1 // flight.hxx -- define shared flight model parameters
2 //
3 // Written by Curtis Olson, started May 1997.
4 //
5 // Copyright (C) 1997  Curtis L. Olson  - http://www.flightgear.org/~curt
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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
20 //
21 // $Id$
22 
23 
24 #ifndef _FLIGHT_HXX
25 #define _FLIGHT_HXX
26 
27 
28 #ifndef __cplusplus
29 # error This library requires C++
30 #endif
31 
32 
33 /* Required get_()
34 
35    `FGInterface::get_Longitude ()'
36    `FGInterface::get_Latitude ()'
37    `FGInterface::get_Altitude ()'
38    `FGInterface::get_Phi ()'
39    `FGInterface::get_Theta ()'
40    `FGInterface::get_Psi ()'
41    `FGInterface::get_V_equiv_kts ()'
42 
43    `FGInterface::get_V_north ()'
44    `FGInterface::get_V_east ()'
45    `FGInterface::get_V_down ()'
46 
47    `FGInterface::get_P_Body ()'
48    `FGInterface::get_Q_Body ()'
49    `FGInterface::get_R_Body ()'
50 
51    `FGInterface::get_Gamma_vert_rad ()'
52    `FGInterface::get_Climb_Rate ()'
53    `FGInterface::get_Alpha ()'
54    `FGInterface::get_Beta ()'
55 
56    `FGInterface::get_Runway_altitude ()'
57 
58    `FGInterface::get_Lon_geocentric ()'
59    `FGInterface::get_Lat_geocentric ()'
60    `FGInterface::get_Sea_level_radius ()'
61    `FGInterface::get_Earth_position_angle ()'
62 
63    `FGInterface::get_Latitude_dot()'
64    `FGInterface::get_Longitude_dot()'
65    `FGInterface::get_Radius_dot()'
66 
67    `FGInterface::get_Dx_cg ()'
68    `FGInterface::get_Dy_cg ()'
69    `FGInterface::get_Dz_cg ()'
70 
71    `FGInterface::get_Radius_to_vehicle ()'
72 
73  */
74 
75 
76 #include <cmath>
77 
78 #include <simgear/compiler.h>
79 #include <simgear/constants.h>
80 #include <simgear/structure/subsystem_mgr.hxx>
81 #include <simgear/props/tiedpropertylist.hxx>
82 #include <FDM/groundcache.hxx>
83 #include <FDM/AIWake/AIWakeGroup.hxx>
84 
85 namespace simgear {
86 class BVHMaterial;
87 }
88 
89 class SGIOChannel;
90 class FGAIAircraft;
91 
92 /**
93  * A little helper class to update the track if
94  * the position has changed. In the constructor,
95  * create a copy of the current position and store
96  * references to the position object and the track
97  * variable to update.
98  * The destructor, called at TrackComputer's end of
99  * life/visibility, computes the track if the
100  * position has changed.
101  */
102 class TrackComputer
103 {
104 public:
TrackComputer(double & track,double & path,const SGGeod & position)105     inline TrackComputer( double & track, double & path, const SGGeod & position ) :
106         _track( track ),
107         _path( path ),
108         _position( position ),
109         _prevPosition( position ) {
110     }
111 
~TrackComputer()112     inline ~TrackComputer() {
113         if( _prevPosition == _position ) return;
114 //        _track = SGGeodesy::courseDeg( _prevPosition, _position );
115         double d = .0;
116         double distance = .0;
117         if( SGGeodesy::inverse( _prevPosition, _position, _track, d, distance ) ) {
118             d = _position.getElevationM() - _prevPosition.getElevationM();
119             _path = atan2( d, distance ) * SGD_RADIANS_TO_DEGREES;
120         }
121     }
122 
123 private:
124     double & _track;
125     double & _path;
126     const SGGeod & _position;
127     const SGGeod _prevPosition;
128 };
129 
130 // This is based heavily on LaRCsim/ls_generic.h
131 class FGInterface : public SGSubsystem
132 {
133     // Has the init() method been called.  This is used to delay
134     // initialization until scenery can be loaded and we know the true
135     // ground elevation.
136     bool inited;
137 
138     // Have we bound to the property system
139     bool bound;
140 
141     // periodic update management variable.  This is a scheme to run
142     // the fdm with a fixed delta-t.  We control how many iteration of
143     // the fdm to run with the fixed dt based on the elapsed time from
144     // the last update.  This allows us to maintain sync with the real
145     // time clock, even though each frame could take a random amount
146     // of time.  Since "dt" is unlikely to divide evenly into the
147     // elapse time, we keep track of the remainder and add it into the
148     // next elapsed time.  This yields a small amount of temporal
149     // jitter ( < dt ) but in practice seems to work well.
