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 // base_fdm_state is the internal state that is updated in integer
  48 // multiples of "dt".  This leads to "jitter" with respect to the real
  49 // world time, so we introduce cur_fdm_state which is extrapolated by
  50 // the difference between sim time and real world time
  51
  52 FGInterface *cur_fdm_state = 0;
  53 FGInterface base_fdm_state;
  54
  55 // Constructor
  56 FGInterface::FGInterface()
  57   : remainder(0)
  58 {
  59     _setup();
  60 }
  61
  62 FGInterface::FGInterface( double dt )
  63   : remainder(0)
  64 {
  65     _setup();
  66 }
  67
  68 // Destructor
  69 FGInterface::~FGInterface() {
  70     // unbind();                   // FIXME: should be called explicitly
  71 }
  72
  73
  74 int
  75 FGInterface::_calc_multiloop (double dt)
  76 {
  77   int hz = fgGetInt("/sim/model-hz");
  78   int speedup = fgGetInt("/sim/speed-up");
  79
  80   dt += remainder;
  81   remainder = 0;
  82   double ml = dt * hz;
  83   // Avoid roundoff problems by adding the roundoff itself.
  84   // ... ok, two times the roundoff to have enough room.
  85   int multiloop = int(floor(ml * (1.0 + 2.0*DBL_EPSILON)));
  86   remainder = (ml - multiloop) / hz;
  87
  88   // If we artificially inflate ml above by a tiny amount to get the
  89   // closest integer, then subtract the integer from the original
  90   // slightly smaller value, we can get a negative remainder.
  91   // Logically this should never happen, and we definitely don't want
  92   // to carry a negative remainder over to the next iteration, so
  93   // never let the remainder go below zero.
  94   //
  95   // Note: this fixes a problem where we run 1, 3, 1, 3, 1, 3... loops
  96   // of the FDM when in fact we want to run 2, 2, 2, 2, 2...
  97   if ( remainder < 0 ) { remainder = 0; }
  98
  99   return (multiloop * speedup);
 100 }
 101
 102
 103 /**
 104  * Set default values for the state of the FDM.
 105  *
 106  * This method is invoked by the constructors.
 107  */
 108 void
 109 FGInterface::_setup ()
 110 {
 111     inited = false;
 112     bound = false;
 113
 114     d_cg_rp_body_v = SGVec3d::zeros();
 115     v_dot_local_v = SGVec3d::zeros();
 116     v_dot_body_v = SGVec3d::zeros();
 117     a_cg_body_v = SGVec3d::zeros();
 118     a_pilot_body_v = SGVec3d::zeros();
 119     n_cg_body_v = SGVec3d::zeros();
 120     v_local_v = SGVec3d::zeros();
 121     v_local_rel_ground_v = SGVec3d::zeros();
 122     v_local_airmass_v = SGVec3d::zeros();
 123     v_wind_body_v = SGVec3d::zeros();
 124     omega_body_v = SGVec3d::zeros();
 125     euler_rates_v = SGVec3d::zeros();
 126     geocentric_rates_v = SGVec3d::zeros();
 127     geodetic_position_v = SGGeod::fromRadM(0, 0, 0);
 128     cartesian_position_v = SGVec3d::fromGeod(geodetic_position_v);
 129     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 130     euler_angles_v = SGVec3d::zeros();
 131
 132     nlf=0;
 133     v_rel_wind=v_true_kts=0;
 134     v_ground_speed=v_equiv_kts=0;
 135     v_calibrated_kts=0;
 136     alpha=beta=0;
 137     gamma_vert_rad=0;
 138     density=mach_number=0;
 139     static_pressure=total_pressure=0;
 140     dynamic_pressure=0;
 141     static_temperature=total_temperature=0;
 142     sea_level_radius=earth_position_angle=0;
 143     runway_altitude=0;
 144     climb_rate=0;
 145     altitude_agl=0;
 146 }
 147
 148 void
 149 FGInterface::init () {}
 150
 151 /**
 152  * Initialize the state of the FDM.
 153  *
 154  * Subclasses of FGInterface may do their own, additional initialization,
 155  * but there is some that is common to all.  Normally, they should call
 156  * this before they begin their own init to make sure the basic structures
 157  * are set up properly.
