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  - curt@infoplane.com
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 //
  21 // $Id$
  22
  23
  24 #include <stdio.h>
  25
  26 #include <plib/sg.h>
  27
  28 #include <simgear/constants.h>
  29 #include <simgear/debug/logstream.hxx>
  30 #include <simgear/math/sg_geodesy.hxx>
  31 #include <simgear/timing/timestamp.hxx>
  32
  33 #include <Scenery/scenery.hxx>
  34 #include <FDM/LaRCsim/ls_interface.h>
  35 #include <Main/globals.hxx>
  36 #include <Main/fg_props.hxx>
  37
  38 #include "External.hxx"
  39 #include "flight.hxx"
  40 #include "JSBSim.hxx"
  41 #include "LaRCsim.hxx"
  42 #include "Balloon.h"
  43
  44
  45 // base_fdm_state is the internal state that is updated in integer
  46 // multiples of "dt".  This leads to "jitter" with respect to the real
  47 // world time, so we introduce cur_fdm_state which is extrapolated by
  48 // the difference between sim time and real world time
  49
  50 FGInterface *cur_fdm_state;
  51 FGInterface base_fdm_state;
  52
  53 inline void init_vec(FG_VECTOR_3 vec) {
  54     vec[0] = 0.0; vec[1] = 0.0; vec[2] = 0.0;
  55 }
  56
  57 FGEngInterface::FGEngInterface() {
  58
  59     // inputs
  60     Throttle=0;
  61     Mixture=0;
  62     Prop_Advance=0;
  63
  64     // outputs
  65     RPM=0;
  66     Manifold_Pressure=0;
  67     MaxHP=0;
  68     Percentage_Power=0;
  69     EGT=0;
  70     prop_thrust=0;
  71 }
  72
  73 FGEngInterface::~FGEngInterface(void) {
  74 }
  75
  76 FGGearInterface::FGGearInterface(void) {
  77     x=y=z=0.0;
  78     brake=rolls=WoW=false;
  79     position=1.0;
  80 }
  81
  82 FGGearInterface::~FGGearInterface() {
  83 }
  84
  85 // Constructor
  86 FGInterface::FGInterface() {
  87     _setup();
  88 }
  89
  90 FGInterface::FGInterface( double dt ) {
  91     _setup();
  92     delta_t = dt;
  93     remainder = elapsed = multi_loop = 0;
  94 }
  95
  96 // Destructor
  97 FGInterface::~FGInterface() {
  98     // unbind();                   // FIXME: should be called explicitly
  99 }
 100
 101
 102 /**
 103  * Set default values for the state of the FDM.
 104  *
 105  * This method is invoked by the constructors.
 106  */
 107 void
 108 FGInterface::_setup ()
 109 {
 110     inited = false;
 111     bound = false;
 112
 113     init_vec( d_pilot_rp_body_v );
 114     init_vec( d_cg_rp_body_v );
 115     init_vec( f_body_total_v );
 116     init_vec( f_local_total_v );
 117     init_vec( f_aero_v );
 118     init_vec( f_engine_v );
 119     init_vec( f_gear_v );
 120     init_vec( m_total_rp_v );
 121     init_vec( m_total_cg_v );
 122     init_vec( m_aero_v );
 123     init_vec( m_engine_v );
 124     init_vec( m_gear_v );
 125     init_vec( v_dot_local_v );
 126     init_vec( v_dot_body_v );
 127     init_vec( a_cg_body_v );
 128     init_vec( a_pilot_body_v );
 129     init_vec( n_cg_body_v );
 130     init_vec( n_pilot_body_v );
 131     init_vec( omega_dot_body_v );
 132     init_vec( v_local_v );
 133     init_vec( v_local_rel_ground_v );
 134     init_vec( v_local_airmass_v );
 135     init_vec( v_local_rel_airmass_v );
 136     init_vec( v_local_gust_v );
 137     init_vec( v_wind_body_v );
 138     init_vec( omega_body_v );
 139     init_vec( omega_local_v );
 140     init_vec( omega_total_v );
 141     init_vec( euler_rates_v );
 142     init_vec( geocentric_rates_v );
 143     init_vec( geocentric_position_v );
 144     init_vec( geodetic_position_v );
 145     init_vec( euler_angles_v );
 146     init_vec( d_cg_rwy_local_v );
 147     init_vec( d_cg_rwy_rwy_v );
 148     init_vec( d_pilot_rwy_local_v );
 149     init_vec( d_pilot_rwy_rwy_v );
 150     init_vec( t_local_to_body_m[0] );
 151     init_vec( t_local_to_body_m[1] );
 152     init_vec( t_local_to_body_m[2] );
 153
 154     mass=i_xx=i_yy=i_zz=i_xz=0;
 155     nlf=0;
 156     v_rel_wind=v_true_kts=v_rel_ground=v_inertial=0;
 157     v_ground_speed=v_equiv=v_equiv_kts=0;
 158     v_calibrated=v_calibrated_kts=0;
 159     gravity=0;
 160     centrifugal_relief=0;
 161     alpha=beta=alpha_dot=beta_dot=0;
 162     cos_alpha=sin_alpha=cos_beta=sin_beta=0;
 163     cos_phi=sin_phi=cos_theta=sin_theta=cos_psi=sin_psi=0;
 164     gamma_vert_rad=gamma_horiz_rad=0;
 165     sigma=density=v_sound=mach_number=0;
 166     static_pressure=total_pressure=impact_pressure=0;
 167     dynamic_pressure=0;
 168     static_temperature=total_temperature=0;
 169     sea_level_radius=earth_position_angle=0;
 170     runway_altitude=runway_latitude=runway_longitude=0;
 171     runway_heading=0;
 172     radius_to_rwy=0;
 173     climb_rate=0;
 174     sin_lat_geocentric=cos_lat_geocentric=0;
 175     sin_latitude=cos_latitude=0;
 176     sin_longitude=cos_longitude=0;
 177     altitude_agl=0;
 178 }
 179
 180 void
 181 FGInterface::init () {}
 182
 183 /**
 184  * Initialize the state of the FDM.
