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Patch from Julian Foad:

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- tidies up the update-time-step handling (making it a simple "dt");
- makes the altimeter get a proper pressure, and the (unused) vacuum
  calculation get a proper RPM (*);
- replaces property name look-ups with static pointers to property nodes.

Notes from DPM:

- the static pointers are a very bad idea, but they're only temporary;
  I plan to make FGSteam into a proper subsystem soon, and then they
  can be member variables
- I fixed the patch to get the current static pressure from the
  /environment/pressure-inhg property, so that the altimeter interacts
  properly with FGEnvironment
This commit is contained in:
david 2002-07-07 13:29:52 +00:00
parent ee8c5d0a3a
commit bf58dbd3c9
2 changed files with 38 additions and 19 deletions
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55
src/Cockpit/steam.cxx
View file

@ -31,6 +31,12 @@
#include <simgear/math/sg_types.hxx>
#include <simgear/misc/props.hxx>
#include <Aircraft/aircraft.hxx>
#ifdef FG_WEATHERCM
# include <WeatherCM/FGLocalWeatherDatabase.h>
#else
# include <Environment/environment_mgr.hxx>
# include <Environment/environment.hxx>
#endif
SG_USING_NAMESPACE(std);
@ -92,7 +98,7 @@ double FGSteam::get_TC_std () { _CatchUp(); return the_TC_std; }
////////////////////////////////////////////////////////////////////////
int FGSteam::_UpdatesPending = 1000000; /* Forces filter to reset */
double FGSteam::_UpdateTimePending = 1000000; /* Forces filters to reset */
// FIXME: no need to use static
@ -100,7 +106,6 @@ int FGSteam::_UpdatesPending = 1000000; /* Forces filter to reset */
void FGSteam::update (double dt)
{
int timesteps = int(dt * fgGetInt("/sim/model-hz")); // FIXME
if (!isTied) {
isTied = true;
fgTie("/steam/airspeed-kt", FGSteam::get_ASI_kias);
@ -128,7 +133,7 @@ void FGSteam::update (double dt)
fgTie("/steam/mag-compass-deg", FGSteam::get_MH_deg);
fgSetArchivable("/steam/mag-compass-deg");
}
_UpdatesPending += timesteps;
_UpdateTimePending += dt;
}
@ -200,9 +205,15 @@ double altFtToPressInHg(double alt_ft)
void FGSteam::_CatchUp()
{ if ( _UpdatesPending != 0 )
{ double dt = _UpdatesPending * 1.0 /
fgGetInt("/sim/model-hz"); // FIXME: inefficient
{
static const SGPropertyNode *heading_deg_node = fgGetNode("/orientation/heading-deg", true);
static const SGPropertyNode *mag_var_deg_node = fgGetNode("/environment/magnetic-variation-deg", true);
static const SGPropertyNode *mag_dip_deg_node = fgGetNode("/environment/magnetic-dip-deg", true);
static const SGPropertyNode *enginge_0_rpm_node = fgGetNode("/engines/engine[0]/rpm", true);
if ( _UpdateTimePending != 0 )
{
double dt = _UpdateTimePending;
double AccN, AccE, AccU;
/* int i, j; */
double d, the_ENGINE_rpm;
@ -252,20 +263,20 @@ void FGSteam::_CatchUp()
AccN = current_aircraft.fdm_state->get_V_dot_north();
AccE = current_aircraft.fdm_state->get_V_dot_east();
AccU = current_aircraft.fdm_state->get_V_dot_down()
- 9.81 / 0.3;
- 9.81 * SG_METER_TO_FEET;
if ( fabs(the_TC_rad) > 0.2 /* 2.0 */ )
{ /* Massive sideslip jams it; it stops turning */
the_MH_degps = 0.0;
the_MH_err = fgGetDouble("/orientation/heading-deg") - the_MH_deg;
the_MH_err = heading_deg_node->getDoubleValue() - the_MH_deg;
} else
{ double MagDip, MagVar, CosDip;
double FrcN, FrcE, FrcU, AccTot;
double EdgN, EdgE, EdgU;
double TrqN, TrqE, TrqU, Torque;
/* Find a force vector towards exact magnetic north */
MagVar = fgGetDouble("/environment/magnetic-variation-deg")
MagVar = mag_var_deg_node->getDoubleValue()
/ SGD_RADIANS_TO_DEGREES;
MagDip = fgGetDouble("/environment/magnetic-dip-deg")
MagDip = mag_var_deg_node->getDoubleValue()
/ SGD_RADIANS_TO_DEGREES;
CosDip = cos ( MagDip );
FrcN = CosDip * cos ( MagVar );
@ -296,7 +307,7 @@ void FGSteam::_CatchUp()
}
if ( the_MH_err > 180.0 ) the_MH_err -= 360.0; else
if ( the_MH_err < -180.0 ) the_MH_err += 360.0;
the_MH_deg = fgGetDouble("/orientation/heading-deg") - the_MH_err;
the_MH_deg = heading_deg_node->getDoubleValue() - the_MH_err;
}
/**************************
@ -304,16 +315,24 @@ void FGSteam::_CatchUp()
scaling capability for the vacuum pump later on.
When we have a real engine model, we can ask it.
*/
the_ENGINE_rpm = globals->get_controls()->get_throttle(0) * 26.0;
the_ENGINE_rpm = enginge_0_rpm_node->getDoubleValue();
/**************************
First, we need to know what the static line is reporting,
which is a whole simulation area in itself. For now, we cheat.
which is a whole simulation area in itself.
We filter the actual value by one second to
account for the line impedance of the plumbing.
*/
double static_inhg
= altFtToPressInHg(fgGetDouble("/position/altitude-ft"));
#ifdef FG_WEATHERCM
sgVec3 plane_pos = { cur_fdm_state->get_Latitude(),
cur_fdm_state->get_Longitude(),
cur_fdm_state->get_Altitude() * SG_FEET_TO_METER };
double static_inhg = WeatherDatabase->get(plane_pos).AirPressure *
(0.01 / INHG_TO_MB);
#else
double static_inhg = fgGetDouble("/environment/pressure-inhg");
#endif
set_lowpass ( & the_STATIC_inhg, static_inhg, dt );
/*
@ -372,16 +391,16 @@ void FGSteam::_CatchUp()
> have it tumble when you exceed the usual pitch or bank limits,
> put in those insidious turning errors ... for now anyway.
*/
if ( _UpdatesPending > 999999 )
if ( _UpdateTimePending > 999999 )
the_DG_err = fgGetDouble("/environment/magnetic-variation-deg");
the_DG_degps = 0.01; /* HACK! */
if (dt<1.0) the_DG_err += dt * the_DG_degps;
the_DG_deg = fgGetDouble("/orientation/heading-deg") - the_DG_err;
the_DG_deg = heading_deg_node->getDoubleValue() - the_DG_err;
/**************************
Finished updates, now clear the timer
*/
_UpdatesPending = 0;
_UpdateTimePending = 0;
} else {
// cout << "0 Updates pending" << endl;
}

2
src/Cockpit/steam.hxx
View file

@ -92,7 +92,7 @@ private:
static double the_MH_deg, the_MH_degps, the_MH_err;
static double the_DG_deg, the_DG_degps, the_DG_inhg, the_DG_err;
static int _UpdatesPending;
static double _UpdateTimePending;
static void _CatchUp ();
static void set_lowpass ( double *outthe,