src/FDM/flight.cxx

   1 // flight.cxx -- a general interface to the various flight models
   2 //
   3 // Written by Curtis Olson, started May 1997.
   4 //
   5 // Copyright (C) 1997  Curtis L. Olson  - http://www.flightgear.org/~curt
   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 // $Id$
  22
  23 #ifdef HAVE_CONFIG_H
  24 #  include "config.h"
  25 #endif
  26
  27 #include "flight.hxx"
  28
  29 #include <simgear/constants.h>
  30 #include <simgear/debug/logstream.hxx>
  31 #include <simgear/math/SGMath.hxx>
  32 #include <simgear/timing/timestamp.hxx>
  33
  34 #include <Scenery/scenery.hxx>
  35 #include <Main/globals.hxx>
  36 #include <Main/fg_props.hxx>
  37 #include <FDM/groundcache.hxx>
  38
  39
  40 static inline void assign(double* ptr, const SGVec3d& vec)
  41 {
  42   ptr[0] = vec[0];
  43   ptr[1] = vec[1];
  44   ptr[2] = vec[2];
  45 }
  46
  47 // Constructor
  48 FGInterface::FGInterface()
  49 {
  50     _setup();
  51 }
  52
  53 FGInterface::FGInterface( double dt )
  54 {
  55     _setup();
  56 }
  57
  58 // Destructor
  59 FGInterface::~FGInterface() {
  60     // unbind();                   // FIXME: should be called explicitly
  61 }
  62
  63 int
  64 FGInterface::_calc_multiloop (double dt)
  65 {
  66   // Since some time the simulation time increments we get here are
  67   // already a multiple of the basic update freqency.
  68   // So, there is no need to do our own multiloop rounding with all bad
  69   // roundoff problems when we already have nearly accurate values.
  70   // Only the speedup thing must be still handled here
  71   int hz = fgGetInt("/sim/model-hz");
  72   int multiloop = SGMiscd::roundToInt(dt*hz);
  73   int speedup = fgGetInt("/sim/speed-up");
  74   return multiloop * speedup;
  75 }
  76
  77
  78 /**
  79  * Set default values for the state of the FDM.
  80  *
  81  * This method is invoked by the constructors.
  82  */
  83 void
  84 FGInterface::_setup ()
  85 {
  86     inited = false;
  87     bound = false;
  88
  89     d_cg_rp_body_v = SGVec3d::zeros();
  90     v_dot_local_v = SGVec3d::zeros();
  91     v_dot_body_v = SGVec3d::zeros();
  92     a_cg_body_v = SGVec3d::zeros();
  93     a_pilot_body_v = SGVec3d::zeros();
  94     n_cg_body_v = SGVec3d::zeros();
  95     v_local_v = SGVec3d::zeros();
  96     v_local_rel_ground_v = SGVec3d::zeros();
  97     v_local_airmass_v = SGVec3d::zeros();
  98     v_wind_body_v = SGVec3d::zeros();
  99     omega_body_v = SGVec3d::zeros();
 100     euler_rates_v = SGVec3d::zeros();
 101     geocentric_rates_v = SGVec3d::zeros();
 102     geodetic_position_v = SGGeod::fromRadM(0, 0, 0);
 103     cartesian_position_v = SGVec3d::fromGeod(geodetic_position_v);
 104     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 105     euler_angles_v = SGVec3d::zeros();
 106
 107     nlf=0;
 108     v_rel_wind=v_true_kts=0;
 109     v_ground_speed=v_equiv_kts=0;
 110     v_calibrated_kts=0;
 111     alpha=beta=0;
 112     gamma_vert_rad=0;
 113     density=mach_number=0;
 114     static_pressure=total_pressure=0;
 115     dynamic_pressure=0;
 116     static_temperature=total_temperature=0;
 117     sea_level_radius=earth_position_angle=0;
 118     runway_altitude=0;
 119     climb_rate=0;
 120     altitude_agl=0;
 121     track=0;
 122 }
 123
 124 void
 125 FGInterface::init () {}
 126
 127 /**
 128  * Initialize the state of the FDM.
 129  *
 130  * Subclasses of FGInterface may do their own, additional initialization,
 131  * but there is some that is common to all.  Normally, they should call
 132  * this before they begin their own init to make sure the basic structures
 133  * are set up properly.