 185  *
 186  * Subclasses of FGInterface may do their own, additional initialization,
 187  * but there is some that is common to all.  Normally, they should call
 188  * this before they begin their own init to make sure the basic structures
 189  * are set up properly.
 190  */
 191 void
 192 FGInterface::common_init ()
 193 {
 194     SG_LOG( SG_FLIGHT, SG_INFO, "Start common FDM init" );
 195
 196     set_inited( true );
 197
 198     stamp();
 199     set_remainder( 0 );
 200
 201     // Set initial position
 202     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing position..." );
 203     set_Longitude( fgGetDouble("/position/longitude-deg")
 204                    * SGD_DEGREES_TO_RADIANS );
 205     set_Latitude( fgGetDouble("/position/latitude-deg")
 206                   * SGD_DEGREES_TO_RADIANS );
 207     double ground_elev_m = scenery.get_cur_elev();
 208     double ground_elev_ft = ground_elev_m * SG_METER_TO_FEET;
 209     if ( fgGetBool("/sim/startup/onground")
 210          || fgGetDouble("/position/altitude-ft") < ground_elev_ft ) {
 211         fgSetDouble("/position/altitude-ft", ground_elev_ft);
 212     }
 213     set_Altitude( fgGetDouble("/position/altitude-ft") );
 214
 215     // Set ground elevation
 216     SG_LOG( SG_FLIGHT, SG_INFO,
 217             "...initializing ground elevation to " << ground_elev_ft
 218             << "ft..." );
 219     SG_LOG( SG_FLIGHT, SG_INFO, "common_init(): set ground elevation "
 220             << ground_elev_ft );
 221     base_fdm_state.set_Runway_altitude( ground_elev_ft );
 222     set_Runway_altitude( ground_elev_ft );
 223
 224     // Set sea-level radius
 225     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing sea-level radius..." );
 226     SG_LOG( SG_FLIGHT, SG_INFO, " lat = "
 227             << fgGetDouble("/position/latitude-deg")
 228             << " alt = " << fgGetDouble("/position/altitude-ft") );
 229     double sea_level_radius_meters;
 230     double lat_geoc;
 231     sgGeodToGeoc( fgGetDouble("/position/latitude-deg")
 232                     * SGD_DEGREES_TO_RADIANS,
 233                   fgGetDouble("/position/altitude-ft") * SG_FEET_TO_METER,
 234                   &sea_level_radius_meters, &lat_geoc );
 235     set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET );
 236
 237     // Set initial velocities
 238     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing velocities..." );
 239     if ( !fgHasNode("/sim/startup/speed-set") ) {
 240         set_V_calibrated_kts(0.0);
 241     } else {
 242         const string speedset = fgGetString("/sim/startup/speed-set");
 243         if ( speedset == "knots" || speedset == "KNOTS" ) {
 244             set_V_calibrated_kts( fgGetDouble("/velocities/airspeed-kt") );
 245         } else if ( speedset == "mach" || speedset == "MACH" ) {
 246             set_Mach_number( fgGetDouble("/velocities/mach") );
 247         } else if ( speedset == "UVW" || speedset == "uvw" ) {
 248             set_Velocities_Wind_Body(
 249                                      fgGetDouble("/velocities/uBody-fps"),
 250                                      fgGetDouble("/velocities/vBody-fps"),
 251                                      fgGetDouble("/velocities/wBody-fps") );
 252         } else if ( speedset == "NED" || speedset == "ned" ) {
 253             set_Velocities_Local(
 254                                  fgGetDouble("/velocities/speed-north-fps"),
 255                                  fgGetDouble("/velocities/speed-east-fps"),
 256                                  fgGetDouble("/velocities/speed-down-fps") );
 257         } else {
 258             SG_LOG( SG_FLIGHT, SG_ALERT,
 259                     "Unrecognized value for /sim/startup/speed-set: "
 260                     << speedset);
 261             set_V_calibrated_kts( 0.0 );
 262         }
 263     }
 264
 265     // Set initial Euler angles
 266     SG_LOG( SG_FLIGHT, SG_INFO, "...initializing Euler angles..." );
 267     set_Euler_Angles( fgGetDouble("/orientation/roll-deg")
 268                         * SGD_DEGREES_TO_RADIANS,
 269                       fgGetDouble("/orientation/pitch-deg")
 270                         * SGD_DEGREES_TO_RADIANS,
 271                       fgGetDouble("/orientation/heading-deg")
 272                         * SGD_DEGREES_TO_RADIANS );
 273
 274     SG_LOG( SG_FLIGHT, SG_INFO, "End common FDM init" );
 275 }
 276
 277
 278 /**
 279  * Bind getters and setters to properties.
 280  *
 281  * The bind() method will be invoked after init().  Note that unlike
 282  * the usual implementations of FGSubsystem::bind(), this method does
 283  * not automatically pick up existing values for the properties at
 284  * bind time; instead, all values are set explicitly in the init()
 285  * method.
