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/timing/timestamp.hxx>
  32 #include <simgear/scene/material/mat.hxx>
  33 #include <simgear/io/iochannel.hxx>
  34
  35 #include <Scenery/scenery.hxx>
  36 #include <Main/globals.hxx>
  37 #include <Main/fg_props.hxx>
  38 #include <FDM/groundcache.hxx>
  39
  40
  41 static inline void assign(double* ptr, const SGVec3d& vec)
  42 {
  43   ptr[0] = vec[0];
  44   ptr[1] = vec[1];
  45   ptr[2] = vec[2];
  46 }
  47
  48 // Constructor
  49 FGInterface::FGInterface()
  50 {
  51     _setup();
  52 }
  53
  54 FGInterface::FGInterface( double dt )
  55 {
  56     _setup();
  57 }
  58
  59 // Destructor
  60 FGInterface::~FGInterface() {
  61     // unbind();                   // FIXME: should be called explicitly
  62 }
  63
  64 int
  65 FGInterface::_calc_multiloop (double dt)
  66 {
  67   // Since some time the simulation time increments we get here are
  68   // already a multiple of the basic update frequency.
  69   // So, there is no need to do our own multiloop rounding with all bad
  70   // roundoff problems when we already have nearly accurate values.
  71   // Only the speedup thing must be still handled here
  72   int hz = fgGetInt("/sim/model-hz");
  73   double speedup = fgGetDouble("/sim/speed-up");
  74   double loops = dt * hz * speedup + delta_loops;
  75   int iloops = SGMiscd::roundToInt(loops);
  76   delta_loops = loops-iloops; // delta_loops required for speed-ups < 1 (to do one iteration every n-th step)
  77   return iloops;
  78 }
  79
  80
  81 /**
  82  * Set default values for the state of the FDM.
  83  *
  84  * This method is invoked by the constructors.
  85  */
  86 void
  87 FGInterface::_setup ()
  88 {
  89     inited = false;
  90     bound = false;
  91
  92     _state.d_cg_rp_body_v = SGVec3d::zeros();
  93     _state.v_dot_local_v = SGVec3d::zeros();
  94     _state.v_dot_body_v = SGVec3d::zeros();
  95     _state.a_cg_body_v = SGVec3d::zeros();
  96     _state.a_pilot_body_v = SGVec3d::zeros();
  97     _state.n_cg_body_v = SGVec3d::zeros();
  98     _state.v_local_v = SGVec3d::zeros();
  99     _state.v_local_rel_ground_v = SGVec3d::zeros();
 100     _state.v_local_airmass_v = SGVec3d::zeros();
 101     _state.v_wind_body_v = SGVec3d::zeros();
 102     _state.omega_body_v = SGVec3d::zeros();
 103     _state.euler_rates_v = SGVec3d::zeros();
 104     _state.geocentric_rates_v = SGVec3d::zeros();
 105     _state.geodetic_position_v = SGGeod::fromRadM(0, 0, 0);
 106     _state.cartesian_position_v = SGVec3d::fromGeod(_state.geodetic_position_v);
 107     _state.geocentric_position_v = SGGeoc::fromCart(_state.cartesian_position_v);
 108     _state.euler_angles_v = SGVec3d::zeros();
 109
 110     _state.nlf=0;
 111     _state.v_rel_wind=_state.v_true_kts=0;
 112     _state.v_ground_speed=_state.v_equiv_kts=0;
 113     _state.v_calibrated_kts=0;
 114     _state.alpha=_state.beta=0;
 115     _state.gamma_vert_rad=0;
 116     _state.density=_state.mach_number=0;
 117     _state.static_pressure=_state.total_pressure=0;
 118     _state.dynamic_pressure=0;
 119     _state.static_temperature=_state.total_temperature=0;
 120     _state.sea_level_radius=_state.earth_position_angle=0;
 121     _state.runway_altitude=0;
 122     _state.climb_rate=0;
 123     _state.altitude_agl=0;
 124     _state.track=0;
 125
 126     delta_loops = 0.0;
 127 }
 128
 129 void
 130 FGInterface::init () {}
 131
 132 /**
 133  * Initialize the state of the FDM.
 134  *
 135  * Subclasses of FGInterface may do their own, additional initialization,
 136  * but there is some that is common to all.  Normally, they should call
 137  * this before they begin their own init to make sure the basic structures
 138  * are set up properly.
