src/FDM/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 global2raw( FGRawCtrls *raw ) {
  66     int i;
  67
  68     // fill in values
  69     SGPropertyNode * node = fgGetNode("/controls", true);
  70     raw->version = FG_RAW_CTRLS_VERSION;
  71     raw->aileron = node->getDoubleValue( "aileron" );
  72     raw->elevator = node->getDoubleValue( "elevator" );
  73     raw->elevator_trim = node->getDoubleValue( "elevator-trim" );
  74     raw->rudder = node->getDoubleValue( "rudder" );
  75     raw->flaps = node->getDoubleValue( "flaps" );
  76     raw->flaps_power
  77             = node->getDoubleValue( "/systems/electrical/outputs/flaps",
  78                                     1.0 ) >= 1.0;
  79     raw->num_engines = FGRawCtrls::FG_MAX_ENGINES;
  80     for ( i = 0; i < FGRawCtrls::FG_MAX_ENGINES; ++i ) {
  81         raw->throttle[i] = node->getDoubleValue( "throttle", 0.0 );
  82         raw->mixture[i] = node->getDoubleValue( "mixture", 0.0 );
  83         raw->fuel_pump_power[i]
  84             = node->getDoubleValue( "/systems/electrical/outputs/fuel-pump",
  85                                     1.0 ) >= 1.0;
  86         raw->prop_advance[i] = node->getDoubleValue( "propeller-pitch", 0.0 );
  87         raw->magnetos[i] = node->getIntValue( "magnetos", 0 );
  88         if ( i == 0 ) {
  89           // cout << "Magnetos -> " << node->getIntValue( "magnetos", 0 );
  90         }
  91         raw->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     raw->num_tanks = FGRawCtrls::FG_MAX_TANKS;
 100     for ( i = 0; i < FGRawCtrls::FG_MAX_TANKS; ++i ) {
 101         if ( node->getChild("fuel-selector", i) != 0 ) {
 102             raw->fuel_selector[i]
 103                 = node->getChild("fuel-selector", i)->getDoubleValue();
 104         } else {
 105             raw->fuel_selector[i] = false;
 106         }
 107     }
 108     raw->num_wheels = FGRawCtrls::FG_MAX_WHEELS;
 109     for ( i = 0; i < FGRawCtrls::FG_MAX_WHEELS; ++i ) {
 110         if ( node->getChild("brakes", i) != 0 ) {
 111             raw->brake[i]
 112                 = node->getChild("brakes", i)->getDoubleValue();
 113         } else {
 114             raw->brake[i] = 0.0;
 115         }
 116     }
 117
 118     node = fgGetNode("/controls/switches", true);
 119     raw->master_bat = node->getChild("master-bat")->getBoolValue();
 120     raw->master_alt = node->getChild("master-alt")->getBoolValue();
 121     raw->master_avionics = node->getChild("master-avionics")->getBoolValue();
 122
 123     raw->hground = fgGetDouble( "/environment/ground-elevation-m" );
 124     raw->magvar = fgGetDouble("/environment/magnetic-variation-deg");
 125     raw->speedup = fgGetInt("/sim/speed-up");
 126
 127     // convert to network byte order
 128     raw->version = htonl(raw->version);
 129     htond(raw->aileron);
 130     htond(raw->elevator);
 131     htond(raw->elevator_trim);
 132     htond(raw->rudder);
 133     htond(raw->flaps);
 134     raw->flaps_power = htonl(raw->flaps_power);
 135     for ( i = 0; i < FGRawCtrls::FG_MAX_ENGINES; ++i ) {
 136         htond(raw->throttle[i]);
 137         htond(raw->mixture[i]);
 138         raw->fuel_pump_power[i] = htonl(raw->fuel_pump_power[i]);
 139         htond(raw->prop_advance[i]);
 140         raw->magnetos[i] = htonl(raw->magnetos[i]);
 141         raw->starter_power[i] = htonl(raw->starter_power[i]);
 142     }
 143     raw->num_engines = htonl(raw->num_engines);
 144     for ( i = 0; i < FGRawCtrls::FG_MAX_TANKS; ++i ) {
 145         raw->fuel_selector[i] = htonl(raw->fuel_selector[i]);
 146     }
 147     raw->num_tanks = htonl(raw->num_tanks);
 148     for ( i = 0; i < FGRawCtrls::FG_MAX_WHEELS; ++i ) {
 149         htond(raw->brake[i]);
 150     }
 151     raw->num_wheels = htonl(raw->num_wheels);
 152     raw->gear_handle = htonl(raw->gear_handle);
 153     raw->master_bat = htonl(raw->master_bat);
 154     raw->master_alt = htonl(raw->master_alt);
 155     raw->master_avionics = htonl(raw->master_avionics);
 156     htond(raw->hground);
 157     htond(raw->magvar);
 158     raw->speedup = htonl(raw->speedup);
 159 }
 160
 161
 162 static void net2global( FGNetFDM *net ) {
 163     int i;
 164
 165     // Convert to the net buffer from network format
 166     net->version = ntohl(net->version);
 167
 168     htond(net->longitude);
 169     htond(net->latitude);
 170     htond(net->altitude);
 171     htond(net->phi);
 172     htond(net->theta);
 173     htond(net->psi);
 174
 175     htond(net->phidot);
 176     htond(net->thetadot);
 177     htond(net->psidot);
 178     htond(net->vcas);
 179     htond(net->climb_rate);
 180     htond(net->v_north);
 181     htond(net->v_east);
 182     htond(net->v_down);
 183
 184     htond(net->A_X_pilot);