 286  */
 287 void
 288 FGInterface::bind ()
 289 {
 290   bound = true;
 291
 292                                 // Time management (read-only)
 293   fgTie("/fdm/time/delta_t", this,
 294         &FGInterface::get_delta_t); // read-only
 295   fgTie("/fdm/time/elapsed", this,
 296         &FGInterface::get_elapsed); // read-only
 297   fgTie("/fdm/time/remainder", this,
 298         &FGInterface::get_remainder); // read-only
 299   fgTie("/fdm/time/multi_loop", this,
 300         &FGInterface::get_multi_loop); // read-only
 301
 302                         // Aircraft position
 303   fgTie("/position/latitude-deg", this,
 304         &FGInterface::get_Latitude_deg,
 305         &FGInterface::set_Latitude_deg,
 306         false);
 307   fgSetArchivable("/position/latitude-deg");
 308   fgTie("/position/longitude-deg", this,
 309         &FGInterface::get_Longitude_deg,
 310         &FGInterface::set_Longitude_deg,
 311         false);
 312   fgSetArchivable("/position/longitude-deg");
 313   fgTie("/position/altitude-ft", this,
 314         &FGInterface::get_Altitude,
 315         &FGInterface::set_Altitude,
 316         false);
 317   fgSetArchivable("/position/altitude-ft");
 318   fgTie("/position/altitude-agl-ft", this,
 319         &FGInterface::get_Altitude_AGL); // read-only
 320
 321                                 // Orientation
 322   fgTie("/orientation/roll-deg", this,
 323         &FGInterface::get_Phi_deg,
 324         &FGInterface::set_Phi_deg);
 325   fgSetArchivable("/orientation/roll-deg");
 326   fgTie("/orientation/pitch-deg", this,
 327         &FGInterface::get_Theta_deg,
 328         &FGInterface::set_Theta_deg);
 329   fgSetArchivable("/orientation/pitch-deg");
 330   fgTie("/orientation/heading-deg", this,
 331         &FGInterface::get_Psi_deg,
 332         &FGInterface::set_Psi_deg);
 333   fgSetArchivable("/orientation/heading-deg");
 334
 335                                 // Calibrated airspeed
 336   fgTie("/velocities/airspeed-kt", this,
 337         &FGInterface::get_V_calibrated_kts,
 338         &FGInterface::set_V_calibrated_kts,
 339         false);
 340
 341                                 // Local velocities
 342 //   fgTie("/velocities/speed-north-fps", this,
 343 //      &FGInterface::get_V_north,
 344 //      &FGInterface::set_V_north);
 345 //   fgSetArchivable("/velocities/speed-north-fps");
 346 //   fgTie("/velocities/speed-east-fps", this,
 347 //      &FGInterface::get_V_east,
 348 //      &FGInterface::set_V_east);
 349 //   fgSetArchivable("/velocities/speed-east-fps");
 350 //   fgTie("/velocities/speed-down-fps", this,
 351 //      &FGInterface::get_V_down,
 352 //      &FGInterface::set_V_down);
 353 //   fgSetArchivable("/velocities/speed-down-fps");
 354                                 // FIXME: Temporarily read-only, until the
 355                                 // incompatibilities between JSBSim and
 356                                 // LaRCSim are fixed (LaRCSim adds the
 357                                 // earth's rotation to the east velocity).
 358   fgTie("/velocities/speed-north-fps", this,
 359         &FGInterface::get_V_north);
 360   fgTie("/velocities/speed-east-fps", this,
 361         &FGInterface::get_V_east);
 362   fgTie("/velocities/speed-down-fps", this,
 363         &FGInterface::get_V_down);
 364
 365                                 // Relative wind
 366                                 // FIXME: temporarily archivable, until
 367                                 // the NED problem is fixed.
 368   fgTie("/velocities/uBody-fps", this,
 369         &FGInterface::get_uBody,
 370         &FGInterface::set_uBody,
 371         false);
 372   fgSetArchivable("/velocities/uBody-fps");
 373   fgTie("/velocities/vBody-fps", this,
 374         &FGInterface::get_vBody,
 375         &FGInterface::set_vBody,
 376         false);
 377   fgSetArchivable("/velocities/vBody-fps");
 378   fgTie("/velocities/wBody-fps", this,
 379         &FGInterface::get_wBody,
 380         &FGInterface::set_wBody,
 381         false);
 382   fgSetArchivable("/velocities/wBody-fps");
 383
 384                                 // Climb and slip (read-only)
 385   fgTie("/velocities/vertical-speed-fps", this,
 386         &FGInterface::get_Climb_Rate); // read-only
 387   fgTie("/velocities/side-slip-rad", this,
 388         &FGInterface::get_Beta); // read-only
 389
 390                                 // Powerplant
