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 - curt@flightgear.org
   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 #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
  38 #include "native_fdm.hxx"
  39
  40 // FreeBSD works better with this included last ... (?)
  41 #if defined(WIN32) && !defined(__CYGWIN__)
  42 #  include <windows.h>
  43 #else
  44 #  include <netinet/in.h>       // htonl() ntohl()
  45 #endif
  46
  47
  48 // The function htond is defined this way due to the way some
  49 // processors and OSes treat floating point values.  Some will raise
  50 // an exception whenever a "bad" floating point value is loaded into a
  51 // floating point register.  Solaris is notorious for this, but then
  52 // so is LynxOS on the PowerPC.  By translating the data in place,
  53 // there is no need to load a FP register with the "corruped" floating
  54 // point value.  By doing the BIG_ENDIAN test, I can optimize the
  55 // routine for big-endian processors so it can be as efficient as
  56 // possible
  57 static void htond (double &x)
  58 {
  59     if ( sgIsLittleEndian() ) {
  60         int    *Double_Overlay;
  61         int     Holding_Buffer;
  62
  63         Double_Overlay = (int *) &x;
  64         Holding_Buffer = Double_Overlay [0];
  65
  66         Double_Overlay [0] = htonl (Double_Overlay [1]);
  67         Double_Overlay [1] = htonl (Holding_Buffer);
  68     } else {
  69         return;
  70     }
  71 }
  72
  73
  74 FGNativeFDM::FGNativeFDM() {
  75 }
  76
  77 FGNativeFDM::~FGNativeFDM() {
  78 }
  79
  80
  81 // open hailing frequencies
  82 bool FGNativeFDM::open() {
  83     if ( is_enabled() ) {
  84         SG_LOG( SG_IO, SG_ALERT, "This shouldn't happen, but the channel "
  85                 << "is already in use, ignoring" );
  86         return false;
  87     }
  88
  89     SGIOChannel *io = get_io_channel();
  90
  91     if ( ! io->open( get_direction() ) ) {
  92         SG_LOG( SG_IO, SG_ALERT, "Error opening channel communication layer." );
  93         return false;
  94     }
  95
  96     set_enabled( true );
  97
  98     cur_fdm_state->_set_Sea_level_radius( SG_EQUATORIAL_RADIUS_FT );
  99     return true;
 100 }
 101
 102
 103 void FGProps2NetFDM( FGNetFDM *net ) {
 104     int i;
 105
 106     // Version sanity checking
 107     net->version = FG_NET_FDM_VERSION;
 108
 109     // Aero parameters
 110     net->longitude = cur_fdm_state->get_Longitude();
 111     net->latitude = cur_fdm_state->get_Latitude();
 112     net->altitude = cur_fdm_state->get_Altitude() * SG_FEET_TO_METER;
 113     net->phi = cur_fdm_state->get_Phi();
 114     net->theta = cur_fdm_state->get_Theta();
 115     net->psi = cur_fdm_state->get_Psi();
 116     net->phidot = cur_fdm_state->get_Phi_dot_degps() * SG_DEGREES_TO_RADIANS;
 117     net->thetadot = cur_fdm_state->get_Theta_dot_degps()
 118         * SG_DEGREES_TO_RADIANS;
 119     net->psidot = cur_fdm_state->get_Psi_dot_degps() * SG_DEGREES_TO_RADIANS;
 120
 121     net->vcas = cur_fdm_state->get_V_calibrated_kts();
 122     net->climb_rate = cur_fdm_state->get_Climb_Rate();
 123
 124     net->v_north = cur_fdm_state->get_V_north();
 125     net->v_east = cur_fdm_state->get_V_east();
 126     net->v_down = cur_fdm_state->get_V_down();
 127     net->v_wind_body_north = cur_fdm_state->get_uBody();
 128     net->v_wind_body_east = cur_fdm_state->get_vBody();
 129     net->v_wind_body_down = cur_fdm_state->get_wBody();
 130     net->stall_warning = fgGetDouble("/sim/alarms/stall-warning", 0.0);
 131
 132     net->A_X_pilot = cur_fdm_state->get_A_X_pilot();
 133     net->A_Y_pilot = cur_fdm_state->get_A_Y_pilot();
 134     net->A_Z_pilot = cur_fdm_state->get_A_Z_pilot();
 135