 158  */
 159 void
 160 FGInterface::common_init ()
 161 {
 162     SG_LOG( SG_FLIGHT, SG_INFO, "Start common FDM init" );
 163
 164     set_inited( true );
 165
 166     ground_cache.set_cache_time_offset(globals->get_sim_time_sec());
 167
 168 //     stamp();
 169 //     set_remainder( 0 );
 170
 171     // Set initial position
 172     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing position..." );
 173     double lon = fgGetDouble("/sim/presets/longitude-deg")
 174       * SGD_DEGREES_TO_RADIANS;
 175     double lat = fgGetDouble("/sim/presets/latitude-deg")
 176       * SGD_DEGREES_TO_RADIANS;
 177     double alt_ft = fgGetDouble("/sim/presets/altitude-ft");
 178     double alt_m = alt_ft * SG_FEET_TO_METER;
 179     set_Longitude( lon );
 180     set_Latitude( lat );
 181     SG_LOG( SG_FLIGHT, SG_INFO, "Checking for lon = "
 182             << lon*SGD_RADIANS_TO_DEGREES << "deg, lat = "
 183             << lat*SGD_RADIANS_TO_DEGREES << "deg, alt = "
 184             << alt_ft << "ft");
 185
 186     double ground_elev_m = get_groundlevel_m(lat, lon, alt_m);
 187     double ground_elev_ft = ground_elev_m * SG_METER_TO_FEET;
 188     _set_Runway_altitude ( ground_elev_ft );
 189     if ( fgGetBool("/sim/presets/onground") || alt_ft < ground_elev_ft ) {
 190         fgSetDouble("/position/altitude-ft", ground_elev_ft + 0.1);
 191         set_Altitude( ground_elev_ft + 0.1);
 192     } else {
 193         set_Altitude( alt_ft );
 194     }
 195
 196     // Set ground elevation
 197     SG_LOG( SG_FLIGHT, SG_INFO,
 198             "...initializing ground elevation to " << ground_elev_ft
 199             << "ft..." );
 200
 201     // Set sea-level radius
 202     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing sea-level radius..." );
 203     SG_LOG( SG_FLIGHT, SG_INFO, " lat = "
 204             << fgGetDouble("/sim/presets/latitude-deg")
 205             << " alt = " << get_Altitude() );
 206     double slr = SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v);
 207     _set_Sea_level_radius( slr * SG_METER_TO_FEET );
 208
 209     // Set initial velocities
 210     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing velocities..." );
 211     if ( !fgHasNode("/sim/presets/speed-set") ) {
 212         set_V_calibrated_kts(0.0);
 213     } else {
 214         const string speedset = fgGetString("/sim/presets/speed-set");
 215         if ( speedset == "knots" || speedset == "KNOTS" ) {
 216             set_V_calibrated_kts( fgGetDouble("/sim/presets/airspeed-kt") );
 217         } else if ( speedset == "mach" || speedset == "MACH" ) {
 218             set_Mach_number( fgGetDouble("/sim/presets/mach") );
 219         } else if ( speedset == "UVW" || speedset == "uvw" ) {
 220             set_Velocities_Wind_Body(
 221                                      fgGetDouble("/sim/presets/uBody-fps"),
 222                                      fgGetDouble("/sim/presets/vBody-fps"),
 223                                      fgGetDouble("/sim/presets/wBody-fps") );
 224         } else if ( speedset == "NED" || speedset == "ned" ) {
 225             set_Velocities_Local(
 226                                  fgGetDouble("/sim/presets/speed-north-fps"),
 227                                  fgGetDouble("/sim/presets/speed-east-fps"),
 228                                  fgGetDouble("/sim/presets/speed-down-fps") );
 229         } else {
 230             SG_LOG( SG_FLIGHT, SG_ALERT,
 231                     "Unrecognized value for /sim/presets/speed-set: "
 232                     << speedset);
 233             set_V_calibrated_kts( 0.0 );
 234         }
 235     }
 236
 237     // Set initial Euler angles
 238     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing Euler angles..." );
 239     set_Euler_Angles( fgGetDouble("/sim/presets/roll-deg")
 240                         * SGD_DEGREES_TO_RADIANS,
 241                       fgGetDouble("/sim/presets/pitch-deg")
 242                         * SGD_DEGREES_TO_RADIANS,
 243                       fgGetDouble("/sim/presets/heading-deg")
 244                         * SGD_DEGREES_TO_RADIANS );
 245
 246     SG_LOG( SG_FLIGHT, SG_INFO, "End common FDM init" );
 247 }
 248
 249
 250 /**
 251  * Bind getters and setters to properties.
 252  *
 253  * The bind() method will be invoked after init().  Note that unlike
 254  * the usual implementations of FGSubsystem::bind(), this method does
 255  * not automatically pick up existing values for the properties at
 256  * bind time; instead, all values are set explicitly in the init()
 257  * method.