 139  */
 140 void
 141 FGInterface::common_init ()
 142 {
 143     SG_LOG( SG_FLIGHT, SG_INFO, "Start common FDM init" );
 144
 145     set_inited( true );
 146
 147     ground_cache.set_cache_time_offset(globals->get_sim_time_sec());
 148
 149     // Set initial position
 150     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing position..." );
 151     double lon = fgGetDouble("/sim/presets/longitude-deg")
 152       * SGD_DEGREES_TO_RADIANS;
 153     double lat = fgGetDouble("/sim/presets/latitude-deg")
 154       * SGD_DEGREES_TO_RADIANS;
 155     double alt_ft = fgGetDouble("/sim/presets/altitude-ft");
 156     double alt_m = alt_ft * SG_FEET_TO_METER;
 157     set_Longitude( lon );
 158     set_Latitude( lat );
 159     SG_LOG( SG_FLIGHT, SG_INFO, "Checking for lon = "
 160             << lon*SGD_RADIANS_TO_DEGREES << "deg, lat = "
 161             << lat*SGD_RADIANS_TO_DEGREES << "deg, alt = "
 162             << alt_ft << "ft");
 163
 164     double ground_elev_m = get_groundlevel_m(lat, lon, alt_m);
 165     double ground_elev_ft = ground_elev_m * SG_METER_TO_FEET;
 166     _set_Runway_altitude ( ground_elev_ft );
 167
 168     // Set aircraft altitude
 169     if ( fgGetBool("/sim/presets/onground") || alt_ft < ground_elev_ft ) {
 170         fgSetDouble("/position/altitude-ft", ground_elev_ft + 0.1);
 171         set_Altitude( ground_elev_ft + 0.1);
 172     } else {
 173         set_Altitude( alt_ft );
 174     }
 175
 176     // Set ground elevation
 177     SG_LOG( SG_FLIGHT, SG_INFO,
 178             "...initializing ground elevation to " << ground_elev_ft
 179             << "ft..." );
 180
 181     // Set sea-level radius
 182     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing sea-level radius..." );
 183     SG_LOG( SG_FLIGHT, SG_INFO, " lat = "
 184             << fgGetDouble("/sim/presets/latitude-deg")
 185             << " alt = " << get_Altitude() );
 186     double slr = SGGeodesy::SGGeodToSeaLevelRadius(_state.geodetic_position_v);
 187     _set_Sea_level_radius( slr * SG_METER_TO_FEET );
 188
 189     // Set initial Euler angles
 190     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing Euler angles..." );
 191     set_Euler_Angles( fgGetDouble("/sim/presets/roll-deg")
 192                         * SGD_DEGREES_TO_RADIANS,
 193                       fgGetDouble("/sim/presets/pitch-deg")
 194                         * SGD_DEGREES_TO_RADIANS,
 195                       fgGetDouble("/sim/presets/heading-deg")
 196                         * SGD_DEGREES_TO_RADIANS );
 197
 198     // Set initial velocities
 199     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing velocities..." );
 200     if ( !fgHasNode("/sim/presets/speed-set") ) {
 201         set_V_calibrated_kts(0.0);
 202     } else {
 203         const std::string speedset = fgGetString("/sim/presets/speed-set");
 204         if ( speedset == "knots" || speedset == "KNOTS" ) {
 205             set_V_calibrated_kts( fgGetDouble("/sim/presets/airspeed-kt") );
 206         } else if ( speedset == "mach" || speedset == "MACH" ) {
 207             set_Mach_number( fgGetDouble("/sim/presets/mach") );
 208         } else if ( speedset == "UVW" || speedset == "uvw" ) {
 209             set_Velocities_Wind_Body(
 210                                      fgGetDouble("/sim/presets/uBody-fps"),
 211                                      fgGetDouble("/sim/presets/vBody-fps"),
 212                                      fgGetDouble("/sim/presets/wBody-fps") );
 213         } else if ( speedset == "NED" || speedset == "ned" ) {
 214             set_Velocities_Local(
 215                                  fgGetDouble("/sim/presets/speed-north-fps"),
 216                                  fgGetDouble("/sim/presets/speed-east-fps"),
 217                                  fgGetDouble("/sim/presets/speed-down-fps") );
 218         } else {
 219             SG_LOG( SG_FLIGHT, SG_ALERT,
 220                     "Unrecognized value for /sim/presets/speed-set: "
 221                     << speedset);
 222             set_V_calibrated_kts( 0.0 );
 223         }
 224     }
 225
 226     if ( fgHasNode("/sim/presets/glideslope-deg") )
 227         set_Gamma_vert_rad( fgGetDouble("/sim/presets/glideslope-deg")
 228                               * SGD_DEGREES_TO_RADIANS );
 229     else if ( fgHasNode("/sim/presets/speed-set") &&
 230               fgHasNode( "/sim/presets/vertical-speed-fps") )
 231     {
 232         set_Climb_Rate( fgGetDouble("/sim/presets/vertical-speed-fps") );
 233     }
 234
 235     SG_LOG( SG_FLIGHT, SG_INFO, "End common FDM init" );
 236 }
 237
 238
 239 /**
 240  * Bind getters and setters to properties.
 241  *
 242  * The bind() method will be invoked after init().  Note that unlike
 243  * the usual implementations of FGSubsystem::bind(), this method does
 244  * not automatically pick up existing values for the properties at
 245  * bind time; instead, all values are set explicitly in the init()
 246  * method.
