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
 282   // Body-axis "euler rates" (rotation speed, but in a funny
 283   // representation).
 284   fgTie("/orientation/roll-rate-degps", this,
 285         &FGInterface::get_Phi_dot_degps);
 286   fgTie("/orientation/pitch-rate-degps", this,
 287         &FGInterface::get_Theta_dot_degps);
 288   fgTie("/orientation/yaw-rate-degps", this,
 289         &FGInterface::get_Psi_dot_degps);
 290
 291                                 // Ground speed knots
 292   fgTie("/velocities/groundspeed-kt", this,
 293         &FGInterface::get_V_ground_speed_kt);
 294
 295                                 // Calibrated airspeed
 296   fgTie("/velocities/airspeed-kt", this,
 297         &FGInterface::get_V_calibrated_kts,
 298         &FGInterface::set_V_calibrated_kts,
 299         false);
 300
 301                                 // Mach number
 302   fgTie("/velocities/mach", this,
 303         &FGInterface::get_Mach_number,
 304         &FGInterface::set_Mach_number,
 305         false);
 306
 307                                 // Local velocities
 308 //   fgTie("/velocities/speed-north-fps", this,
 309 //      &FGInterface::get_V_north,
 310 //      &FGInterface::set_V_north);
 311 //   fgSetArchivable("/velocities/speed-north-fps");
 312 //   fgTie("/velocities/speed-east-fps", this,
 313 //      &FGInterface::get_V_east,
 314 //      &FGInterface::set_V_east);
 315 //   fgSetArchivable("/velocities/speed-east-fps");
 316 //   fgTie("/velocities/speed-down-fps", this,
 317 //      &FGInterface::get_V_down,
 318 //      &FGInterface::set_V_down);
 319 //   fgSetArchivable("/velocities/speed-down-fps");
 320                                 // FIXME: Temporarily read-only, until the
 321                                 // incompatibilities between JSBSim and
 322                                 // LaRCSim are fixed (LaRCSim adds the
 323                                 // earth's rotation to the east velocity).
 324   fgTie("/velocities/speed-north-fps", this,
 325         &FGInterface::get_V_north);
 326   fgTie("/velocities/speed-east-fps", this,
 327         &FGInterface::get_V_east);
 328   fgTie("/velocities/speed-down-fps", this,
 329         &FGInterface::get_V_down);
 330
 331                                 // Relative wind
 332                                 // FIXME: temporarily archivable, until
 333                                 // the NED problem is fixed.
 334   fgTie("/velocities/uBody-fps", this,
 335         &FGInterface::get_uBody,
 336         &FGInterface::set_uBody,
 337         false);
 338   fgSetArchivable("/velocities/uBody-fps");
 339   fgTie("/velocities/vBody-fps", this,
 340         &FGInterface::get_vBody,
 341         &FGInterface::set_vBody,
 342         false);
 343   fgSetArchivable("/velocities/vBody-fps");
 344   fgTie("/velocities/wBody-fps", this,
 345         &FGInterface::get_wBody,
 346         &FGInterface::set_wBody,
 347         false);
 348   fgSetArchivable("/velocities/wBody-fps");
 349
 350                                 // Climb and slip (read-only)
 351   fgTie("/velocities/vertical-speed-fps", this,
 352         &FGInterface::get_Climb_Rate,
 353   &FGInterface::set_Climb_Rate );
 354   fgTie("/velocities/glideslope", this,
 355   &FGInterface::get_Gamma_vert_rad,
 356   &FGInterface::set_Gamma_vert_rad );
 357   fgTie("/orientation/side-slip-rad", this,
 358         &FGInterface::get_Beta); // read-only
 359   fgTie("/orientation/side-slip-deg", this,
 360   &FGInterface::get_Beta_deg); // read-only
 361   fgTie("/orientation/alpha-deg", this,
 362   &FGInterface::get_Alpha_deg); // read-only
 363   fgTie("/accelerations/nlf", this,
 364   &FGInterface::get_Nlf); // read-only
 365
 366                                 // NED accelerations
 367   fgTie("/accelerations/ned/north-accel-fps_sec",
 368         this, &FGInterface::get_V_dot_north);
 369   fgTie("/accelerations/ned/east-accel-fps_sec",
 370         this, &FGInterface::get_V_dot_east);
 371   fgTie("/accelerations/ned/down-accel-fps_sec",
 372         this, &FGInterface::get_V_dot_down);
 373
 374                                 // Pilot accelerations
 375   fgTie("/accelerations/pilot/x-accel-fps_sec",
 376         this, &FGInterface::get_A_X_pilot);
 377   fgTie("/accelerations/pilot/y-accel-fps_sec",
 378         this, &FGInterface::get_A_Y_pilot);
 379   fgTie("/accelerations/pilot/z-accel-fps_sec",
 380         this, &FGInterface::get_A_Z_pilot);
 381
 382 }
 383
 384
 385 /**
 386  * Unbind any properties bound to this FDM.
