src/Network/native_fdm.cxx

   1 // native_fdm.cxx -- FGFS "Native" flight dynamics protocal class
   2 //
   3 // Written by Curtis Olson, started September 2001.
   4 //
   5 // Copyright (C) 2001  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
  24 #ifdef HAVE_CONFIG_H
  25 #  include <config.h>
  26 #endif
  27
  28 #include <simgear/debug/logstream.hxx>
  29 #include <simgear/io/lowlevel.hxx> // endian tests
  30 #include <simgear/io/iochannel.hxx>
  31 #include <simgear/timing/sg_time.hxx>
  32
  33 #include <FDM/flight.hxx>
  34 #include <Time/tmp.hxx>
  35 #include <Main/fg_props.hxx>
  36 #include <Main/globals.hxx>
  37 #include <Scenery/scenery.hxx>
  38
  39 #include "native_fdm.hxx"
  40
  41 // FreeBSD works better with this included last ... (?)
  42 #if defined( _MSC_VER )
  43 #  include <windows.h>
  44 #elif defined( __MINGW32__ )
  45 #  include <winsock2.h>
  46 #else
  47 #  include <netinet/in.h>       // htonl() ntohl()
  48 #endif
  49
  50
  51 // The function htond is defined this way due to the way some
  52 // processors and OSes treat floating point values.  Some will raise
  53 // an exception whenever a "bad" floating point value is loaded into a
  54 // floating point register.  Solaris is notorious for this, but then
  55 // so is LynxOS on the PowerPC.  By translating the data in place,
  56 // there is no need to load a FP register with the "corruped" floating
  57 // point value.  By doing the BIG_ENDIAN test, I can optimize the
  58 // routine for big-endian processors so it can be as efficient as
  59 // possible
  60 static void htond (double &x)
  61 {
  62     if ( sgIsLittleEndian() ) {
  63         int    *Double_Overlay;
  64         int     Holding_Buffer;
  65
  66         Double_Overlay = (int *) &x;
  67         Holding_Buffer = Double_Overlay [0];
  68
  69         Double_Overlay [0] = htonl (Double_Overlay [1]);
  70         Double_Overlay [1] = htonl (Holding_Buffer);
  71     } else {
  72         return;
  73     }
  74 }
  75
  76 // Float version
  77 static void htonf (float &x)
  78 {
  79     if ( sgIsLittleEndian() ) {
  80         int    *Float_Overlay;
  81         int     Holding_Buffer;
  82
  83         Float_Overlay = (int *) &x;
  84         Holding_Buffer = Float_Overlay [0];
  85
  86         Float_Overlay [0] = htonl (Holding_Buffer);
  87     } else {
  88         return;
  89     }
  90 }
  91
  92
  93 FGNativeFDM::FGNativeFDM() {
  94 }
  95
  96 FGNativeFDM::~FGNativeFDM() {
  97 }
  98
  99
 100 // open hailing frequencies
 101 bool FGNativeFDM::open() {
 102     if ( is_enabled() ) {
 103         SG_LOG( SG_IO, SG_ALERT, "This shouldn't happen, but the channel "
 104                 << "is already in use, ignoring" );
 105         return false;
 106     }
 107
 108     SGIOChannel *io = get_io_channel();
 109
 110     if ( ! io->open( get_direction() ) ) {
 111         SG_LOG( SG_IO, SG_ALERT, "Error opening channel communication layer." );
 112         return false;
 113     }
 114
 115     set_enabled( true );
 116
 117     // Is this really needed here ????