150 
151     /**
152      * encapsulate primary flight state. This is packaged so it can be
153      * (unfortunately) sent directly over the wire by the 'native' FDM
154      * protocol.
155      */
156     struct FlightState
157     {
158         // CG position w.r.t. ref. point
159         SGVec3d d_cg_rp_body_v;
160 
161         // Accelerations
162         SGVec3d v_dot_local_v;
163         SGVec3d v_dot_body_v;
164         SGVec3d a_cg_body_v;
165         SGVec3d a_pilot_body_v;
166         SGVec3d n_cg_body_v;
167         SGVec3d omega_dot_body_v;
168 
169         // Velocities
170         SGVec3d v_local_v;
171         SGVec3d v_local_rel_ground_v; // V rel w.r.t. earth surface
172         SGVec3d v_local_airmass_v;    // velocity of airmass (steady winds)
173         SGVec3d v_body_v;        // ECEF velocities in body axis
174 
175         SGVec3d omega_body_v;         // Angular B rates
176         SGVec3d euler_rates_v;
177         SGVec3d geocentric_rates_v;   // Geocentric linear velocities
178 
179         // Positions
180         SGGeod geodetic_position_v;
181         SGVec3d cartesian_position_v;
182         SGGeoc geocentric_position_v;
183         SGVec3d euler_angles_v;
184 
185         // Normal Load Factor
186         double nlf;
187 
188         // Velocities
189         double v_rel_wind, v_true_kts;
190         double v_ground_speed, v_equiv_kts;
191         double v_calibrated_kts;
192 
193         // Miscellaneious Quantities
194         double alpha, beta;  // in radians
195         double gamma_vert_rad;  // Flight path angles
196         double density, mach_number;
197         double static_pressure, total_pressure;
198         double dynamic_pressure;
199         double static_temperature, total_temperature;
200         double sea_level_radius, earth_position_angle;
201         double runway_altitude;
202         double climb_rate;                // in feet per second
203         double altitude_agl;
204         double track;
205         double path;
206     };
207 
208     FlightState _state;
209 
210     simgear::TiedPropertyList _tiedProperties;
211 
212     // the ground cache object itself.
213     FGGroundCache ground_cache;
214 
215     AIWakeGroup wake_group;
216 
set_A_X_pilot(double x)217     void set_A_X_pilot(double x)
218     { _set_Accels_Pilot_Body(x, _state.a_pilot_body_v[1], _state.a_pilot_body_v[2]); }
219 
set_A_Y_pilot(double y)220     void set_A_Y_pilot(double y)
221     { _set_Accels_Pilot_Body(_state.a_pilot_body_v[0], y, _state.a_pilot_body_v[2]); }
222 
set_A_Z_pilot(double z)223     void set_A_Z_pilot(double z)
224     { _set_Accels_Pilot_Body(_state.a_pilot_body_v[0], _state.a_pilot_body_v[1], z); }
225 
226 protected:
227     int _calc_multiloop (double dt);
228 
229 
230     // deliberately not virtual so that
231     // FGInterface constructor will call
232     // the right version
233     void _setup();
234 
235     void _busdump(void);
236     void _updatePositionM(const SGVec3d& cartPos);
_updatePositionFt(const SGVec3d & cartPos)237     void _updatePositionFt(const SGVec3d& cartPos) {
238         _updatePositionM(SG_FEET_TO_METER*cartPos);
239     }
240     void _updatePosition(const SGGeod& geod);
241     void _updatePosition(const SGGeoc& geoc);
242 
243     void _updateGeodeticPosition( double lat, double lon, double alt );
244     void _updateGeocentricPosition( double lat_geoc, double lon, double alt );
245     void _update_ground_elev_at_pos( void );
246 
_set_CG_Position(double dx,double dy,double dz)247     inline void _set_CG_Position( double dx, double dy, double dz ) {
248         _state.d_cg_rp_body_v[0] = dx;
249         _state.d_cg_rp_body_v[1] = dy;
250         _state.d_cg_rp_body_v[2] = dz;
251     }
_set_Accels_Local(double north,double east,double down)252     inline void _set_Accels_Local( double north, double east, double down ) {
253         _state.v_dot_local_v[0] = north;
254         _state.v_dot_local_v[1] = east;
255         _state.v_dot_local_v[2] = down;
256     }
_set_Accels_Body(double u,double v,double w)257     inline void _set_Accels_Body( double u, double v, double w ) {
258         _state.v_dot_body_v[0] = u;
259         _state.v_dot_body_v[1] = v;