 185     htond(net->A_Y_pilot);
 186     htond(net->A_Z_pilot);
 187
 188     net->num_engines = htonl(net->num_engines);
 189     for ( i = 0; i < net->num_engines; ++i ) {
 190         htonl(net->eng_state[i]);
 191         htond(net->rpm[i]);
 192         htond(net->fuel_flow[i]);
 193         htond(net->EGT[i]);
 194         htond(net->oil_temp[i]);
 195         htond(net->oil_px[i]);
 196     }
 197
 198     net->num_tanks = htonl(net->num_tanks);
 199     for ( i = 0; i < net->num_tanks; ++i ) {
 200         htond(net->fuel_quantity[i]);
 201     }
 202
 203     net->num_wheels = htonl(net->num_wheels);
 204     // I don't need to convert the Wow flags, since they are one byte in size
 205     htond(net->flap_deflection);
 206
 207     net->cur_time = ntohl(net->cur_time);
 208     net->warp = ntohl(net->warp);
 209     htond(net->visibility);
 210
 211     if ( net->version == FG_NET_FDM_VERSION ) {
 212         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 213         // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
 214         //      << endl;
 215         cur_fdm_state->_updateGeodeticPosition( net->latitude,
 216                                                 net->longitude,
 217                                                 net->altitude
 218                                                   * SG_METER_TO_FEET );
 219         cur_fdm_state->_set_Euler_Angles( net->phi,
 220                                           net->theta,
 221                                           net->psi );
 222         cur_fdm_state->_set_Euler_Rates( net->phidot,
 223                                          net->thetadot,
 224                                          net->psidot );
 225         cur_fdm_state->_set_V_calibrated_kts( net->vcas );
 226         cur_fdm_state->_set_Climb_Rate( net->climb_rate );
 227         cur_fdm_state->_set_Velocities_Local( net->v_north,
 228                                               net->v_east,
 229                                               net->v_down );
 230         cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
 231                                                net->A_Y_pilot,
 232                                                net->A_Z_pilot );
 233
 234         for ( i = 0; i < net->num_engines; ++i ) {
 235             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 236
 237             // node->setBoolValue("running", t->isRunning());
 238             // node->setBoolValue("cranking", t->isCranking());
 239
 240             // cout << net->eng_state[i] << endl;
 241             if ( net->eng_state[i] == 0 ) {
 242                 node->setBoolValue( "cranking", false );
 243                 node->setBoolValue( "running", false );
 244             } else if ( net->eng_state[i] == 1 ) {
 245                 node->setBoolValue( "cranking", true );
 246                 node->setBoolValue( "running", false );
 247             } else if ( net->eng_state[i] == 2 ) {
 248                 node->setBoolValue( "cranking", false );
 249                 node->setBoolValue( "running", true );
 250             }
 251
 252             node->setDoubleValue( "rpm", net->rpm[i] );
 253             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 254             node->setDoubleValue( "egt-degf", net->EGT[i] );
 255             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 256             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 257         }
 258
 259         for (i = 0; i < net->num_tanks; ++i ) {
 260             SGPropertyNode * node
 261                 = fgGetNode("/consumables/fuel/tank", i, true);
 262             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 263         }
 264
 265         for (i = 0; i < net->num_wheels; ++i ) {
 266             SGPropertyNode * node
 267                 = fgGetNode("/gear/gear", i, true);
 268             node->setDoubleValue("wow", net->wow[i] );
 269         }
 270
 271         fgSetDouble("/surface-positions/flap-pos-norm", net->flap_deflection);
 272         SGPropertyNode * node = fgGetNode("/controls", true);
 273         fgSetDouble("/surface-positions/elevator-pos-norm",
 274                     node->getDoubleValue( "elevator" ));
 275         fgSetDouble("/surface-positions/rudder-pos-norm",
 276                     node->getDoubleValue( "rudder" ));
 277         fgSetDouble("/surface-positions/left-aileron-pos-norm",
 278                     node->getDoubleValue( "aileron" ));
 279         fgSetDouble("/surface-positions/right-aileron-pos-norm",
 280                     -node->getDoubleValue( "aileron" ));
 281
 282         /* these are ignored for now  ... */
 283         /*
 284         if ( net->cur_time ) {