 387  *
 388  * This method allows the FDM to release properties so that a new
 389  * FDM can bind them instead.
 390  */
 391 void
 392 FGInterface::unbind ()
 393 {
 394   bound = false;
 395
 396   fgUntie("/position/latitude-deg");
 397   fgUntie("/position/longitude-deg");
 398   fgUntie("/position/altitude-ft");
 399   fgUntie("/position/altitude-agl-ft");
 400   fgUntie("/position/ground-elev-ft");
 401   fgUntie("/position/ground-elev-m");
 402   fgUntie("/environment/ground-elevation-m");
 403   fgUntie("/position/sea-level-radius-ft");
 404   fgUntie("/orientation/roll-deg");
 405   fgUntie("/orientation/pitch-deg");
 406   fgUntie("/orientation/heading-deg");
 407   fgUntie("/orientation/roll-rate-degps");
 408   fgUntie("/orientation/pitch-rate-degps");
 409   fgUntie("/orientation/yaw-rate-degps");
 410   fgUntie("/orientation/side-slip-rad");
 411   fgUntie("/orientation/side-slip-deg");
 412   fgUntie("/orientation/alpha-deg");
 413   fgUntie("/velocities/airspeed-kt");
 414   fgUntie("/velocities/groundspeed-kt");
 415   fgUntie("/velocities/mach");
 416   fgUntie("/velocities/speed-north-fps");
 417   fgUntie("/velocities/speed-east-fps");
 418   fgUntie("/velocities/speed-down-fps");
 419   fgUntie("/velocities/uBody-fps");
 420   fgUntie("/velocities/vBody-fps");
 421   fgUntie("/velocities/wBody-fps");
 422   fgUntie("/velocities/vertical-speed-fps");
 423   fgUntie("/velocities/glideslope");
 424   fgUntie("/accelerations/nlf");
 425   fgUntie("/accelerations/pilot/x-accel-fps_sec");
 426   fgUntie("/accelerations/pilot/y-accel-fps_sec");
 427   fgUntie("/accelerations/pilot/z-accel-fps_sec");
 428   fgUntie("/accelerations/ned/north-accel-fps_sec");
 429   fgUntie("/accelerations/ned/east-accel-fps_sec");
 430   fgUntie("/accelerations/ned/down-accel-fps_sec");
 431 }
 432
 433 /**
 434  * Update the state of the FDM (i.e. run the equations of motion).
 435  */
 436 void
 437 FGInterface::update (double dt)
 438 {
 439     SG_LOG(SG_FLIGHT, SG_ALERT, "dummy update() ... SHOULDN'T BE CALLED!");
 440 }
 441
 442
 443 void FGInterface::_updatePositionM(const SGVec3d& cartPos)
 444 {
 445     cartesian_position_v = cartPos;
 446     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 447     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 448     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 449     _update_ground_elev_at_pos();
 450 }
 451
 452
 453 void FGInterface::_updatePosition(const SGGeod& geod)
 454 {
 455     geodetic_position_v = geod;
 456     cartesian_position_v = SGVec3d::fromGeod(geodetic_position_v);
 457     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 458
 459     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 460     _update_ground_elev_at_pos();
 461 }
 462
 463
 464 void FGInterface::_updatePosition(const SGGeoc& geoc)
 465 {
 466     geocentric_position_v = geoc;
 467     cartesian_position_v = SGVec3d::fromGeoc(geocentric_position_v);
 468     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 469
 470     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 471     _update_ground_elev_at_pos();
 472 }
 473
 474
 475 void FGInterface::_updateGeodeticPosition( double lat, double lon, double alt )
 476 {
 477     _updatePosition(SGGeod::fromRadFt(lon, lat, alt));
 478 }
 479
 480
 481 void FGInterface::_updateGeocentricPosition( double lat, double lon,
 482                                              double alt )
 483 {
 484     _updatePosition(SGGeoc::fromRadFt(lon, lat, get_Sea_level_radius() + alt));
 485 }
 486
 487 void FGInterface::_update_ground_elev_at_pos( void ) {