 391   for (int i = 0; i < get_num_engines(); i++) {
 392     char buf[64];
 393
 394     sprintf(buf, "/engines/engine[%d]/rpm", i);
 395     fgTie(buf, get_engine(i),
 396           &FGEngInterface::get_RPM, &FGEngInterface::set_RPM);
 397     fgSetArchivable(buf);
 398
 399     sprintf(buf, "/engines/engine[%d]/egt-degf", i);
 400     fgTie(buf, get_engine(i), &FGEngInterface::get_EGT);
 401
 402     sprintf(buf, "/engines/engine[%d]/cht-degf", i);
 403     fgTie(buf, get_engine(i), &FGEngInterface::get_CHT);
 404
 405     sprintf(buf, "/engines/engine[%d]/oil-temperature-degf", i);
 406     fgTie(buf, get_engine(i), &FGEngInterface::get_Oil_Temp);
 407
 408     sprintf(buf, "/engines/engine[%d]/mp-osi", i);
 409     fgTie(buf, get_engine(i), &FGEngInterface::get_Manifold_Pressure);
 410
 411     sprintf(buf, "/engines/engine[%d]/fuel-flow-gph", i);
 412     fgTie(buf, get_engine(i), &FGEngInterface::get_Fuel_Flow);
 413
 414     sprintf(buf, "/engines/engine[%d]/running", i);
 415     fgTie(buf, get_engine(i), &FGEngInterface::get_Running_Flag);
 416
 417     sprintf(buf, "/engines/engine[%d]/cranking", i);
 418     fgTie(buf, get_engine(i), &FGEngInterface::get_Cranking_Flag);
 419
 420   }
 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   bound = false;
 434
 435   fgUntie("/fdm/time/delta_t");
 436   fgUntie("/fdm/time/elapsed");
 437   fgUntie("/fdm/time/remainder");
 438   fgUntie("/fdm/time/multi_loop");
 439   fgUntie("/position/latitude-deg");
 440   fgUntie("/position/longitude-deg");
 441   fgUntie("/position/altitude-ft");
 442   fgUntie("/position/altitude-agl-ft");
 443   fgUntie("/orientation/heading-deg");
 444   fgUntie("/orientation/pitch-deg");
 445   fgUntie("/orientation/roll-deg");
 446   fgUntie("/velocities/airspeed-kt");
 447   fgUntie("/velocities/speed-north-fps");
 448   fgUntie("/velocities/speed-east-fps");
 449   fgUntie("/velocities/speed-down-fps");
 450   fgUntie("/velocities/uBody-fps");
 451   fgUntie("/velocities/vBody-fps");
 452   fgUntie("/velocities/wBody-fps");
 453   fgUntie("/velocities/vertical-speed-fps");
 454   fgUntie("/velocities/side-slip-rad");
 455   for (int i = 0; i < get_num_engines(); i++) {
 456     char buf[64];
 457     sprintf(buf, "/engines/engine[%d]/rpm", i);
 458     fgUntie(buf);
 459     sprintf(buf, "/engines/engine[%d]/egt-degf", i);
 460     fgUntie(buf);
 461     sprintf(buf, "/engines/engine[%d]/cht-degf", i);
 462     fgUntie(buf);
 463     sprintf(buf, "/engines/engine[%d]/oil-temperature-degf", i);
 464     fgUntie(buf);
 465     sprintf(buf, "/engines/engine[%d]/mp-osi", i);
 466     fgUntie(buf);
 467     sprintf(buf, "/engines/engine[%d]/fuel-flow-gph", i);
 468     fgUntie(buf);
 469     sprintf(buf, "/engines/engine[%d]/running", i);
 470     fgUntie(buf);
 471     sprintf(buf, "/engines/engine[%d]/cranking", i);
 472     fgUntie(buf);
 473   }
 474 }
 475
 476 void
 477 FGInterface::free_engines ()
 478 {
 479     int i;
 480     for ( i = 0; i < get_num_engines(); ++i ) {
 481         delete get_engine(i);
 482     }
 483     engines.clear();
 484 }
 485
 486 void
 487 FGInterface::free_gear_units ()
 488 {
 489     int i;
 490     for ( i = 0; i < get_num_gear(); ++i ) {
 491         delete [] get_gear_unit(i);
 492     }
 493     gear.clear();
 494 }
 495
 496 /**
 497  * Update the state of the FDM (i.e. run the equations of motion).
 498  */
 499 void
 500 FGInterface::update (int dt)
 501 {
 502     cout << "dummy update() ... SHOULDN'T BE CALLED!" << endl;
 503 }
 504
 505
 506 void FGInterface::_updateGeodeticPosition( double lat, double lon, double alt )
 507 {
 508     double lat_geoc, sl_radius;
 509
 510     // cout << "starting sea level rad = " << get_Sea_level_radius() << endl;
 511
 512     sgGeodToGeoc( lat, alt * SG_FEET_TO_METER, &sl_radius, &lat_geoc );
 513
 514     SG_LOG( SG_FLIGHT, SG_DEBUG, "lon = " << lon
 515             << " lat_geod = " << lat
 516             << " lat_geoc = " << lat_geoc
 517             << " alt = " << alt
 518             << " sl_radius = " << sl_radius * SG_METER_TO_FEET
 519             << " Equator = " << SG_EQUATORIAL_RADIUS_FT );
 520
 521     _set_Geocentric_Position( lat_geoc, lon,
 522                               sl_radius * SG_METER_TO_FEET + alt );
 523
 524     _set_Geodetic_Position( lat, lon, alt );
 525
 526     _set_Sea_level_radius( sl_radius * SG_METER_TO_FEET );