 247  */
 248 void
 249 FGInterface::bind ()
 250 {
 251   bound = true;
 252
 253   _tiedProperties.setRoot(globals->get_props());
 254   // Aircraft position
 255   _tiedProperties.Tie("/position/latitude-deg", this,
 256                       &FGInterface::get_Latitude_deg,
 257                       &FGInterface::set_Latitude_deg,
 258                       false);
 259   fgSetArchivable("/position/latitude-deg");
 260   _tiedProperties.Tie("/position/longitude-deg", this,
 261                       &FGInterface::get_Longitude_deg,
 262                       &FGInterface::set_Longitude_deg,
 263                       false);
 264   fgSetArchivable("/position/longitude-deg");
 265   _tiedProperties.Tie("/position/altitude-ft", this,
 266                       &FGInterface::get_Altitude,
 267                       &FGInterface::set_Altitude,
 268                       false);
 269   fgSetArchivable("/position/altitude-ft");
 270   _tiedProperties.Tie("/position/altitude-agl-ft", this,
 271                       &FGInterface::get_Altitude_AGL, &FGInterface::set_AltitudeAGL, false);
 272   fgSetArchivable("/position/ground-elev-ft");
 273   _tiedProperties.Tie("/position/ground-elev-ft", this,
 274                       &FGInterface::get_Runway_altitude); // read-only
 275   fgSetArchivable("/position/ground-elev-m");
 276   _tiedProperties.Tie("/position/ground-elev-m", this,
 277                       &FGInterface::get_Runway_altitude_m); // read-only
 278   _tiedProperties.Tie("/environment/ground-elevation-m", this,
 279                       &FGInterface::get_Runway_altitude_m); // read-only
 280   fgSetArchivable("/position/sea-level-radius-ft");
 281   _tiedProperties.Tie("/position/sea-level-radius-ft", this,
 282                       &FGInterface::get_Sea_level_radius,
 283                       &FGInterface::_set_Sea_level_radius, false);
 284
 285   // Orientation
 286   _tiedProperties.Tie("/orientation/roll-deg", this,
 287                       &FGInterface::get_Phi_deg,
 288                       &FGInterface::set_Phi_deg, false);
 289   fgSetArchivable("/orientation/roll-deg");
 290   _tiedProperties.Tie("/orientation/pitch-deg", this,
 291                       &FGInterface::get_Theta_deg,
 292                       &FGInterface::set_Theta_deg, false);
 293   fgSetArchivable("/orientation/pitch-deg");
 294   _tiedProperties.Tie("/orientation/heading-deg", this,
 295                       &FGInterface::get_Psi_deg,
 296                       &FGInterface::set_Psi_deg, false);
 297   fgSetArchivable("/orientation/heading-deg");
 298   _tiedProperties.Tie("/orientation/track-deg", this,
 299                       &FGInterface::get_Track); // read-only
 300
 301   // Body-axis "euler rates" (rotation speed, but in a funny
 302   // representation).
 303   _tiedProperties.Tie("/orientation/roll-rate-degps", this,
 304                       &FGInterface::get_Phi_dot_degps,
 305                       &FGInterface::set_Phi_dot_degps, false);
 306   _tiedProperties.Tie("/orientation/pitch-rate-degps", this,
 307                       &FGInterface::get_Theta_dot_degps,
 308                       &FGInterface::set_Theta_dot_degps, false);
 309   _tiedProperties.Tie("/orientation/yaw-rate-degps", this,
 310                       &FGInterface::get_Psi_dot_degps,
 311                       &FGInterface::set_Psi_dot_degps, false);
 312
 313   _tiedProperties.Tie("/orientation/p-body", this, &FGInterface::get_P_body); // read-only
 314   _tiedProperties.Tie("/orientation/q-body", this, &FGInterface::get_Q_body); // read-only
 315   _tiedProperties.Tie("/orientation/r-body", this, &FGInterface::get_R_body); // read-only
 316
 317   // Ground speed knots
 318   _tiedProperties.Tie("/velocities/groundspeed-kt", this,
 319                       &FGInterface::get_V_ground_speed_kt,
 320                       &FGInterface::set_V_ground_speed_kt); // read-only
 321
 322   // Calibrated airspeed
 323   _tiedProperties.Tie("/velocities/airspeed-kt", this,
 324                       &FGInterface::get_V_calibrated_kts,
 325                       &FGInterface::set_V_calibrated_kts,
 326                       false);
 327
 328   _tiedProperties.Tie("/velocities/equivalent-kt", this,
 329                       &FGInterface::get_V_equiv_kts); // read-only
 330
 331   // Mach number
 332   _tiedProperties.Tie("/velocities/mach", this,
 333                       &FGInterface::get_Mach_number,
 334                       &FGInterface::set_Mach_number,
 335                       false);
 336
 337   // Local velocities
 338 //   _tiedProperties.Tie("/velocities/speed-north-fps", this,
 339 //                       &FGInterface::get_V_north,
 340 //                       &FGInterface::set_V_north);
 341 //   fgSetArchivable("/velocities/speed-north-fps");
 342 //   _tiedProperties.Tie("/velocities/speed-east-fps", this,
 343 //                       &FGInterface::get_V_east,
 344 //                       &FGInterface::set_V_east);
 345 //   fgSetArchivable("/velocities/speed-east-fps");
 346 //   _tiedProperties.Tie("/velocities/speed-down-fps", this,
 347 //                       &FGInterface::get_V_down,
 348 //                       &FGInterface::set_V_down);
 349 //   fgSetArchivable("/velocities/speed-down-fps");
 350
 351   // FIXME: Temporarily read-only, until the
 352   // incompatibilities between JSBSim and
 353   // LaRCSim are fixed (LaRCSim adds the
 354   // earth's rotation to the east velocity).
