src/FDM/ExternalNet/ExternalNet.cxx

   1 // ExternalNet.hxx -- an net interface to an external flight dynamics model
   2 //
   3 // Written by Curtis Olson, started November 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 #include <simgear/debug/logstream.hxx>
  24 #include <simgear/io/lowlevel.hxx> // endian tests
  25
  26 #include <Main/fg_props.hxx>
  27
  28 #include "ExternalNet.hxx"
  29
  30
  31 // FreeBSD works better with this included last ... (?)
  32 #if defined(WIN32) && !defined(__CYGWIN__)
  33 #  include <windows.h>
  34 #else
  35 #  include <netinet/in.h>       // htonl() ntohl()
  36 #endif
  37
  38
  39 // The function htond is defined this way due to the way some
  40 // processors and OSes treat floating point values.  Some will raise
  41 // an exception whenever a "bad" floating point value is loaded into a
  42 // floating point register.  Solaris is notorious for this, but then
  43 // so is LynxOS on the PowerPC.  By translating the data in place,
  44 // there is no need to load a FP register with the "corruped" floating
  45 // point value.  By doing the BIG_ENDIAN test, I can optimize the
  46 // routine for big-endian processors so it can be as efficient as
  47 // possible
  48 static void htond (double &x)
  49 {
  50     if ( sgIsLittleEndian() ) {
  51         int    *Double_Overlay;
  52         int     Holding_Buffer;
  53
  54         Double_Overlay = (int *) &x;
  55         Holding_Buffer = Double_Overlay [0];
  56
  57         Double_Overlay [0] = htonl (Double_Overlay [1]);
  58         Double_Overlay [1] = htonl (Holding_Buffer);
  59     } else {
  60         return;
  61     }
  62 }
  63
  64
  65 static void global2net( FGNetCtrls *net ) {
  66     int i;
  67
  68     // fill in values
  69     SGPropertyNode * node = fgGetNode("/controls", true);
  70     net->version = FG_NET_CTRLS_VERSION;
  71     net->aileron = node->getDoubleValue( "aileron" );
  72     net->elevator = node->getDoubleValue( "elevator" );
  73     net->elevator_trim = node->getDoubleValue( "elevator-trim" );
  74     net->rudder = node->getDoubleValue( "rudder" );
  75     net->flaps = node->getDoubleValue( "flaps" );
  76     net->flaps_power
  77             = node->getDoubleValue( "/systems/electrical/outputs/flaps",
  78                                     1.0 ) >= 1.0;
  79     net->num_engines = FGNetCtrls::FG_MAX_ENGINES;
  80     for ( i = 0; i < FGNetCtrls::FG_MAX_ENGINES; ++i ) {
  81         net->throttle[i] = node->getDoubleValue( "throttle", 0.0 );
  82         net->mixture[i] = node->getDoubleValue( "mixture", 0.0 );
  83         net->fuel_pump_power[i]
  84             = node->getDoubleValue( "/systems/electrical/outputs/fuel-pump",
  85                                     1.0 ) >= 1.0;
  86         net->prop_advance[i] = node->getDoubleValue( "propeller-pitch", 0.0 );
  87         net->magnetos[i] = node->getIntValue( "magnetos", 0 );
  88         if ( i == 0 ) {
  89           // cout << "Magnetos -> " << node->getIntValue( "magnetos", 0 );
  90         }
  91         net->starter_power[i]
  92             = node->getDoubleValue( "/systems/electrical/outputs/starter",
  93                                     1.0 ) >= 1.0;
  94         if ( i == 0 ) {
  95           // cout << " Starter -> " << node->getIntValue( "stater", false )
  96           //      << endl;
  97         }
  98     }
  99     net->num_tanks = FGNetCtrls::FG_MAX_TANKS;
 100     for ( i = 0; i < FGNetCtrls::FG_MAX_TANKS; ++i ) {
 101         if ( node->getChild("fuel-selector", i) != 0 ) {
 102             net->fuel_selector[i]
 103                 = node->getChild("fuel-selector", i)->getDoubleValue();
 104         } else {
 105             net->fuel_selector[i] = false;
 106         }
 107     }
 108     net->num_wheels = FGNetCtrls::FG_MAX_WHEELS;
 109     for ( i = 0; i < FGNetCtrls::FG_MAX_WHEELS; ++i ) {
 110         if ( node->getChild("brakes", i) != 0 ) {
 111             if ( node->getChild("parking-brake")->getDoubleValue() > 0.0 ) {
 112                 net->brake[i] = 1.0;
 113            } else {
 114                 net->brake[i]
 115                     = node->getChild("brakes", i)->getDoubleValue();
 116             }
 117         } else {
 118             net->brake[i] = 0.0;
 119         }
 120     }
 121
 122     node = fgGetNode("/controls/switches", true);
 123     net->master_bat = node->getChild("master-bat")->getBoolValue();
 124     net->master_alt = node->getChild("master-alt")->getBoolValue();
 125     net->master_avionics = node->getChild("master-avionics")->getBoolValue();
 126
 127     net->wind_speed_kt = fgGetDouble("/environment/wind-speed-kt");
 128     net->wind_dir_deg = fgGetDouble("/environment/wind-from-heading-deg");
 129
 130     // cur_fdm_state->get_ground_elev_ft() is what we want ... this
 131     // reports the altitude of the aircraft.