 118     cur_fdm_state->_set_Sea_level_radius( SG_EQUATORIAL_RADIUS_FT );
 119
 120     return true;
 121 }
 122
 123
 124 void FGProps2NetFDM( FGNetFDM *net, bool net_byte_order ) {
 125     unsigned int i;
 126
 127     // Version sanity checking
 128     net->version = FG_NET_FDM_VERSION;
 129
 130     // Aero parameters
 131     net->longitude = cur_fdm_state->get_Longitude();
 132     net->latitude = cur_fdm_state->get_Latitude();
 133     net->altitude = cur_fdm_state->get_Altitude() * SG_FEET_TO_METER;
 134     net->agl = cur_fdm_state->get_Altitude_AGL() * SG_FEET_TO_METER;
 135     net->phi = cur_fdm_state->get_Phi();
 136     net->theta = cur_fdm_state->get_Theta();
 137     net->psi = cur_fdm_state->get_Psi();
 138     net->alpha = cur_fdm_state->get_Alpha();
 139     net->beta = cur_fdm_state->get_Beta();
 140     net->phidot = cur_fdm_state->get_Phi_dot_degps() * SG_DEGREES_TO_RADIANS;
 141     net->thetadot = cur_fdm_state->get_Theta_dot_degps()
 142         * SG_DEGREES_TO_RADIANS;
 143     net->psidot = cur_fdm_state->get_Psi_dot_degps() * SG_DEGREES_TO_RADIANS;
 144
 145     net->vcas = cur_fdm_state->get_V_calibrated_kts();
 146     net->climb_rate = cur_fdm_state->get_Climb_Rate();
 147
 148     net->v_north = cur_fdm_state->get_V_north();
 149     net->v_east = cur_fdm_state->get_V_east();
 150     net->v_down = cur_fdm_state->get_V_down();
 151     net->v_wind_body_north = cur_fdm_state->get_uBody();
 152     net->v_wind_body_east = cur_fdm_state->get_vBody();
 153     net->v_wind_body_down = cur_fdm_state->get_wBody();
 154
 155     net->A_X_pilot = cur_fdm_state->get_A_X_pilot();
 156     net->A_Y_pilot = cur_fdm_state->get_A_Y_pilot();
 157     net->A_Z_pilot = cur_fdm_state->get_A_Z_pilot();
 158
 159     net->stall_warning = fgGetDouble("/sim/alarms/stall-warning", 0.0);
 160     net->slip_deg
 161       = fgGetDouble("/instrumentation/slip-skid-ball/indicated-slip-skid");
 162
 163     // Engine parameters
 164     net->num_engines = FGNetFDM::FG_MAX_ENGINES;
 165     for ( i = 0; i < net->num_engines; ++i ) {
 166         SGPropertyNode *node = fgGetNode("engines/engine", i, true);
 167         if ( node->getBoolValue( "running" ) ) {
 168             net->eng_state[i] = 2;
 169         } else if ( node->getBoolValue( "cranking" ) ) {
 170             net->eng_state[i] = 1;
 171         } else {
 172             net->eng_state[i] = 0;
 173         }
 174         net->rpm[i] = node->getDoubleValue( "rpm" );
 175         net->fuel_flow[i] = node->getDoubleValue( "fuel-flow-gph" );
 176         net->fuel_px[i] = node->getDoubleValue( "fuel-px-psi" );
 177         net->egt[i] = node->getDoubleValue( "egt-degf" );
 178         // cout << "egt = " << aero->EGT << endl;
 179         net->cht[i] = node->getDoubleValue( "cht-degf" );
 180         net->mp_osi[i] = node->getDoubleValue( "mp-osi" );
 181         net->tit[i] = node->getDoubleValue( "tit" );
 182         net->oil_temp[i] = node->getDoubleValue( "oil-temperature-degf" );
 183         net->oil_px[i] = node->getDoubleValue( "oil-pressure-psi" );
 184     }
 185
 186     // Consumables
 187     net->num_tanks = FGNetFDM::FG_MAX_TANKS;
 188     for ( i = 0; i < net->num_tanks; ++i ) {
 189         SGPropertyNode *node = fgGetNode("/consumables/fuel/tank", i, true);
 190         net->fuel_quantity[i] = node->getDoubleValue("level-gal_us");
 191     }
 192
 193     // Gear and flaps
 194     net->num_wheels = FGNetFDM::FG_MAX_WHEELS;
 195     for (i = 0; i < net->num_wheels; ++i ) {
 196         SGPropertyNode *node = fgGetNode("/gear/gear", i, true);
 197         net->wow[i] = node->getIntValue("wow");
 198         net->gear_pos[i] = node->getDoubleValue("position-norm");
 199         net->gear_steer[i] = node->getDoubleValue("steering-norm");
 200         net->gear_compression[i] = node->getDoubleValue("compression-norm");
 201     }
 202
 203     // the following really aren't used in this context
 204     net->cur_time = globals->get_time_params()->get_cur_time();
 205     net->warp = globals->get_warp();
 206     net->visibility = fgGetDouble("/environment/visibility-m");
 207
 208     // Control surface positions
 209     SGPropertyNode *node = fgGetNode("/surface-positions", true);
 210     net->elevator = node->getDoubleValue( "elevator-pos-norm" );
 211     net->elevator_trim_tab
 212         = node->getDoubleValue( "elevator-trim-tab-pos-norm" );
 213     // FIXME: CLO 10/28/04 - This really should be separated out into 2 values
 214     net->left_flap = node->getDoubleValue( "flap-pos-norm" );
