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/flightProperties.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     fgSetDouble("/position/sea-level-radius-ft", SG_EQUATORIAL_RADIUS_FT);
 119
 120
 121
 122     return true;
 123 }
 124
 125
 126 void FGProps2NetFDM( FGNetFDM *net, bool net_byte_order ) {
 127     unsigned int i;
 128
 129     FlightProperties fdm_state;
 130
 131     // Version sanity checking
 132     net->version = FG_NET_FDM_VERSION;
 133
 134     // Aero parameters
 135     net->longitude = fdm_state.get_Longitude();
 136     net->latitude = fdm_state.get_Latitude();
 137     net->altitude = fdm_state.get_Altitude() * SG_FEET_TO_METER;
 138     net->agl = fdm_state.get_Altitude_AGL() * SG_FEET_TO_METER;
 139     net->phi = fdm_state.get_Phi();
 140     net->theta = fdm_state.get_Theta();
 141     net->psi = fdm_state.get_Psi();
 142     net->alpha = fdm_state.get_Alpha();
 143     net->beta = fdm_state.get_Beta();
 144     net->phidot = fdm_state.get_Phi_dot_degps() * SG_DEGREES_TO_RADIANS;
 145     net->thetadot = fdm_state.get_Theta_dot_degps()
 146         * SG_DEGREES_TO_RADIANS;
 147     net->psidot = fdm_state.get_Psi_dot_degps() * SG_DEGREES_TO_RADIANS;
 148
 149     net->vcas = fdm_state.get_V_calibrated_kts();
 150     net->climb_rate = fdm_state.get_Climb_Rate();
 151
 152     net->v_north = fdm_state.get_V_north();
 153     net->v_east = fdm_state.get_V_east();
 154     net->v_down = fdm_state.get_V_down();
 155     net->v_wind_body_north = fdm_state.get_uBody();
 156     net->v_wind_body_east = fdm_state.get_vBody();
 157     net->v_wind_body_down = fdm_state.get_wBody();
 158
 159     net->A_X_pilot = fdm_state.get_A_X_pilot();
 160     net->A_Y_pilot = fdm_state.get_A_Y_pilot();
 161     net->A_Z_pilot = fdm_state.get_A_Z_pilot();
 162
 163     net->stall_warning = fgGetDouble("/sim/alarms/stall-warning", 0.0);
 164     net->slip_deg
 165       = fgGetDouble("/instrumentation/slip-skid-ball/indicated-slip-skid");
 166
 167     // Engine parameters
 168     net->num_engines = FGNetFDM::FG_MAX_ENGINES;
 169     for ( i = 0; i < net->num_engines; ++i ) {
 170         SGPropertyNode *node = fgGetNode("engines/engine", i, true);
 171         if ( node->getBoolValue( "running" ) ) {
 172             net->eng_state[i] = 2;
 173         } else if ( node->getBoolValue( "cranking" ) ) {
 174             net->eng_state[i] = 1;
 175         } else {
 176             net->eng_state[i] = 0;
 177         }
 178         net->rpm[i] = node->getDoubleValue( "rpm" );
 179         net->fuel_flow[i] = node->getDoubleValue( "fuel-flow-gph" );
 180         net->fuel_px[i] = node->getDoubleValue( "fuel-px-psi" );
 181         net->egt[i] = node->getDoubleValue( "egt-degf" );
 182         // cout << "egt = " << aero->EGT << endl;
 183         net->cht[i] = node->getDoubleValue( "cht-degf" );
 184         net->mp_osi[i] = node->getDoubleValue( "mp-osi" );
 185         net->tit[i] = node->getDoubleValue( "tit" );
 186         net->oil_temp[i] = node->getDoubleValue( "oil-temperature-degf" );
 187         net->oil_px[i] = node->getDoubleValue( "oil-pressure-psi" );
 188     }
 189
 190     // Consumables
 191     net->num_tanks = FGNetFDM::FG_MAX_TANKS;
 192     for ( i = 0; i < net->num_tanks; ++i ) {
 193         SGPropertyNode *node = fgGetNode("/consumables/fuel/tank", i, true);
 194         net->fuel_quantity[i] = node->getDoubleValue("level-gal_us");
 195     }
 196
 197     // Gear and flaps
 198     net->num_wheels = FGNetFDM::FG_MAX_WHEELS;
 199     for (i = 0; i < net->num_wheels; ++i ) {
 200         SGPropertyNode *node = fgGetNode("/gear/gear", i, true);
 201         net->wow[i] = node->getIntValue("wow");
 202         net->gear_pos[i] = node->getDoubleValue("position-norm");
 203         net->gear_steer[i] = node->getDoubleValue("steering-norm");
 204         net->gear_compression[i] = node->getDoubleValue("compression-norm");
 205     }
 206
 207     // the following really aren't used in this context
 208     net->cur_time = globals->get_time_params()->get_cur_time();
 209     net->warp = globals->get_warp();
 210     net->visibility = fgGetDouble("/environment/visibility-m");
 211
 212     // Control surface positions
 213     SGPropertyNode *node = fgGetNode("/surface-positions", true);
 214     net->elevator = node->getDoubleValue( "elevator-pos-norm" );
 215     net->elevator_trim_tab
 216         = node->getDoubleValue( "elevator-trim-tab-pos-norm" );
