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             net->brake[i]
 112                 = node->getChild("brakes", i)->getDoubleValue();
 113         } else {
 114             net->brake[i] = 0.0;
 115         }
 116     }
 117
 118     node = fgGetNode("/controls/switches", true);
 119     net->master_bat = node->getChild("master-bat")->getBoolValue();
 120     net->master_alt = node->getChild("master-alt")->getBoolValue();
 121     net->master_avionics = node->getChild("master-avionics")->getBoolValue();
 122
 123     // cur_fdm_state->get_ground_elev_ft() is what we want ... this
 124     // reports the altitude of the aircraft.
 125     // "/environment/ground-elevation-m" reports the ground elevation
 126     // of the current view point which could change substantially if
 127     // the user is switching views.
 128     net->hground = cur_fdm_state->get_ground_elev_ft() * SG_FEET_TO_METER;
 129     net->magvar = fgGetDouble("/environment/magnetic-variation-deg");
 130     net->speedup = fgGetInt("/sim/speed-up");
 131
 132     // convert to network byte order
 133     net->version = htonl(net->version);
 134     htond(net->aileron);
 135     htond(net->elevator);
 136     htond(net->elevator_trim);
 137     htond(net->rudder);
 138     htond(net->flaps);
 139     net->flaps_power = htonl(net->flaps_power);
 140     for ( i = 0; i < FGNetCtrls::FG_MAX_ENGINES; ++i ) {
 141         htond(net->throttle[i]);
 142         htond(net->mixture[i]);
 143         net->fuel_pump_power[i] = htonl(net->fuel_pump_power[i]);
 144         htond(net->prop_advance[i]);
 145         net->magnetos[i] = htonl(net->magnetos[i]);
 146         net->starter_power[i] = htonl(net->starter_power[i]);
 147     }
 148     net->num_engines = htonl(net->num_engines);
 149     for ( i = 0; i < FGNetCtrls::FG_MAX_TANKS; ++i ) {
 150         net->fuel_selector[i] = htonl(net->fuel_selector[i]);
 151     }
 152     net->num_tanks = htonl(net->num_tanks);
 153     for ( i = 0; i < FGNetCtrls::FG_MAX_WHEELS; ++i ) {
 154         htond(net->brake[i]);
 155     }
 156     net->num_wheels = htonl(net->num_wheels);
 157     net->gear_handle = htonl(net->gear_handle);
 158     net->master_bat = htonl(net->master_bat);
 159     net->master_alt = htonl(net->master_alt);
 160     net->master_avionics = htonl(net->master_avionics);
 161     htond(net->hground);
 162     htond(net->magvar);
 163     net->speedup = htonl(net->speedup);
 164 }
 165
 166
 167 static void net2global( FGNetFDM *net ) {
 168     int i;
 169
 170     // Convert to the net buffer from network format
 171     net->version = ntohl(net->version);
 172
 173     htond(net->longitude);
 174     htond(net->latitude);
 175     htond(net->altitude);
 176     htond(net->phi);
 177     htond(net->theta);
 178     htond(net->psi);
 179
 180     htond(net->phidot);
 181     htond(net->thetadot);
 182     htond(net->psidot);
 183     htond(net->vcas);
 184     htond(net->climb_rate);
 185     htond(net->v_north);
 186     htond(net->v_east);
 187     htond(net->v_down);
 188     htond(net->stall_warning);
 189
 190     htond(net->A_X_pilot);
 191     htond(net->A_Y_pilot);
 192     htond(net->A_Z_pilot);
 193
 194     net->num_engines = htonl(net->num_engines);
 195     for ( i = 0; i < net->num_engines; ++i ) {
 196         htonl(net->eng_state[i]);
 197         htond(net->rpm[i]);
 198         htond(net->fuel_flow[i]);
 199         htond(net->EGT[i]);
 200         htond(net->oil_temp[i]);
 201         htond(net->oil_px[i]);
 202     }
 203
 204     net->num_tanks = htonl(net->num_tanks);
 205     for ( i = 0; i < net->num_tanks; ++i ) {
 206         htond(net->fuel_quantity[i]);
 207     }
 208
 209     net->num_wheels = htonl(net->num_wheels);
 210     // I don't need to convert the Wow flags, since they are one byte in size
 211     htond(net->flap_deflection);
 212
 213     net->cur_time = ntohl(net->cur_time);
 214     net->warp = ntohl(net->warp);
 215     htond(net->visibility);
 216
 217     if ( net->version == FG_NET_FDM_VERSION ) {
 218         // cout << "pos = " << net->longitude << " " << net->latitude << endl;
 219         // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
 220         //      << endl;
 221         cur_fdm_state->_updateGeodeticPosition( net->latitude,
 222                                                 net->longitude,
 223                                                 net->altitude
 224                                                   * SG_METER_TO_FEET );
 225         cur_fdm_state->_set_Euler_Angles( net->phi,
 226                                           net->theta,
 227                                           net->psi );
 228         cur_fdm_state->_set_Euler_Rates( net->phidot,
 229                                          net->thetadot,
 230                                          net->psidot );
 231         cur_fdm_state->_set_V_calibrated_kts( net->vcas );
 232         cur_fdm_state->_set_Climb_Rate( net->climb_rate );