 132     // "/environment/ground-elevation-m" reports the ground elevation
 133     // of the current view point which could change substantially if
 134     // the user is switching views.
 135     net->hground = cur_fdm_state->get_ground_elev_ft() * SG_FEET_TO_METER;
 136     net->magvar = fgGetDouble("/environment/magnetic-variation-deg");
 137     net->speedup = fgGetInt("/sim/speed-up");
 138     net->freeze = 0;
 139     if ( fgGetBool("/sim/freeze/master") ) {
 140         net->freeze |= 0x01;
 141     }
 142     if ( fgGetBool("/sim/freeze/position") ) {
 143         net->freeze |= 0x02;
 144     }
 145     if ( fgGetBool("/sim/freeze/fuel") ) {
 146         net->freeze |= 0x04;
 147     }
 148
 149     // convert to network byte order
 150     net->version = htonl(net->version);
 151     htond(net->aileron);
 152     htond(net->elevator);
 153     htond(net->elevator_trim);
 154     htond(net->rudder);
 155     htond(net->flaps);
 156     net->flaps_power = htonl(net->flaps_power);
 157     for ( i = 0; i < FGNetCtrls::FG_MAX_ENGINES; ++i ) {
 158         htond(net->throttle[i]);
 159         htond(net->mixture[i]);
 160         net->fuel_pump_power[i] = htonl(net->fuel_pump_power[i]);
 161         htond(net->prop_advance[i]);
 162         net->magnetos[i] = htonl(net->magnetos[i]);
 163         net->starter_power[i] = htonl(net->starter_power[i]);
 164     }
 165     net->num_engines = htonl(net->num_engines);
 166     for ( i = 0; i < FGNetCtrls::FG_MAX_TANKS; ++i ) {
 167         net->fuel_selector[i] = htonl(net->fuel_selector[i]);
 168     }
 169     net->num_tanks = htonl(net->num_tanks);
 170     for ( i = 0; i < FGNetCtrls::FG_MAX_WHEELS; ++i ) {
 171         htond(net->brake[i]);
 172     }
 173     net->num_wheels = htonl(net->num_wheels);
 174     net->gear_handle = htonl(net->gear_handle);
 175     net->master_bat = htonl(net->master_bat);
 176     net->master_alt = htonl(net->master_alt);
 177     net->master_avionics = htonl(net->master_avionics);
 178     htond(net->wind_speed_kt);
 179     htond(net->wind_dir_deg);
 180     htond(net->hground);
 181     htond(net->magvar);
 182     net->speedup = htonl(net->speedup);
 183     net->freeze = htonl(net->freeze);
 184 }
 185
 186
 187 static void net2global( FGNetFDM *net ) {
 188     int i;
 189
 190     // Convert to the net buffer from network format
 191     net->version = ntohl(net->version);
 192
 193     htond(net->longitude);
 194     htond(net->latitude);
 195     htond(net->altitude);
 196     htond(net->phi);
 197     htond(net->theta);
 198     htond(net->psi);
 199
 200     htond(net->phidot);
 201     htond(net->thetadot);
 202     htond(net->psidot);
 203     htond(net->vcas);
 204     htond(net->climb_rate);
 205     htond(net->v_north);
 206     htond(net->v_east);
 207     htond(net->v_down);
 208     htond(net->v_wind_body_north);
 209     htond(net->v_wind_body_east);
 210     htond(net->v_wind_body_down);
 211     htond(net->stall_warning);
 212
 213     htond(net->A_X_pilot);
 214     htond(net->A_Y_pilot);
 215     htond(net->A_Z_pilot);
 216
 217     net->num_engines = htonl(net->num_engines);
 218     for ( i = 0; i < net->num_engines; ++i ) {
 219         htonl(net->eng_state[i]);
 220         htond(net->rpm[i]);
 221         htond(net->fuel_flow[i]);
 222         htond(net->EGT[i]);
 223         htond(net->oil_temp[i]);
 224         htond(net->oil_px[i]);
 225     }
 226
 227     net->num_tanks = htonl(net->num_tanks);
 228     for ( i = 0; i < net->num_tanks; ++i ) {
 229         htond(net->fuel_quantity[i]);
 230     }
 231
 232     net->num_wheels = htonl(net->num_wheels);
 233     // I don't need to convert the Wow flags, since they are one byte in size
 234     htond(net->flap_deflection);
 235
 236     net->cur_time = ntohl(net->cur_time);
 237     net->warp = ntohl(net->warp);
 238     htond(net->visibility);
 239
 240     if ( net->version == FG_NET_FDM_VERSION ) {
 241         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 242         // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
 243         //      << endl;
 244         cur_fdm_state->_updateGeodeticPosition( net->latitude,
 245                                                 net->longitude,
 246                                                 net->altitude
 247                                                   * SG_METER_TO_FEET );
 248         cur_fdm_state->_set_Euler_Angles( net->phi,
 249                                           net->theta,
 250                                           net->psi );
 251         cur_fdm_state->_set_Euler_Rates( net->phidot,
 252                                          net->thetadot,
 253                                          net->psidot );
 254         cur_fdm_state->_set_V_calibrated_kts( net->vcas );
 255         cur_fdm_state->_set_Climb_Rate( net->climb_rate );
 256         cur_fdm_state->_set_Velocities_Local( net->v_north,
 257                                               net->v_east,
 258                                               net->v_down );