 488     double groundlevel_m = get_groundlevel_m(geodetic_position_v);
 489     _set_Runway_altitude( groundlevel_m * SG_METER_TO_FEET );
 490 }
 491
 492 // Positions
 493 void FGInterface::set_Latitude(double lat) {
 494     geodetic_position_v.setLatitudeRad(lat);
 495 }
 496
 497 void FGInterface::set_Longitude(double lon) {
 498     geodetic_position_v.setLongitudeRad(lon);
 499 }
 500
 501 void FGInterface::set_Altitude(double alt) {
 502     geodetic_position_v.setElevationFt(alt);
 503 }
 504
 505 void FGInterface::set_AltitudeAGL(double altagl) {
 506     altitude_agl=altagl;
 507 }
 508
 509 // Velocities
 510 void FGInterface::set_V_calibrated_kts(double vc) {
 511     v_calibrated_kts = vc;
 512 }
 513
 514 void FGInterface::set_Mach_number(double mach) {
 515     mach_number = mach;
 516 }
 517
 518 void FGInterface::set_Velocities_Local( double north,
 519                                         double east,
 520                                         double down ){
 521     v_local_v[0] = north;
 522     v_local_v[1] = east;
 523     v_local_v[2] = down;
 524 }
 525
 526 void FGInterface::set_Velocities_Wind_Body( double u,
 527                                             double v,
 528                                             double w){
 529     v_wind_body_v[0] = u;
 530     v_wind_body_v[1] = v;
 531     v_wind_body_v[2] = w;
 532 }
 533
 534 // Euler angles
 535 void FGInterface::set_Euler_Angles( double phi,
 536                                     double theta,
 537                                     double psi ) {
 538     euler_angles_v[0] = phi;
 539     euler_angles_v[1] = theta;
 540     euler_angles_v[2] = psi;
 541 }
 542
 543 // Flight Path
 544 void FGInterface::set_Climb_Rate( double roc) {
 545     climb_rate = roc;
 546 }
 547
 548 void FGInterface::set_Gamma_vert_rad( double gamma) {
 549     gamma_vert_rad = gamma;
 550 }
 551
 552 void FGInterface::set_Static_pressure(double p) { static_pressure = p; }
 553 void FGInterface::set_Static_temperature(double T) { static_temperature = T; }
 554 void FGInterface::set_Density(double rho) { density = rho; }
 555
 556 void FGInterface::set_Velocities_Local_Airmass (double wnorth,
 557                                                 double weast,
 558                                                 double wdown ) {
 559     v_local_airmass_v[0] = wnorth;
 560     v_local_airmass_v[1] = weast;
 561     v_local_airmass_v[2] = wdown;
 562 }
 563
 564
 565 void FGInterface::_busdump(void) {
 566
 567     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rp_body_v: " << d_cg_rp_body_v);
 568     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_local_v: " << v_dot_local_v);
 569     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_body_v: " << v_dot_body_v);
 570     SG_LOG(SG_FLIGHT,SG_INFO,"a_cg_body_v: " << a_cg_body_v);
 571     SG_LOG(SG_FLIGHT,SG_INFO,"a_pilot_body_v: " << a_pilot_body_v);
 572     SG_LOG(SG_FLIGHT,SG_INFO,"n_cg_body_v: " << n_cg_body_v);
 573     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_v: " << v_local_v);
 574     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_ground_v: " << v_local_rel_ground_v);
 575     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_airmass_v: " << v_local_airmass_v);
 576     SG_LOG(SG_FLIGHT,SG_INFO,"v_wind_body_v: " << v_wind_body_v);
 577     SG_LOG(SG_FLIGHT,SG_INFO,"omega_body_v: " << omega_body_v);
 578     SG_LOG(SG_FLIGHT,SG_INFO,"euler_rates_v: " << euler_rates_v);
 579     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_rates_v: " << geocentric_rates_v);
 580     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_position_v: " << geocentric_position_v);