260         _state.v_dot_body_v[2] = w;
261     }
_set_Accels_CG_Body(double x,double y,double z)262     inline void _set_Accels_CG_Body( double x, double y, double z ) {
263         _state.a_cg_body_v[0] = x;
264         _state.a_cg_body_v[1] = y;
265         _state.a_cg_body_v[2] = z;
266     }
_set_Accels_Pilot_Body(double x,double y,double z)267     inline void _set_Accels_Pilot_Body( double x, double y, double z ) {
268         _state.a_pilot_body_v[0] = x;
269         _state.a_pilot_body_v[1] = y;
270         _state.a_pilot_body_v[2] = z;
271     }
_set_Accels_CG_Body_N(double x,double y,double z)272     inline void _set_Accels_CG_Body_N( double x, double y, double z ) {
273         _state.n_cg_body_v[0] = x;
274         _state.n_cg_body_v[1] = y;
275         _state.n_cg_body_v[2] = z;
276     }
_set_Nlf(double n)277     void _set_Nlf(double n) { _state.nlf=n;  }
_set_Velocities_Local(double north,double east,double down)278     inline void _set_Velocities_Local( double north, double east, double down ){
279         _state.v_local_v[0] = north;
280         _state.v_local_v[1] = east;
281         _state.v_local_v[2] = down;
282     }
_set_Velocities_Ground(double north,double east,double down)283     inline void _set_Velocities_Ground(double north, double east, double down) {
284         _state.v_local_rel_ground_v[0] = north;
285         _state.v_local_rel_ground_v[1] = east;
286         _state.v_local_rel_ground_v[2] = down;
287     }
_set_Velocities_Local_Airmass(double north,double east,double down)288     inline void _set_Velocities_Local_Airmass( double north, double east,
289                                               double down)
290     {
291         _state.v_local_airmass_v[0] = north;
292         _state.v_local_airmass_v[1] = east;
293         _state.v_local_airmass_v[2] = down;
294     }
_set_Velocities_Body(double u,double v,double w)295     inline void _set_Velocities_Body( double u, double v, double w) {
296         _state.v_body_v[0] = u;
297         _state.v_body_v[1] = v;
298         _state.v_body_v[2] = w;
299     }
_set_V_rel_wind(double vt)300     inline void _set_V_rel_wind(double vt) { _state.v_rel_wind = vt; }
_set_V_ground_speed(double v)301     inline void _set_V_ground_speed( double v) { _state.v_ground_speed = v; }
_set_V_equiv_kts(double kts)302     inline void _set_V_equiv_kts( double kts ) { _state.v_equiv_kts = kts; }
_set_V_calibrated_kts(double kts)303     inline void _set_V_calibrated_kts( double kts ) { _state.v_calibrated_kts = kts; }
_set_Omega_Body(double p,double q,double r)304     inline void _set_Omega_Body( double p, double q, double r ) {
305         _state.omega_body_v[0] = p;
306         _state.omega_body_v[1] = q;
307         _state.omega_body_v[2] = r;
308     }
_set_Euler_Rates(double phi,double theta,double psi)309     inline void _set_Euler_Rates( double phi, double theta, double psi ) {
310         _state.euler_rates_v[0] = phi;
311         _state.euler_rates_v[1] = theta;
312         _state.euler_rates_v[2] = psi;
313     }
314 
set_Phi_dot_degps(double x)315     void set_Phi_dot_degps(double x)
316     {
317         _state.euler_rates_v[0] = x * SGD_DEGREES_TO_RADIANS;
318     }
319 
set_Theta_dot_degps(double x)320     void set_Theta_dot_degps(double x)
321     {
322         _state.euler_rates_v[1] = x * SGD_DEGREES_TO_RADIANS;
323     }
324 
set_Psi_dot_degps(double x)325     void set_Psi_dot_degps(double x)
326     {
327         _state.euler_rates_v[2] = x * SGD_DEGREES_TO_RADIANS;
328     }
329 
_set_Geocentric_Rates(double lat,double lon,double rad)330     inline void _set_Geocentric_Rates( double lat, double lon, double rad ) {
331         _state.geocentric_rates_v[0] = lat;
332         _state.geocentric_rates_v[1] = lon;
333         _state.geocentric_rates_v[2] = rad;
334     }
_set_Geocentric_Position(double lat,double lon,double rad)335     inline void _set_Geocentric_Position( double lat, double lon, double rad ) {
336         _state.geocentric_position_v.setLatitudeRad(lat);
337         _state.geocentric_position_v.setLongitudeRad(lon);
338         _state.geocentric_position_v.setRadiusFt(rad);
339     }
340 /*  Don't call _set_L[at|ong]itude() directly, use _set_Geodetic_Position() instead.