 136     // Engine parameters
 137     net->num_engines = FGNetFDM::FG_MAX_ENGINES;
 138     for ( i = 0; i < net->num_engines; ++i ) {
 139         SGPropertyNode *node = fgGetNode("engines/engine", i, true);
 140         if ( node->getBoolValue( "running" ) ) {
 141             net->eng_state[0] = 2;
 142         } else if ( node->getBoolValue( "cranking" ) ) {
 143             net->eng_state[0] = 1;
 144         } else {
 145             net->eng_state[0] = 0;
 146         }
 147         net->rpm[i] = node->getDoubleValue( "rpm" );
 148         net->fuel_flow[i] = node->getDoubleValue( "fuel-flow-gph" );
 149         net->EGT[i] = node->getDoubleValue( "egt-degf" );
 150         // cout << "egt = " << aero->EGT << endl;
 151         net->oil_temp[i] = node->getDoubleValue( "oil-temperature-degf" );
 152         net->oil_px[i] = node->getDoubleValue( "oil-pressure-psi" );
 153     }
 154
 155     // Consumables
 156     net->num_tanks = FGNetFDM::FG_MAX_TANKS;
 157     for ( i = 0; i < net->num_tanks; ++i ) {
 158         SGPropertyNode *node = fgGetNode("/consumables/fuel/tank", i, true);
 159         net->fuel_quantity[i] = node->getDoubleValue("level-gal_us");
 160     }
 161
 162     // Gear and flaps
 163     net->num_wheels = FGNetFDM::FG_MAX_WHEELS;
 164     for (i = 0; i < net->num_wheels; ++i ) {
 165         SGPropertyNode *node = fgGetNode("/gear/gear", i, true);
 166         net->wow[i] = node->getDoubleValue("wow");
 167     }
 168
 169     // cout << "Flap deflection = " << aero->dflap << endl;
 170     net->flap_deflection = fgGetDouble("/surface-positions/flap-pos-norm" );
 171
 172     // the following really aren't used in this context
 173     net->cur_time = globals->get_time_params()->get_cur_time();
 174     net->warp = globals->get_warp();
 175     net->visibility = fgGetDouble("/environment/visibility-m");
 176
 177     // Convert the net buffer to network format
 178     net->version = htonl(net->version);
 179
 180     htond(net->longitude);
 181     htond(net->latitude);
 182     htond(net->altitude);
 183     htond(net->phi);
 184     htond(net->theta);
 185     htond(net->psi);
 186
 187     htond(net->phidot);
 188     htond(net->thetadot);
 189     htond(net->psidot);
 190     htond(net->vcas);
 191     htond(net->climb_rate);
 192     htond(net->v_north);
 193     htond(net->v_east);
 194     htond(net->v_down);
 195     htond(net->v_wind_body_north);
 196     htond(net->v_wind_body_east);
 197     htond(net->v_wind_body_down);
 198     htond(net->stall_warning);
 199
 200     htond(net->A_X_pilot);
 201     htond(net->A_Y_pilot);
 202     htond(net->A_Z_pilot);
 203
 204     for ( i = 0; i < net->num_engines; ++i ) {
 205         htonl(net->eng_state[i]);
 206         htond(net->rpm[i]);
 207         htond(net->fuel_flow[i]);
 208         htond(net->EGT[i]);
 209         htond(net->oil_temp[i]);
 210         htond(net->oil_px[i]);
 211     }
 212     net->num_engines = htonl(net->num_engines);
 213
 214     for ( i = 0; i < net->num_tanks; ++i ) {
 215         htond(net->fuel_quantity[i]);
 216     }
 217     net->num_tanks = htonl(net->num_tanks);
 218
 219     for ( i = 0; i < net->num_wheels; ++i ) {
 220         net->wow[i] = htonl(net->wow[i]);
 221     }
 222     net->num_wheels = htonl(net->num_wheels);
 223     htond(net->flap_deflection);
 224
 225     net->cur_time = htonl( net->cur_time );
 226     net->warp = htonl( net->warp );
 227     htond(net->visibility);
 228 }
 229
 230
 231 void FGNetFDM2Props( FGNetFDM *net ) {
 232     int i;
 233
 234     // Convert to the net buffer from network format
 235     net->version = ntohl(net->version);
 236
 237     htond(net->longitude);
 238     htond(net->latitude);
 239     htond(net->altitude);
