#include <Math/fg_geodesy.hxx>
+// base_fdm_state is the internal state that is updated in integer
+// multiples of "dt". This leads to "jitter" with respect to the real
+// world time, so we introduce cur_fdm_state which is extrapolated by
+// the difference between sim time and real world time
+
FGState cur_fdm_state;
+FGState base_fdm_state;
// Initialize the flight model parameters
int fgFlightModelInit(int model, FGState& f, double dt) {
double save_alt = 0.0;
- int result;
FG_LOG( FG_FLIGHT ,FG_INFO, "Initializing flight model" );
+ base_fdm_state = f;
+
if ( model == FGState::FG_SLEW ) {
// fgSlewInit(dt);
} else if ( model == FGState::FG_LARCSIM ) {
+
// lets try to avoid really screwing up the LaRCsim model
- if ( f.get_Altitude() < -9000.0 ) {
- save_alt = f.get_Altitude();
- f.set_Altitude( 0.0 );
+ if ( base_fdm_state.get_Altitude() < -9000.0 ) {
+ save_alt = base_fdm_state.get_Altitude();
+ base_fdm_state.set_Altitude( 0.0 );
}
- FGState_2_LaRCsim(f); // translate FG to LaRCsim structure
+ // translate FG to LaRCsim structure
+ FGState_2_LaRCsim(base_fdm_state);
+
+ // initialize LaRCsim
fgLaRCsimInit(dt);
- FG_LOG( FG_FLIGHT, FG_INFO, "FG pos = " << f.get_Latitude() );
- fgLaRCsim_2_FGState(f); // translate LaRCsim back to FG structure
+
+ FG_LOG( FG_FLIGHT, FG_INFO, "FG pos = " <<
+ base_fdm_state.get_Latitude() );
+
+ // translate LaRCsim back to FG structure
+ fgLaRCsim_2_FGState(base_fdm_state);
// but lets restore our original bogus altitude when we are done
if ( save_alt < -9000.0 ) {
- f.set_Altitude( save_alt );
+ base_fdm_state.set_Altitude( save_alt );
}
} else if ( model == FGState::FG_EXTERNAL ) {
- fgExternalInit(f, dt);
+ fgExternalInit(base_fdm_state, dt);
} else {
FG_LOG( FG_FLIGHT, FG_WARN,
"Unimplemented flight model == " << model );
}
- result = 1;
+ f = base_fdm_state;
- return(result);
+ return 1;
}
// Run multiloop iterations of the flight model
-int fgFlightModelUpdate(int model, FGState& f, int multiloop) {
+int fgFlightModelUpdate(int model, FGState& f, int multiloop, int jitter) {
double time_step, start_elev, end_elev;
- int result;
+
// printf("Altitude = %.2f\n", FG_Altitude * 0.3048);
+ // base_fdm_state = f;
+
time_step = (1.0 / DEFAULT_MODEL_HZ) * multiloop;
- start_elev = f.get_Altitude();
+ start_elev = base_fdm_state.get_Altitude();
if ( model == FGState::FG_SLEW ) {
// fgSlewUpdate(f, multiloop);
} else if ( model == FGState::FG_LARCSIM ) {
- fgLaRCsimUpdate(f, multiloop);
+ fgLaRCsimUpdate(base_fdm_state, multiloop);
} else if ( model == FGState::FG_EXTERNAL ) {
// fgExternalUpdate(f, multiloop);
} else {
"Unimplemented flight model == " << model );
}
- end_elev = f.get_Altitude();
+ end_elev = base_fdm_state.get_Altitude();
if ( time_step > 0.0 ) {
// feet per second
- f.set_Climb_Rate( (end_elev - start_elev) / time_step );
+ base_fdm_state.set_Climb_Rate( (end_elev - start_elev) / time_step );
}
- result = 1;
+ f = base_fdm_state;
- return(result);
+ return 1;
}
// Set the altitude (force)
-void fgFlightModelSetAltitude(int model, FGState& f, double alt_meters) {
+void fgFlightModelSetAltitude(int model, double alt_meters) {
double sea_level_radius_meters;
double lat_geoc;
+
// Set the FG variables first
- fgGeodToGeoc( f.get_Latitude(), alt_meters,
+ fgGeodToGeoc( base_fdm_state.get_Latitude(), alt_meters,
&sea_level_radius_meters, &lat_geoc);
- f.set_Altitude( alt_meters * METER_TO_FEET );
- f.set_Radius_to_vehicle( f.get_Altitude() +
- (sea_level_radius_meters * METER_TO_FEET) );
+ base_fdm_state.set_Altitude( alt_meters * METER_TO_FEET );
+ base_fdm_state.set_Radius_to_vehicle( base_fdm_state.get_Altitude() +
+ (sea_level_radius_meters *
+ METER_TO_FEET) );
// additional work needed for some flight models
if ( model == FGState::FG_LARCSIM ) {
- ls_ForceAltitude( f.get_Altitude() );
+ ls_ForceAltitude( base_fdm_state.get_Altitude() );
}
-
}
// $Log$
+// Revision 1.8 1999/01/08 03:23:51 curt
+// Beginning work on compensating for sim time vs. real world time "jitter".
+//
// Revision 1.7 1998/12/18 23:37:07 curt
// Collapsed out the FGState variables not currently needed. They are just
// commented out and can be readded easily at any time. The point of this
// Update internal time dependent calculations (i.e. flight model)
-void fgUpdateTimeDepCalcs(int multi_loop) {
+void fgUpdateTimeDepCalcs(int multi_loop, int remainder) {
FGState *f = current_aircraft.fdm_state;
fgLIGHT *l = &cur_light_params;
fgTIME *t = &cur_time_params;
// printf("updating flight model x %d\n", multi_loop);
fgFlightModelUpdate( current_options.get_flight_model(),
- cur_fdm_state, multi_loop );
+ cur_fdm_state, multi_loop, remainder );
} else {
fgFlightModelUpdate( current_options.get_flight_model(),
- cur_fdm_state, 0 );
+ cur_fdm_state, 0, remainder );
}
// update the view angle
void fgInitTimeDepCalcs( void ) {
// initialize timer
-#ifdef HAVE_SETITIMER
- fgTimerInit( 1.0 / DEFAULT_TIMER_HZ, fgUpdateTimeDepCalcs );
-#endif HAVE_SETITIMER
-
+ // #ifdef HAVE_SETITIMER
+ // fgTimerInit( 1.0 / DEFAULT_TIMER_HZ, fgUpdateTimeDepCalcs );
+ // #endif HAVE_SETITIMER
}
static const double alt_adjust_ft = 3.758099;
scenery.cur_elev + alt_adjust_m - 3.0,
scenery.cur_elev + alt_adjust_m );
fgFlightModelSetAltitude( current_options.get_flight_model(),
- cur_fdm_state,
scenery.cur_elev + alt_adjust_m );
FG_LOG( FG_ALL, FG_DEBUG,
// flight model
if ( multi_loop > 0 ) {
- fgUpdateTimeDepCalcs(multi_loop);
+ fgUpdateTimeDepCalcs(multi_loop, remainder);
} else {
FG_LOG( FG_ALL, FG_INFO, "Elapsed time is zero ... we're zinging" );
}
// $Log$
+// Revision 1.79 1999/01/08 03:23:56 curt
+// Beginning work on compensating for sim time vs. real world time "jitter".
+//
// Revision 1.78 1999/01/07 20:25:08 curt
// Updated struct fgGENERAL to class FGGeneral.
//
projects / flightgear.git / commitdiff