 134  */
 135 void
 136 FGInterface::common_init ()
 137 {
 138     SG_LOG( SG_FLIGHT, SG_INFO, "Start common FDM init" );
 139
 140     set_inited( true );
 141
 142     ground_cache.set_cache_time_offset(globals->get_sim_time_sec());
 143
 144     // Set initial position
 145     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing position..." );
 146     double lon = fgGetDouble("/sim/presets/longitude-deg")
 147       * SGD_DEGREES_TO_RADIANS;
 148     double lat = fgGetDouble("/sim/presets/latitude-deg")
 149       * SGD_DEGREES_TO_RADIANS;
 150     double alt_ft = fgGetDouble("/sim/presets/altitude-ft");
 151     double alt_m = alt_ft * SG_FEET_TO_METER;
 152     set_Longitude( lon );
 153     set_Latitude( lat );
 154     SG_LOG( SG_FLIGHT, SG_INFO, "Checking for lon = "
 155             << lon*SGD_RADIANS_TO_DEGREES << "deg, lat = "
 156             << lat*SGD_RADIANS_TO_DEGREES << "deg, alt = "
 157             << alt_ft << "ft");
 158
 159     double ground_elev_m = get_groundlevel_m(lat, lon, alt_m);
 160     double ground_elev_ft = ground_elev_m * SG_METER_TO_FEET;
 161     _set_Runway_altitude ( ground_elev_ft );
 162     if ( fgGetBool("/sim/presets/onground") || alt_ft < ground_elev_ft ) {
 163         fgSetDouble("/position/altitude-ft", ground_elev_ft + 0.1);
 164         set_Altitude( ground_elev_ft + 0.1);
 165     } else {
 166         set_Altitude( alt_ft );
 167     }
 168
 169     // Set ground elevation
 170     SG_LOG( SG_FLIGHT, SG_INFO,
 171             "...initializing ground elevation to " << ground_elev_ft
 172             << "ft..." );
 173
 174     // Set sea-level radius
 175     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing sea-level radius..." );
 176     SG_LOG( SG_FLIGHT, SG_INFO, " lat = "
 177             << fgGetDouble("/sim/presets/latitude-deg")
 178             << " alt = " << get_Altitude() );
 179     double slr = SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v);
 180     _set_Sea_level_radius( slr * SG_METER_TO_FEET );
 181
 182     // Set initial velocities
 183     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing velocities..." );
 184     if ( !fgHasNode("/sim/presets/speed-set") ) {
 185         set_V_calibrated_kts(0.0);
 186     } else {
 187         const string speedset = fgGetString("/sim/presets/speed-set");
 188         if ( speedset == "knots" || speedset == "KNOTS" ) {
 189             set_V_calibrated_kts( fgGetDouble("/sim/presets/airspeed-kt") );
 190         } else if ( speedset == "mach" || speedset == "MACH" ) {
 191             set_Mach_number( fgGetDouble("/sim/presets/mach") );
 192         } else if ( speedset == "UVW" || speedset == "uvw" ) {
 193             set_Velocities_Wind_Body(
 194                                      fgGetDouble("/sim/presets/uBody-fps"),
 195                                      fgGetDouble("/sim/presets/vBody-fps"),
 196                                      fgGetDouble("/sim/presets/wBody-fps") );
 197         } else if ( speedset == "NED" || speedset == "ned" ) {
 198             set_Velocities_Local(
 199                                  fgGetDouble("/sim/presets/speed-north-fps"),
 200                                  fgGetDouble("/sim/presets/speed-east-fps"),
 201                                  fgGetDouble("/sim/presets/speed-down-fps") );
 202         } else {
 203             SG_LOG( SG_FLIGHT, SG_ALERT,
 204                     "Unrecognized value for /sim/presets/speed-set: "
 205                     << speedset);
 206             set_V_calibrated_kts( 0.0 );
 207         }
 208     }
 209
 210     // Set initial Euler angles
 211     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing Euler angles..." );
 212     set_Euler_Angles( fgGetDouble("/sim/presets/roll-deg")
 213                         * SGD_DEGREES_TO_RADIANS,
 214                       fgGetDouble("/sim/presets/pitch-deg")
 215                         * SGD_DEGREES_TO_RADIANS,
 216                       fgGetDouble("/sim/presets/heading-deg")
 217                         * SGD_DEGREES_TO_RADIANS );
 218
 219     SG_LOG( SG_FLIGHT, SG_INFO, "End common FDM init" );
 220 }
 221
 222
 223 /**
 224  * Bind getters and setters to properties.
 225  *
 226  * The bind() method will be invoked after init().  Note that unlike
 227  * the usual implementations of FGSubsystem::bind(), this method does
 228  * not automatically pick up existing values for the properties at
 229  * bind time; instead, all values are set explicitly in the init()
 230  * method.