341     These methods can't update the track.
342  *
343     inline void _set_Latitude(double lat) {
344         geodetic_position_v.setLatitudeRad(lat);
345     }
346     inline void _set_Longitude(double lon) {
347         geodetic_position_v.setLongitudeRad(lon);
348     }
349 */
_set_Altitude(double altitude)350     inline void _set_Altitude(double altitude) {
351         _state.geodetic_position_v.setElevationFt(altitude);
352     }
_set_Altitude_AGL(double agl)353     inline void _set_Altitude_AGL(double agl) {
354         _state.altitude_agl = agl;
355     }
_set_Geodetic_Position(double lat,double lon)356     inline void _set_Geodetic_Position( double lat, double lon ) {
357         _set_Geodetic_Position( lat, lon, _state.geodetic_position_v.getElevationFt());
358     }
_set_Geodetic_Position(double lat,double lon,double alt)359     inline void _set_Geodetic_Position( double lat, double lon, double alt ) {
360         TrackComputer tracker( _state.track, _state.path, _state.geodetic_position_v );
361         _state.geodetic_position_v.setLatitudeRad(lat);
362         _state.geodetic_position_v.setLongitudeRad(lon);
363         _state.geodetic_position_v.setElevationFt(alt);
364     }
_set_Euler_Angles(double phi,double theta,double psi)365     inline void _set_Euler_Angles( double phi, double theta, double psi ) {
366         _state.euler_angles_v[0] = phi;
367         _state.euler_angles_v[1] = theta;
368         _state.euler_angles_v[2] = psi;
369     }
370     // FIXME, for compatibility with JSBSim
_set_T_Local_to_Body(int i,int j,double value)371     inline void _set_T_Local_to_Body( int i, int j, double value) { }
_set_Alpha(double a)372     inline void _set_Alpha( double a ) { _state.alpha = a; }
_set_Beta(double b)373     inline void _set_Beta( double b ) { _state.beta = b; }
374 
set_Alpha_deg(double a)375     inline void set_Alpha_deg( double a ) { _state.alpha = a * SGD_DEGREES_TO_RADIANS; }
376 
_set_Gamma_vert_rad(double gv)377     inline void _set_Gamma_vert_rad( double gv ) { _state.gamma_vert_rad = gv; }
_set_Density(double d)378     inline void _set_Density( double d ) { _state.density = d; }
_set_Mach_number(double m)379     inline void _set_Mach_number( double m ) { _state.mach_number = m; }
_set_Static_pressure(double sp)380     inline void _set_Static_pressure( double sp ) { _state.static_pressure = sp; }
_set_Static_temperature(double t)381     inline void _set_Static_temperature( double t ) { _state.static_temperature = t; }
_set_Total_temperature(double tat)382     inline void _set_Total_temperature( double tat ) { _state.total_temperature = tat; } //JW
_set_Sea_level_radius(double r)383     inline void _set_Sea_level_radius( double r ) { _state.sea_level_radius = r; }
_set_Earth_position_angle(double a)384     inline void _set_Earth_position_angle(double a) {_state.earth_position_angle = a; }
_set_Runway_altitude(double alt)385     inline void _set_Runway_altitude( double alt ) { _state.runway_altitude = alt; }
_set_Climb_Rate(double rate)386     inline void _set_Climb_Rate(double rate) { _state.climb_rate = rate; }
387 
388 public:
389     FGInterface();
390     FGInterface( double dt );
391     virtual ~FGInterface();
392 
393     // Subsystem API.
394     void bind() override;
395     void init() override;
396     void unbind() override;
397     void update(double dt) override;
398 
ToggleDataLogging(bool state)399     virtual bool ToggleDataLogging(bool state) { return false; }
ToggleDataLogging(void)400     virtual bool ToggleDataLogging(void) { return false; }
401 
402     bool readState(SGIOChannel* io);
403     bool writeState(SGIOChannel* io);
404 
405     // Define the various supported flight models (many not yet implemented)
406     enum {
407         // Magic Carpet mode
408         FG_MAGICCARPET = 0,
409 
410         // The NASA LaRCsim (Navion) flight model
411         FG_LARCSIM = 1,
412 
413         // Jon S. Berndt's new FDM written from the ground up in C++
414         FG_JSBSIM = 2,
415 
416         // Christian's hot air balloon simulation
417         FG_BALLOONSIM = 3,
418 
419         // Aeronautical DEvelopment AGEncy, Bangalore India
420         FG_ADA = 4,
421 
422         // The following aren't implemented but are here to spark
423         // thoughts and discussions, and maybe even action.
424         FG_ACM = 5,
425         FG_SUPER_SONIC = 6,
426         FG_HELICOPTER = 7,
427         FG_AUTOGYRO = 8,
428         FG_PARACHUTE = 9,
429 
430         // Driven externally via a serial port, net, file, etc.
