1 // native_fdm.cxx -- FGFS "Native" flight dynamics protocal class
3 // Written by Curtis Olson, started September 2001.
5 // Copyright (C) 2001 Curtis L. Olson - curt@flightgear.org
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.
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.
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.
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>
33 #include <FDM/flight.hxx>
34 #include <Time/tmp.hxx>
35 #include <Main/fg_props.hxx>
36 #include <Main/globals.hxx>
38 #include "native_fdm.hxx"
40 // FreeBSD works better with this included last ... (?)
41 #if defined(WIN32) && !defined(__CYGWIN__)
44 # include <netinet/in.h> // htonl() ntohl()
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
57 static void htond (double &x)
59 if ( sgIsLittleEndian() ) {
63 Double_Overlay = (int *) &x;
64 Holding_Buffer = Double_Overlay [0];
66 Double_Overlay [0] = htonl (Double_Overlay [1]);
67 Double_Overlay [1] = htonl (Holding_Buffer);
74 static void htonf (float &x)
76 if ( sgIsLittleEndian() ) {
80 Float_Overlay = (int *) &x;
81 Holding_Buffer = Float_Overlay [0];
83 Float_Overlay [0] = htonl (Holding_Buffer);
90 FGNativeFDM::FGNativeFDM() {
93 FGNativeFDM::~FGNativeFDM() {
97 // open hailing frequencies
98 bool FGNativeFDM::open() {
100 SG_LOG( SG_IO, SG_ALERT, "This shouldn't happen, but the channel "
101 << "is already in use, ignoring" );
105 SGIOChannel *io = get_io_channel();
107 if ( ! io->open( get_direction() ) ) {
108 SG_LOG( SG_IO, SG_ALERT, "Error opening channel communication layer." );
114 // Is this really needed here ????
115 cur_fdm_state->_set_Sea_level_radius( SG_EQUATORIAL_RADIUS_FT );
121 void FGProps2NetFDM( FGNetFDM *net, bool net_byte_order ) {
124 // Version sanity checking
125 net->version = FG_NET_FDM_VERSION;
128 net->longitude = cur_fdm_state->get_Longitude();
129 net->latitude = cur_fdm_state->get_Latitude();
130 net->altitude = cur_fdm_state->get_Altitude() * SG_FEET_TO_METER;
131 net->agl = cur_fdm_state->get_Altitude_AGL() * SG_FEET_TO_METER;
132 net->phi = cur_fdm_state->get_Phi();
133 net->theta = cur_fdm_state->get_Theta();
134 net->psi = cur_fdm_state->get_Psi();
135 net->phidot = cur_fdm_state->get_Phi_dot_degps() * SG_DEGREES_TO_RADIANS;
136 net->thetadot = cur_fdm_state->get_Theta_dot_degps()
137 * SG_DEGREES_TO_RADIANS;
138 net->psidot = cur_fdm_state->get_Psi_dot_degps() * SG_DEGREES_TO_RADIANS;
140 net->vcas = cur_fdm_state->get_V_calibrated_kts();
141 net->climb_rate = cur_fdm_state->get_Climb_Rate();
143 net->v_north = cur_fdm_state->get_V_north();
144 net->v_east = cur_fdm_state->get_V_east();
145 net->v_down = cur_fdm_state->get_V_down();
146 net->v_wind_body_north = cur_fdm_state->get_uBody();
147 net->v_wind_body_east = cur_fdm_state->get_vBody();
148 net->v_wind_body_down = cur_fdm_state->get_wBody();
149 net->stall_warning = fgGetDouble("/sim/alarms/stall-warning", 0.0);
151 net->A_X_pilot = cur_fdm_state->get_A_X_pilot();
152 net->A_Y_pilot = cur_fdm_state->get_A_Y_pilot();
153 net->A_Z_pilot = cur_fdm_state->get_A_Z_pilot();
156 net->num_engines = FGNetFDM::FG_MAX_ENGINES;
157 for ( i = 0; i < net->num_engines; ++i ) {
158 SGPropertyNode *node = fgGetNode("engines/engine", i, true);
159 if ( node->getBoolValue( "running" ) ) {
160 net->eng_state[0] = 2;
161 } else if ( node->getBoolValue( "cranking" ) ) {
162 net->eng_state[0] = 1;
164 net->eng_state[0] = 0;
166 net->rpm[i] = node->getDoubleValue( "rpm" );
167 net->fuel_flow[i] = node->getDoubleValue( "fuel-flow-gph" );
168 net->EGT[i] = node->getDoubleValue( "egt-degf" );
169 // cout << "egt = " << aero->EGT << endl;
170 net->oil_temp[i] = node->getDoubleValue( "oil-temperature-degf" );
171 net->oil_px[i] = node->getDoubleValue( "oil-pressure-psi" );
175 net->num_tanks = FGNetFDM::FG_MAX_TANKS;
176 for ( i = 0; i < net->num_tanks; ++i ) {
177 SGPropertyNode *node = fgGetNode("/consumables/fuel/tank", i, true);
178 net->fuel_quantity[i] = node->getDoubleValue("level-gal_us");