 231  */
 232 void
 233 FGInterface::bind ()
 234 {
 235   bound = true;
 236
 237                         // Aircraft position
 238   fgTie("/position/latitude-deg", this,
 239         &FGInterface::get_Latitude_deg,
 240         &FGInterface::set_Latitude_deg,
 241         false);
 242   fgSetArchivable("/position/latitude-deg");
 243   fgTie("/position/longitude-deg", this,
 244         &FGInterface::get_Longitude_deg,
 245         &FGInterface::set_Longitude_deg,
 246         false);
 247   fgSetArchivable("/position/longitude-deg");
 248   fgTie("/position/altitude-ft", this,
 249         &FGInterface::get_Altitude,
 250         &FGInterface::set_Altitude,
 251         false);
 252   fgSetArchivable("/position/altitude-ft");
 253   fgTie("/position/altitude-agl-ft", this,
 254         &FGInterface::get_Altitude_AGL, &FGInterface::set_AltitudeAGL);
 255   fgSetArchivable("/position/ground-elev-ft");
 256   fgTie("/position/ground-elev-ft", this,
 257         &FGInterface::get_Runway_altitude); // read-only
 258   fgSetArchivable("/position/ground-elev-m");
 259   fgTie("/position/ground-elev-m", this,
 260         &FGInterface::get_Runway_altitude_m); // read-only
 261   fgTie("/environment/ground-elevation-m", this,
 262         &FGInterface::get_Runway_altitude_m); // read-only
 263   fgSetArchivable("/position/sea-level-radius-ft");
 264   fgTie("/position/sea-level-radius-ft", this,
 265         &FGInterface::get_Sea_level_radius,
 266         &FGInterface::_set_Sea_level_radius);
 267
 268                                 // Orientation
 269   fgTie("/orientation/roll-deg", this,
 270         &FGInterface::get_Phi_deg,
 271         &FGInterface::set_Phi_deg);
 272   fgSetArchivable("/orientation/roll-deg");
 273   fgTie("/orientation/pitch-deg", this,
 274         &FGInterface::get_Theta_deg,
 275         &FGInterface::set_Theta_deg);
 276   fgSetArchivable("/orientation/pitch-deg");
 277   fgTie("/orientation/heading-deg", this,
 278         &FGInterface::get_Psi_deg,
 279         &FGInterface::set_Psi_deg);
 280   fgSetArchivable("/orientation/heading-deg");
 281   fgTie("/orientation/track-deg", this,
 282         &FGInterface::get_Track);
 283
 284   // Body-axis "euler rates" (rotation speed, but in a funny
 285   // representation).
 286   fgTie("/orientation/roll-rate-degps", this,
 287         &FGInterface::get_Phi_dot_degps, &FGInterface::set_Phi_dot_degps);
 288   fgTie("/orientation/pitch-rate-degps", this,
 289         &FGInterface::get_Theta_dot_degps, &FGInterface::set_Theta_dot_degps);
 290   fgTie("/orientation/yaw-rate-degps", this,
 291         &FGInterface::get_Psi_dot_degps, &FGInterface::set_Psi_dot_degps);
 292
 293   fgTie("/orientation/p-body", this, &FGInterface::get_P_body);
 294   fgTie("/orientation/q-body", this, &FGInterface::get_Q_body);
 295   fgTie("/orientation/r-body", this, &FGInterface::get_R_body);
 296
 297                                 // Ground speed knots
 298   fgTie("/velocities/groundspeed-kt", this,
 299         &FGInterface::get_V_ground_speed_kt);
 300
 301                                 // Calibrated airspeed
 302   fgTie("/velocities/airspeed-kt", this,
 303         &FGInterface::get_V_calibrated_kts,
 304         &FGInterface::set_V_calibrated_kts,
 305         false);
 306
 307     fgTie("/velocities/equivalent-kt", this,
 308         &FGInterface::get_V_equiv_kts);
 309
 310                                 // Mach number
 311   fgTie("/velocities/mach", this,
 312         &FGInterface::get_Mach_number,
 313         &FGInterface::set_Mach_number,
 314         false);
 315
 316                                 // Local velocities
 317 //   fgTie("/velocities/speed-north-fps", this,
 318 //      &FGInterface::get_V_north,
 319 //      &FGInterface::set_V_north);
 320 //   fgSetArchivable("/velocities/speed-north-fps");
 321 //   fgTie("/velocities/speed-east-fps", this,
 322 //      &FGInterface::get_V_east,
 323 //      &FGInterface::set_V_east);
 324 //   fgSetArchivable("/velocities/speed-east-fps");
 325 //   fgTie("/velocities/speed-down-fps", this,
 326 //      &FGInterface::get_V_down,
 327 //      &FGInterface::set_V_down);
 328 //   fgSetArchivable("/velocities/speed-down-fps");
 329                                 // FIXME: Temporarily read-only, until the
 330                                 // incompatibilities between JSBSim and
 331                                 // LaRCSim are fixed (LaRCSim adds the
 332                                 // earth's rotation to the east velocity).
 333   fgTie("/velocities/speed-north-fps", this,
 334         &FGInterface::get_V_north, &FGInterface::set_V_north);
 335   fgTie("/velocities/speed-east-fps", this,
 336         &FGInterface::get_V_east, &FGInterface::set_V_east);
 337   fgTie("/velocities/speed-down-fps", this,
 338         &FGInterface::get_V_down, &FGInterface::set_V_down);
 339
 340   fgTie("/velocities/north-relground-fps", this,
 341     &FGInterface::get_V_north_rel_ground);
 342   fgTie("/velocities/east-relground-fps", this,
 343     &FGInterface::get_V_east_rel_ground);
 344   fgTie("/velocities/down-relground-fps", this,
 345     &FGInterface::get_V_down_rel_ground);
 346
 347
 348                                 // Relative wind
 349                                 // FIXME: temporarily archivable, until
 350                                 // the NED problem is fixed.