431         FG_EXTERNAL = 10
432     };
433 
434     // initialization
get_inited() const435     inline bool get_inited() const { return inited; }
set_inited(bool value)436     inline void set_inited( bool value ) { inited = value; }
437 
get_bound() const438     inline bool get_bound() const { return bound; }
439 
440     //perform initializion that is common to all FDM's
441     void common_init();
442 
443     // Positions
444     virtual void set_Latitude(double lat);       // geocentric
445     virtual void set_Longitude(double lon);
446     virtual void set_Altitude(double alt);  // triggers re-calc of AGL altitude
447     virtual void set_AltitudeAGL(double altagl); // and vice-versa
set_Latitude_deg(double lat)448     virtual void set_Latitude_deg (double lat) {
449         set_Latitude(lat * SGD_DEGREES_TO_RADIANS);
450     }
set_Longitude_deg(double lon)451     virtual void set_Longitude_deg (double lon) {
452         set_Longitude(lon * SGD_DEGREES_TO_RADIANS);
453     }
454 
455     // Speeds -- setting any of these will trigger a re-calc of the rest
456     virtual void set_V_calibrated_kts(double vc);
457     virtual void set_Mach_number(double mach);
458     virtual void set_Velocities_Local( double north, double east, double down );
set_V_north(double north)459     inline void set_V_north (double north) {
460         set_Velocities_Local(north, _state.v_local_v[1], _state.v_local_v[2]);
461     }
set_V_east(double east)462     inline void set_V_east (double east) {
463         set_Velocities_Local(_state.v_local_v[0], east, _state.v_local_v[2]);
464     }
set_V_down(double down)465     inline void set_V_down (double down) {
466         set_Velocities_Local(_state.v_local_v[0], _state.v_local_v[1], down);
467     }
468     virtual void set_Velocities_Body( double u, double v, double w);
set_uBody(double uBody)469     virtual void set_uBody (double uBody) {
470         set_Velocities_Body(uBody, _state.v_body_v[1], _state.v_body_v[2]);
471     }
set_vBody(double vBody)472     virtual void set_vBody (double vBody) {
473         set_Velocities_Body(_state.v_body_v[0], vBody, _state.v_body_v[2]);
474     }
set_wBody(double wBody)475     virtual void set_wBody (double wBody) {
476         set_Velocities_Body(_state.v_body_v[0], _state.v_body_v[1], wBody);
477     }
478 
479     // Euler angles
480     virtual void set_Euler_Angles( double phi, double theta, double psi );
set_Phi(double phi)481     virtual void set_Phi (double phi) {
482         set_Euler_Angles(phi, get_Theta(), get_Psi());
483     }
set_Theta(double theta)484     virtual void set_Theta (double theta) {
485         set_Euler_Angles(get_Phi(), theta, get_Psi());
486     }
set_Psi(double psi)487     virtual void set_Psi (double psi) {
488         set_Euler_Angles(get_Phi(), get_Theta(), psi);
489     }
set_Phi_deg(double phi)490     virtual void set_Phi_deg (double phi) {
491         set_Phi(phi * SGD_DEGREES_TO_RADIANS);
492     }
set_Theta_deg(double theta)493     virtual void set_Theta_deg (double theta) {
494         set_Theta(theta * SGD_DEGREES_TO_RADIANS);
495     }
set_Psi_deg(double psi)496     virtual void set_Psi_deg (double psi) {
497         set_Psi(psi * SGD_DEGREES_TO_RADIANS);
498     }
499 
500     // Flight Path
501     virtual void set_Climb_Rate( double roc);
502     virtual void set_Gamma_vert_rad( double gamma);
503 
504     // Earth
505 
506     virtual void set_Static_pressure(double p);
507     virtual void set_Static_temperature(double T);
508     virtual void set_Density(double rho);
509 
510     virtual void set_Velocities_Local_Airmass (double wnorth,
511                                                double weast,
512                                                double wdown );
513 
514     // ========== Mass properties and geometry values ==========
515 
516     // CG position w.r.t. ref. point
get_Dx_cg() const517     inline double get_Dx_cg() const { return _state.d_cg_rp_body_v[0]; }
get_Dy_cg() const518     inline double get_Dy_cg() const { return _state.d_cg_rp_body_v[1]; }
get_Dz_cg() const519     inline double get_Dz_cg() const { return _state.d_cg_rp_body_v[2]; }
520 
521     // ========== Accelerations ==========
522 
get_V_dot_north() const523     inline double get_V_dot_north() const { return _state.v_dot_local_v[0]; }
get_V_dot_east() const524     inline double get_V_dot_east() const { return _state.v_dot_local_v[1]; }
get_V_dot_down() const525     inline double get_V_dot_down() const { return _state.v_dot_local_v[2]; }
526 
get_U_dot_body() const527     inline double get_U_dot_body() const { return _state.v_dot_body_v[0]; }
get_V_dot_body() const528     inline double get_V_dot_body() const { return _state.v_dot_body_v[1]; }
get_W_dot_body() const529     inline double get_W_dot_body() const { return _state.v_dot_body_v[2]; }