 217     // FIXME: CLO 10/28/04 - This really should be separated out into 2 values
 218     net->left_flap = node->getDoubleValue( "flap-pos-norm" );
 219     net->right_flap = node->getDoubleValue( "flap-pos-norm" );
 220     net->left_aileron = node->getDoubleValue( "left-aileron-pos-norm" );
 221     net->right_aileron = node->getDoubleValue( "right-aileron-pos-norm" );
 222     net->rudder = node->getDoubleValue( "rudder-pos-norm" );
 223     net->nose_wheel = node->getDoubleValue( "nose-wheel-pos-norm" );
 224     net->speedbrake = node->getDoubleValue( "speedbrake-pos-norm" );
 225     net->spoilers = node->getDoubleValue( "spoilers-pos-norm" );
 226
 227     if ( net_byte_order ) {
 228         // Convert the net buffer to network format
 229         net->version = htonl(net->version);
 230
 231         htond(net->longitude);
 232         htond(net->latitude);
 233         htond(net->altitude);
 234         htonf(net->agl);
 235         htonf(net->phi);
 236         htonf(net->theta);
 237         htonf(net->psi);
 238         htonf(net->alpha);
 239         htonf(net->beta);
 240
 241         htonf(net->phidot);
 242         htonf(net->thetadot);
 243         htonf(net->psidot);
 244         htonf(net->vcas);
 245         htonf(net->climb_rate);
 246         htonf(net->v_north);
 247         htonf(net->v_east);
 248         htonf(net->v_down);
 249         htonf(net->v_wind_body_north);
 250         htonf(net->v_wind_body_east);
 251         htonf(net->v_wind_body_down);
 252
 253         htonf(net->A_X_pilot);
 254         htonf(net->A_Y_pilot);
 255         htonf(net->A_Z_pilot);
 256
 257         htonf(net->stall_warning);
 258         htonf(net->slip_deg);
 259
 260         for ( i = 0; i < net->num_engines; ++i ) {
 261             net->eng_state[i] = htonl(net->eng_state[i]);
 262             htonf(net->rpm[i]);
 263             htonf(net->fuel_flow[i]);
 264             htonf(net->fuel_px[i]);
 265             htonf(net->egt[i]);
 266             htonf(net->cht[i]);
 267             htonf(net->mp_osi[i]);
 268             htonf(net->tit[i]);
 269             htonf(net->oil_temp[i]);
 270             htonf(net->oil_px[i]);
 271         }
 272         net->num_engines = htonl(net->num_engines);
 273
 274         for ( i = 0; i < net->num_tanks; ++i ) {
 275             htonf(net->fuel_quantity[i]);
 276         }
 277         net->num_tanks = htonl(net->num_tanks);
 278
 279         for ( i = 0; i < net->num_wheels; ++i ) {
 280             net->wow[i] = htonl(net->wow[i]);
 281             htonf(net->gear_pos[i]);
 282             htonf(net->gear_steer[i]);
 283             htonf(net->gear_compression[i]);
 284         }
 285         net->num_wheels = htonl(net->num_wheels);
 286
 287         net->cur_time = htonl( net->cur_time );
 288         net->warp = htonl( net->warp );
 289         htonf(net->visibility);
 290
 291         htonf(net->elevator);
 292         htonf(net->elevator_trim_tab);
 293         htonf(net->left_flap);
 294         htonf(net->right_flap);
 295         htonf(net->left_aileron);
 296         htonf(net->right_aileron);
 297         htonf(net->rudder);
 298         htonf(net->nose_wheel);
 299         htonf(net->speedbrake);
 300         htonf(net->spoilers);
 301     }
 302 }
 303
 304
 305 void FGNetFDM2Props( FGNetFDM *net, bool net_byte_order ) {
 306     unsigned int i;
 307     FlightProperties fdm_state;
 308
 309     if ( net_byte_order ) {
 310         // Convert to the net buffer from network format
 311         net->version = ntohl(net->version);
 312
 313         htond(net->longitude);
 314         htond(net->latitude);
 315         htond(net->altitude);
 316         htonf(net->agl);
 317         htonf(net->phi);
 318         htonf(net->theta);
 319         htonf(net->psi);
 320         htonf(net->alpha);
 321         htonf(net->beta);
 322
 323         htonf(net->phidot);
 324         htonf(net->thetadot);
 325         htonf(net->psidot);
 326         htonf(net->vcas);
 327         htonf(net->climb_rate);
 328         htonf(net->v_north);
 329         htonf(net->v_east);
 330         htonf(net->v_down);
 331         htonf(net->v_wind_body_north);
 332         htonf(net->v_wind_body_east);
 333         htonf(net->v_wind_body_down);
 334
 335         htonf(net->A_X_pilot);
 336         htonf(net->A_Y_pilot);
 337         htonf(net->A_Z_pilot);
 338
 339         htonf(net->stall_warning);
 340         htonf(net->slip_deg);
 341
 342         net->num_engines = htonl(net->num_engines);