182 net->num_wheels = FGNetFDM::FG_MAX_WHEELS;
183 for (i = 0; i < net->num_wheels; ++i ) {
184 SGPropertyNode *node = fgGetNode("/gear/gear", i, true);
185 net->wow[i] = node->getDoubleValue("wow");
186 net->gear_pos[i] = node->getDoubleValue("position-norm");
187 net->gear_steer[i] = node->getDoubleValue("steering-norm");
188 net->gear_compression[i] = node->getDoubleValue("compression-norm");
191 // the following really aren't used in this context
192 net->cur_time = globals->get_time_params()->get_cur_time();
193 net->warp = globals->get_warp();
194 net->visibility = fgGetDouble("/environment/visibility-m");
196 // Control surface positions
197 SGPropertyNode *node = fgGetNode("/surface-positions", true);
198 net->elevator = node->getDoubleValue( "elevator-pos-norm" );
199 net->flaps = node->getDoubleValue( "flap-pos-norm" );
200 net->left_aileron = node->getDoubleValue( "left-aileron-pos-norm" );
201 net->right_aileron = node->getDoubleValue( "right-aileron-pos-norm" );
202 net->rudder = node->getDoubleValue( "rudder-pos-norm" );
203 net->speedbrake = node->getDoubleValue( "speedbrake-pos-norm" );
204 net->spoilers = node->getDoubleValue( "spoilers-pos-norm" );
206 if ( net_byte_order ) {
207 // Convert the net buffer to network format
208 net->version = htonl(net->version);
210 htond(net->longitude);
211 htond(net->latitude);
212 htond(net->altitude);
219 htonf(net->thetadot);
222 htonf(net->climb_rate);
226 htonf(net->v_wind_body_north);
227 htonf(net->v_wind_body_east);
228 htonf(net->v_wind_body_down);
229 htonf(net->stall_warning);
231 htonf(net->A_X_pilot);
232 htonf(net->A_Y_pilot);
233 htonf(net->A_Z_pilot);
235 for ( i = 0; i < net->num_engines; ++i ) {
236 htonl(net->eng_state[i]);
238 htonf(net->fuel_flow[i]);
240 htonf(net->oil_temp[i]);
241 htonf(net->oil_px[i]);
243 net->num_engines = htonl(net->num_engines);
245 for ( i = 0; i < net->num_tanks; ++i ) {
246 htonf(net->fuel_quantity[i]);
248 net->num_tanks = htonl(net->num_tanks);
250 for ( i = 0; i < net->num_wheels; ++i ) {
252 htonf(net->gear_pos[i]);
253 htonf(net->gear_steer[i]);
254 htonf(net->gear_compression[i]);
256 net->num_wheels = htonl(net->num_wheels);
258 net->cur_time = htonl( net->cur_time );
259 net->warp = htonl( net->warp );
260 htonf(net->visibility);
262 htonf(net->elevator);
264 htonf(net->left_aileron);
265 htonf(net->right_aileron);
267 htonf(net->speedbrake);
268 htonf(net->spoilers);
273 void FGNetFDM2Props( FGNetFDM *net, bool net_byte_order ) {
276 if ( net_byte_order ) {
277 // Convert to the net buffer from network format
278 net->version = ntohl(net->version);
280 htond(net->longitude);
281 htond(net->latitude);
282 htond(net->altitude);
289 htonf(net->thetadot);
292 htonf(net->climb_rate);
296 htonf(net->v_wind_body_north);
297 htonf(net->v_wind_body_east);
298 htonf(net->v_wind_body_down);
299 htonf(net->stall_warning);
301 htonf(net->A_X_pilot);
302 htonf(net->A_Y_pilot);
303 htonf(net->A_Z_pilot);
305 net->num_engines = htonl(net->num_engines);
306 for ( i = 0; i < net->num_engines; ++i ) {
307 htonl(net->eng_state[i]);
309 htonf(net->fuel_flow[i]);
311 htonf(net->oil_temp[i]);
312 htonf(net->oil_px[i]);
315 net->num_tanks = htonl(net->num_tanks);
316 for ( i = 0; i < net->num_tanks; ++i ) {
317 htonf(net->fuel_quantity[i]);
320 net->num_wheels = htonl(net->num_wheels);
321 for ( i = 0; i < net->num_wheels; ++i ) {
323 htonf(net->gear_pos[i]);
324 htonf(net->gear_steer[i]);
325 htonf(net->gear_compression[i]);
328 net->cur_time = ntohl(net->cur_time);
329 net->warp = ntohl(net->warp);
330 htonf(net->visibility);
332 htonf(net->elevator);
334 htonf(net->left_aileron);
335 htonf(net->right_aileron);
337 htonf(net->speedbrake);
338 htonf(net->spoilers);
341 if ( net->version == FG_NET_FDM_VERSION ) {
342 // cout << "pos = " << net->longitude << " " << net->latitude << endl;
343 // cout << "sea level rad = " << cur_fdm_state->get_Sea_level_radius()
345 cur_fdm_state->_updateGeodeticPosition( net->latitude,
348 * SG_METER_TO_FEET );