 355   _tiedProperties.Tie("/velocities/speed-north-fps", this,
 356                       &FGInterface::get_V_north, &FGInterface::set_V_north, false);
 357   _tiedProperties.Tie("/velocities/speed-east-fps", this,
 358                       &FGInterface::get_V_east, &FGInterface::set_V_east, false);
 359   _tiedProperties.Tie("/velocities/speed-down-fps", this,
 360                       &FGInterface::get_V_down, &FGInterface::set_V_down, false);
 361
 362   _tiedProperties.Tie("/velocities/north-relground-fps", this,
 363                       &FGInterface::get_V_north_rel_ground); // read-only
 364   _tiedProperties.Tie("/velocities/east-relground-fps", this,
 365                       &FGInterface::get_V_east_rel_ground); // read-only
 366   _tiedProperties.Tie("/velocities/down-relground-fps", this,
 367                       &FGInterface::get_V_down_rel_ground); // read-only
 368
 369   // Relative wind
 370   // FIXME: temporarily archivable, until the NED problem is fixed.
 371   _tiedProperties.Tie("/velocities/uBody-fps", this,
 372                       &FGInterface::get_uBody,
 373                       &FGInterface::set_uBody,
 374                       false);
 375   fgSetArchivable("/velocities/uBody-fps");
 376   _tiedProperties.Tie("/velocities/vBody-fps", this,
 377                       &FGInterface::get_vBody,
 378                       &FGInterface::set_vBody,
 379                       false);
 380   fgSetArchivable("/velocities/vBody-fps");
 381   _tiedProperties.Tie("/velocities/wBody-fps", this,
 382                       &FGInterface::get_wBody,
 383                       &FGInterface::set_wBody,
 384                       false);
 385   fgSetArchivable("/velocities/wBody-fps");
 386
 387   // Climb and slip (read-only)
 388   _tiedProperties.Tie("/velocities/vertical-speed-fps", this,
 389                       &FGInterface::get_Climb_Rate,
 390                       &FGInterface::set_Climb_Rate, false );
 391   _tiedProperties.Tie("/velocities/glideslope", this,
 392                       &FGInterface::get_Gamma_vert_rad,
 393                       &FGInterface::set_Gamma_vert_rad, false );
 394   _tiedProperties.Tie("/orientation/side-slip-rad", this,
 395                       &FGInterface::get_Beta, &FGInterface::_set_Beta, false);
 396   _tiedProperties.Tie("/orientation/side-slip-deg", this,
 397                       &FGInterface::get_Beta_deg); // read-only
 398   _tiedProperties.Tie("/orientation/alpha-deg", this,
 399                       &FGInterface::get_Alpha_deg, &FGInterface::set_Alpha_deg, false);
 400   _tiedProperties.Tie("/accelerations/nlf", this,
 401                       &FGInterface::get_Nlf); // read-only
 402
 403   // NED accelerations
 404   _tiedProperties.Tie("/accelerations/ned/north-accel-fps_sec",
 405                       this, &FGInterface::get_V_dot_north); // read-only
 406   _tiedProperties.Tie("/accelerations/ned/east-accel-fps_sec",
 407                       this, &FGInterface::get_V_dot_east); // read-only
 408   _tiedProperties.Tie("/accelerations/ned/down-accel-fps_sec",
 409                       this, &FGInterface::get_V_dot_down); // read-only
 410
 411   // Pilot accelerations
 412   _tiedProperties.Tie("/accelerations/pilot/x-accel-fps_sec",
 413                       this, &FGInterface::get_A_X_pilot, &FGInterface::set_A_X_pilot, false);
 414   _tiedProperties.Tie("/accelerations/pilot/y-accel-fps_sec",
 415                       this, &FGInterface::get_A_Y_pilot, &FGInterface::set_A_Y_pilot, false);
 416   _tiedProperties.Tie("/accelerations/pilot/z-accel-fps_sec",
 417                       this, &FGInterface::get_A_Z_pilot, &FGInterface::set_A_Z_pilot, false);
 418
 419   _tiedProperties.Tie("/accelerations/n-z-cg-fps_sec",
 420                       this, &FGInterface::get_N_Z_cg); // read-only
 421 }
 422
 423
 424 /**
 425  * Unbind any properties bound to this FDM.
 426  *
 427  * This method allows the FDM to release properties so that a new
 428  * FDM can bind them instead.
 429  */
 430 void
 431 FGInterface::unbind ()
 432 {
 433   _tiedProperties.Untie();
 434   bound = false;
 435 }
 436
 437 /**
 438  * Update the state of the FDM (i.e. run the equations of motion).