 258  */
 259 void
 260 FGInterface::bind ()
 261 {
 262   bound = true;
 263
 264                                 // Time management (read-only)
 265 //   fgTie("/fdm/time/delta_t", this,
 266 //         &FGInterface::get_delta_t); // read-only
 267 //   fgTie("/fdm/time/elapsed", this,
 268 //         &FGInterface::get_elapsed); // read-only
 269 //   fgTie("/fdm/time/remainder", this,
 270 //         &FGInterface::get_remainder); // read-only
 271 //   fgTie("/fdm/time/multi_loop", this,
 272 //         &FGInterface::get_multi_loop); // read-only
 273
 274                         // Aircraft position
 275   fgTie("/position/latitude-deg", this,
 276         &FGInterface::get_Latitude_deg,
 277         &FGInterface::set_Latitude_deg,
 278         false);
 279   fgSetArchivable("/position/latitude-deg");
 280   fgTie("/position/longitude-deg", this,
 281         &FGInterface::get_Longitude_deg,
 282         &FGInterface::set_Longitude_deg,
 283         false);
 284   fgSetArchivable("/position/longitude-deg");
 285   fgTie("/position/altitude-ft", this,
 286         &FGInterface::get_Altitude,
 287         &FGInterface::set_Altitude,
 288         false);
 289   fgSetArchivable("/position/altitude-ft");
 290   fgTie("/position/altitude-agl-ft", this,
 291         &FGInterface::get_Altitude_AGL); // read-only
 292   fgSetArchivable("/position/ground-elev-ft");
 293   fgTie("/position/ground-elev-ft", this,
 294         &FGInterface::get_Runway_altitude); // read-only
 295   fgSetArchivable("/position/ground-elev-m");
 296   fgTie("/position/ground-elev-m", this,
 297         &FGInterface::get_Runway_altitude_m); // read-only
 298   fgTie("/environment/ground-elevation-m", this,
 299         &FGInterface::get_Runway_altitude_m); // read-only
 300   fgSetArchivable("/position/sea-level-radius-ft");
 301   fgTie("/position/sea-level-radius-ft", this,
 302         &FGInterface::get_Sea_level_radius); // read-only
 303
 304                                 // Orientation
 305   fgTie("/orientation/roll-deg", this,
 306         &FGInterface::get_Phi_deg,
 307         &FGInterface::set_Phi_deg);
 308   fgSetArchivable("/orientation/roll-deg");
 309   fgTie("/orientation/pitch-deg", this,
 310         &FGInterface::get_Theta_deg,
 311         &FGInterface::set_Theta_deg);
 312   fgSetArchivable("/orientation/pitch-deg");
 313   fgTie("/orientation/heading-deg", this,
 314         &FGInterface::get_Psi_deg,
 315         &FGInterface::set_Psi_deg);
 316   fgSetArchivable("/orientation/heading-deg");
 317
 318   // Body-axis "euler rates" (rotation speed, but in a funny
 319   // representation).
 320   fgTie("/orientation/roll-rate-degps", this,
 321         &FGInterface::get_Phi_dot_degps);
 322   fgTie("/orientation/pitch-rate-degps", this,
 323         &FGInterface::get_Theta_dot_degps);
 324   fgTie("/orientation/yaw-rate-degps", this,
 325         &FGInterface::get_Psi_dot_degps);
 326
 327                                 // Ground speed knots
 328   fgTie("/velocities/groundspeed-kt", this,
 329         &FGInterface::get_V_ground_speed_kt);
 330
 331                                 // Calibrated airspeed
 332   fgTie("/velocities/airspeed-kt", this,
 333         &FGInterface::get_V_calibrated_kts,
 334         &FGInterface::set_V_calibrated_kts,
 335         false);
 336
 337                                 // Mach number
 338   fgTie("/velocities/mach", this,
 339         &FGInterface::get_Mach_number,
 340         &FGInterface::set_Mach_number,
 341         false);
 342
 343                                 // Local velocities
 344 //   fgTie("/velocities/speed-north-fps", this,
 345 //      &FGInterface::get_V_north,
 346 //      &FGInterface::set_V_north);
 347 //   fgSetArchivable("/velocities/speed-north-fps");
 348 //   fgTie("/velocities/speed-east-fps", this,
 349 //      &FGInterface::get_V_east,
 350 //      &FGInterface::set_V_east);
 351 //   fgSetArchivable("/velocities/speed-east-fps");
 352 //   fgTie("/velocities/speed-down-fps", this,
 353 //      &FGInterface::get_V_down,
 354 //      &FGInterface::set_V_down);
 355 //   fgSetArchivable("/velocities/speed-down-fps");
 356                                 // FIXME: Temporarily read-only, until the
 357                                 // incompatibilities between JSBSim and
 358                                 // LaRCSim are fixed (LaRCSim adds the
 359                                 // earth's rotation to the east velocity).
 360   fgTie("/velocities/speed-north-fps", this,
 361         &FGInterface::get_V_north);
 362   fgTie("/velocities/speed-east-fps", this,
 363         &FGInterface::get_V_east);
 364   fgTie("/velocities/speed-down-fps", this,
 365         &FGInterface::get_V_down);
 366
 367                                 // Relative wind
 368                                 // FIXME: temporarily archivable, until
 369                                 // the NED problem is fixed.