 240     htond(net->phi);
 241     htond(net->theta);
 242     htond(net->psi);
 243
 244     htond(net->phidot);
 245     htond(net->thetadot);
 246     htond(net->psidot);
 247     htond(net->vcas);
 248     htond(net->climb_rate);
 249     htond(net->v_north);
 250     htond(net->v_east);
 251     htond(net->v_down);
 252     htond(net->v_wind_body_north);
 253     htond(net->v_wind_body_east);
 254     htond(net->v_wind_body_down);
 255     htond(net->stall_warning);
 256
 257     htond(net->A_X_pilot);
 258     htond(net->A_Y_pilot);
 259     htond(net->A_Z_pilot);
 260
 261     net->num_engines = htonl(net->num_engines);
 262     for ( i = 0; i < net->num_engines; ++i ) {
 263         htonl(net->eng_state[i]);
 264         htond(net->rpm[i]);
 265         htond(net->fuel_flow[i]);
 266         htond(net->EGT[i]);
 267         htond(net->oil_temp[i]);
 268         htond(net->oil_px[i]);
 269     }
 270
 271     net->num_tanks = htonl(net->num_tanks);
 272     for ( i = 0; i < net->num_tanks; ++i ) {
 273         htond(net->fuel_quantity[i]);
 274     }
 275
 276     net->num_wheels = htonl(net->num_wheels);
 277     // I don't need to convert the Wow flags, since they are one byte in size
 278     htond(net->flap_deflection);
 279
 280     net->cur_time = ntohl(net->cur_time);
 281     net->warp = ntohl(net->warp);
 282     htond(net->visibility);
 283
 284     if ( net->version == FG_NET_FDM_VERSION ) {
 285         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 286         // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
 287         //      << endl;
 288         cur_fdm_state->_updateGeodeticPosition( net->latitude,
 289                                                 net->longitude,
 290                                                 net->altitude
 291                                                   * SG_METER_TO_FEET );
 292         cur_fdm_state->_set_Euler_Angles( net->phi,
 293                                           net->theta,
 294                                           net->psi );
 295         cur_fdm_state->_set_Euler_Rates( net->phidot,
 296                                          net->thetadot,
 297                                          net->psidot );
 298         cur_fdm_state->_set_V_calibrated_kts( net->vcas );
 299         cur_fdm_state->_set_Climb_Rate( net->climb_rate );
 300         cur_fdm_state->_set_Velocities_Local( net->v_north,
 301                                               net->v_east,
 302                                               net->v_down );
 303         cur_fdm_state->_set_Velocities_Wind_Body( net->v_wind_body_north,
 304                                                   net->v_wind_body_east,
 305                                                   net->v_wind_body_down );
 306
 307         fgSetDouble( "/sim/alarms/stall-warning", net->stall_warning );
 308         cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
 309                                                net->A_Y_pilot,
 310                                                net->A_Z_pilot );
 311
 312         for ( i = 0; i < net->num_engines; ++i ) {
 313             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 314
 315             // node->setBoolValue("running", t->isRunning());
 316             // node->setBoolValue("cranking", t->isCranking());
 317
 318             // cout << net->eng_state[i] << endl;
 319             if ( net->eng_state[i] == 0 ) {
 320                 node->setBoolValue( "cranking", false );
 321                 node->setBoolValue( "running", false );
 322             } else if ( net->eng_state[i] == 1 ) {
 323                 node->setBoolValue( "cranking", true );
 324                 node->setBoolValue( "running", false );