 581     SG_LOG(SG_FLIGHT,SG_INFO,"geodetic_position_v: " << geodetic_position_v);
 582     SG_LOG(SG_FLIGHT,SG_INFO,"euler_angles_v: " << euler_angles_v);
 583
 584     SG_LOG(SG_FLIGHT,SG_INFO,"nlf: " << nlf );
 585     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_wind: " << v_rel_wind );
 586     SG_LOG(SG_FLIGHT,SG_INFO,"v_true_kts: " << v_true_kts );
 587     SG_LOG(SG_FLIGHT,SG_INFO,"v_ground_speed: " << v_ground_speed );
 588     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv_kts: " << v_equiv_kts );
 589     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated_kts: " << v_calibrated_kts );
 590     SG_LOG(SG_FLIGHT,SG_INFO,"alpha: " << alpha );
 591     SG_LOG(SG_FLIGHT,SG_INFO,"beta: " << beta );
 592     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_vert_rad: " << gamma_vert_rad );
 593     SG_LOG(SG_FLIGHT,SG_INFO,"density: " << density );
 594     SG_LOG(SG_FLIGHT,SG_INFO,"mach_number: " << mach_number );
 595     SG_LOG(SG_FLIGHT,SG_INFO,"static_pressure: " << static_pressure );
 596     SG_LOG(SG_FLIGHT,SG_INFO,"total_pressure: " << total_pressure );
 597     SG_LOG(SG_FLIGHT,SG_INFO,"dynamic_pressure: " << dynamic_pressure );
 598     SG_LOG(SG_FLIGHT,SG_INFO,"static_temperature: " << static_temperature );
 599     SG_LOG(SG_FLIGHT,SG_INFO,"total_temperature: " << total_temperature );
 600     SG_LOG(SG_FLIGHT,SG_INFO,"sea_level_radius: " << sea_level_radius );
 601     SG_LOG(SG_FLIGHT,SG_INFO,"earth_position_angle: " << earth_position_angle );
 602     SG_LOG(SG_FLIGHT,SG_INFO,"runway_altitude: " << runway_altitude );
 603     SG_LOG(SG_FLIGHT,SG_INFO,"climb_rate: " << climb_rate );
 604     SG_LOG(SG_FLIGHT,SG_INFO,"altitude_agl: " << altitude_agl );
 605 }
 606
 607 bool
 608 FGInterface::prepare_ground_cache_m(double startSimTime, double endSimTime,
 609                                     const double pt[3], double rad)
 610 {
 611   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 612                                            SGVec3d(pt), rad);
 613 }
 614
 615 bool
 616 FGInterface::prepare_ground_cache_ft(double startSimTime, double endSimTime,
 617                                      const double pt[3], double rad)
 618 {
 619   // Convert units and do the real work.
 620   SGVec3d pt_ft = SG_FEET_TO_METER*SGVec3d(pt);
 621   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 622                                            pt_ft, rad*SG_FEET_TO_METER);
 623 }
 624
 625 bool
 626 FGInterface::is_valid_m(double *ref_time, double pt[3], double *rad)
 627 {
 628   SGVec3d _pt;
 629   bool valid = ground_cache.is_valid(*ref_time, _pt, *rad);
 630   assign(pt, _pt);
 631   return valid;
 632 }
 633
 634 bool FGInterface::is_valid_ft(double *ref_time, double pt[3], double *rad)
 635 {
 636   // Convert units and do the real work.
 637   SGVec3d _pt;
 638   bool found_ground = ground_cache.is_valid(*ref_time, _pt, *rad);
 639   assign(pt, SG_METER_TO_FEET*_pt);
 640   *rad *= SG_METER_TO_FEET;
 641   return found_ground;
 642 }
 643
 644 double
 645 FGInterface::get_cat_m(double t, const double pt[3],
 646                        double end[2][3], double vel[2][3])
 647 {
 648   SGVec3d _end[2], _vel[2];
 649   double dist = ground_cache.get_cat(t, SGVec3d(pt), _end, _vel);
 650   for (int k=0; k<2; ++k) {
 651     assign( end[k], _end[k] );
 652     assign( vel[k], _vel[k] );
 653   }
 654   return dist;
 655 }
 656
 657 double
 658 FGInterface::get_cat_ft(double t, const double pt[3],
 659                         double end[2][3], double vel[2][3])
 660 {
 661   // Convert units and do the real work.
