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