 370   fgTie("/velocities/uBody-fps", this,
 371         &FGInterface::get_uBody,
 372         &FGInterface::set_uBody,
 373         false);
 374   fgSetArchivable("/velocities/uBody-fps");
 375   fgTie("/velocities/vBody-fps", this,
 376         &FGInterface::get_vBody,
 377         &FGInterface::set_vBody,
 378         false);
 379   fgSetArchivable("/velocities/vBody-fps");
 380   fgTie("/velocities/wBody-fps", this,
 381         &FGInterface::get_wBody,
 382         &FGInterface::set_wBody,
 383         false);
 384   fgSetArchivable("/velocities/wBody-fps");
 385
 386                                 // Climb and slip (read-only)
 387   fgTie("/velocities/vertical-speed-fps", this,
 388         &FGInterface::get_Climb_Rate,
 389   &FGInterface::set_Climb_Rate );
 390   fgTie("/velocities/glideslope", this,
 391   &FGInterface::get_Gamma_vert_rad,
 392   &FGInterface::set_Gamma_vert_rad );
 393   fgTie("/orientation/side-slip-rad", this,
 394         &FGInterface::get_Beta); // read-only
 395   fgTie("/orientation/side-slip-deg", this,
 396   &FGInterface::get_Beta_deg); // read-only
 397   fgTie("/orientation/alpha-deg", this,
 398   &FGInterface::get_Alpha_deg); // read-only
 399   fgTie("/accelerations/nlf", this,
 400   &FGInterface::get_Nlf); // read-only
 401
 402                                 // NED accelerations
 403   fgTie("/accelerations/ned/north-accel-fps_sec",
 404         this, &FGInterface::get_V_dot_north);
 405   fgTie("/accelerations/ned/east-accel-fps_sec",
 406         this, &FGInterface::get_V_dot_east);
 407   fgTie("/accelerations/ned/down-accel-fps_sec",
 408         this, &FGInterface::get_V_dot_down);
 409
 410                                 // Pilot accelerations
 411   fgTie("/accelerations/pilot/x-accel-fps_sec",
 412         this, &FGInterface::get_A_X_pilot);
 413   fgTie("/accelerations/pilot/y-accel-fps_sec",
 414         this, &FGInterface::get_A_Y_pilot);
 415   fgTie("/accelerations/pilot/z-accel-fps_sec",
 416         this, &FGInterface::get_A_Z_pilot);
 417
 418 }
 419
 420
 421 /**
 422  * Unbind any properties bound to this FDM.
 423  *
 424  * This method allows the FDM to release properties so that a new
 425  * FDM can bind them instead.
 426  */
 427 void
 428 FGInterface::unbind ()
 429 {
 430   bound = false;
 431
 432   // fgUntie("/fdm/time/delta_t");
 433   // fgUntie("/fdm/time/elapsed");
 434   // fgUntie("/fdm/time/remainder");
 435   // fgUntie("/fdm/time/multi_loop");
 436   fgUntie("/position/latitude-deg");
 437   fgUntie("/position/longitude-deg");
 438   fgUntie("/position/altitude-ft");
 439   fgUntie("/position/altitude-agl-ft");
 440   fgUntie("/position/ground-elev-ft");
 441   fgUntie("/position/ground-elev-m");
 442   fgUntie("/environment/ground-elevation-m");
 443   fgUntie("/position/sea-level-radius-ft");
 444   fgUntie("/orientation/roll-deg");
 445   fgUntie("/orientation/pitch-deg");
 446   fgUntie("/orientation/heading-deg");
 447   fgUntie("/orientation/roll-rate-degps");
 448   fgUntie("/orientation/pitch-rate-degps");
 449   fgUntie("/orientation/yaw-rate-degps");
 450   fgUntie("/orientation/side-slip-rad");
 451   fgUntie("/orientation/side-slip-deg");
 452   fgUntie("/orientation/alpha-deg");
 453   fgUntie("/velocities/airspeed-kt");
 454   fgUntie("/velocities/groundspeed-kt");
 455   fgUntie("/velocities/mach");
 456   fgUntie("/velocities/speed-north-fps");
 457   fgUntie("/velocities/speed-east-fps");
 458   fgUntie("/velocities/speed-down-fps");
 459   fgUntie("/velocities/uBody-fps");
 460   fgUntie("/velocities/vBody-fps");
 461   fgUntie("/velocities/wBody-fps");
 462   fgUntie("/velocities/vertical-speed-fps");
 463   fgUntie("/velocities/glideslope");
 464   fgUntie("/accelerations/nlf");
 465   fgUntie("/accelerations/pilot/x-accel-fps_sec");
 466   fgUntie("/accelerations/pilot/y-accel-fps_sec");
 467   fgUntie("/accelerations/pilot/z-accel-fps_sec");
 468   fgUntie("/accelerations/ned/north-accel-fps_sec");
 469   fgUntie("/accelerations/ned/east-accel-fps_sec");
 470   fgUntie("/accelerations/ned/down-accel-fps_sec");
 471 }
 472
 473 /**
 474  * Update the state of the FDM (i.e. run the equations of motion).