 351   fgTie("/velocities/uBody-fps", this,
 352         &FGInterface::get_uBody,
 353         &FGInterface::set_uBody,
 354         false);
 355   fgSetArchivable("/velocities/uBody-fps");
 356   fgTie("/velocities/vBody-fps", this,
 357         &FGInterface::get_vBody,
 358         &FGInterface::set_vBody,
 359         false);
 360   fgSetArchivable("/velocities/vBody-fps");
 361   fgTie("/velocities/wBody-fps", this,
 362         &FGInterface::get_wBody,
 363         &FGInterface::set_wBody,
 364         false);
 365   fgSetArchivable("/velocities/wBody-fps");
 366
 367                                 // Climb and slip (read-only)
 368   fgTie("/velocities/vertical-speed-fps", this,
 369         &FGInterface::get_Climb_Rate,
 370   &FGInterface::set_Climb_Rate );
 371   fgTie("/velocities/glideslope", this,
 372   &FGInterface::get_Gamma_vert_rad,
 373   &FGInterface::set_Gamma_vert_rad );
 374   fgTie("/orientation/side-slip-rad", this,
 375         &FGInterface::get_Beta, &FGInterface::_set_Beta);
 376   fgTie("/orientation/side-slip-deg", this,
 377   &FGInterface::get_Beta_deg); // read-only
 378   fgTie("/orientation/alpha-deg", this,
 379   &FGInterface::get_Alpha_deg, &FGInterface::set_Alpha_deg); // read-only
 380   fgTie("/accelerations/nlf", this,
 381   &FGInterface::get_Nlf); // read-only
 382
 383                                 // NED accelerations
 384   fgTie("/accelerations/ned/north-accel-fps_sec",
 385         this, &FGInterface::get_V_dot_north);
 386   fgTie("/accelerations/ned/east-accel-fps_sec",
 387         this, &FGInterface::get_V_dot_east);
 388   fgTie("/accelerations/ned/down-accel-fps_sec",
 389         this, &FGInterface::get_V_dot_down);
 390
 391                                 // Pilot accelerations
 392   fgTie("/accelerations/pilot/x-accel-fps_sec",
 393         this, &FGInterface::get_A_X_pilot, &FGInterface::set_A_X_pilot);
 394   fgTie("/accelerations/pilot/y-accel-fps_sec",
 395         this, &FGInterface::get_A_Y_pilot, &FGInterface::set_A_Y_pilot);
 396   fgTie("/accelerations/pilot/z-accel-fps_sec",
 397         this, &FGInterface::get_A_Z_pilot, &FGInterface::set_A_Z_pilot);
 398
 399   fgTie("/accelerations/n-z-cg-fps_sec", this, &FGInterface::get_N_Z_cg);
 400
 401 }
 402
 403
 404 /**
 405  * Unbind any properties bound to this FDM.
 406  *
 407  * This method allows the FDM to release properties so that a new
 408  * FDM can bind them instead.
 409  */
 410 void
 411 FGInterface::unbind ()
 412 {
 413   if (!bound) {
 414     return;
 415   }
 416
 417   bound = false;
 418
 419   fgUntie("/position/latitude-deg");
 420   fgUntie("/position/longitude-deg");
 421   fgUntie("/position/altitude-ft");
 422   fgUntie("/position/altitude-agl-ft");
 423   fgUntie("/position/ground-elev-ft");
 424   fgUntie("/position/ground-elev-m");
 425   fgUntie("/environment/ground-elevation-m");
 426   fgUntie("/position/sea-level-radius-ft");
 427   fgUntie("/orientation/roll-deg");
 428   fgUntie("/orientation/pitch-deg");
 429   fgUntie("/orientation/heading-deg");
 430   fgUntie("/orientation/track-deg");
 431   fgUntie("/orientation/roll-rate-degps");
 432   fgUntie("/orientation/pitch-rate-degps");
 433   fgUntie("/orientation/yaw-rate-degps");
 434   fgUntie("/orientation/p-body");
 435   fgUntie("/orientation/q-body");
 436   fgUntie("/orientation/r-body");
 437   fgUntie("/orientation/side-slip-rad");
 438   fgUntie("/orientation/side-slip-deg");
 439   fgUntie("/orientation/alpha-deg");
 440   fgUntie("/velocities/airspeed-kt");
 441   fgUntie("/velocities/groundspeed-kt");
 442   fgUntie("/velocities/equivalent-kt");
 443   fgUntie("/velocities/mach");
 444   fgUntie("/velocities/speed-north-fps");
 445   fgUntie("/velocities/speed-east-fps");
 446   fgUntie("/velocities/speed-down-fps");
 447   fgUntie("/velocities/north-relground-fps");
 448   fgUntie("/velocities/east-relground-fps");
 449   fgUntie("/velocities/down-relground-fps");
 450   fgUntie("/velocities/uBody-fps");
 451   fgUntie("/velocities/vBody-fps");
 452   fgUntie("/velocities/wBody-fps");
 453   fgUntie("/velocities/vertical-speed-fps");
 454   fgUntie("/velocities/glideslope");
 455   fgUntie("/accelerations/nlf");
 456   fgUntie("/accelerations/pilot/x-accel-fps_sec");
 457   fgUntie("/accelerations/pilot/y-accel-fps_sec");
 458   fgUntie("/accelerations/pilot/z-accel-fps_sec");
 459   fgUntie("/accelerations/ned/north-accel-fps_sec");
 460   fgUntie("/accelerations/ned/east-accel-fps_sec");
 461   fgUntie("/accelerations/ned/down-accel-fps_sec");
 462   fgUntie("/accelerations/n-z-cg-fps_sec");
 463 }
 464
 465 /**
 466  * Update the state of the FDM (i.e. run the equations of motion).