 527     _set_Runway_altitude( scenery.get_cur_elev() * SG_METER_TO_FEET );
 528
 529     _set_sin_lat_geocentric( lat_geoc );
 530     _set_cos_lat_geocentric( lat_geoc );
 531
 532     _set_sin_cos_longitude( lon );
 533
 534     _set_sin_cos_latitude( lat );
 535
 536     /* Norman's code for slope of the terrain */
 537     /* needs to be tested -- get it on the HUD and taxi around */
 538     /* double *tnorm = scenery.cur_normal;
 539
 540        double sy = sin ( -get_Psi() ) ;
 541        double cy = cos ( -get_Psi() ) ;
 542
 543        double phitb, thetatb, psitb;
 544        if ( tnorm[1] != 0.0 ) {
 545            psitb = -atan2 ( tnorm[0], tnorm[1] );
 546        }
 547        if ( tnorm[2] != 0.0 ) {
 548            thetatb =  atan2 ( tnorm[0] * cy - tnorm[1] * sy, tnorm[2] );
 549            phitb = -atan2 ( tnorm[1] * cy + tnorm[0] * sy, tnorm[2] );
 550        }
 551
 552        _set_terrain_slope(phitb, thetatb, psitb)
 553      */
 554 }
 555
 556
 557 void FGInterface::_updateGeocentricPosition( double lat_geoc, double lon,
 558                                              double alt )
 559 {
 560     double lat_geod, tmp_alt, sl_radius1, sl_radius2, tmp_lat_geoc;
 561
 562     // cout << "starting sea level rad = " << get_Sea_level_radius() << endl;
 563
 564     sgGeocToGeod( lat_geoc, ( get_Sea_level_radius() + alt ) * SG_FEET_TO_METER,
 565                   &lat_geod, &tmp_alt, &sl_radius1 );
 566     sgGeodToGeoc( lat_geod, alt * SG_FEET_TO_METER, &sl_radius2, &tmp_lat_geoc );
 567
 568     SG_LOG( SG_FLIGHT, SG_DEBUG, "lon = " << lon
 569             << " lat_geod = " << lat_geod
 570             << " lat_geoc = " << lat_geoc
 571             << " alt = " << alt
 572             << " tmp_alt = " << tmp_alt * SG_METER_TO_FEET
 573             << " sl_radius1 = " << sl_radius1 * SG_METER_TO_FEET
 574             << " sl_radius2 = " << sl_radius2 * SG_METER_TO_FEET
 575             << " Equator = " << SG_EQUATORIAL_RADIUS_FT );
 576
 577     _set_Geocentric_Position( lat_geoc, lon,
 578                               sl_radius2 * SG_METER_TO_FEET + alt );
 579
 580     _set_Geodetic_Position( lat_geod, lon, alt );
 581
 582     _set_Sea_level_radius( sl_radius2 * SG_METER_TO_FEET );
 583     _set_Runway_altitude( scenery.get_cur_elev() * SG_METER_TO_FEET );
 584
 585     _set_sin_lat_geocentric( lat_geoc );
 586     _set_cos_lat_geocentric( lat_geoc );
 587
 588     _set_sin_cos_longitude( lon );
 589
 590     _set_sin_cos_latitude( lat_geod );
 591
 592     /* Norman's code for slope of the terrain */
 593     /* needs to be tested -- get it on the HUD and taxi around */
 594     /* double *tnorm = scenery.cur_normal;
 595
 596        double sy = sin ( -get_Psi() ) ;
 597        double cy = cos ( -get_Psi() ) ;
 598
 599        double phitb, thetatb, psitb;
 600        if ( tnorm[1] != 0.0 ) {
 601            psitb = -atan2 ( tnorm[0], tnorm[1] );
 602        }
 603        if ( tnorm[2] != 0.0 ) {
 604            thetatb =  atan2 ( tnorm[0] * cy - tnorm[1] * sy, tnorm[2] );
 605            phitb = -atan2 ( tnorm[1] * cy + tnorm[0] * sy, tnorm[2] );
 606        }
 607
 608        _set_terrain_slope(phitb, thetatb, psitb)
 609      */
 610 }
 611
 612
 613 // Extrapolate fdm based on time_offset (in usec)
 614 void FGInterface::extrapolate( int time_offset ) {
 615     double dt = time_offset / 1000000.0;
 616
 617     // -dw- metrowerks complains about ambiguous access, not critical
 618     // to keep this ;)
 619 #ifndef __MWERKS__
 620     cout << "extrapolating FDM by dt = " << dt << endl;
 621 #endif
 622
 623     double lat = geodetic_position_v[0] + geocentric_rates_v[0] * dt;
 624     double lat_geoc = geocentric_position_v[0] + geocentric_rates_v[0] * dt;
 625
 626     double lon = geodetic_position_v[1] + geocentric_rates_v[1] * dt;
 627     double lon_geoc = geocentric_position_v[1] + geocentric_rates_v[1] * dt;
 628
 629     double alt = geodetic_position_v[2] + geocentric_rates_v[2] * dt;
 630     double radius = geocentric_position_v[2] + geocentric_rates_v[2] * dt;
 631
 632     geodetic_position_v[0] = lat;
 633     geocentric_position_v[0] = lat_geoc;
 634
 635     geodetic_position_v[1] = lon;
 636     geocentric_position_v[1] = lon_geoc;
 637
 638     geodetic_position_v[2] = alt;
 639     geocentric_position_v[2] = radius;
 640 }
 641
 642
 643 // Set the altitude (force)
 644 void fgFDMForceAltitude(const string &model, double alt_meters) {