 215     net->right_flap = node->getDoubleValue( "flap-pos-norm" );
 216     net->left_aileron = node->getDoubleValue( "left-aileron-pos-norm" );
 217     net->right_aileron = node->getDoubleValue( "right-aileron-pos-norm" );
 218     net->rudder = node->getDoubleValue( "rudder-pos-norm" );
 219     net->nose_wheel = node->getDoubleValue( "nose-wheel-pos-norm" );
 220     net->speedbrake = node->getDoubleValue( "speedbrake-pos-norm" );
 221     net->spoilers = node->getDoubleValue( "spoilers-pos-norm" );
 222
 223     if ( net_byte_order ) {
 224         // Convert the net buffer to network format
 225         net->version = htonl(net->version);
 226
 227         htond(net->longitude);
 228         htond(net->latitude);
 229         htond(net->altitude);
 230         htonf(net->agl);
 231         htonf(net->phi);
 232         htonf(net->theta);
 233         htonf(net->psi);
 234         htonf(net->alpha);
 235         htonf(net->beta);
 236
 237         htonf(net->phidot);
 238         htonf(net->thetadot);
 239         htonf(net->psidot);
 240         htonf(net->vcas);
 241         htonf(net->climb_rate);
 242         htonf(net->v_north);
 243         htonf(net->v_east);
 244         htonf(net->v_down);
 245         htonf(net->v_wind_body_north);
 246         htonf(net->v_wind_body_east);
 247         htonf(net->v_wind_body_down);
 248
 249         htonf(net->A_X_pilot);
 250         htonf(net->A_Y_pilot);
 251         htonf(net->A_Z_pilot);
 252
 253         htonf(net->stall_warning);
 254         htonf(net->slip_deg);
 255
 256         for ( i = 0; i < net->num_engines; ++i ) {
 257             net->eng_state[i] = htonl(net->eng_state[i]);
 258             htonf(net->rpm[i]);
 259             htonf(net->fuel_flow[i]);
 260             htonf(net->fuel_px[i]);
 261             htonf(net->egt[i]);
 262             htonf(net->cht[i]);
 263             htonf(net->mp_osi[i]);
 264             htonf(net->tit[i]);
 265             htonf(net->oil_temp[i]);
 266             htonf(net->oil_px[i]);
 267         }
 268         net->num_engines = htonl(net->num_engines);
 269
 270         for ( i = 0; i < net->num_tanks; ++i ) {
 271             htonf(net->fuel_quantity[i]);
 272         }
 273         net->num_tanks = htonl(net->num_tanks);
 274
 275         for ( i = 0; i < net->num_wheels; ++i ) {
 276             net->wow[i] = htonl(net->wow[i]);
 277             htonf(net->gear_pos[i]);
 278             htonf(net->gear_steer[i]);
 279             htonf(net->gear_compression[i]);
 280         }
 281         net->num_wheels = htonl(net->num_wheels);
 282
 283         net->cur_time = htonl( net->cur_time );
 284         net->warp = htonl( net->warp );
 285         htonf(net->visibility);
 286
 287         htonf(net->elevator);
 288         htonf(net->elevator_trim_tab);
 289         htonf(net->left_flap);
 290         htonf(net->right_flap);
 291         htonf(net->left_aileron);
 292         htonf(net->right_aileron);
 293         htonf(net->rudder);
 294         htonf(net->nose_wheel);
 295         htonf(net->speedbrake);
 296         htonf(net->spoilers);
 297     }
 298 }
 299
 300
 301 void FGNetFDM2Props( FGNetFDM *net, bool net_byte_order ) {
 302     unsigned int i;
 303
 304     if ( net_byte_order ) {
 305         // Convert to the net buffer from network format
 306         net->version = ntohl(net->version);
 307
 308         htond(net->longitude);
 309         htond(net->latitude);
 310         htond(net->altitude);
 311         htonf(net->agl);
 312         htonf(net->phi);
 313         htonf(net->theta);
 314         htonf(net->psi);
 315         htonf(net->alpha);
 316         htonf(net->beta);
 317
 318         htonf(net->phidot);
 319         htonf(net->thetadot);
 320         htonf(net->psidot);
 321         htonf(net->vcas);
 322         htonf(net->climb_rate);
 323         htonf(net->v_north);
 324         htonf(net->v_east);
 325         htonf(net->v_down);
 326         htonf(net->v_wind_body_north);
 327         htonf(net->v_wind_body_east);
 328         htonf(net->v_wind_body_down);
 329
 330         htonf(net->A_X_pilot);
 331         htonf(net->A_Y_pilot);
 332         htonf(net->A_Z_pilot);
 333
 334         htonf(net->stall_warning);
 335         htonf(net->slip_deg);
 336
 337         net->num_engines = htonl(net->num_engines);
 338         for ( i = 0; i < net->num_engines; ++i ) {
 339             net->eng_state[i] = htonl(net->eng_state[i]);
 340             htonf(net->rpm[i]);
 341             htonf(net->fuel_flow[i]);