349 cur_fdm_state->_set_Altitude_AGL( net->agl * SG_METER_TO_FEET );
350 cur_fdm_state->_set_Euler_Angles( net->phi,
353 cur_fdm_state->_set_Euler_Rates( net->phidot,
356 cur_fdm_state->_set_V_calibrated_kts( net->vcas );
357 cur_fdm_state->_set_Climb_Rate( net->climb_rate );
358 cur_fdm_state->_set_Velocities_Local( net->v_north,
361 cur_fdm_state->_set_Velocities_Wind_Body( net->v_wind_body_north,
362 net->v_wind_body_east,
363 net->v_wind_body_down );
365 fgSetDouble( "/sim/alarms/stall-warning", net->stall_warning );
366 cur_fdm_state->_set_Accels_Pilot_Body( net->A_X_pilot,
370 for ( i = 0; i < net->num_engines; ++i ) {
371 SGPropertyNode *node = fgGetNode( "engines/engine", i, true );
373 // node->setBoolValue("running", t->isRunning());
374 // node->setBoolValue("cranking", t->isCranking());
376 // cout << net->eng_state[i] << endl;
377 if ( net->eng_state[i] == 0 ) {
378 node->setBoolValue( "cranking", false );
379 node->setBoolValue( "running", false );
380 } else if ( net->eng_state[i] == 1 ) {
381 node->setBoolValue( "cranking", true );
382 node->setBoolValue( "running", false );
383 } else if ( net->eng_state[i] == 2 ) {
384 node->setBoolValue( "cranking", false );
385 node->setBoolValue( "running", true );
388 node->setDoubleValue( "rpm", net->rpm[i] );
389 node->setDoubleValue( "fuel-flow-gph", net->fuel_flow[i] );
390 node->setDoubleValue( "egt-degf", net->EGT[i] );
391 node->setDoubleValue( "oil-temperature-degf", net->oil_temp[i] );
392 node->setDoubleValue( "oil-pressure-psi", net->oil_px[i] );
395 for (i = 0; i < net->num_tanks; ++i ) {
396 SGPropertyNode * node
397 = fgGetNode("/consumables/fuel/tank", i, true);
398 node->setDoubleValue("level-gal_us", net->fuel_quantity[i] );
401 for (i = 0; i < net->num_wheels; ++i ) {
402 SGPropertyNode * node = fgGetNode("/gear/gear", i, true);
403 node->setDoubleValue("wow", net->wow[i] );
404 node->setDoubleValue("position-norm", net->gear_pos[i] );
405 node->setDoubleValue("steering-norm", net->gear_steer[i] );
406 node->setDoubleValue("compression-norm", net->gear_compression[i] );
409 /* these are ignored for now ... */
411 if ( net->cur_time ) {
412 fgSetLong("/sim/time/cur-time-override", net->cur_time);
415 globals->set_warp( net->warp );
416 last_warp = net->warp;
419 SGPropertyNode *node = fgGetNode("/surface-positions", true);
420 node->setDoubleValue("elevator-pos-norm", net->elevator);
421 node->setDoubleValue("flap-pos-norm", net->flaps);
422 node->setDoubleValue("left-aileron-pos-norm", net->left_aileron);
423 node->setDoubleValue("right-aileron-pos-norm", net->right_aileron);
424 node->setDoubleValue("rudder-pos-norm", net->rudder);
425 node->setDoubleValue("speedbrake-pos-norm", net->speedbrake);
426 node->setDoubleValue("spoilers-pos-norm", net->spoilers);
428 SG_LOG( SG_IO, SG_ALERT,
429 "Error: version mismatch in FGNetFDM2Props()" );
430 SG_LOG( SG_IO, SG_ALERT,
431 "\tread " << net->version << " need " << FG_NET_FDM_VERSION );
432 SG_LOG( SG_IO, SG_ALERT,
433 "\tNeeds to upgrade net_fdm.hxx and recompile." );
438 // process work for this port
439 bool FGNativeFDM::process() {
440 SGIOChannel *io = get_io_channel();
441 int length = sizeof(buf);
443 if ( get_direction() == SG_IO_OUT ) {
444 // cout << "size of cur_fdm_state = " << length << endl;
445 FGProps2NetFDM( &buf );
446 if ( ! io->write( (char *)(& buf), length ) ) {
447 SG_LOG( SG_IO, SG_ALERT, "Error writing data." );
450 } else if ( get_direction() == SG_IO_IN ) {
451 if ( io->get_type() == sgFileType ) {
452 if ( io->read( (char *)(& buf), length ) == length ) {
453 SG_LOG( SG_IO, SG_DEBUG, "Success reading data." );
454 FGNetFDM2Props( &buf );
458 result = io->read( (char *)(& buf), length );
459 while ( result == length ) {
460 if ( result == length ) {
461 SG_LOG( SG_IO, SG_DEBUG, " Success reading data." );
462 FGNetFDM2Props( &buf );
464 result = io->read( (char *)(& buf), length );
474 bool FGNativeFDM::close() {
475 SGIOChannel *io = get_io_channel();
477 set_enabled( false );
479 if ( ! io->close() ) {