 259         cur_fdm_state->_set_Velocities_Wind_Body( net->v_wind_body_north,
 260                                                   net->v_wind_body_east,
 261                                                   net->v_wind_body_down );
 262
 263         fgSetDouble( "/sim/alarms/stall-warning", net->stall_warning );
 264         cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
 265                                                net->A_Y_pilot,
 266                                                net->A_Z_pilot );
 267
 268         for ( i = 0; i < net->num_engines; ++i ) {
 269             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 270
 271             // node->setBoolValue("running", t->isRunning());
 272             // node->setBoolValue("cranking", t->isCranking());
 273
 274             // cout << net->eng_state[i] << endl;
 275             if ( net->eng_state[i] == 0 ) {
 276                 node->setBoolValue( "cranking", false );
 277                 node->setBoolValue( "running", false );
 278             } else if ( net->eng_state[i] == 1 ) {
 279                 node->setBoolValue( "cranking", true );
 280                 node->setBoolValue( "running", false );
 281             } else if ( net->eng_state[i] == 2 ) {
 282                 node->setBoolValue( "cranking", false );
 283                 node->setBoolValue( "running", true );
 284             }
 285
 286             node->setDoubleValue( "rpm", net->rpm[i] );
 287             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 288             node->setDoubleValue( "egt-degf", net->EGT[i] );
 289             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 290             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 291         }
 292
 293         for (i = 0; i < net->num_tanks; ++i ) {
 294             SGPropertyNode * node
 295                 = fgGetNode("/consumables/fuel/tank", i, true);
 296             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 297         }
 298
 299         for (i = 0; i < net->num_wheels; ++i ) {
 300             SGPropertyNode * node
 301                 = fgGetNode("/gear/gear", i, true);
 302             node->setDoubleValue("wow", net->wow[i] );
 303         }
 304
 305         fgSetDouble("/surface-positions/flap-pos-norm", net->flap_deflection);
 306         SGPropertyNode * node = fgGetNode("/controls", true);
 307         fgSetDouble("/surface-positions/elevator-pos-norm",
 308                     node->getDoubleValue( "elevator" ));
 309         fgSetDouble("/surface-positions/rudder-pos-norm",
 310                     node->getDoubleValue( "rudder" ));
 311         fgSetDouble("/surface-positions/left-aileron-pos-norm",
 312                     node->getDoubleValue( "aileron" ));
 313         fgSetDouble("/surface-positions/right-aileron-pos-norm",
 314                     -node->getDoubleValue( "aileron" ));
 315
 316         /* these are ignored for now  ... */
 317         /*
 318         if ( net->cur_time ) {
 319             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 320         }
 321
 322         globals->set_warp( net->warp );
 323         last_warp = net->warp;
 324         */
 325     } else {
 326         SG_LOG( SG_IO, SG_ALERT, "Error: version mismatch in net2global()" );
 327         SG_LOG( SG_IO, SG_ALERT,
 328                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 329         SG_LOG( SG_IO, SG_ALERT,
 330                 "\tsomeone needs to upgrade net_fdm.hxx and recompile." );
 331     }
 332 }
 333
 334
 335 FGExternalNet::FGExternalNet( double dt, string host, int dop, int dip, int cp )
 336 {
 337 //     set_delta_t( dt );
 338
 339     valid = true;
 340
 341     data_in_port = dip;
 342     data_out_port = dop;
 343     cmd_port = cp;
 344     fdm_host = host;
 345
 346     /////////////////////////////////////////////////////////
 347     // Setup client udp connection (sends data to remote fdm)
 348
 349     if ( ! data_client.open( false ) ) {
 350         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client data channel" );
 351         valid = false;
 352     }
 353
 354     // fire and forget
 355     data_client.setBlocking( false );
 356
 357     if ( data_client.connect( fdm_host.c_str(), data_out_port ) == -1 ) {
 358         printf("error connecting to %s:%d\n", fdm_host.c_str(), data_out_port);
 359         valid = false;
 360     }
 361
 362     /////////////////////////////////////////////////////////
 363     // Setup server udp connection (for receiving data)
 364
 365     if ( ! data_server.open( false ) ) {
 366         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client server channel" );
 367         valid = false;
 368     }
 369
 370     // disable blocking
 371     data_server.setBlocking( false );
 372
 373     // allowed to read from a broadcast addr
 374     // data_server.setBroadcast( true );
 375
 376     // if we bind to fdm_host = "" then we accept messages from
 377     // anyone.