 475  */
 476 void
 477 FGInterface::update (double dt)
 478 {
 479     SG_LOG(SG_FLIGHT, SG_ALERT, "dummy update() ... SHOULDN'T BE CALLED!");
 480 }
 481
 482
 483 void FGInterface::_updatePositionM(const SGVec3d& cartPos)
 484 {
 485     cartesian_position_v = cartPos;
 486     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 487     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 488     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(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     geodetic_position_v = geod;
 496     cartesian_position_v = SGVec3d::fromGeod(geodetic_position_v);
 497     geocentric_position_v = SGGeoc::fromCart(cartesian_position_v);
 498
 499     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 500     _update_ground_elev_at_pos();
 501 }
 502
 503
 504 void FGInterface::_updatePosition(const SGGeoc& geoc)
 505 {
 506     geocentric_position_v = geoc;
 507     cartesian_position_v = SGVec3d::fromGeoc(geocentric_position_v);
 508     geodetic_position_v = SGGeod::fromCart(cartesian_position_v);
 509
 510     _set_Sea_level_radius( SGGeodesy::SGGeodToSeaLevelRadius(geodetic_position_v)*SG_METER_TO_FEET );
 511     _update_ground_elev_at_pos();
 512 }
 513
 514
 515 void FGInterface::_updateGeodeticPosition( double lat, double lon, double alt )
 516 {
 517     _updatePosition(SGGeod::fromRadFt(lon, lat, alt));
 518 }
 519
 520
 521 void FGInterface::_updateGeocentricPosition( double lat, double lon,
 522                                              double alt )
 523 {
 524     _updatePosition(SGGeoc::fromRadFt(lon, lat, get_Sea_level_radius() + alt));
 525 }
 526
 527 void FGInterface::_update_ground_elev_at_pos( void ) {
 528     double groundlevel_m = get_groundlevel_m(geodetic_position_v);
 529     _set_Runway_altitude( groundlevel_m * SG_METER_TO_FEET );
 530 }
 531
 532 // Positions
 533 void FGInterface::set_Latitude(double lat) {
 534     geodetic_position_v.setLatitudeRad(lat);
 535 }
 536
 537 void FGInterface::set_Longitude(double lon) {
 538     geodetic_position_v.setLongitudeRad(lon);
 539 }
 540
 541 void FGInterface::set_Altitude(double alt) {
 542     geodetic_position_v.setElevationFt(alt);
 543 }
 544
 545 void FGInterface::set_AltitudeAGL(double altagl) {
 546     altitude_agl=altagl;
 547 }
 548
 549 // Velocities
 550 void FGInterface::set_V_calibrated_kts(double vc) {
 551     v_calibrated_kts = vc;
 552 }
 553
 554 void FGInterface::set_Mach_number(double mach) {
 555     mach_number = mach;
 556 }
 557
 558 void FGInterface::set_Velocities_Local( double north,
 559                                         double east,
 560                                         double down ){
 561     v_local_v[0] = north;
 562     v_local_v[1] = east;
 563     v_local_v[2] = down;
 564 }
 565
 566 void FGInterface::set_Velocities_Wind_Body( double u,
 567                                             double v,
 568                                             double w){
 569     v_wind_body_v[0] = u;
 570     v_wind_body_v[1] = v;
 571     v_wind_body_v[2] = w;
 572 }
 573
 574 // Euler angles
 575 void FGInterface::set_Euler_Angles( double phi,
 576                                     double theta,
 577                                     double psi ) {
 578     euler_angles_v[0] = phi;
 579     euler_angles_v[1] = theta;
 580     euler_angles_v[2] = psi;
 581 }
 582
 583 // Flight Path
 584 void FGInterface::set_Climb_Rate( double roc) {
 585     climb_rate = roc;
 586 }
 587
 588 void FGInterface::set_Gamma_vert_rad( double gamma) {
 589     gamma_vert_rad = gamma;
 590 }
 591
 592 void FGInterface::set_Static_pressure(double p) { static_pressure = p; }
 593 void FGInterface::set_Static_temperature(double T) { static_temperature = T; }
 594 void FGInterface::set_Density(double rho) { density = rho; }
 595
 596 void FGInterface::set_Velocities_Local_Airmass (double wnorth,
 597                                                 double weast,
 598                                                 double wdown ) {
 599     v_local_airmass_v[0] = wnorth;
 600     v_local_airmass_v[1] = weast;
 601     v_local_airmass_v[2] = wdown;
 602 }
 603
 604
 605 void FGInterface::_busdump(void) {
 606
 607     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rp_body_v: " << d_cg_rp_body_v);
 608     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_local_v: " << v_dot_local_v);
 609     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_body_v: " << v_dot_body_v);