 233         cur_fdm_state->_set_Velocities_Local( net->v_north,
 234                                               net->v_east,
 235                                               net->v_down );
 236         fgSetDouble( "/sim/aero/alarms/stall-warning", net->stall_warning );
 237         cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
 238                                                net->A_Y_pilot,
 239                                                net->A_Z_pilot );
 240
 241         for ( i = 0; i < net->num_engines; ++i ) {
 242             SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
 243
 244             // node->setBoolValue("running", t->isRunning());
 245             // node->setBoolValue("cranking", t->isCranking());
 246
 247             // cout << net->eng_state[i] << endl;
 248             if ( net->eng_state[i] == 0 ) {
 249                 node->setBoolValue( "cranking", false );
 250                 node->setBoolValue( "running", false );
 251             } else if ( net->eng_state[i] == 1 ) {
 252                 node->setBoolValue( "cranking", true );
 253                 node->setBoolValue( "running", false );
 254             } else if ( net->eng_state[i] == 2 ) {
 255                 node->setBoolValue( "cranking", false );
 256                 node->setBoolValue( "running", true );
 257             }
 258
 259             node->setDoubleValue( "rpm", net->rpm[i] );
 260             node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
 261             node->setDoubleValue( "egt-degf", net->EGT[i] );
 262             node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
 263             node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
 264         }
 265
 266         for (i = 0; i < net->num_tanks; ++i ) {
 267             SGPropertyNode * node
 268                 = fgGetNode("/consumables/fuel/tank", i, true);
 269             node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
 270         }
 271
 272         for (i = 0; i < net->num_wheels; ++i ) {
 273             SGPropertyNode * node
 274                 = fgGetNode("/gear/gear", i, true);
 275             node->setDoubleValue("wow", net->wow[i] );
 276         }
 277
 278         fgSetDouble("/surface-positions/flap-pos-norm", net->flap_deflection);
 279         SGPropertyNode * node = fgGetNode("/controls", true);
 280         fgSetDouble("/surface-positions/elevator-pos-norm",
 281                     node->getDoubleValue( "elevator" ));
 282         fgSetDouble("/surface-positions/rudder-pos-norm",
 283                     node->getDoubleValue( "rudder" ));
 284         fgSetDouble("/surface-positions/left-aileron-pos-norm",
 285                     node->getDoubleValue( "aileron" ));
 286         fgSetDouble("/surface-positions/right-aileron-pos-norm",
 287                     -node->getDoubleValue( "aileron" ));
 288
 289         /* these are ignored for now  ... */
 290         /*
 291         if ( net->cur_time ) {
 292             fgSetLong("/sim/time/cur-time-override", net->cur_time);
 293         }
 294
 295         globals->set_warp( net->warp );
 296         last_warp = net->warp;
 297         */
 298     } else {
 299         SG_LOG( SG_IO, SG_ALERT, "Error: version mismatch in net2global()" );
 300         SG_LOG( SG_IO, SG_ALERT,
 301                 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
 302         SG_LOG( SG_IO, SG_ALERT,
 303                 "\tsomeone needs to upgrade net_fdm.hxx and recompile." );
 304     }
 305 }
 306
 307
 308 FGExternalNet::FGExternalNet( double dt, string host, int dop, int dip, int cp )
 309 {
 310 //     set_delta_t( dt );
 311
 312     valid = true;
 313
 314     data_in_port = dip;
 315     data_out_port = dop;
 316     cmd_port = cp;
 317     fdm_host = host;
 318
 319     /////////////////////////////////////////////////////////
 320     // Setup client udp connection (sends data to remote fdm)
 321
 322     if ( ! data_client.open( false ) ) {
 323         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client data channel" );
 324         valid = false;
 325     }
 326
 327     // fire and forget
 328     data_client.setBlocking( false );
 329
 330     if ( data_client.connect( fdm_host.c_str(), data_out_port ) == -1 ) {
 331         printf("error connecting to %s:%d\n", fdm_host.c_str(), data_out_port);
 332         valid = false;
 333     }
 334
 335     /////////////////////////////////////////////////////////
 336     // Setup server udp connection (for receiving data)
 337
 338     if ( ! data_server.open( false ) ) {
 339         SG_LOG( SG_FLIGHT, SG_ALERT, "Error opening client server channel" );
 340         valid = false;
 341     }
 342
 343     // disable blocking
 344     data_server.setBlocking( false );
 345
 346     // allowed to read from a broadcast addr
 347     // data_server.setBroadcast( true );
 348
 349     // if we bind to fdm_host = "" then we accept messages from
 350     // anyone.