 439  */
 440 void
 441 FGInterface::update (double dt)
 442 {
 443     SG_LOG(SG_FLIGHT, SG_ALERT, "dummy update() ... SHOULDN'T BE CALLED!");
 444 }
 445
 446 bool FGInterface::readState(SGIOChannel* io)
 447 {
 448     FlightState buf;
 449     int length = sizeof(FlightState);
 450
 451     if ( io->get_type() == sgFileType ) {
 452             if ( io->read( (char *)(& buf), length ) == length ) {
 453             SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 454             } else {
 455             return false;
 456         }
 457         } else {
 458             while ( io->read( (char *)(& buf), length ) == length ) {
 459             SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 460             }
 461         }
 462
 463     _state = buf; // copy the read state over
 464     return true;
 465 }
 466
 467 bool FGInterface::writeState(SGIOChannel* io)
 468 {
 469     if (!bound || !inited) {
 470         return false;
 471     }
 472
 473     int length = sizeof(FlightState);
 474     if ( ! io->write( (char *)(& _state), length ) ) {
 475             SG_LOG( SG_IO, SG_ALERT, "Error writing data." );
 476             return false;
 477         }
 478
 479     return true;
 480 }
 481
 482 void FGInterface::_updatePositionM(const SGVec3d& cartPos)
 483 {
 484     TrackComputer tracker( _state.track, _state.geodetic_position_v );
 485     _state.cartesian_position_v = cartPos;
 486     _state.geodetic_position_v = SGGeod::fromCart(_state.cartesian_position_v);
 487     _state.geocentric_position_v = SGGeoc::fromCart(_state.cartesian_position_v);
 488     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(_state.geodetic_position_v)*SG_METER_TO_FEET );
 489     _update_ground_elev_at_pos();
 490 }
 491
 492
 493 void FGInterface::_updatePosition(const SGGeod& geod)
 494 {
 495     TrackComputer tracker( _state.track, _state.geodetic_position_v );
 496     _state.geodetic_position_v = geod;
 497     _state.cartesian_position_v = SGVec3d::fromGeod(_state.geodetic_position_v);
 498     _state.geocentric_position_v = SGGeoc::fromCart(_state.cartesian_position_v);
 499
 500     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(_state.geodetic_position_v)*SG_METER_TO_FEET );
 501     _update_ground_elev_at_pos();
 502 }
 503
 504
 505 void FGInterface::_updatePosition(const SGGeoc& geoc)
 506 {
 507     TrackComputer tracker( _state.track, _state.geodetic_position_v );
 508     _state.geocentric_position_v = geoc;
 509     _state.cartesian_position_v = SGVec3d::fromGeoc(_state.geocentric_position_v);
 510     _state.geodetic_position_v = SGGeod::fromCart(_state.cartesian_position_v);
 511
 512     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(_state.geodetic_position_v)*SG_METER_TO_FEET );
 513     _update_ground_elev_at_pos();
 514 }
 515
 516
 517 void FGInterface::_updateGeodeticPosition( double lat, double lon, double alt )
 518 {
 519     _updatePosition(SGGeod::fromRadFt(lon, lat, alt));
 520 }
 521
 522
 523 void FGInterface::_updateGeocentricPosition( double lat, double lon,
 524                                              double alt )
 525 {
 526     _updatePosition(SGGeoc::fromRadFt(lon, lat, get_Sea_level_radius() + alt));
 527 }
 528
 529 void FGInterface::_update_ground_elev_at_pos( void ) {
 530     double groundlevel_m = get_groundlevel_m(_state.geodetic_position_v);
 531     _set_Runway_altitude( groundlevel_m * SG_METER_TO_FEET );
 532 }
 533
 534 // Positions
 535 void FGInterface::set_Latitude(double lat) {
 536     _state.geodetic_position_v.setLatitudeRad(lat);
 537 }
 538
 539 void FGInterface::set_Longitude(double lon) {
 540     _state.geodetic_position_v.setLongitudeRad(lon);
 541 }
 542
 543 void FGInterface::set_Altitude(double alt) {
 544     _state.geodetic_position_v.setElevationFt(alt);
 545 }
 546
 547 void FGInterface::set_AltitudeAGL(double altagl) {
 548     _state.altitude_agl=altagl;
 549 }
 550
 551 // Velocities
 552 void FGInterface::set_V_calibrated_kts(double vc) {
 553     _state.v_calibrated_kts = vc;
 554 }
 555
 556 void FGInterface::set_Mach_number(double mach) {
 557     _state.mach_number = mach;
 558 }
 559
 560 void FGInterface::set_Velocities_Local( double north,
 561                                         double east,
 562                                         double down ){
 563     _state.v_local_v[0] = north;
 564     _state.v_local_v[1] = east;
 565     _state.v_local_v[2] = down;
 566 }
 567
 568 void FGInterface::set_Velocities_Wind_Body( double u,
 569                                             double v,
 570                                             double w){
 571     _state.v_wind_body_v[0] = u;
 572     _state.v_wind_body_v[1] = v;
 573     _state.v_wind_body_v[2] = w;
 574 }
 575
 576 // Euler angles
 577 void FGInterface::set_Euler_Angles( double phi,