 325             } else if ( net->eng_state[i] == 2 ) {
 326                 node->setBoolValue( "cranking", false );
 327                 node->setBoolValue( "running", true );
 328             }
 329
 330             node->setDoubleValue( "rpm", net->rpm[i] );
 331             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 332             node->setDoubleValue( "egt-degf", net->EGT[i] );
 333             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 334             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 335         }
 336
 337         for (i = 0; i < net->num_tanks; ++i ) {
 338             SGPropertyNode * node
 339                 = fgGetNode("/consumables/fuel/tank", i, true);
 340             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 341         }
 342
 343         for (i = 0; i < net->num_wheels; ++i ) {
 344             SGPropertyNode * node
 345                 = fgGetNode("/gear/gear", i, true);
 346             node->setDoubleValue("wow", net->wow[i] );
 347         }
 348
 349         fgSetDouble("/surface-positions/flap-pos-norm", net->flap_deflection);
 350         SGPropertyNode * node = fgGetNode("/controls", true);
 351         fgSetDouble("/surface-positions/elevator-pos-norm",
 352                     node->getDoubleValue( "elevator" ));
 353         fgSetDouble("/surface-positions/rudder-pos-norm",
 354                     node->getDoubleValue( "rudder" ));
 355         fgSetDouble("/surface-positions/left-aileron-pos-norm",
 356                     node->getDoubleValue( "aileron" ));
 357         fgSetDouble("/surface-positions/right-aileron-pos-norm",
 358                     -node->getDoubleValue( "aileron" ));
 359
 360         /* these are ignored for now  ... */
 361         /*
 362         if ( net->cur_time ) {
 363             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 364         }
 365
 366         globals->set_warp( net->warp );
 367         last_warp = net->warp;
 368         */
 369     } else {
 370         SG_LOG( SG_IO, SG_ALERT,
 371                 "Error: version mismatch in FGNetFDM2Props()" );
 372         SG_LOG( SG_IO, SG_ALERT,
 373                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 374         SG_LOG( SG_IO, SG_ALERT,
 375                 "\tNeeds to upgrade net_fdm.hxx and recompile." );
 376     }
 377 }
 378
 379
 380 // process work for this port
 381 bool FGNativeFDM::process() {
 382     SGIOChannel *io = get_io_channel();
 383     int length = sizeof(buf);
 384
 385     if ( get_direction() == SG_IO_OUT ) {
 386         // cout << "size of cur_fdm_state = " << length << endl;
 387         FGProps2NetFDM( &buf );
 388         if ( ! io->write( (char *)(& buf), length ) ) {
 389             SG_LOG( SG_IO, SG_ALERT, "Error writing data." );
 390             return false;
 391         }
 392     } else if ( get_direction() == SG_IO_IN ) {
 393         if ( io->get_type() == sgFileType ) {
 394             if ( io->read( (char *)(& buf), length ) == length ) {
 395                 SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 396                 FGNetFDM2Props( &buf );
 397             }
 398         } else {
 399             while ( io->read( (char *)(& buf), length ) == length ) {
 400                 SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 401                 FGNetFDM2Props( &buf );
 402             }
 403         }
 404     }
 405
 406     return true;
 407 }
 408
 409
 410 // close the channel
 411 bool FGNativeFDM::close() {
 412     SGIOChannel *io = get_io_channel();
 413
 414     set_enabled( false );
 415
 416     if ( ! io->close() ) {
 417         return false;
 418     }
 419
 420     return true;
 421 }