 467  */
 468 void
 469 FGInterface::update (double dt)
 470 {
 471     SG_LOG(SG_FLIGHT, SG_ALERT, "dummy update() ... SHOULDN'T BE CALLED!");
 472 }
 473
 474
 475 void FGInterface::_updatePositionM(const SGVec3d& cartPos)
 476 {
 477     TrackComputer tracker( track, geodetic_position_v );
 478     cartesian_position_v = cartPos;
 479     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 480     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 481     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 482     _update_ground_elev_at_pos();
 483 }
 484
 485
 486 void FGInterface::_updatePosition(const SGGeod& geod)
 487 {
 488     TrackComputer tracker( track, geodetic_position_v );
 489     geodetic_position_v = geod;
 490     cartesian_position_v = SGVec3d::fromGeod(geodetic_position_v);
 491     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 492
 493     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 494     _update_ground_elev_at_pos();
 495 }
 496
 497
 498 void FGInterface::_updatePosition(const SGGeoc& geoc)
 499 {
 500     TrackComputer tracker( track, geodetic_position_v );
 501     geocentric_position_v = geoc;
 502     cartesian_position_v = SGVec3d::fromGeoc(geocentric_position_v);
 503     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 504
 505     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 506     _update_ground_elev_at_pos();
 507 }
 508
 509
 510 void FGInterface::_updateGeodeticPosition( double lat, double lon, double alt )
 511 {
 512     _updatePosition(SGGeod::fromRadFt(lon, lat, alt));
 513 }
 514
 515
 516 void FGInterface::_updateGeocentricPosition( double lat, double lon,
 517                                              double alt )
 518 {
 519     _updatePosition(SGGeoc::fromRadFt(lon, lat, get_Sea_level_radius() + alt));
 520 }
 521
 522 void FGInterface::_update_ground_elev_at_pos( void ) {
 523     double groundlevel_m = get_groundlevel_m(geodetic_position_v);
 524     _set_Runway_altitude( groundlevel_m * SG_METER_TO_FEET );
 525 }
 526
 527 // Positions
 528 void FGInterface::set_Latitude(double lat) {
 529     geodetic_position_v.setLatitudeRad(lat);
 530 }
 531
 532 void FGInterface::set_Longitude(double lon) {
 533     geodetic_position_v.setLongitudeRad(lon);
 534 }
 535
 536 void FGInterface::set_Altitude(double alt) {
 537     geodetic_position_v.setElevationFt(alt);
 538 }
 539
 540 void FGInterface::set_AltitudeAGL(double altagl) {
 541     altitude_agl=altagl;
 542 }
 543
 544 // Velocities
 545 void FGInterface::set_V_calibrated_kts(double vc) {
 546     v_calibrated_kts = vc;
 547 }
 548
 549 void FGInterface::set_Mach_number(double mach) {
 550     mach_number = mach;
 551 }
 552
 553 void FGInterface::set_Velocities_Local( double north,
 554                                         double east,
 555                                         double down ){
 556     v_local_v[0] = north;
 557     v_local_v[1] = east;
 558     v_local_v[2] = down;
 559 }
 560
 561 void FGInterface::set_Velocities_Wind_Body( double u,
 562                                             double v,
 563                                             double w){
 564     v_wind_body_v[0] = u;
 565     v_wind_body_v[1] = v;
 566     v_wind_body_v[2] = w;
 567 }
 568
 569 // Euler angles
 570 void FGInterface::set_Euler_Angles( double phi,
 571                                     double theta,
 572                                     double psi ) {
 573     euler_angles_v[0] = phi;
 574     euler_angles_v[1] = theta;
 575     euler_angles_v[2] = psi;
 576 }
 577
 578 // Flight Path
 579 void FGInterface::set_Climb_Rate( double roc) {
 580     climb_rate = roc;
 581 }
 582
 583 void FGInterface::set_Gamma_vert_rad( double gamma) {
 584     gamma_vert_rad = gamma;
 585 }
 586
 587 void FGInterface::set_Static_pressure(double p) { static_pressure = p; }
 588 void FGInterface::set_Static_temperature(double T) { static_temperature = T; }
 589 void FGInterface::set_Density(double rho) { density = rho; }
 590
 591 void FGInterface::set_Velocities_Local_Airmass (double wnorth,
 592                                                 double weast,
 593                                                 double wdown ) {