 645     SG_LOG(SG_FLIGHT,SG_INFO, "fgFDMForceAltitude: " << alt_meters );
 646
 647     double sea_level_radius_meters;
 648     double lat_geoc;
 649
 650     // Set the FG variables first
 651     sgGeodToGeoc( base_fdm_state.get_Latitude(), alt_meters,
 652                   &sea_level_radius_meters, &lat_geoc);
 653
 654     base_fdm_state.set_Altitude( alt_meters * SG_METER_TO_FEET );
 655     base_fdm_state.set_Sea_level_radius( sea_level_radius_meters *
 656                                          SG_METER_TO_FEET );
 657
 658     cur_fdm_state->set_Altitude( alt_meters * SG_METER_TO_FEET );
 659     cur_fdm_state->set_Sea_level_radius( sea_level_radius_meters *
 660                                          SG_METER_TO_FEET );
 661
 662     // additional work needed for some flight models
 663     if ( model == "larcsim" ) {
 664         ls_ForceAltitude( base_fdm_state.get_Altitude() );
 665     }
 666 }
 667
 668
 669 // Positions
 670 void FGInterface::set_Latitude(double lat) {
 671     geodetic_position_v[0] = lat;
 672 }
 673
 674 void FGInterface::set_Longitude(double lon) {
 675     geodetic_position_v[1] = lon;
 676 }
 677
 678 void FGInterface::set_Altitude(double alt) {
 679     geodetic_position_v[2] = alt;
 680 }
 681
 682 void FGInterface::set_AltitudeAGL(double altagl) {
 683     altitude_agl=altagl;
 684 }
 685
 686 // Velocities
 687 void FGInterface::set_V_calibrated_kts(double vc) {
 688     v_calibrated_kts = vc;
 689 }
 690
 691 void FGInterface::set_Mach_number(double mach) {
 692     mach_number = mach;
 693 }
 694
 695 void FGInterface::set_Velocities_Local( double north,
 696                                         double east,
 697                                         double down ){
 698     v_local_v[0] = north;
 699     v_local_v[1] = east;
 700     v_local_v[2] = down;
 701 }
 702
 703 void FGInterface::set_Velocities_Wind_Body( double u,
 704                                             double v,
 705                                             double w){
 706     v_wind_body_v[0] = u;
 707     v_wind_body_v[1] = v;
 708     v_wind_body_v[2] = w;
 709 }
 710
 711 // Euler angles
 712 void FGInterface::set_Euler_Angles( double phi,
 713                                     double theta,
 714                                     double psi ) {
 715     euler_angles_v[0] = phi;
 716     euler_angles_v[1] = theta;
 717     euler_angles_v[2] = psi;
 718 }
 719
 720 // Flight Path
 721 void FGInterface::set_Climb_Rate( double roc) {
 722     climb_rate = roc;
 723 }
 724
 725 void FGInterface::set_Gamma_vert_rad( double gamma) {
 726     gamma_vert_rad = gamma;
 727 }
 728
 729 // Earth
 730 void FGInterface::set_Sea_level_radius(double slr) {
 731     sea_level_radius = slr;
 732 }
 733
 734 void FGInterface::set_Runway_altitude(double ralt) {
 735     runway_altitude = ralt;
 736 }
 737
 738 void FGInterface::set_Static_pressure(double p) { static_pressure = p; }
 739 void FGInterface::set_Static_temperature(double T) { static_temperature = T; }
 740 void FGInterface::set_Density(double rho) { density = rho; }
 741
 742 void FGInterface::set_Velocities_Local_Airmass (double wnorth,
 743                                                 double weast,
 744                                                 double wdown ) {
 745     v_local_airmass_v[0] = wnorth;
 746     v_local_airmass_v[1] = weast;
 747     v_local_airmass_v[2] = wdown;
 748 }
 749
 750
 751 void FGInterface::_busdump(void) {
 752
 753     SG_LOG(SG_FLIGHT,SG_INFO,"d_pilot_rp_body_v[3]: " << d_pilot_rp_body_v[0] << ", " << d_pilot_rp_body_v[1] << ", " << d_pilot_rp_body_v[2]);
 754     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rp_body_v[3]: " << d_cg_rp_body_v[0] << ", " << d_cg_rp_body_v[1] << ", " << d_cg_rp_body_v[2]);
 755     SG_LOG(SG_FLIGHT,SG_INFO,"f_body_total_v[3]: " << f_body_total_v[0] << ", " << f_body_total_v[1] << ", " << f_body_total_v[2]);
 756     SG_LOG(SG_FLIGHT,SG_INFO,"f_local_total_v[3]: " << f_local_total_v[0] << ", " << f_local_total_v[1] << ", " << f_local_total_v[2]);
 757     SG_LOG(SG_FLIGHT,SG_INFO,"f_aero_v[3]: " << f_aero_v[0] << ", " << f_aero_v[1] << ", " << f_aero_v[2]);
 758     SG_LOG(SG_FLIGHT,SG_INFO,"f_engine_v[3]: " << f_engine_v[0] << ", " << f_engine_v[1] << ", " << f_engine_v[2]);
 759     SG_LOG(SG_FLIGHT,SG_INFO,"f_gear_v[3]: " << f_gear_v[0] << ", " << f_gear_v[1] << ", " << f_gear_v[2]);