 578                                     double theta,
 579                                     double psi ) {
 580     _state.euler_angles_v[0] = phi;
 581     _state.euler_angles_v[1] = theta;
 582     _state.euler_angles_v[2] = psi;
 583 }
 584
 585 // Flight Path
 586 void FGInterface::set_Climb_Rate( double roc) {
 587     _state.climb_rate = roc;
 588 }
 589
 590 void FGInterface::set_Gamma_vert_rad( double gamma) {
 591     _state.gamma_vert_rad = gamma;
 592 }
 593
 594 void FGInterface::set_Static_pressure(double p) { _state.static_pressure = p; }
 595 void FGInterface::set_Static_temperature(double T) { _state.static_temperature = T; }
 596 void FGInterface::set_Density(double rho) { _state.density = rho; }
 597
 598 void FGInterface::set_Velocities_Local_Airmass (double wnorth,
 599                                                 double weast,
 600                                                 double wdown ) {
 601     _state.v_local_airmass_v[0] = wnorth;
 602     _state.v_local_airmass_v[1] = weast;
 603     _state.v_local_airmass_v[2] = wdown;
 604 }
 605
 606
 607 void FGInterface::_busdump(void)
 608 {
 609     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rp_body_v: " << _state.d_cg_rp_body_v);
 610     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_local_v: " << _state.v_dot_local_v);
 611     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_body_v: " << _state.v_dot_body_v);
 612     SG_LOG(SG_FLIGHT,SG_INFO,"a_cg_body_v: " << _state.a_cg_body_v);
 613     SG_LOG(SG_FLIGHT,SG_INFO,"a_pilot_body_v: " << _state.a_pilot_body_v);
 614     SG_LOG(SG_FLIGHT,SG_INFO,"n_cg_body_v: " << _state.n_cg_body_v);
 615     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_v: " << _state.v_local_v);
 616     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_ground_v: " << _state.v_local_rel_ground_v);
 617     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_airmass_v: " << _state.v_local_airmass_v);
 618     SG_LOG(SG_FLIGHT,SG_INFO,"v_wind_body_v: " << _state.v_wind_body_v);
 619     SG_LOG(SG_FLIGHT,SG_INFO,"omega_body_v: " << _state.omega_body_v);
 620     SG_LOG(SG_FLIGHT,SG_INFO,"euler_rates_v: " << _state.euler_rates_v);
 621     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_rates_v: " << _state.geocentric_rates_v);
 622     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_position_v: " << _state.geocentric_position_v);
 623     SG_LOG(SG_FLIGHT,SG_INFO,"geodetic_position_v: " << _state.geodetic_position_v);
 624     SG_LOG(SG_FLIGHT,SG_INFO,"euler_angles_v: " << _state.euler_angles_v);
 625
 626     SG_LOG(SG_FLIGHT,SG_INFO,"nlf: " << _state.nlf );
 627     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_wind: " << _state.v_rel_wind );
 628     SG_LOG(SG_FLIGHT,SG_INFO,"v_true_kts: " << _state.v_true_kts );
 629     SG_LOG(SG_FLIGHT,SG_INFO,"v_ground_speed: " << _state.v_ground_speed );
 630     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv_kts: " << _state.v_equiv_kts );
 631     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated_kts: " << _state.v_calibrated_kts );
 632     SG_LOG(SG_FLIGHT,SG_INFO,"alpha: " << _state.alpha );
 633     SG_LOG(SG_FLIGHT,SG_INFO,"beta: " << _state.beta );
 634     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_vert_rad: " << _state.gamma_vert_rad );
 635     SG_LOG(SG_FLIGHT,SG_INFO,"density: " << _state.density );
 636     SG_LOG(SG_FLIGHT,SG_INFO,"mach_number: " << _state.mach_number );
 637     SG_LOG(SG_FLIGHT,SG_INFO,"static_pressure: " << _state.static_pressure );
 638     SG_LOG(SG_FLIGHT,SG_INFO,"total_pressure: " << _state.total_pressure );
 639     SG_LOG(SG_FLIGHT,SG_INFO,"dynamic_pressure: " << _state.dynamic_pressure );
 640     SG_LOG(SG_FLIGHT,SG_INFO,"static_temperature: " << _state.static_temperature );
 641     SG_LOG(SG_FLIGHT,SG_INFO,"total_temperature: " << _state.total_temperature );
 642     SG_LOG(SG_FLIGHT,SG_INFO,"sea_level_radius: " << _state.sea_level_radius );
 643     SG_LOG(SG_FLIGHT,SG_INFO,"earth_position_angle: " << _state.earth_position_angle );
 644     SG_LOG(SG_FLIGHT,SG_INFO,"runway_altitude: " << _state.runway_altitude );
 645     SG_LOG(SG_FLIGHT,SG_INFO,"climb_rate: " << _state.climb_rate );
 646     SG_LOG(SG_FLIGHT,SG_INFO,"altitude_agl: " << _state.altitude_agl );
 647 }
 648
 649 bool
 650 FGInterface::prepare_ground_cache_m(double startSimTime, double endSimTime,
 651                                     const double pt[3], double rad)
 652 {
 653   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 654                                            SGVec3d(pt), rad);
 655 }
 656
 657 bool
 658 FGInterface::prepare_ground_cache_ft(double startSimTime, double endSimTime,
 659                                      const double pt[3], double rad)
 660 {
 661   // Convert units and do the real work.