 662   SGVec3d pt_m = SG_FEET_TO_METER*SGVec3d(pt);
 663   SGVec3d _end[2], _vel[2];
 664   double dist = ground_cache.get_cat(t, pt_m, _end, _vel);
 665   for (int k=0; k<2; ++k) {
 666     assign( end[k], SG_METER_TO_FEET*_end[k] );
 667     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 668   }
 669   return dist*SG_METER_TO_FEET;
 670 }
 671
 672 bool
 673 FGInterface::get_body_m(double t, simgear::BVHNode::Id id,
 674                         double bodyToWorld[16], double linearVel[3],
 675                         double angularVel[3])
 676 {
 677   SGMatrixd _bodyToWorld;
 678   SGVec3d _linearVel, _angularVel;
 679   if (!ground_cache.get_body(t, _bodyToWorld, _linearVel, _angularVel, id))
 680     return false;
 681
 682   assign(linearVel, _linearVel);
 683   assign(angularVel, _angularVel);
 684   for (unsigned i = 0; i < 16; ++i)
 685       bodyToWorld[i] = _bodyToWorld.data()[i];
 686
 687   return true;
 688 }
 689
 690 bool
 691 FGInterface::get_agl_m(double t, const double pt[3], double max_altoff,
 692                        double contact[3], double normal[3],
 693                        double linearVel[3], double angularVel[3],
 694                        SGMaterial const*& material, simgear::BVHNode::Id& id)
 695 {
 696   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 697   SGVec3d _contact, _normal, _linearVel, _angularVel;
 698   material = 0;
 699   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 700                                   _angularVel, id, material);
 701   // correct the linear velocity, since the line intersector delivers
 702   // values for the start point and the get_agl function should
 703   // traditionally deliver for the contact point
 704   _linearVel += cross(_angularVel, _contact - pt_m);
 705
 706   assign(contact, _contact);
 707   assign(normal, _normal);
 708   assign(linearVel, _linearVel);
 709   assign(angularVel, _angularVel);
 710   return ret;
 711 }
 712
 713 bool
 714 FGInterface::get_agl_ft(double t, const double pt[3], double max_altoff,
 715                         double contact[3], double normal[3],
 716                         double linearVel[3], double angularVel[3],
 717                         SGMaterial const*& material, simgear::BVHNode::Id& id)
 718 {
 719   // Convert units and do the real work.
 720   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 721   pt_m *= SG_FEET_TO_METER;
 722   SGVec3d _contact, _normal, _linearVel, _angularVel;
 723   material = 0;
 724   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 725                                   _angularVel, id, material);
 726   // correct the linear velocity, since the line intersector delivers
 727   // values for the start point and the get_agl function should
 728   // traditionally deliver for the contact point
 729   _linearVel += cross(_angularVel, _contact - pt_m);
 730
 731   // Convert units back ...
 732   assign( contact, SG_METER_TO_FEET*_contact );
 733   assign( normal, _normal );
 734   assign( linearVel, SG_METER_TO_FEET*_linearVel );
 735   assign( angularVel, _angularVel );
 736   return ret;
 737 }
 738
 739 bool
 740 FGInterface::get_nearest_m(double t, const double pt[3], double maxDist,
 741                            double contact[3], double normal[3],
 742                            double linearVel[3], double angularVel[3],
 743                            SGMaterial const*& material,
 744                            simgear::BVHNode::Id& id)
 745 {
 746   SGVec3d _contact, _linearVel, _angularVel;
 747   if (!ground_cache.get_nearest(t, SGVec3d(pt), maxDist, _contact, _linearVel,
 748                                 _angularVel, id, material))
 749       return false;
 750
 751   assign(contact, _contact);
 752   assign(linearVel, _linearVel);
 753   assign(angularVel, _angularVel);
 754   return true;
 755 }
 756
 757 bool
 758 FGInterface::get_nearest_ft(double t, const double pt[3], double maxDist,
 759                             double contact[3], double normal[3],
 760                             double linearVel[3], double angularVel[3],
 761                             SGMaterial const*& material,
 762                             simgear::BVHNode::Id& id)
 763 {
 764   SGVec3d _contact, _linearVel, _angularVel;
 765   if (!ground_cache.get_nearest(t, SG_FEET_TO_METER*SGVec3d(pt),
 766                                 SG_FEET_TO_METER*maxDist, _contact, _linearVel,
 767                                 _angularVel, id, material))
 768       return false;
 769
 770   assign(contact, SG_METER_TO_FEET*_contact);
 771   assign(linearVel, SG_METER_TO_FEET*_linearVel);
 772   assign(angularVel, _angularVel);
 773   return true;
 774 }
 775
 776 double
 777 FGInterface::get_groundlevel_m(double lat, double lon, double alt)
 778 {
 779   return get_groundlevel_m(SGGeod::fromRadM(lon, lat, alt));
 780 }
 781
 782 double
 783 FGInterface::get_groundlevel_m(const SGGeod& geod)
 784 {
 785   // Compute the cartesian position of the given lat/lon/alt.