530 
get_A_X_cg() const531     inline double get_A_X_cg() const { return _state.a_cg_body_v[0]; }
get_A_Y_cg() const532     inline double get_A_Y_cg() const { return _state.a_cg_body_v[1]; }
get_A_Z_cg() const533     inline double get_A_Z_cg() const { return _state.a_cg_body_v[2]; }
534 
get_A_X_pilot() const535     inline double get_A_X_pilot() const { return _state.a_pilot_body_v[0]; }
get_A_Y_pilot() const536     inline double get_A_Y_pilot() const { return _state.a_pilot_body_v[1]; }
get_A_Z_pilot() const537     inline double get_A_Z_pilot() const { return _state.a_pilot_body_v[2]; }
538 
get_N_X_cg() const539     inline double get_N_X_cg() const { return _state.n_cg_body_v[0]; }
get_N_Y_cg() const540     inline double get_N_Y_cg() const { return _state.n_cg_body_v[1]; }
get_N_Z_cg() const541     inline double get_N_Z_cg() const { return _state.n_cg_body_v[2]; }
542 
get_Nlf(void) const543     inline double get_Nlf(void) const { return _state.nlf; }
544 
545     // ========== Velocities ==========
546 
get_V_north() const547     inline double get_V_north() const { return _state.v_local_v[0]; }
get_V_east() const548     inline double get_V_east() const { return _state.v_local_v[1]; }
get_V_down() const549     inline double get_V_down() const { return _state.v_local_v[2]; }
get_uBody() const550     inline double get_uBody () const { return _state.v_body_v[0]; }
get_vBody() const551     inline double get_vBody () const { return _state.v_body_v[1]; }
get_wBody() const552     inline double get_wBody () const { return _state.v_body_v[2]; }
553 
554     // Please dont comment these out. fdm=ada uses these (see
555     // cockpit.cxx) --->
get_V_north_rel_ground() const556     inline double get_V_north_rel_ground() const {
557         return _state.v_local_rel_ground_v[0];
558     }
get_V_east_rel_ground() const559     inline double get_V_east_rel_ground() const {
560         return _state.v_local_rel_ground_v[1];
561     }
get_V_down_rel_ground() const562     inline double get_V_down_rel_ground() const {
563         return _state.v_local_rel_ground_v[2];
564     }
565     // <--- fdm=ada uses these (see cockpit.cxx)
566 
get_V_north_airmass() const567     inline double get_V_north_airmass() const { return _state.v_local_airmass_v[0]; }
get_V_east_airmass() const568     inline double get_V_east_airmass() const { return _state.v_local_airmass_v[1]; }
get_V_down_airmass() const569     inline double get_V_down_airmass() const { return _state.v_local_airmass_v[2]; }
570 
get_U_body() const571     inline double get_U_body() const { return _state.v_body_v[0]; }
get_V_body() const572     inline double get_V_body() const { return _state.v_body_v[1]; }
get_W_body() const573     inline double get_W_body() const { return _state.v_body_v[2]; }
574 
get_V_rel_wind() const575     inline double get_V_rel_wind() const { return _state.v_rel_wind; }
576 
get_V_true_kts() const577     inline double get_V_true_kts() const { return _state.v_true_kts; }
578 
get_V_ground_speed() const579     inline double get_V_ground_speed() const { return _state.v_ground_speed; }
get_V_ground_speed_kt() const580     inline double get_V_ground_speed_kt() const { return _state.v_ground_speed * SG_FEET_TO_METER * 3600 * SG_METER_TO_NM; }
set_V_ground_speed_kt(double ground_speed)581     inline void   set_V_ground_speed_kt(double ground_speed) { _state.v_ground_speed = ground_speed / ( SG_FEET_TO_METER * 3600 * SG_METER_TO_NM); }
582 
get_V_equiv_kts() const583     inline double get_V_equiv_kts() const { return _state.v_equiv_kts; }
584 
get_V_calibrated_kts() const585     inline double get_V_calibrated_kts() const { return _state.v_calibrated_kts; }
586 
get_P_body() const587     inline double get_P_body() const { return _state.omega_body_v[0]; }
get_Q_body() const588     inline double get_Q_body() const { return _state.omega_body_v[1]; }
get_R_body() const589     inline double get_R_body() const { return _state.omega_body_v[2]; }
590 
get_Phi_dot() const591     inline double get_Phi_dot() const { return _state.euler_rates_v[0]; }
get_Theta_dot() const592     inline double get_Theta_dot() const { return _state.euler_rates_v[1]; }
get_Psi_dot() const593     inline double get_Psi_dot() const { return _state.euler_rates_v[2]; }
get_Phi_dot_degps() const594     inline double get_Phi_dot_degps() const { return _state.euler_rates_v[0] * SGD_RADIANS_TO_DEGREES; }
get_Theta_dot_degps() const595     inline double get_Theta_dot_degps() const { return _state.euler_rates_v[1] * SGD_RADIANS_TO_DEGREES; }
get_Psi_dot_degps() const596     inline double get_Psi_dot_degps() const { return _state.euler_rates_v[2] * SGD_RADIANS_TO_DEGREES; }
597 
get_Latitude_dot() const598     inline double get_Latitude_dot() const { return _state.geocentric_rates_v[0]; }