 343         for ( i = 0; i < net->num_engines; ++i ) {
 344             net->eng_state[i] = htonl(net->eng_state[i]);
 345             htonf(net->rpm[i]);
 346             htonf(net->fuel_flow[i]);
 347             htonf(net->fuel_px[i]);
 348             htonf(net->egt[i]);
 349             htonf(net->cht[i]);
 350             htonf(net->mp_osi[i]);
 351             htonf(net->tit[i]);
 352             htonf(net->oil_temp[i]);
 353             htonf(net->oil_px[i]);
 354         }
 355
 356         net->num_tanks = htonl(net->num_tanks);
 357         for ( i = 0; i < net->num_tanks; ++i ) {
 358             htonf(net->fuel_quantity[i]);
 359         }
 360
 361         net->num_wheels = htonl(net->num_wheels);
 362         for ( i = 0; i < net->num_wheels; ++i ) {
 363             net->wow[i] = htonl(net->wow[i]);
 364             htonf(net->gear_pos[i]);
 365             htonf(net->gear_steer[i]);
 366             htonf(net->gear_compression[i]);
 367         }
 368
 369         net->cur_time = htonl(net->cur_time);
 370         net->warp = ntohl(net->warp);
 371         htonf(net->visibility);
 372
 373         htonf(net->elevator);
 374         htonf(net->elevator_trim_tab);
 375         htonf(net->left_flap);
 376         htonf(net->right_flap);
 377         htonf(net->left_aileron);
 378         htonf(net->right_aileron);
 379         htonf(net->rudder);
 380         htonf(net->nose_wheel);
 381         htonf(net->speedbrake);
 382         htonf(net->spoilers);
 383     }
 384
 385     if ( net->version == FG_NET_FDM_VERSION ) {
 386         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 387         // cout << "sea level rad = " << fdm_state.get_Sea_level_radius()
 388         //      << endl;
 389
 390       fdm_state.set_Latitude(net->latitude);
 391         fdm_state.set_Longitude(net->longitude);
 392         fdm_state.set_Altitude(net->altitude * SG_METER_TO_FEET);
 393
 394         if ( net->agl > -9000 ) {
 395             fdm_state.set_Altitude_AGL( net->agl * SG_METER_TO_FEET );
 396         } else {
 397             double agl_m = net->altitude
 398               - fdm_state.get_Runway_altitude_m();
 399             fdm_state.set_Altitude_AGL( agl_m * SG_METER_TO_FEET );
 400         }
 401         fdm_state.set_Euler_Angles( net->phi,
 402                                           net->theta,
 403                                           net->psi );
 404         fdm_state.set_Alpha( net->alpha );
 405         fdm_state.set_Beta( net->beta );
 406         fdm_state.set_Euler_Rates( net->phidot,
 407                                          net->thetadot,
 408                                          net->psidot );
 409         fdm_state.set_V_calibrated_kts( net->vcas );
 410         fdm_state.set_Climb_Rate( net->climb_rate );
 411         fdm_state.set_Velocities_Local( net->v_north,
 412                                               net->v_east,
 413                                               net->v_down );
 414         fdm_state.set_Velocities_Wind_Body( net->v_wind_body_north,
 415                                                   net->v_wind_body_east,
 416                                                   net->v_wind_body_down );
 417
 418         fdm_state.set_Accels_Pilot_Body( net->A_X_pilot,
 419                                                net->A_Y_pilot,
 420                                                net->A_Z_pilot );
 421
 422         fgSetDouble( "/sim/alarms/stall-warning", net->stall_warning );
 423         fgSetDouble( "/instrumentation/slip-skid-ball/indicated-slip-skid",
 424                      net->slip_deg );
 425         fgSetBool( "/instrumentation/slip-skid-ball/override", true );
 426
 427         for ( i = 0; i < net->num_engines; ++i ) {
 428             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 429
 430             // node->setBoolValue("running", t->isRunning());
 431             // node->setBoolValue("cranking", t->isCranking());
 432
 433             // cout << net->eng_state[i] << endl;
 434             if ( net->eng_state[i] == 0 ) {
 435                 node->setBoolValue( "cranking", false );
 436                 node->setBoolValue( "running", false );
 437             } else if ( net->eng_state[i] == 1 ) {
 438                 node->setBoolValue( "cranking", true );
 439                 node->setBoolValue( "running", false );
 440             } else if ( net->eng_state[i] == 2 ) {
 441                 node->setBoolValue( "cranking", false );
