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