 662   SGVec3d pt_ft = SG_FEET_TO_METER*SGVec3d(pt);
 663   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 664                                            pt_ft, rad*SG_FEET_TO_METER);
 665 }
 666
 667 bool
 668 FGInterface::is_valid_m(double *ref_time, double pt[3], double *rad)
 669 {
 670   SGVec3d _pt;
 671   bool valid = ground_cache.is_valid(*ref_time, _pt, *rad);
 672   assign(pt, _pt);
 673   return valid;
 674 }
 675
 676 bool FGInterface::is_valid_ft(double *ref_time, double pt[3], double *rad)
 677 {
 678   // Convert units and do the real work.
 679   SGVec3d _pt;
 680   bool found_ground = ground_cache.is_valid(*ref_time, _pt, *rad);
 681   assign(pt, SG_METER_TO_FEET*_pt);
 682   *rad *= SG_METER_TO_FEET;
 683   return found_ground;
 684 }
 685
 686 double
 687 FGInterface::get_cat_m(double t, const double pt[3],
 688                        double end[2][3], double vel[2][3])
 689 {
 690   SGVec3d _end[2], _vel[2];
 691   double dist = ground_cache.get_cat(t, SGVec3d(pt), _end, _vel);
 692   for (int k=0; k<2; ++k) {
 693     assign( end[k], _end[k] );
 694     assign( vel[k], _vel[k] );
 695   }
 696   return dist;
 697 }
 698
 699 double
 700 FGInterface::get_cat_ft(double t, const double pt[3],
 701                         double end[2][3], double vel[2][3])
 702 {
 703   // Convert units and do the real work.
 704   SGVec3d pt_m = SG_FEET_TO_METER*SGVec3d(pt);
 705   SGVec3d _end[2], _vel[2];
 706   double dist = ground_cache.get_cat(t, pt_m, _end, _vel);
 707   for (int k=0; k<2; ++k) {
 708     assign( end[k], SG_METER_TO_FEET*_end[k] );
 709     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 710   }
 711   return dist*SG_METER_TO_FEET;
 712 }
 713
 714 bool
 715 FGInterface::get_body_m(double t, simgear::BVHNode::Id id,
 716                         double bodyToWorld[16], double linearVel[3],
 717                         double angularVel[3])
 718 {
 719   SGMatrixd _bodyToWorld;
 720   SGVec3d _linearVel, _angularVel;
 721   if (!ground_cache.get_body(t, _bodyToWorld, _linearVel, _angularVel, id))
 722     return false;
 723
 724   assign(linearVel, _linearVel);
 725   assign(angularVel, _angularVel);
 726   for (unsigned i = 0; i < 16; ++i)
 727       bodyToWorld[i] = _bodyToWorld.data()[i];
 728
 729   return true;
 730 }
 731
 732 bool
 733 FGInterface::get_agl_m(double t, const double pt[3], double max_altoff,
 734                        double contact[3], double normal[3],
 735                        double linearVel[3], double angularVel[3],
 736                        simgear::BVHMaterial const*& material, simgear::BVHNode::Id& id)
 737 {
 738   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 739   SGVec3d _contact, _normal, _linearVel, _angularVel;
 740   material = 0;
 741   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 742                                   _angularVel, id, material);
 743   // correct the linear velocity, since the line intersector delivers
 744   // values for the start point and the get_agl function should
 745   // traditionally deliver for the contact point
 746   _linearVel += cross(_angularVel, _contact - pt_m);
 747
 748   assign(contact, _contact);
 749   assign(normal, _normal);
 750   assign(linearVel, _linearVel);
 751   assign(angularVel, _angularVel);
 752   return ret;
 753 }
 754
 755 bool
 756 FGInterface::get_agl_ft(double t, const double pt[3], double max_altoff,
 757                         double contact[3], double normal[3],
 758                         double linearVel[3], double angularVel[3],
 759                         simgear::BVHMaterial const*& material, simgear::BVHNode::Id& id)
 760 {
 761   // Convert units and do the real work.
 762   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 763   pt_m *= SG_FEET_TO_METER;
 764   SGVec3d _contact, _normal, _linearVel, _angularVel;
 765   material = 0;
 766   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 767                                   _angularVel, id, material);
 768   // correct the linear velocity, since the line intersector delivers
 769   // values for the start point and the get_agl function should
 770   // traditionally deliver for the contact point
 771   _linearVel += cross(_angularVel, _contact - pt_m);
 772
 773   // Convert units back ...