 351     if ( data_server.bind( "", data_in_port ) == -1 ) {
 352         printf("error binding to port %d\n", data_in_port);
 353         valid = false;
 354     }
 355 }
 356
 357
 358 FGExternalNet::~FGExternalNet() {
 359     data_client.close();
 360     data_server.close();
 361 }
 362
 363
 364 // Initialize the ExternalNet flight model, dt is the time increment
 365 // for each subsequent iteration through the EOM
 366 void FGExternalNet::init() {
 367     // cout << "FGExternalNet::init()" << endl;
 368
 369     // Explicitly call the superclass's
 370     // init method first.
 371     common_init();
 372
 373     double lon = fgGetDouble( "/position/longitude-deg" );
 374     double lat = fgGetDouble( "/position/latitude-deg" );
 375     double ground = fgGetDouble( "/environment/ground-elevation-m" );
 376     double heading = fgGetDouble("/orientation/heading-deg");
 377
 378     char cmd[256];
 379
 380     HTTPClient *http;
 381     sprintf( cmd, "/longitude-deg?value=%.8f", lon );
 382     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 383     while ( !http->isDone() ) http->poll(0);
 384     delete http;
 385
 386     sprintf( cmd, "/latitude-deg?value=%.8f", lat );
 387     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 388     while ( !http->isDone() ) http->poll(0);
 389     delete http;
 390
 391     sprintf( cmd, "/ground-m?value=%.8f", ground );
 392     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 393     while ( !http->isDone() ) http->poll(0);
 394     delete http;
 395
 396     sprintf( cmd, "/heading-deg?value=%.8f", heading );
 397     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 398     while ( !http->isDone() ) http->poll(0);
 399     delete http;
 400
 401     SG_LOG( SG_IO, SG_INFO, "before sending reset command." );
 402
 403     sprintf( cmd, "/reset?value=ground" );
 404     http = new HTTPClient( fdm_host.c_str(), cmd_port, cmd );
 405     while ( !http->isDone() ) http->poll(0);
 406     delete http;
 407
 408     SG_LOG( SG_IO, SG_INFO, "Remote FDM init() finished." );
 409 }
 410
 411
 412 // Run an iteration of the EOM.
 413 void FGExternalNet::update( double dt ) {
 414     int length;
 415     int result;
 416
 417     if (is_suspended())
 418       return;
 419
 420     // Send control positions to remote fdm
 421     length = sizeof(ctrls);
 422     global2net( &ctrls );
 423     if ( data_client.send( (char *)(& ctrls), length, 0 ) != length ) {
 424         SG_LOG( SG_IO, SG_DEBUG, "Error writing data." );
 425     } else {
 426         SG_LOG( SG_IO, SG_DEBUG, "wrote control data." );
 427     }
 428
 429     // Read next set of FDM data (blocking enabled to maintain 'sync')
 430     length = sizeof(fdm);
 431     while ( (result = data_server.recv( (char *)(& fdm), length, 0)) >= 0 ) {
 432         SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
 433         net2global( &fdm );
 434     }
 435 }