 760     SG_LOG(SG_FLIGHT,SG_INFO,"m_total_rp_v[3]: " << m_total_rp_v[0] << ", " << m_total_rp_v[1] << ", " << m_total_rp_v[2]);
 761     SG_LOG(SG_FLIGHT,SG_INFO,"m_total_cg_v[3]: " << m_total_cg_v[0] << ", " << m_total_cg_v[1] << ", " << m_total_cg_v[2]);
 762     SG_LOG(SG_FLIGHT,SG_INFO,"m_aero_v[3]: " << m_aero_v[0] << ", " << m_aero_v[1] << ", " << m_aero_v[2]);
 763     SG_LOG(SG_FLIGHT,SG_INFO,"m_engine_v[3]: " << m_engine_v[0] << ", " << m_engine_v[1] << ", " << m_engine_v[2]);
 764     SG_LOG(SG_FLIGHT,SG_INFO,"m_gear_v[3]: " << m_gear_v[0] << ", " << m_gear_v[1] << ", " << m_gear_v[2]);
 765     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_local_v[3]: " << v_dot_local_v[0] << ", " << v_dot_local_v[1] << ", " << v_dot_local_v[2]);
 766     SG_LOG(SG_FLIGHT,SG_INFO,"v_dot_body_v[3]: " << v_dot_body_v[0] << ", " << v_dot_body_v[1] << ", " << v_dot_body_v[2]);
 767     SG_LOG(SG_FLIGHT,SG_INFO,"a_cg_body_v[3]: " << a_cg_body_v[0] << ", " << a_cg_body_v[1] << ", " << a_cg_body_v[2]);
 768     SG_LOG(SG_FLIGHT,SG_INFO,"a_pilot_body_v[3]: " << a_pilot_body_v[0] << ", " << a_pilot_body_v[1] << ", " << a_pilot_body_v[2]);
 769     SG_LOG(SG_FLIGHT,SG_INFO,"n_cg_body_v[3]: " << n_cg_body_v[0] << ", " << n_cg_body_v[1] << ", " << n_cg_body_v[2]);
 770     SG_LOG(SG_FLIGHT,SG_INFO,"n_pilot_body_v[3]: " << n_pilot_body_v[0] << ", " << n_pilot_body_v[1] << ", " << n_pilot_body_v[2]);
 771     SG_LOG(SG_FLIGHT,SG_INFO,"omega_dot_body_v[3]: " << omega_dot_body_v[0] << ", " << omega_dot_body_v[1] << ", " << omega_dot_body_v[2]);
 772     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_v[3]: " << v_local_v[0] << ", " << v_local_v[1] << ", " << v_local_v[2]);
 773     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_ground_v[3]: " << v_local_rel_ground_v[0] << ", " << v_local_rel_ground_v[1] << ", " << v_local_rel_ground_v[2]);
 774     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_airmass_v[3]: " << v_local_airmass_v[0] << ", " << v_local_airmass_v[1] << ", " << v_local_airmass_v[2]);
 775     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_rel_airmass_v[3]: " << v_local_rel_airmass_v[0] << ", " << v_local_rel_airmass_v[1] << ", " << v_local_rel_airmass_v[2]);
 776     SG_LOG(SG_FLIGHT,SG_INFO,"v_local_gust_v[3]: " << v_local_gust_v[0] << ", " << v_local_gust_v[1] << ", " << v_local_gust_v[2]);
 777     SG_LOG(SG_FLIGHT,SG_INFO,"v_wind_body_v[3]: " << v_wind_body_v[0] << ", " << v_wind_body_v[1] << ", " << v_wind_body_v[2]);
 778     SG_LOG(SG_FLIGHT,SG_INFO,"omega_body_v[3]: " << omega_body_v[0] << ", " << omega_body_v[1] << ", " << omega_body_v[2]);
 779     SG_LOG(SG_FLIGHT,SG_INFO,"omega_local_v[3]: " << omega_local_v[0] << ", " << omega_local_v[1] << ", " << omega_local_v[2]);
 780     SG_LOG(SG_FLIGHT,SG_INFO,"omega_total_v[3]: " << omega_total_v[0] << ", " << omega_total_v[1] << ", " << omega_total_v[2]);
 781     SG_LOG(SG_FLIGHT,SG_INFO,"euler_rates_v[3]: " << euler_rates_v[0] << ", " << euler_rates_v[1] << ", " << euler_rates_v[2]);
 782     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_rates_v[3]: " << geocentric_rates_v[0] << ", " << geocentric_rates_v[1] << ", " << geocentric_rates_v[2]);
 783     SG_LOG(SG_FLIGHT,SG_INFO,"geocentric_position_v[3]: " << geocentric_position_v[0] << ", " << geocentric_position_v[1] << ", " << geocentric_position_v[2]);
 784     SG_LOG(SG_FLIGHT,SG_INFO,"geodetic_position_v[3]: " << geodetic_position_v[0] << ", " << geodetic_position_v[1] << ", " << geodetic_position_v[2]);
 785     SG_LOG(SG_FLIGHT,SG_INFO,"euler_angles_v[3]: " << euler_angles_v[0] << ", " << euler_angles_v[1] << ", " << euler_angles_v[2]);
 786     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rwy_local_v[3]: " << d_cg_rwy_local_v[0] << ", " << d_cg_rwy_local_v[1] << ", " << d_cg_rwy_local_v[2]);
 787     SG_LOG(SG_FLIGHT,SG_INFO,"d_cg_rwy_rwy_v[3]: " << d_cg_rwy_rwy_v[0] << ", " << d_cg_rwy_rwy_v[1] << ", " << d_cg_rwy_rwy_v[2]);
 788     SG_LOG(SG_FLIGHT,SG_INFO,"d_pilot_rwy_local_v[3]: " << d_pilot_rwy_local_v[0] << ", " << d_pilot_rwy_local_v[1] << ", " << d_pilot_rwy_local_v[2]);
 789     SG_LOG(SG_FLIGHT,SG_INFO,"d_pilot_rwy_rwy_v[3]: " << d_pilot_rwy_rwy_v[0] << ", " << d_pilot_rwy_rwy_v[1] << ", " << d_pilot_rwy_rwy_v[2]);
 790
 791     SG_LOG(SG_FLIGHT,SG_INFO,"t_local_to_body_m[0][3]: " << t_local_to_body_m[0][0] << ", " << t_local_to_body_m[0][1] << ", " << t_local_to_body_m[0][2]);