 442                 node->setBoolValue( "running", true );
 443             }
 444
 445             node->setDoubleValue( "rpm", net->rpm[i] );
 446             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 447             node->setDoubleValue( "fuel-px-psi", net->fuel_px[i] );
 448             node->setDoubleValue( "egt-degf", net->egt[i] );
 449             node->setDoubleValue( "cht-degf", net->cht[i] );
 450             node->setDoubleValue( "mp-osi", net->mp_osi[i] );
 451             node->setDoubleValue( "tit", net->tit[i] );
 452             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 453             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 454         }
 455
 456         for (i = 0; i < net->num_tanks; ++i ) {
 457             SGPropertyNode * node
 458                 = fgGetNode("/consumables/fuel/tank", i, true);
 459             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 460         }
 461
 462         for (i = 0; i < net->num_wheels; ++i ) {
 463             SGPropertyNode * node = fgGetNode("/gear/gear", i, true);
 464             node->setDoubleValue("wow", net->wow[i] );
 465             node->setDoubleValue("position-norm", net->gear_pos[i] );
 466             node->setDoubleValue("steering-norm", net->gear_steer[i] );
 467             node->setDoubleValue("compression-norm", net->gear_compression[i] );
 468         }
 469
 470         /* these are ignored for now  ... */
 471         /*
 472         if ( net->cur_time ) {
 473             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 474         }
 475
 476         globals->set_warp( net->warp );
 477         last_warp = net->warp;
 478         */
 479
 480         SGPropertyNode *node = fgGetNode("/surface-positions", true);
 481         node->setDoubleValue("elevator-pos-norm", net->elevator);
 482         node->setDoubleValue("elevator-trim-tab-pos-norm",
 483                              net->elevator_trim_tab);
 484         // FIXME: CLO 10/28/04 - This really should be separated out
 485         // into 2 values
 486         node->setDoubleValue("flap-pos-norm", net->left_flap);
 487         node->setDoubleValue("flap-pos-norm", net->right_flap);
 488         node->setDoubleValue("left-aileron-pos-norm", net->left_aileron);
 489         node->setDoubleValue("right-aileron-pos-norm", net->right_aileron);
 490         node->setDoubleValue("rudder-pos-norm", net->rudder);
 491         node->setDoubleValue("nose-wheel-pos-norm", net->nose_wheel);
 492         node->setDoubleValue("speedbrake-pos-norm", net->speedbrake);
 493         node->setDoubleValue("spoilers-pos-norm", net->spoilers);
 494     } else {
 495         SG_LOG( SG_IO, SG_ALERT,
 496                 "Error: version mismatch in FGNetFDM2Props()" );
 497         SG_LOG( SG_IO, SG_ALERT,
 498                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 499         SG_LOG( SG_IO, SG_ALERT,
 500                 "\tNeeds to upgrade net_fdm.hxx and recompile." );
 501     }
 502 }
 503
 504
 505 // process work for this port
 506 bool FGNativeFDM::process() {
 507     SGIOChannel *io = get_io_channel();
 508     int length = sizeof(buf);
 509
 510     if ( get_direction() == SG_IO_OUT ) {
 511
 512         FGProps2NetFDM( &buf );
 513         if ( ! io->write( (char *)(& buf), length ) ) {
 514             SG_LOG( SG_IO, SG_ALERT, "Error writing data." );
 515             return false;
 516         }
 517     } else if ( get_direction() == SG_IO_IN ) {
 518         if ( io->get_type() == sgFileType ) {
 519             if ( io->read( (char *)(& buf), length ) == length ) {
 520                 SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 521                 FGNetFDM2Props( &buf );
 522             }
 523         } else {
 524             int result;
 525             result = io->read( (char *)(& buf), length );
 526             while ( result == length ) {
 527                 if ( result == length ) {
 528                     SG_LOG( SG_IO, SG_DEBUG, "  Success reading data." );
 529                     FGNetFDM2Props( &buf );
 530                 }
 531                 result = io->read( (char *)(& buf), length );
 532             }
 533         }
 534     }
 535
 536     return true;
 537 }
 538
 539
 540 // close the channel
 541 bool FGNativeFDM::close() {
 542     SGIOChannel *io = get_io_channel();
 543
 544     set_enabled( false );
 545
 546     if ( ! io->close() ) {
 547         return false;
 548     }
 549
 550     return true;
 551 }