 610     SG_LOG(SG_FLIGHT,SG_INFO,"a_cg_body_v: " << a_cg_body_v);
 611     SG_LOG(SG_FLIGHT,SG_INFO,"a_pilot_body_v: " << a_pilot_body_v);
 612     SG_LOG(SG_FLIGHT,SG_INFO,"n_cg_body_v: " << n_cg_body_v);
 613     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_v: " << v_local_v);
 614     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_ground_v: " << v_local_rel_ground_v);
 615     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_airmass_v: " << v_local_airmass_v);
 616     SG_LOG(SG_FLIGHT,SG_INFO,"v_wind_body_v: " << v_wind_body_v);
 617     SG_LOG(SG_FLIGHT,SG_INFO,"omega_body_v: " << omega_body_v);
 618     SG_LOG(SG_FLIGHT,SG_INFO,"euler_rates_v: " << euler_rates_v);
 619     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_rates_v: " << geocentric_rates_v);
 620     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_position_v: " << geocentric_position_v);
 621     SG_LOG(SG_FLIGHT,SG_INFO,"geodetic_position_v: " << geodetic_position_v);
 622     SG_LOG(SG_FLIGHT,SG_INFO,"euler_angles_v: " << euler_angles_v);
 623
 624     SG_LOG(SG_FLIGHT,SG_INFO,"nlf: " << nlf );
 625     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_wind: " << v_rel_wind );
 626     SG_LOG(SG_FLIGHT,SG_INFO,"v_true_kts: " << v_true_kts );
 627     SG_LOG(SG_FLIGHT,SG_INFO,"v_ground_speed: " << v_ground_speed );
 628     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv_kts: " << v_equiv_kts );
 629     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated_kts: " << v_calibrated_kts );
 630     SG_LOG(SG_FLIGHT,SG_INFO,"alpha: " << alpha );
 631     SG_LOG(SG_FLIGHT,SG_INFO,"beta: " << beta );
 632     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_vert_rad: " << gamma_vert_rad );
 633     SG_LOG(SG_FLIGHT,SG_INFO,"density: " << density );
 634     SG_LOG(SG_FLIGHT,SG_INFO,"mach_number: " << mach_number );
 635     SG_LOG(SG_FLIGHT,SG_INFO,"static_pressure: " << static_pressure );
 636     SG_LOG(SG_FLIGHT,SG_INFO,"total_pressure: " << total_pressure );
 637     SG_LOG(SG_FLIGHT,SG_INFO,"dynamic_pressure: " << dynamic_pressure );
 638     SG_LOG(SG_FLIGHT,SG_INFO,"static_temperature: " << static_temperature );
 639     SG_LOG(SG_FLIGHT,SG_INFO,"total_temperature: " << total_temperature );
 640     SG_LOG(SG_FLIGHT,SG_INFO,"sea_level_radius: " << sea_level_radius );
 641     SG_LOG(SG_FLIGHT,SG_INFO,"earth_position_angle: " << earth_position_angle );
 642     SG_LOG(SG_FLIGHT,SG_INFO,"runway_altitude: " << runway_altitude );
 643     SG_LOG(SG_FLIGHT,SG_INFO,"climb_rate: " << climb_rate );
 644     SG_LOG(SG_FLIGHT,SG_INFO,"altitude_agl: " << altitude_agl );
 645 }
 646
 647 bool
 648 FGInterface::prepare_ground_cache_m(double startSimTime, double endSimTime,
 649                                     const double pt[3], double rad)
 650 {
 651   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 652                                            SGVec3d(pt), rad);
 653 }
 654
 655 bool
 656 FGInterface::prepare_ground_cache_ft(double startSimTime, double endSimTime,
 657                                      const double pt[3], double rad)
 658 {
 659   // Convert units and do the real work.
 660   SGVec3d pt_ft = SG_FEET_TO_METER*SGVec3d(pt);
 661   return ground_cache.prepare_ground_cache(startSimTime, endSimTime,
 662                                            pt_ft, rad*SG_FEET_TO_METER);
 663 }
 664
 665 bool
 666 FGInterface::is_valid_m(double *ref_time, double pt[3], double *rad)
 667 {
 668   SGVec3d _pt;
 669   bool valid = ground_cache.is_valid(*ref_time, _pt, *rad);
 670   assign(pt, _pt);
 671   return valid;
 672 }
 673
 674 bool FGInterface::is_valid_ft(double *ref_time, double pt[3], double *rad)
 675 {
 676   // Convert units and do the real work.
 677   SGVec3d _pt;
 678   bool found_ground = ground_cache.is_valid(*ref_time, _pt, *rad);
 679   assign(pt, SG_METER_TO_FEET*_pt);
 680   *rad *= SG_METER_TO_FEET;
 681   return found_ground;
 682 }
 683
 684 double
 685 FGInterface::get_cat_m(double t, const double pt[3],
 686                        double end[2][3], double vel[2][3])
 687 {
 688   SGVec3d _end[2], _vel[2];
 689   double dist = ground_cache.get_cat(t, SGVec3d(pt), _end, _vel);
 690   for (int k=0; k<2; ++k) {
 691     assign( end[k], _end[k] );
 692     assign( vel[k], _vel[k] );
 693   }
 694   return dist;
 695 }
 696
 697 double
 698 FGInterface::get_cat_ft(double t, const double pt[3],
 699                         double end[2][3], double vel[2][3])
 700 {
 701   // Convert units and do the real work.