 792     SG_LOG(SG_FLIGHT,SG_INFO,"t_local_to_body_m[1][3]: " << t_local_to_body_m[1][0] << ", " << t_local_to_body_m[1][1] << ", " << t_local_to_body_m[1][2]);
 793     SG_LOG(SG_FLIGHT,SG_INFO,"t_local_to_body_m[2][3]: " << t_local_to_body_m[2][0] << ", " << t_local_to_body_m[2][1] << ", " << t_local_to_body_m[2][2]);
 794
 795     SG_LOG(SG_FLIGHT,SG_INFO,"mass: " << mass );
 796     SG_LOG(SG_FLIGHT,SG_INFO,"i_xx: " << i_xx );
 797     SG_LOG(SG_FLIGHT,SG_INFO,"i_yy: " << i_yy );
 798     SG_LOG(SG_FLIGHT,SG_INFO,"i_zz: " << i_zz );
 799     SG_LOG(SG_FLIGHT,SG_INFO,"i_xz: " << i_xz );
 800     SG_LOG(SG_FLIGHT,SG_INFO,"nlf: " << nlf );
 801     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_wind: " << v_rel_wind );
 802     SG_LOG(SG_FLIGHT,SG_INFO,"v_true_kts: " << v_true_kts );
 803     SG_LOG(SG_FLIGHT,SG_INFO,"v_rel_ground: " << v_rel_ground );
 804     SG_LOG(SG_FLIGHT,SG_INFO,"v_inertial: " << v_inertial );
 805     SG_LOG(SG_FLIGHT,SG_INFO,"v_ground_speed: " << v_ground_speed );
 806     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv: " << v_equiv );
 807     SG_LOG(SG_FLIGHT,SG_INFO,"v_equiv_kts: " << v_equiv_kts );
 808     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated: " << v_calibrated );
 809     SG_LOG(SG_FLIGHT,SG_INFO,"v_calibrated_kts: " << v_calibrated_kts );
 810     SG_LOG(SG_FLIGHT,SG_INFO,"gravity: " << gravity );
 811     SG_LOG(SG_FLIGHT,SG_INFO,"centrifugal_relief: " << centrifugal_relief );
 812     SG_LOG(SG_FLIGHT,SG_INFO,"alpha: " << alpha );
 813     SG_LOG(SG_FLIGHT,SG_INFO,"beta: " << beta );
 814     SG_LOG(SG_FLIGHT,SG_INFO,"alpha_dot: " << alpha_dot );
 815     SG_LOG(SG_FLIGHT,SG_INFO,"beta_dot: " << beta_dot );
 816     SG_LOG(SG_FLIGHT,SG_INFO,"cos_alpha: " << cos_alpha );
 817     SG_LOG(SG_FLIGHT,SG_INFO,"sin_alpha: " << sin_alpha );
 818     SG_LOG(SG_FLIGHT,SG_INFO,"cos_beta: " << cos_beta );
 819     SG_LOG(SG_FLIGHT,SG_INFO,"sin_beta: " << sin_beta );
 820     SG_LOG(SG_FLIGHT,SG_INFO,"cos_phi: " << cos_phi );
 821     SG_LOG(SG_FLIGHT,SG_INFO,"sin_phi: " << sin_phi );
 822     SG_LOG(SG_FLIGHT,SG_INFO,"cos_theta: " << cos_theta );
 823     SG_LOG(SG_FLIGHT,SG_INFO,"sin_theta: " << sin_theta );
 824     SG_LOG(SG_FLIGHT,SG_INFO,"cos_psi: " << cos_psi );
 825     SG_LOG(SG_FLIGHT,SG_INFO,"sin_psi: " << sin_psi );
 826     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_vert_rad: " << gamma_vert_rad );
 827     SG_LOG(SG_FLIGHT,SG_INFO,"gamma_horiz_rad: " << gamma_horiz_rad );
 828     SG_LOG(SG_FLIGHT,SG_INFO,"sigma: " << sigma );
 829     SG_LOG(SG_FLIGHT,SG_INFO,"density: " << density );
 830     SG_LOG(SG_FLIGHT,SG_INFO,"v_sound: " << v_sound );
 831     SG_LOG(SG_FLIGHT,SG_INFO,"mach_number: " << mach_number );
 832     SG_LOG(SG_FLIGHT,SG_INFO,"static_pressure: " << static_pressure );
 833     SG_LOG(SG_FLIGHT,SG_INFO,"total_pressure: " << total_pressure );
 834     SG_LOG(SG_FLIGHT,SG_INFO,"impact_pressure: " << impact_pressure );
 835     SG_LOG(SG_FLIGHT,SG_INFO,"dynamic_pressure: " << dynamic_pressure );
 836     SG_LOG(SG_FLIGHT,SG_INFO,"static_temperature: " << static_temperature );
 837     SG_LOG(SG_FLIGHT,SG_INFO,"total_temperature: " << total_temperature );
 838     SG_LOG(SG_FLIGHT,SG_INFO,"sea_level_radius: " << sea_level_radius );
 839     SG_LOG(SG_FLIGHT,SG_INFO,"earth_position_angle: " << earth_position_angle );
 840     SG_LOG(SG_FLIGHT,SG_INFO,"runway_altitude: " << runway_altitude );
 841     SG_LOG(SG_FLIGHT,SG_INFO,"runway_latitude: " << runway_latitude );
 842     SG_LOG(SG_FLIGHT,SG_INFO,"runway_longitude: " << runway_longitude );
 843     SG_LOG(SG_FLIGHT,SG_INFO,"runway_heading: " << runway_heading );
 844     SG_LOG(SG_FLIGHT,SG_INFO,"radius_to_rwy: " << radius_to_rwy );
 845     SG_LOG(SG_FLIGHT,SG_INFO,"climb_rate: " << climb_rate );
 846     SG_LOG(SG_FLIGHT,SG_INFO,"sin_lat_geocentric: " << sin_lat_geocentric );
 847     SG_LOG(SG_FLIGHT,SG_INFO,"cos_lat_geocentric: " << cos_lat_geocentric );
 848     SG_LOG(SG_FLIGHT,SG_INFO,"sin_longitude: " << sin_longitude );
 849     SG_LOG(SG_FLIGHT,SG_INFO,"cos_longitude: " << cos_longitude );
 850     SG_LOG(SG_FLIGHT,SG_INFO,"sin_latitude: " << sin_latitude );
 851     SG_LOG(SG_FLIGHT,SG_INFO,"cos_latitude: " << cos_latitude );
 852     SG_LOG(SG_FLIGHT,SG_INFO,"altitude_agl: " << altitude_agl );
 853 }
 854
 855
 856 void fgToggleFDMdataLogging(void) {
 857   cur_fdm_state->ToggleDataLogging();
 858 }