 786   SGVec3d pos = SGVec3d::fromGeod(geod);
 787
 788   // FIXME: how to handle t - ref_time differences ???
 789   SGVec3d cpos;
 790   double ref_time = 0, radius;
 791   // Prepare the ground cache for that position.
 792   if (!is_valid_m(&ref_time, cpos.data(), &radius)) {
 793     double startTime = ref_time;
 794     double endTime = startTime + 1;
 795     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), 10);
 796     /// This is most likely the case when the given altitude is
 797     /// too low, try with a new altitude of 10000m, that should be
 798     /// sufficient to find a ground level below everywhere on our planet
 799     if (!ok) {
 800       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 801       /// If there is still no ground, return sea level radius
 802       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), 10))
 803         return 0;
 804     }
 805   } else if (radius*radius <= distSqr(pos, cpos)) {
 806     double startTime = ref_time;
 807     double endTime = startTime + 1;
 808
 809     /// We reuse the old radius value, but only if it is at least 10 Meters ..
 810     if (!(10 < radius)) // Well this strange compare is nan safe
 811       radius = 10;
 812
 813     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), radius);
 814     /// This is most likely the case when the given altitude is
 815     /// too low, try with a new altitude of 10000m, that should be
 816     /// sufficient to find a ground level below everywhere on our planet
 817     if (!ok) {
 818       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 819       /// If there is still no ground, return sea level radius
 820       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), radius))
 821         return 0;
 822     }
 823   }
 824
 825   double contact[3], normal[3], vel[3], angvel[3];
 826   const SGMaterial* material;
 827   simgear::BVHNode::Id id;
 828   // Ignore the return value here, since it just tells us if
 829   // the returns stem from the groundcache or from the coarse
 830   // computations below the groundcache. The contact point is still something
 831   // valid, the normals and the other returns just contain some defaults.
 832   get_agl_m(ref_time, pos.data(), 2.0, contact, normal, vel, angvel,
 833             material, id);
 834   return SGGeod::fromCart(SGVec3d(contact)).getElevationM();
 835 }
 836
 837 bool
 838 FGInterface::caught_wire_m(double t, const double pt[4][3])
 839 {
 840   SGVec3d pt_m[4];
 841   for (int i=0; i<4; ++i)
 842     pt_m[i] = SGVec3d(pt[i]);
 843
 844   return ground_cache.caught_wire(t, pt_m);
 845 }
 846
 847 bool
 848 FGInterface::caught_wire_ft(double t, const double pt[4][3])
 849 {
 850   // Convert units and do the real work.
 851   SGVec3d pt_m[4];
 852   for (int i=0; i<4; ++i)
 853     pt_m[i] = SG_FEET_TO_METER*SGVec3d(pt[i]);
 854
 855   return ground_cache.caught_wire(t, pt_m);
 856 }
 857
 858 bool
 859 FGInterface::get_wire_ends_m(double t, double end[2][3], double vel[2][3])
 860 {
 861   SGVec3d _end[2], _vel[2];
 862   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 863   for (int k=0; k<2; ++k) {
 864     assign( end[k], _end[k] );
 865     assign( vel[k], _vel[k] );
 866   }
 867   return ret;
 868 }
 869
 870 bool
 871 FGInterface::get_wire_ends_ft(double t, double end[2][3], double vel[2][3])
 872 {
 873   // Convert units and do the real work.
 874   SGVec3d _end[2], _vel[2];
 875   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 876   for (int k=0; k<2; ++k) {
 877     assign( end[k], SG_METER_TO_FEET*_end[k] );
 878     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 879   }
 880   return ret;
 881 }
 882
 883 void
 884 FGInterface::release_wire(void)
 885 {
 886   ground_cache.release_wire();
 887 }
 888
 889 void fgToggleFDMdataLogging(void) {
 890   cur_fdm_state->ToggleDataLogging();
 891 }