 702   SGVec3d pt_m = SG_FEET_TO_METER*SGVec3d(pt);
 703   SGVec3d _end[2], _vel[2];
 704   double dist = ground_cache.get_cat(t, pt_m, _end, _vel);
 705   for (int k=0; k<2; ++k) {
 706     assign( end[k], SG_METER_TO_FEET*_end[k] );
 707     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 708   }
 709   return dist*SG_METER_TO_FEET;
 710 }
 711
 712 bool
 713 FGInterface::get_body_m(double t, simgear::BVHNode::Id id,
 714                         double bodyToWorld[16], double linearVel[3],
 715                         double angularVel[3])
 716 {
 717   SGMatrixd _bodyToWorld;
 718   SGVec3d _linearVel, _angularVel;
 719   if (!ground_cache.get_body(t, _bodyToWorld, _linearVel, _angularVel, id))
 720     return false;
 721
 722   assign(linearVel, _linearVel);
 723   assign(angularVel, _angularVel);
 724   for (unsigned i = 0; i < 16; ++i)
 725       bodyToWorld[i] = _bodyToWorld.data()[i];
 726
 727   return true;
 728 }
 729
 730 bool
 731 FGInterface::get_agl_m(double t, const double pt[3], double max_altoff,
 732                        double contact[3], double normal[3],
 733                        double linearVel[3], double angularVel[3],
 734                        SGMaterial const*& material, simgear::BVHNode::Id& id)
 735 {
 736   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 737   SGVec3d _contact, _normal, _linearVel, _angularVel;
 738   material = 0;
 739   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 740                                   _angularVel, id, material);
 741   // correct the linear velocity, since the line intersector delivers
 742   // values for the start point and the get_agl function should
 743   // traditionally deliver for the contact point
 744   _linearVel += cross(_angularVel, _contact - pt_m);
 745
 746   assign(contact, _contact);
 747   assign(normal, _normal);
 748   assign(linearVel, _linearVel);
 749   assign(angularVel, _angularVel);
 750   return ret;
 751 }
 752
 753 bool
 754 FGInterface::get_agl_ft(double t, const double pt[3], double max_altoff,
 755                         double contact[3], double normal[3],
 756                         double linearVel[3], double angularVel[3],
 757                         SGMaterial const*& material, simgear::BVHNode::Id& id)
 758 {
 759   // Convert units and do the real work.
 760   SGVec3d pt_m = SGVec3d(pt) - max_altoff*ground_cache.get_down();
 761   pt_m *= SG_FEET_TO_METER;
 762   SGVec3d _contact, _normal, _linearVel, _angularVel;
 763   material = 0;
 764   bool ret = ground_cache.get_agl(t, pt_m, _contact, _normal, _linearVel,
 765                                   _angularVel, id, material);
 766   // correct the linear velocity, since the line intersector delivers
 767   // values for the start point and the get_agl function should
 768   // traditionally deliver for the contact point
 769   _linearVel += cross(_angularVel, _contact - pt_m);
 770
 771   // Convert units back ...
 772   assign( contact, SG_METER_TO_FEET*_contact );
 773   assign( normal, _normal );
 774   assign( linearVel, SG_METER_TO_FEET*_linearVel );
 775   assign( angularVel, _angularVel );
 776   return ret;
 777 }
 778
 779 bool
 780 FGInterface::get_nearest_m(double t, const double pt[3], double maxDist,
 781                            double contact[3], double normal[3],
 782                            double linearVel[3], double angularVel[3],
 783                            SGMaterial const*& material,
 784                            simgear::BVHNode::Id& id)
 785 {
 786   SGVec3d _contact, _linearVel, _angularVel;
 787   if (!ground_cache.get_nearest(t, SGVec3d(pt), maxDist, _contact, _linearVel,
 788                                 _angularVel, id, material))
 789       return false;
 790
 791   assign(contact, _contact);
 792   assign(linearVel, _linearVel);
 793   assign(angularVel, _angularVel);
 794   return true;
 795 }
 796
 797 bool
 798 FGInterface::get_nearest_ft(double t, const double pt[3], double maxDist,
 799                             double contact[3], double normal[3],
 800                             double linearVel[3], double angularVel[3],
 801                             SGMaterial const*& material,
 802                             simgear::BVHNode::Id& id)
 803 {
 804   SGVec3d _contact, _linearVel, _angularVel;
 805   if (!ground_cache.get_nearest(t, SG_FEET_TO_METER*SGVec3d(pt),
 806                                 SG_FEET_TO_METER*maxDist, _contact, _linearVel,
 807                                 _angularVel, id, material))
 808       return false;
 809
 810   assign(contact, SG_METER_TO_FEET*_contact);
 811   assign(linearVel, SG_METER_TO_FEET*_linearVel);
 812   assign(angularVel, _angularVel);
 813   return true;
 814 }
 815
 816 double
 817 FGInterface::get_groundlevel_m(double lat, double lon, double alt)
 818 {
 819   return get_groundlevel_m(SGGeod::fromRadM(lon, lat, alt));
 820 }
 821
 822 double
 823 FGInterface::get_groundlevel_m(const SGGeod& geod)
 824 {
 825   // Compute the cartesian position of the given lat/lon/alt.