 342             htonf(net->fuel_px[i]);
 343             htonf(net->egt[i]);
 344             htonf(net->cht[i]);
 345             htonf(net->mp_osi[i]);
 346             htonf(net->tit[i]);
 347             htonf(net->oil_temp[i]);
 348             htonf(net->oil_px[i]);
 349         }
 350
 351         net->num_tanks = htonl(net->num_tanks);
 352         for ( i = 0; i < net->num_tanks; ++i ) {
 353             htonf(net->fuel_quantity[i]);
 354         }
 355
 356         net->num_wheels = htonl(net->num_wheels);
 357         for ( i = 0; i < net->num_wheels; ++i ) {
 358             net->wow[i] = htonl(net->wow[i]);
 359             htonf(net->gear_pos[i]);
 360             htonf(net->gear_steer[i]);
 361             htonf(net->gear_compression[i]);
 362         }
 363
 364         net->cur_time = htonl(net->cur_time);
 365         net->warp = ntohl(net->warp);
 366         htonf(net->visibility);
 367
 368         htonf(net->elevator);
 369         htonf(net->elevator_trim_tab);
 370         htonf(net->left_flap);
 371         htonf(net->right_flap);
 372         htonf(net->left_aileron);
 373         htonf(net->right_aileron);
 374         htonf(net->rudder);
 375         htonf(net->nose_wheel);
 376         htonf(net->speedbrake);
 377         htonf(net->spoilers);
 378     }
 379
 380     if ( net->version == FG_NET_FDM_VERSION ) {
 381         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 382         // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
 383         //      << endl;
 384         cur_fdm_state->_updateGeodeticPosition( net->latitude,
 385                                                 net->longitude,
 386                                                 net->altitude
 387                                                   * SG_METER_TO_FEET );
 388         if ( net->agl > -9000 ) {
 389             cur_fdm_state->_set_Altitude_AGL( net->agl * SG_METER_TO_FEET );
 390         } else {
 391             double agl_m = net->altitude
 392               - cur_fdm_state->get_Runway_altitude_m();
 393             cur_fdm_state->_set_Altitude_AGL( agl_m * SG_METER_TO_FEET );
 394         }
 395         cur_fdm_state->_set_Euler_Angles( net->phi,
 396                                           net->theta,
 397                                           net->psi );
 398         cur_fdm_state->_set_Alpha( net->alpha );
 399         cur_fdm_state->_set_Beta( net->beta );
 400         cur_fdm_state->_set_Euler_Rates( net->phidot,
 401                                          net->thetadot,
 402                                          net->psidot );
 403         cur_fdm_state->_set_V_calibrated_kts( net->vcas );
 404         cur_fdm_state->_set_Climb_Rate( net->climb_rate );
 405         cur_fdm_state->_set_Velocities_Local( net->v_north,
 406                                               net->v_east,
 407                                               net->v_down );
 408         cur_fdm_state->_set_Velocities_Wind_Body( net->v_wind_body_north,
 409                                                   net->v_wind_body_east,
 410                                                   net->v_wind_body_down );
 411
 412         cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
 413                                                net->A_Y_pilot,
 414                                                net->A_Z_pilot );
 415
 416         fgSetDouble( "/sim/alarms/stall-warning", net->stall_warning );
 417         fgSetDouble( "/instrumentation/slip-skid-ball/indicated-slip-skid",
 418                      net->slip_deg );
 419         fgSetBool( "/instrumentation/slip-skid-ball/override", true );
 420
 421         for ( i = 0; i < net->num_engines; ++i ) {
 422             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 423
 424             // node->setBoolValue("running", t->isRunning());
 425             // node->setBoolValue("cranking", t->isCranking());
 426
 427             // cout << net->eng_state[i] << endl;
 428             if ( net->eng_state[i] == 0 ) {
 429                 node->setBoolValue( "cranking", false );
 430                 node->setBoolValue( "running", false );
 431             } else if ( net->eng_state[i] == 1 ) {
 432                 node->setBoolValue( "cranking", true );
 433                 node->setBoolValue( "running", false );
 434             } else if ( net->eng_state[i] == 2 ) {
 435                 node->setBoolValue( "cranking", false );
 436                 node->setBoolValue( "running", true );