 378     if ( data_server.bind( "", data_in_port ) == -1 ) {
 379         printf("error binding to port %d\n", data_in_port);
 380         valid = false;
 381     }
 382 }
 383
 384
 385 FGExternalNet::~FGExternalNet() {
 386     data_client.close();
 387     data_server.close();
 388 }
 389
 390
 391 // Initialize the ExternalNet flight model, dt is the time increment
 392 // for each subsequent iteration through the EOM
 393 void FGExternalNet::init() {
 394     // cout << "FGExternalNet::init()" << endl;
 395
 396     // Explicitly call the superclass's
 397     // init method first.
 398     common_init();
 399
 400     double lon = fgGetDouble( "/sim/presets/longitude-deg" );
 401     double lat = fgGetDouble( "/sim/presets/latitude-deg" );
 402     double alt = fgGetDouble( "/sim/presets/altitude-ft" );
 403     double ground = fgGetDouble( "/environment/ground-elevation-m" );
 404     double heading = fgGetDouble("/sim/presets/heading-deg");
 405     double speed = fgGetDouble( "/sim/presets/airspeed-kt" );
 406
 407     char cmd[256];
 408
 409     HTTPClient *http;
 410     sprintf( cmd, "/longitude-deg?value=%.8f", lon );
 411     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 412     while ( !http->isDone(1000000) ) http->poll(0);
 413     delete http;
 414
 415     sprintf( cmd, "/latitude-deg?value=%.8f", lat );
 416     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 417     while ( !http->isDone(1000000) ) http->poll(0);
 418     delete http;
 419
 420     sprintf( cmd, "/altitude-ft?value=%.8f", alt );
 421     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 422     while ( !http->isDone(1000000) ) http->poll(0);
 423     delete http;
 424
 425     sprintf( cmd, "/ground-m?value=%.8f", ground );
 426     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 427     while ( !http->isDone(1000000) ) http->poll(0);
 428     delete http;
 429
 430     sprintf( cmd, "/speed-kts?value=%.8f", speed );
 431     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 432     while ( !http->isDone(1000000) ) http->poll(0);
 433     delete http;
 434
 435     sprintf( cmd, "/heading-deg?value=%.8f", heading );
 436     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 437     while ( !http->isDone(1000000) ) http->poll(0);
 438     delete http;
 439
 440     SG_LOG( SG_IO, SG_INFO, "before sending reset command." );
 441
 442     if( fgGetBool("/sim/presets/onground") ) {
 443       sprintf( cmd, "/reset?value=ground" );
 444     } else {
 445       sprintf( cmd, "/reset?value=air" );
 446     }
 447     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 448     while ( !http->isDone(1000000) ) http->poll(0);
 449     delete http;
 450
 451     SG_LOG( SG_IO, SG_INFO, "Remote FDM init() finished." );
 452 }
 453
 454
 455 // Run an iteration of the EOM.
 456 void FGExternalNet::update( double dt ) {
 457     int length;
 458     int result;
 459
 460     if (is_suspended())
 461       return;
 462
 463     // Send control positions to remote fdm
 464     length = sizeof(ctrls);
 465     global2net( &ctrls );
 466     if ( data_client.send( (char *)(& ctrls), length, 0 ) != length ) {
 467         SG_LOG( SG_IO, SG_DEBUG, "Error writing data." );
 468     } else {
 469         SG_LOG( SG_IO, SG_DEBUG, "wrote control data." );
 470     }
 471
 472     // Read next set of FDM data (blocking enabled to maintain 'sync')
 473     length = sizeof(fdm);
 474     while ( (result = data_server.recv( (char *)(& fdm), length, 0)) >= 0 ) {
 475         SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 476         net2global( &fdm );
 477     }
 478 }