 774   assign( contact, SG_METER_TO_FEET*_contact );
 775   assign( normal, _normal );
 776   assign( linearVel, SG_METER_TO_FEET*_linearVel );
 777   assign( angularVel, _angularVel );
 778   return ret;
 779 }
 780
 781 bool
 782 FGInterface::get_nearest_m(double t, const double pt[3], double maxDist,
 783                            double contact[3], double normal[3],
 784                            double linearVel[3], double angularVel[3],
 785                            simgear::BVHMaterial const*& material,
 786                            simgear::BVHNode::Id& id)
 787 {
 788   SGVec3d _contact, _linearVel, _angularVel;
 789   material = 0;
 790   if (!ground_cache.get_nearest(t, SGVec3d(pt), maxDist, _contact, _linearVel,
 791                                 _angularVel, id, material))
 792       return false;
 793
 794   assign(contact, _contact);
 795   assign(linearVel, _linearVel);
 796   assign(angularVel, _angularVel);
 797   return true;
 798 }
 799
 800 bool
 801 FGInterface::get_nearest_ft(double t, const double pt[3], double maxDist,
 802                             double contact[3], double normal[3],
 803                             double linearVel[3], double angularVel[3],
 804                             simgear::BVHMaterial const*& material,
 805                             simgear::BVHNode::Id& id)
 806 {
 807   SGVec3d _contact, _linearVel, _angularVel;
 808   material = 0;
 809   if (!ground_cache.get_nearest(t, SG_FEET_TO_METER*SGVec3d(pt),
 810                                 SG_FEET_TO_METER*maxDist, _contact, _linearVel,
 811                                 _angularVel, id, material))
 812       return false;
 813
 814   assign(contact, SG_METER_TO_FEET*_contact);
 815   assign(linearVel, SG_METER_TO_FEET*_linearVel);
 816   assign(angularVel, _angularVel);
 817   return true;
 818 }
 819
 820 double
 821 FGInterface::get_groundlevel_m(double lat, double lon, double alt)
 822 {
 823   return get_groundlevel_m(SGGeod::fromRadM(lon, lat, alt));
 824 }
 825
 826 double
 827 FGInterface::get_groundlevel_m(const SGGeod& geod)
 828 {
 829   // Compute the cartesian position of the given lat/lon/alt.
 830   SGVec3d pos = SGVec3d::fromGeod(geod);
 831
 832   // FIXME: how to handle t - ref_time differences ???
 833   SGVec3d cpos;
 834   double ref_time = 0, radius;
 835   // Prepare the ground cache for that position.
 836   if (!is_valid_m(&ref_time, cpos.data(), &radius)) {
 837     double startTime = ref_time;
 838     double endTime = startTime + 1;
 839     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), 10);
 840     /// This is most likely the case when the given altitude is
 841     /// too low, try with a new altitude of 10000m, that should be
 842     /// sufficient to find a ground level below everywhere on our planet
 843     if (!ok) {
 844       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 845       /// If there is still no ground, return sea level radius
 846       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), 10))
 847         return 0;
 848     }
 849   } else if (radius*radius <= distSqr(pos, cpos)) {
 850     double startTime = ref_time;
 851     double endTime = startTime + 1;
 852
 853     /// We reuse the old radius value, but only if it is at least 10 Meters ..
 854     if (!(10 < radius)) // Well this strange compare is nan safe
 855       radius = 10;
 856
 857     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), radius);
 858     /// This is most likely the case when the given altitude is
 859     /// too low, try with a new altitude of 10000m, that should be
 860     /// sufficient to find a ground level below everywhere on our planet
 861     if (!ok) {
 862       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 863       /// If there is still no ground, return sea level radius
 864       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), radius))
 865         return 0;
 866     }
 867   }
 868
 869   double contact[3], normal[3], vel[3], angvel[3];
 870   const simgear::BVHMaterial* material;
 871   simgear::BVHNode::Id id;
 872   // Ignore the return value here, since it just tells us if
 873   // the returns stem from the groundcache or from the coarse
 874   // computations below the groundcache. The contact point is still something
 875   // valid, the normals and the other returns just contain some defaults.
 876   get_agl_m(ref_time, pos.data(), 2.0, contact, normal, vel, angvel,
 877             material, id);
 878   return SGGeod::fromCart(SGVec3d(contact)).getElevationM();
 879 }
 880
 881 bool
 882 FGInterface::caught_wire_m(double t, const double pt[4][3])
 883 {
 884   SGVec3d pt_m[4];
 885   for (int i=0; i<4; ++i)
 886     pt_m[i] = SGVec3d(pt[i]);
 887
 888   return ground_cache.caught_wire(t, pt_m);
 889 }
 890
 891 bool
 892 FGInterface::caught_wire_ft(double t, const double pt[4][3])
 893 {
 894   // Convert units and do the real work.
 895   SGVec3d pt_m[4];
 896   for (int i=0; i<4; ++i)
 897     pt_m[i] = SG_FEET_TO_METER*SGVec3d(pt[i]);
 898
 899   return ground_cache.caught_wire(t, pt_m);
 900 }
 901
 902 bool
 903 FGInterface::get_wire_ends_m(double t, double end[2][3], double vel[2][3])
 904 {
 905   SGVec3d _end[2], _vel[2];
 906   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 907   for (int k=0; k<2; ++k) {
 908     assign( end[k], _end[k] );
 909     assign( vel[k], _vel[k] );
 910   }
 911   return ret;
 912 }
 913
 914 bool
 915 FGInterface::get_wire_ends_ft(double t, double end[2][3], double vel[2][3])
 916 {
 917   // Convert units and do the real work.
 918   SGVec3d _end[2], _vel[2];
 919   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 920   for (int k=0; k<2; ++k) {
 921     assign( end[k], SG_METER_TO_FEET*_end[k] );
 922     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 923   }
 924   return ret;
 925 }
 926
 927 void
 928 FGInterface::release_wire(void)
 929 {
 930   ground_cache.release_wire();
 931 }
 932