1045         //    << " distance m " << distance_nm * SG_NM_TO_METER << endl;
1046
1047         lat = geo_direct_wgs_84 (curr->latitude, curr->longitude, brg,
1048             distance_nm * SG_NM_TO_METER, &lat, &lon, &recip );
1049         lon = geo_direct_wgs_84 (curr->latitude, curr->longitude, brg,
1050             distance_nm * SG_NM_TO_METER, &lat, &lon, &recip );
1051         recip = geo_direct_wgs_84 (curr->latitude, curr->longitude, brg,
1052             distance_nm * SG_NM_TO_METER, &lat, &lon, &recip );
1053     }
1054
1055     setLatitude(lat);
1056     setLongitude(lon);
1057
1058     return true;
1059 }
1060
1061 void FGAIShip::setWPPos() {
1062
1063     if (curr->name == "END" || curr->name == "WAIT"
1064         || curr->name == "WAITUNTIL" || curr->name == "TUNNEL"){
1065             //cout << curr->name << " returning" << endl;
1066             return;
1067     }
1068
1069     double elevation_m = 0;
1070     wppos.setLatitudeDeg(curr->latitude);
1071     wppos.setLongitudeDeg(curr->longitude);
1072     wppos.setElevationM(0);
1073
1074     if (curr->on_ground){
1075
1076         if (globals->get_scenery()->get_elevation_m(SGGeod::fromGeodM(wppos, 3000),
1077             elevation_m, &_material, 0)){
1078                 wppos.setElevationM(elevation_m);
1079         }
1080
1081         //cout << curr->name << " setting measured  elev " << elevation_m << endl;
1082
1083     } else {
1084         wppos.setElevationM(curr->altitude);
1085         //cout << curr->name << " setting FP elev " << elevation_m << endl;
1086     }
1087
1088     curr->altitude = wppos.getElevationM();
1089
1090 }
1091
1092 void FGAIShip::setXTrackError() {
1093
1094     double course = getCourse(prev->latitude, prev->longitude,
1095         curr->latitude, curr->longitude);
1096     double brg = getCourse(pos.getLatitudeDeg(), pos.getLongitudeDeg(),
1097         curr->latitude, curr->longitude);
1098     double xtrack_error_nm = sin((course - brg)* SG_DEGREES_TO_RADIANS) * _wp_range;
1099     double factor = -0.0045 * speed + 1;
1100     double limit = _lead_angle_limit * factor;
1101
1102     if (_wp_range > 0){
1103         _lead_angle = atan2(xtrack_error_nm,(_wp_range * _proportion)) * SG_RADIANS_TO_DEGREES;
1104     } else
1105         _lead_angle = 0;
1106
1107     _lead_angle *= _lead_angle_gain * factor;
1108     _xtrack_error = xtrack_error_nm * 6076.1155;
1109
1110     SG_CLAMP_RANGE(_lead_angle, -limit, limit);
1111
1112 }