 437             }
 438
 439             node->setDoubleValue( "rpm", net->rpm[i] );
 440             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 441             node->setDoubleValue( "fuel-px-psi", net->fuel_px[i] );
 442             node->setDoubleValue( "egt-degf", net->egt[i] );
 443             node->setDoubleValue( "cht-degf", net->cht[i] );
 444             node->setDoubleValue( "mp-osi", net->mp_osi[i] );
 445             node->setDoubleValue( "tit", net->tit[i] );
 446             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 447             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 448         }
 449
 450         for (i = 0; i < net->num_tanks; ++i ) {
 451             SGPropertyNode * node
 452                 = fgGetNode("/consumables/fuel/tank", i, true);
 453             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 454         }
 455
 456         for (i = 0; i < net->num_wheels; ++i ) {
 457             SGPropertyNode * node = fgGetNode("/gear/gear", i, true);
 458             node->setDoubleValue("wow", net->wow[i] );
 459             node->setDoubleValue("position-norm", net->gear_pos[i] );
 460             node->setDoubleValue("steering-norm", net->gear_steer[i] );
 461             node->setDoubleValue("compression-norm", net->gear_compression[i] );
 462         }
 463
 464         /* these are ignored for now  ... */
 465         /*
 466         if ( net->cur_time ) {
 467             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 468         }
 469
 470         globals->set_warp( net->warp );
 471         last_warp = net->warp;
 472         */
 473
 474         SGPropertyNode *node = fgGetNode("/surface-positions", true);
 475         node->setDoubleValue("elevator-pos-norm", net->elevator);
 476         node->setDoubleValue("elevator-trim-tab-pos-norm",
 477                              net->elevator_trim_tab);
 478         // FIXME: CLO 10/28/04 - This really should be separated out
 479         // into 2 values
 480         node->setDoubleValue("flap-pos-norm", net->left_flap);
 481         node->setDoubleValue("flap-pos-norm", net->right_flap);
 482         node->setDoubleValue("left-aileron-pos-norm", net->left_aileron);
 483         node->setDoubleValue("right-aileron-pos-norm", net->right_aileron);
 484         node->setDoubleValue("rudder-pos-norm", net->rudder);
 485         node->setDoubleValue("nose-wheel-pos-norm", net->nose_wheel);
 486         node->setDoubleValue("speedbrake-pos-norm", net->speedbrake);
 487         node->setDoubleValue("spoilers-pos-norm", net->spoilers);
 488     } else {
 489         SG_LOG( SG_IO, SG_ALERT,
 490                 "Error: version mismatch in FGNetFDM2Props()" );
 491         SG_LOG( SG_IO, SG_ALERT,
 492                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 493         SG_LOG( SG_IO, SG_ALERT,
 494                 "\tNeeds to upgrade net_fdm.hxx and recompile." );
 495     }
 496 }
 497
 498
 499 // process work for this port
 500 bool FGNativeFDM::process() {
 501     SGIOChannel *io = get_io_channel();
 502     int length = sizeof(buf);
 503
 504     if ( get_direction() == SG_IO_OUT ) {
 505         // cout << "size of cur_fdm_state = " << length << endl;
 506         FGProps2NetFDM( &buf );
 507         if ( ! io->write( (char *)(& buf), length ) ) {
 508             SG_LOG( SG_IO, SG_ALERT, "Error writing data." );
 509             return false;
 510         }
 511     } else if ( get_direction() == SG_IO_IN ) {
 512         if ( io->get_type() == sgFileType ) {
 513             if ( io->read( (char *)(& buf), length ) == length ) {
 514                 SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 515                 FGNetFDM2Props( &buf );
 516             }
 517         } else {
 518             int result;
 519             result = io->read( (char *)(& buf), length );
 520             while ( result == length ) {
 521                 if ( result == length ) {
 522                     SG_LOG( SG_IO, SG_DEBUG, "  Success reading data." );
 523                     FGNetFDM2Props( &buf );
 524                 }
 525                 result = io->read( (char *)(& buf), length );
 526             }
 527         }
 528     }
 529
 530     return true;
 531 }
 532
 533
 534 // close the channel
 535 bool FGNativeFDM::close() {
 536     SGIOChannel *io = get_io_channel();
 537
 538     set_enabled( false );
 539
 540     if ( ! io->close() ) {
 541         return false;
 542     }
 543
 544     return true;
 545 }