 285             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 286         }
 287
 288         globals->set_warp( net->warp );
 289         last_warp = net->warp;
 290         */
 291     } else {
 292         SG_LOG( SG_IO, SG_ALERT, "Error: version mismatch in net2global()" );
 293         SG_LOG( SG_IO, SG_ALERT,
 294                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 295         SG_LOG( SG_IO, SG_ALERT,
 296                 "\tsomeone needs to upgrade net_fdm.hxx and recompile." );
 297     }
 298 }
 299
 300
 301 FGExternalNet::FGExternalNet( double dt, string host, int dop, int dip, int cp )
 302 {
 303 //     set_delta_t( dt );
 304
 305     valid = true;
 306
 307     data_in_port = dip;
 308     data_out_port = dop;
 309     cmd_port = cp;
 310     fdm_host = host;
 311
 312     /////////////////////////////////////////////////////////
 313     // Setup client udp connection (sends data to remote fdm)
 314
 315     if ( ! data_client.open( false ) ) {
 316         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client data channel" );
 317         valid = false;
 318     }
 319
 320     // fire and forget
 321     data_client.setBlocking( false );
 322
 323     if ( data_client.connect( fdm_host.c_str(), data_out_port ) == -1 ) {
 324         printf("error connecting to %s:%d\n", fdm_host.c_str(), data_out_port);
 325         valid = false;
 326     }
 327
 328     /////////////////////////////////////////////////////////
 329     // Setup server udp connection (for receiving data)
 330
 331     if ( ! data_server.open( false ) ) {
 332         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client server channel" );
 333         valid = false;
 334     }
 335
 336     // disable blocking
 337     data_server.setBlocking( false );
 338
 339     // allowed to read from a broadcast addr
 340     // data_server.setBroadcast( true );
 341
 342     // if we bind to fdm_host = "" then we accept messages from
 343     // anyone.
 344     if ( data_server.bind( "", data_in_port ) == -1 ) {
 345         printf("error binding to port %d\n", data_in_port);
 346         valid = false;
 347     }
 348 }
 349
 350
 351 FGExternalNet::~FGExternalNet() {
 352     data_client.close();
 353     data_server.close();
 354 }
 355
 356
 357 // Initialize the ExternalNet flight model, dt is the time increment
 358 // for each subsequent iteration through the EOM
 359 void FGExternalNet::init() {
 360     // cout << "FGExternalNet::init()" << endl;
 361
 362     // Explicitly call the superclass's
 363     // init method first.
 364     common_init();
 365
 366     double lon = fgGetDouble( "/position/longitude-deg" );
 367     double lat = fgGetDouble( "/position/latitude-deg" );
 368     double ground = fgGetDouble( "/environment/ground-elevation-m" );
 369     double heading = fgGetDouble("/orientation/heading-deg");
 370
 371     char cmd[256];
 372
 373     sprintf( cmd, "/longitude-deg?value=%.8f", lon );
 374     new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 375 //     cout << "before loop()" << endl;
 376     netChannel::loop(0);
 377 //     cout << "here" << endl;
 378
 379     sprintf( cmd, "/latitude-deg?value=%.8f", lat );
 380     new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 381     netChannel::loop(0);
 382
 383     sprintf( cmd, "/ground-m?value=%.8f", ground );
 384     new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 385     netChannel::loop(0);
 386
 387     sprintf( cmd, "/heading-deg?value=%.8f", heading );
 388     new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 389     netChannel::loop(0);
 390
 391     SG_LOG( SG_IO, SG_INFO, "before sending reset command." );
 392
 393     sprintf( cmd, "/reset?value=ground" );
 394     new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 395     netChannel::loop(0);
 396
 397     SG_LOG( SG_IO, SG_INFO, "Remote FDM init() finished." );
 398 }
 399
 400
 401 // Run an iteration of the EOM.
 402 void FGExternalNet::update( double dt ) {
 403     int length;
 404     int result;
 405
 406     if (is_suspended())
 407       return;
 408
 409     // Send control positions to remote fdm
 410     length = sizeof(ctrls);
 411     global2raw( &ctrls );
 412     if ( data_client.send( (char *)(& ctrls), length, 0 ) != length ) {
 413         SG_LOG( SG_IO, SG_DEBUG, "Error writing data." );
 414     } else {
 415         SG_LOG( SG_IO, SG_DEBUG, "wrote control data." );
 416     }
 417
 418     // Read next set of FDM data (blocking enabled to maintain 'sync')
 419     length = sizeof(fdm);
 420     while ( (result = data_server.recv( (char *)(& fdm), length, 0)) >= 0 ) {
 421         SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 422         net2global( &fdm );
 423     }
 424 }