get_Longitude_dot() const599     inline double get_Longitude_dot() const { return _state.geocentric_rates_v[1]; }
get_Radius_dot() const600     inline double get_Radius_dot() const { return _state.geocentric_rates_v[2]; }
601 
602     // ========== Positions ==========
603 
get_Lat_geocentric() const604     inline double get_Lat_geocentric() const {
605         return _state.geocentric_position_v.getLatitudeRad();
606     }
get_Lon_geocentric() const607     inline double get_Lon_geocentric() const {
608         return _state.geocentric_position_v.getLongitudeRad();
609     }
get_Radius_to_vehicle() const610     inline double get_Radius_to_vehicle() const {
611         return _state.geocentric_position_v.getRadiusFt();
612     }
613 
getPosition() const614     const SGGeod& getPosition() const { return _state.geodetic_position_v; }
getGeocPosition() const615     const SGGeoc& getGeocPosition() const { return _state.geocentric_position_v; }
getCartPosition() const616     const SGVec3d& getCartPosition() const { return _state.cartesian_position_v; }
617 
get_Latitude() const618     inline double get_Latitude() const {
619         return _state.geodetic_position_v.getLatitudeRad();
620     }
get_Longitude() const621     inline double get_Longitude() const {
622         return _state.geodetic_position_v.getLongitudeRad();
623     }
get_Altitude() const624     inline double get_Altitude() const {
625         return _state.geodetic_position_v.getElevationFt();
626     }
get_Altitude_AGL(void) const627     inline double get_Altitude_AGL(void) const { return _state.altitude_agl; }
get_Track(void) const628     inline double get_Track(void) const { return _state.track; }
get_Path(void) const629     inline double get_Path(void) const { return _state.path; }
630 
get_Latitude_deg() const631     inline double get_Latitude_deg () const {
632       return _state.geodetic_position_v.getLatitudeDeg();
633     }
get_Longitude_deg() const634     inline double get_Longitude_deg () const {
635       return _state.geodetic_position_v.getLongitudeDeg();
636     }
637 
get_Phi() const638     inline double get_Phi() const { return _state.euler_angles_v[0]; }
get_Theta() const639     inline double get_Theta() const { return _state.euler_angles_v[1]; }
get_Psi() const640     inline double get_Psi() const { return _state.euler_angles_v[2]; }
get_Phi_deg() const641     inline double get_Phi_deg () const { return get_Phi() * SGD_RADIANS_TO_DEGREES; }
get_Theta_deg() const642     inline double get_Theta_deg () const { return get_Theta() * SGD_RADIANS_TO_DEGREES; }
get_Psi_deg() const643     inline double get_Psi_deg () const { return get_Psi() * SGD_RADIANS_TO_DEGREES; }
644 
645 
646     // ========== Miscellaneous quantities ==========
647 
get_Alpha() const648     inline double get_Alpha() const { return _state.alpha; }
get_Alpha_deg() const649     inline double get_Alpha_deg() const { return _state.alpha * SGD_RADIANS_TO_DEGREES; }
get_Beta() const650     inline double get_Beta() const { return _state.beta; }
get_Beta_deg() const651     inline double get_Beta_deg() const { return _state.beta * SGD_RADIANS_TO_DEGREES; }
get_Gamma_vert_rad() const652     inline double get_Gamma_vert_rad() const { return _state.gamma_vert_rad; }
653 
get_Density() const654     inline double get_Density() const { return _state.density; }
get_Mach_number() const655     inline double get_Mach_number() const { return _state.mach_number; }
656 
get_Static_pressure() const657     inline double get_Static_pressure() const { return _state.static_pressure; }
get_Total_pressure() const658     inline double get_Total_pressure() const { return _state.total_pressure; }
get_Dynamic_pressure() const659     inline double get_Dynamic_pressure() const { return _state.dynamic_pressure; }
660 
get_Static_temperature() const661     inline double get_Static_temperature() const { return _state.static_temperature; }
get_Total_temperature() const662     inline double get_Total_temperature() const { return _state.total_temperature; }
663 
get_Sea_level_radius() const664     inline double get_Sea_level_radius() const { return _state.sea_level_radius; }
get_Earth_position_angle() const665     inline double get_Earth_position_angle() const {
666         return _state.earth_position_angle;
667     }
668 
get_Runway_altitude() const669     inline double get_Runway_altitude() const { return _state.runway_altitude; }
get_Runway_altitude_m() const670     inline double get_Runway_altitude_m() const { return SG_FEET_TO_METER * _state.runway_altitude; }
671 
get_Climb_Rate() const672     inline double get_Climb_Rate() const { return _state.climb_rate; }
673 
674     // Note that currently this is the "same" value runway altitude...