 594     v_local_airmass_v[0] = wnorth;
 595     v_local_airmass_v[1] = weast;
 596     v_local_airmass_v[2] = wdown;
 597 }
 598
 599
 600 void FGInterface::_busdump(void) {
 601
 602     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rp_body_v: " << d_cg_rp_body_v);
 603     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_local_v: " << v_dot_local_v);
 604     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_body_v: " << v_dot_body_v);
 605     SG_LOG(SG_FLIGHT,SG_INFO,"a_cg_body_v: " << a_cg_body_v);
 606     SG_LOG(SG_FLIGHT,SG_INFO,"a_pilot_body_v: " << a_pilot_body_v);
 607     SG_LOG(SG_FLIGHT,SG_INFO,"n_cg_body_v: " << n_cg_body_v);
 608     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_v: " << v_local_v);
 609     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_ground_v: " << v_local_rel_ground_v);
 610     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_airmass_v: " << v_local_airmass_v);
 611     SG_LOG(SG_FLIGHT,SG_INFO,"v_wind_body_v: " << v_wind_body_v);
 612     SG_LOG(SG_FLIGHT,SG_INFO,"omega_body_v: " << omega_body_v);
 613     SG_LOG(SG_FLIGHT,SG_INFO,"euler_rates_v: " << euler_rates_v);
 614     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_rates_v: " << geocentric_rates_v);
 615     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_position_v: " << geocentric_position_v);
 616     SG_LOG(SG_FLIGHT,SG_INFO,"geodetic_position_v: " << geodetic_position_v);
 617     SG_LOG(SG_FLIGHT,SG_INFO,"euler_angles_v: " << euler_angles_v);
 618
 619     SG_LOG(SG_FLIGHT,SG_INFO,"nlf: " << nlf );
 620     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_wind: " << v_rel_wind );
 621     SG_LOG(SG_FLIGHT,SG_INFO,"v_true_kts: " << v_true_kts );
 622     SG_LOG(SG_FLIGHT,SG_INFO,"v_ground_speed: " << v_ground_speed );
 623     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv_kts: " << v_equiv_kts );
 624     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated_kts: " << v_calibrated_kts );
 625     SG_LOG(SG_FLIGHT,SG_INFO,"alpha: " << alpha );
 626     SG_LOG(SG_FLIGHT,SG_INFO,"beta: " << beta );
 627     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_vert_rad: " << gamma_vert_rad );
 628     SG_LOG(SG_FLIGHT,SG_INFO,"density: " << density );
 629     SG_LOG(SG_FLIGHT,SG_INFO,"mach_number: " << mach_number );
 630     SG_LOG(SG_FLIGHT,SG_INFO,"static_pressure: " << static_pressure );
 631     SG_LOG(SG_FLIGHT,SG_INFO,"total_pressure: " << total_pressure );
 632     SG_LOG(SG_FLIGHT,SG_INFO,"dynamic_pressure: " << dynamic_pressure );
 633     SG_LOG(SG_FLIGHT,SG_INFO,"static_temperature: " << static_temperature );
 634     SG_LOG(SG_FLIGHT,SG_INFO,"total_temperature: " << total_temperature );
 635     SG_LOG(SG_FLIGHT,SG_INFO,"sea_level_radius: " << sea_level_radius );
 636     SG_LOG(SG_FLIGHT,SG_INFO,"earth_position_angle: " << earth_position_angle );
 637     SG_LOG(SG_FLIGHT,SG_INFO,"runway_altitude: " << runway_altitude );
 638     SG_LOG(SG_FLIGHT,SG_INFO,"climb_rate: " << climb_rate );
 639     SG_LOG(SG_FLIGHT,SG_INFO,"altitude_agl: " << altitude_agl );
 640 }
 641
 642 bool
 643 FGInterface::prepare_ground_cache_m(double startSimTime, double endSimTime,
 644                                     const double pt[3], double rad)
 645 {
 646   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 647                                            SGVec3d(pt), rad);
 648 }
 649
 650 bool
 651 FGInterface::prepare_ground_cache_ft(double startSimTime, double endSimTime,
 652                                      const double pt[3], double rad)
 653 {
 654   // Convert units and do the real work.
 655   SGVec3d pt_ft = SG_FEET_TO_METER*SGVec3d(pt);
 656   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 657                                            pt_ft, rad*SG_FEET_TO_METER);
 658 }
 659
 660 bool
 661 FGInterface::is_valid_m(double *ref_time, double pt[3], double *rad)
 662 {
 663   SGVec3d _pt;
 664   bool valid = ground_cache.is_valid(*ref_time, _pt, *rad);
 665   assign(pt, _pt);
 666   return valid;
 667 }
 668
 669 bool FGInterface::is_valid_ft(double *ref_time, double pt[3], double *rad)
 670 {
 671   // Convert units and do the real work.