 826   SGVec3d pos = SGVec3d::fromGeod(geod);
 827
 828   // FIXME: how to handle t - ref_time differences ???
 829   SGVec3d cpos;
 830   double ref_time = 0, radius;
 831   // Prepare the ground cache for that position.
 832   if (!is_valid_m(&ref_time, cpos.data(), &radius)) {
 833     double startTime = ref_time;
 834     double endTime = startTime + 1;
 835     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), 10);
 836     /// This is most likely the case when the given altitude is
 837     /// too low, try with a new altitude of 10000m, that should be
 838     /// sufficient to find a ground level below everywhere on our planet
 839     if (!ok) {
 840       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 841       /// If there is still no ground, return sea level radius
 842       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), 10))
 843         return 0;
 844     }
 845   } else if (radius*radius <= distSqr(pos, cpos)) {
 846     double startTime = ref_time;
 847     double endTime = startTime + 1;
 848
 849     /// We reuse the old radius value, but only if it is at least 10 Meters ..
 850     if (!(10 < radius)) // Well this strange compare is nan safe
 851       radius = 10;
 852
 853     bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), radius);
 854     /// This is most likely the case when the given altitude is
 855     /// too low, try with a new altitude of 10000m, that should be
 856     /// sufficient to find a ground level below everywhere on our planet
 857     if (!ok) {
 858       pos = SGVec3d::fromGeod(SGGeod::fromGeodM(geod, 10000));
 859       /// If there is still no ground, return sea level radius
 860       if (!prepare_ground_cache_m(startTime, endTime, pos.data(), radius))
 861         return 0;
 862     }
 863   }
 864
 865   double contact[3], normal[3], vel[3], angvel[3];
 866   const SGMaterial* material;
 867   simgear::BVHNode::Id id;
 868   // Ignore the return value here, since it just tells us if
 869   // the returns stem from the groundcache or from the coarse
 870   // computations below the groundcache. The contact point is still something
 871   // valid, the normals and the other returns just contain some defaults.
 872   get_agl_m(ref_time, pos.data(), 2.0, contact, normal, vel, angvel,
 873             material, id);
 874   return SGGeod::fromCart(SGVec3d(contact)).getElevationM();
 875 }
 876
 877 bool
 878 FGInterface::caught_wire_m(double t, const double pt[4][3])
 879 {
 880   SGVec3d pt_m[4];
 881   for (int i=0; i<4; ++i)
 882     pt_m[i] = SGVec3d(pt[i]);
 883
 884   return ground_cache.caught_wire(t, pt_m);
 885 }
 886
 887 bool
 888 FGInterface::caught_wire_ft(double t, const double pt[4][3])
 889 {
 890   // Convert units and do the real work.
 891   SGVec3d pt_m[4];
 892   for (int i=0; i<4; ++i)
 893     pt_m[i] = SG_FEET_TO_METER*SGVec3d(pt[i]);
 894
 895   return ground_cache.caught_wire(t, pt_m);
 896 }
 897
 898 bool
 899 FGInterface::get_wire_ends_m(double t, double end[2][3], double vel[2][3])
 900 {
 901   SGVec3d _end[2], _vel[2];
 902   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 903   for (int k=0; k<2; ++k) {
 904     assign( end[k], _end[k] );
 905     assign( vel[k], _vel[k] );
 906   }
 907   return ret;
 908 }
 909
 910 bool
 911 FGInterface::get_wire_ends_ft(double t, double end[2][3], double vel[2][3])
 912 {
 913   // Convert units and do the real work.
 914   SGVec3d _end[2], _vel[2];
 915   bool ret = ground_cache.get_wire_ends(t, _end, _vel);
 916   for (int k=0; k<2; ++k) {
 917     assign( end[k], SG_METER_TO_FEET*_end[k] );
 918     assign( vel[k], SG_METER_TO_FEET*_vel[k] );
 919   }
 920   return ret;
 921 }
 922
 923 void
 924 FGInterface::release_wire(void)
 925 {
 926   ground_cache.release_wire();
 927 }
 928
 929 void fgToggleFDMdataLogging(void) {
 930   cur_fdm_state->ToggleDataLogging();
 931 }