get_ground_elev_ft() const675     inline double get_ground_elev_ft() const { return _state.runway_altitude; }
676 
677 
678     //////////////////////////////////////////////////////////////////////////
679     // Ground handling routines
680     //////////////////////////////////////////////////////////////////////////
681 
682     // Prepare the ground cache for the wgs84 position pt_*.
683     // That is take all vertices in the ball with radius rad around the
684     // position given by the pt_* and store them in a local scene graph.
685     bool prepare_ground_cache_m(double startSimTime, double endSimTime,
686                                 const double pt[3], double rad);
687     bool prepare_ground_cache_ft(double startSimTime, double endSimTime,
688                                  const double pt[3], double rad);
689 
690 
691     // Returns true if the cache is valid.
692     // Also the reference time, point and radius values where the cache
693     // is valid for are returned.
694     bool is_valid_m(double *ref_time, double pt[3], double *rad);
695     bool is_valid_ft(double *ref_time, double pt[3], double *rad);
696 
697     // Return the nearest catapult to the given point
698     // pt in wgs84 coordinates.
699     double get_cat_m(double t, const double pt[3],
700                      double end[2][3], double vel[2][3]);
701     double get_cat_ft(double t, const double pt[3],
702                       double end[2][3], double vel[2][3]);
703 
704 
705     // Return the orientation and position matrix and the linear and angular
706     // velocity of that local coordinate systems origin for a given time and
707     // body id. The velocities are in the wgs84 frame at the bodys origin.
708     bool get_body_m(double t, simgear::BVHNode::Id id, double bodyToWorld[16],
709                     double linearVel[3], double angularVel[3]);
710 
711 
712     // Return the altitude above ground below the wgs84 point pt
713     // Search for the nearest triangle to pt in downward direction.
714     // Return ground properties. The velocities are in the wgs84 frame at the
715     // contact point.
716     bool get_agl_m(double t, const double pt[3], double max_altoff,
717                    double contact[3], double normal[3], double linearVel[3],
718                    double angularVel[3], simgear::BVHMaterial const*& material,
719                    simgear::BVHNode::Id& id);
720     bool get_agl_ft(double t, const double pt[3], double max_altoff,
721                     double contact[3], double normal[3], double linearVel[3],
722                     double angularVel[3], simgear::BVHMaterial const*& material,
723                     simgear::BVHNode::Id& id);
724     double get_groundlevel_m(double lat, double lon, double alt);
725     double get_groundlevel_m(const SGGeod& geod);
726 
727 
728     // Return the nearest point in any direction to the point pt with a maximum
729     // distance maxDist. The velocities are in the wgs84 frame at the query
730     // position pt.
731     bool get_nearest_m(double t, const double pt[3], double maxDist,
732                        double contact[3], double normal[3], double linearVel[3],
733                        double angularVel[3], simgear::BVHMaterial const*& material,
734                        simgear::BVHNode::Id& id);
735     bool get_nearest_ft(double t, const double pt[3], double maxDist,
736                         double contact[3], double normal[3],double linearVel[3],
737                         double angularVel[3], simgear::BVHMaterial const*& material,
738                         simgear::BVHNode::Id& id);
739 
740 
741     // Return 1 if the hook intersects with a wire.
742     // That test is done by checking if the quad spanned by the points pt*
743     // intersects with the line representing the wire.
744     // If the wire is caught, the cache will trace this wires endpoints until
745     // the FDM calls release_wire().
746     bool caught_wire_m(double t, const double pt[4][3]);
747     bool caught_wire_ft(double t, const double pt[4][3]);
748 
749     // Return the location and speed of the wire endpoints.
750     bool get_wire_ends_m(double t, double end[2][3], double vel[2][3]);
751     bool get_wire_ends_ft(double t, double end[2][3], double vel[2][3]);
752 
753     // Tell the cache code that it does no longer need to care for
754     // the wire end position.
755     void release_wire(void);
756 
757     // Manages the AI wake computations.
add_ai_wake(FGAIAircraft * ai)758     void add_ai_wake(FGAIAircraft* ai) { wake_group.AddAI(ai); }
reset_wake_group(void)759     void reset_wake_group(void) { wake_group.gc(); }
get_wake_group(void)760     const AIWakeGroup& get_wake_group(void) { return wake_group; }
761 };
762 
763 #endif // _FLIGHT_HXX
764