 672   SGVec3d _pt;
 673   bool found_ground = ground_cache.is_valid(*ref_time, _pt, *rad);
 674   assign(pt, SG_METER_TO_FEET*_pt);
 675   *rad *= SG_METER_TO_FEET;
 676   return found_ground;
 677 }
 678
 679 double
 680 FGInterface::get_cat_m(double t, const double pt[3],
 681                        double end[2][3], double vel[2][3])
 682 {
 683   SGVec3d _end[2], _vel[2];
 684   double dist = ground_cache.get_cat(t, SGVec3d(pt), _end, _vel);
 685   for (int k=0; k<2; ++k) {
 686     assign( end[k], _end[k] );
 687     assign( vel[k], _vel[k] );
 688   }
 689   return dist;
 690 }
 691
 692 double
 693 FGInterface::get_cat_ft(double t, const double pt[3],
 694                         double end[2][3], double vel[2][3])
 695 {
 696   // Convert units and do the real work.
 697   SGVec3d pt_m = SG_FEET_TO_METER*SGVec3d(pt);
 698   SGVec3d _end[2], _vel[2];
 699   double dist = ground_cache.get_cat(t, pt_m, _end, _vel);
 700   for (int k=0; k<2; ++k) {
 701     assign( end[k], SG_METER_TO_FEET*_end[k] );
 702     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 703   }
 704   return dist*SG_METER_TO_FEET;
 705 }
 706
 707 bool
 708 FGInterface::get_body_m(double t, simgear::BVHNode::Id id,
 709                         double bodyToWorld[16], double linearVel[3],
 710                         double angularVel[3])
 711 {
 712   SGMatrixd _bodyToWorld;
 713   SGVec3d _linearVel, _angularVel;
 714   if (!ground_cache.get_body(t, _bodyToWorld, _linearVel, _angularVel, id))
 715     return false;
 716
 717   assign(linearVel, _linearVel);
 718   assign(angularVel, _angularVel);
 719   for (unsigned i = 0; i < 16; ++i)
 720       bodyToWorld[i] = _bodyToWorld.data()[i];
 721
 722   return true;
 723 }
 724
 725 bool
 726 FGInterface::get_agl_m(double t, const double pt[3], double max_altoff,
 727                        double contact[3], double normal[3],
 728                        double linearVel[3], double angularVel[3],
 729                        SGMaterial const*& material, simgear::BVHNode::Id& id)
 730 {
 731   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 732   SGVec3d _contact, _normal, _linearVel, _angularVel;
 733   material = 0;
 734   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 735                                   _angularVel, id, material);
 736   // correct the linear velocity, since the line intersector delivers
 737   // values for the start point and the get_agl function should
 738   // traditionally deliver for the contact point
 739   _linearVel += cross(_angularVel, _contact - pt_m);
 740
 741   assign(contact, _contact);
 742   assign(normal, _normal);
 743   assign(linearVel, _linearVel);
 744   assign(angularVel, _angularVel);
 745   return ret;
 746 }
 747
 748 bool
 749 FGInterface::get_agl_ft(double t, const double pt[3], double max_altoff,
 750                         double contact[3], double normal[3],
 751                         double linearVel[3], double angularVel[3],
 752                         SGMaterial const*& material, simgear::BVHNode::Id& id)
 753 {
 754   // Convert units and do the real work.
 755   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 756   pt_m *= SG_FEET_TO_METER;
 757   SGVec3d _contact, _normal, _linearVel, _angularVel;
 758   material = 0;
 759   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 760                                   _angularVel, id, material);
 761   // correct the linear velocity, since the line intersector delivers
 762   // values for the start point and the get_agl function should
 763   // traditionally deliver for the contact point
 764   _linearVel += cross(_angularVel, _contact - pt_m);
 765
 766   // Convert units back ...
 767   assign( contact, SG_METER_TO_FEET*_contact );
 768   assign( normal, _normal );
 769   assign( linearVel, SG_METER_TO_FEET*_linearVel );
 770   assign( angularVel, _angularVel );
 771   return ret;
 772 }
 773
 774 bool
 775 FGInterface::get_nearest_m(double t, const double pt[3], double maxDist,
 776                            double contact[3], double normal[3],
 777                            double linearVel[3], double angularVel[3],
 778                            SGMaterial const*& material,
 779                            simgear::BVHNode::Id& id)
 780 {
 781   SGVec3d _contact, _linearVel, _angularVel;
 782   if (!ground_cache.get_nearest(t, SGVec3d(pt), maxDist, _contact, _linearVel,
 783                                 _angularVel, id, material))
 784       return false;
 785
 786   assign(contact, _contact);
 787   assign(linearVel, _linearVel);
 788   assign(angularVel, _angularVel);
 789   return true;
 790 }
 791
 792 bool
 793 FGInterface::get_nearest_ft(double t, const double pt[3], double maxDist,
 794                             double contact[3], double normal[3],
 795                             double linearVel[3], double angularVel[3],
 796                             SGMaterial const*& material,
 797                             simgear::BVHNode::Id& id)
 798 {
 799   SGVec3d _contact, _linearVel, _angularVel;
 800   if (!ground_cache.get_nearest(t, SG_FEET_TO_METER*SGVec3d(pt),
 801                                 SG_FEET_TO_METER*maxDist, _contact, _linearVel,
 802                                 _angularVel, id, material))
 803       return false;
 804
 805   assign(contact, SG_METER_TO_FEET*_contact);
 806   assign(linearVel, SG_METER_TO_FEET*_linearVel);
 807   assign(angularVel, _angularVel);
 808   return true;
 809 }
 810
 811 double
 812 FGInterface::get_groundlevel_m(double lat, double lon, double alt)
 813 {
 814   return get_groundlevel_m(SGGeod::fromRadM(lon, lat, alt));
 815 }
 816
 817 double
 818 FGInterface::get_groundlevel_m(const SGGeod& geod)
 819 {
 820   // Compute the cartesian position of the given lat/lon/alt.
 821   SGVec3d pos = SGVec3d::fromGeod(geod);
 822
 823   // FIXME: how to handle t - ref_time differences ???
 824   SGVec3d cpos;
 825   double ref_time = 0, radius;
 826   // Prepare the ground cache for that position.
 827   if (!is_valid_m(&ref_time, cpos.data(), &radius)) {
 828     double startTime = ref_time;
 829     double endTime = startTime + 1;
 830     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), 10);
 831     /// This is most likely the case when the given altitude is
 832     /// too low, try with a new altitude of 10000m, that should be
 833     /// sufficient to find a ground level below everywhere on our planet
 834     if (!ok) {
 835       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 836       /// If there is still no ground, return sea level radius
 837       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), 10))
 838         return 0;
 839     }
 840   } else if (radius*radius <= distSqr(pos, cpos)) {
 841     double startTime = ref_time;
 842     double endTime = startTime + 1;
 843
 844     /// We reuse the old radius value, but only if it is at least 10 Meters ..
 845     if (!(10 < radius)) // Well this strange compare is nan safe
 846       radius = 10;
 847
 848     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), radius);
 849     /// This is most likely the case when the given altitude is
 850     /// too low, try with a new altitude of 10000m, that should be
 851     /// sufficient to find a ground level below everywhere on our planet
 852     if (!ok) {
 853       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 854       /// If there is still no ground, return sea level radius
 855       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), radius))
 856         return 0;
 857     }
 858   }
 859
 860   double contact[3], normal[3], vel[3], angvel[3];
 861   const SGMaterial* material;
 862   simgear::BVHNode::Id id;
 863   // Ignore the return value here, since it just tells us if
 864   // the returns stem from the groundcache or from the coarse
 865   // computations below the groundcache. The contact point is still something
 866   // valid, the normals and the other returns just contain some defaults.
 867   get_agl_m(ref_time, pos.data(), 2.0, contact, normal, vel, angvel,
 868             material, id);
 869   return SGGeod::fromCart(SGVec3d(contact)).getElevationM();
 870 }
 871
 872 bool
 873 FGInterface::caught_wire_m(double t, const double pt[4][3])
 874 {
 875   SGVec3d pt_m[4];
 876   for (int i=0; i<4; ++i)
 877     pt_m[i] = SGVec3d(pt[i]);
 878
 879   return ground_cache.caught_wire(t, pt_m);
 880 }
 881
 882 bool
 883 FGInterface::caught_wire_ft(double t, const double pt[4][3])
 884 {
 885   // Convert units and do the real work.
 886   SGVec3d pt_m[4];
 887   for (int i=0; i<4; ++i)
 888     pt_m[i] = SG_FEET_TO_METER*SGVec3d(pt[i]);
 889
 890   return ground_cache.caught_wire(t, pt_m);
 891 }
 892
 893 bool
 894 FGInterface::get_wire_ends_m(double t, double end[2][3], double vel[2][3])
 895 {
 896   SGVec3d _end[2], _vel[2];
 897   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 898   for (int k=0; k<2; ++k) {
 899     assign( end[k], _end[k] );
 900     assign( vel[k], _vel[k] );
 901   }
 902   return ret;
 903 }
 904
 905 bool
 906 FGInterface::get_wire_ends_ft(double t, double end[2][3], double vel[2][3])
 907 {
 908   // Convert units and do the real work.
 909   SGVec3d _end[2], _vel[2];
 910   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 911   for (int k=0; k<2; ++k) {
 912     assign( end[k], SG_METER_TO_FEET*_end[k] );
 913     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 914   }
 915   return ret;
 916 }
 917
 918 void
 919 FGInterface::release_wire(void)
 920 {
 921   ground_cache.release_wire();
 922 }
 923