flightgear/src/Main/bfi.cxx

// bfi.cxx - Big Friendly Interface implementation
//
// Written by David Megginson, started February, 2000.
//
// Copyright (C) 2000  David Megginson - david@megginson.com
//
// THIS CLASS IS DEPRECATED; USE THE PROPERTY MANAGER INSTEAD.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// $Id$

#include "fgfs.hxx"

#include <simgear/constants.h>
#include <simgear/debug/logstream.hxx>
#include <simgear/ephemeris/ephemeris.hxx>
#include <simgear/math/sg_types.hxx>
#include <simgear/misc/props.hxx>
#include <simgear/timing/sg_time.hxx>

#include <Aircraft/aircraft.hxx>
#include <FDM/UIUCModel/uiuc_aircraftdir.h>
#include <Controls/controls.hxx>
#include <Autopilot/newauto.hxx>
#include <Scenery/scenery.hxx>
#include <Time/light.hxx>
#include <Time/event.hxx>
#include <Time/sunpos.hxx>
#include <Time/tmp.hxx>
#include <Cockpit/radiostack.hxx>
#include <Cockpit/panel.hxx>
#ifndef FG_OLD_WEATHER
#  include <WeatherCM/FGLocalWeatherDatabase.h>
#else
#  include <Weather/weather.hxx>
#endif

#include "globals.hxx"
#include "fg_init.hxx"
#include "fg_props.hxx"

FG_USING_NAMESPACE(std);


#include "bfi.hxx"



////////////////////////////////////////////////////////////////////////
// Static variables.
////////////////////////////////////////////////////////////////////////

				// Yech -- not thread-safe, etc. etc.
static bool _needReinit = false;
static string _temp;

static inline void needReinit ()
{
  _needReinit = true;
}


/**
 * Reinitialize FGFS to use the new BFI settings.
 */
static inline void
reinit ()
{
				// Save the state of everything
				// that's going to get clobbered
				// when we reinit the subsystems.

  FG_LOG(FG_GENERAL, FG_INFO, "Starting BFI reinit");

				// TODO: add more AP stuff
  bool apHeadingLock = FGBFI::getAPHeadingLock();
  double apHeadingMag = FGBFI::getAPHeadingMag();
  bool apAltitudeLock = FGBFI::getAPAltitudeLock();
  double apAltitude = FGBFI::getAPAltitude();
  const string &targetAirport = FGBFI::getTargetAirport();
  bool gpsLock = FGBFI::getGPSLock();
  // double gpsLatitude = FGBFI::getGPSTargetLatitude();
  // double gpsLongitude = FGBFI::getGPSTargetLongitude();

  FGBFI::setTargetAirport("");

  fgReInitSubsystems();

				// FIXME: this is wrong.
				// All of these are scheduled events,
				// and it should be possible to force
				// them all to run once.
  fgUpdateSunPos();
  fgUpdateMoonPos();
  cur_light_params.Update();
  fgUpdateLocalTime();
  fgUpdateWeatherDatabase();
  current_radiostack->search();

				// Restore all of the old states.
  FGBFI::setAPHeadingLock(apHeadingLock);
  FGBFI::setAPHeadingMag(apHeadingMag);
  FGBFI::setAPAltitudeLock(apAltitudeLock);
  FGBFI::setAPAltitude(apAltitude);
  FGBFI::setTargetAirport(targetAirport);
  FGBFI::setGPSLock(gpsLock);

  _needReinit = false;

  FG_LOG(FG_GENERAL, FG_INFO, "Ending BFI reinit");
}

// BEGIN: kludge 2000-12-07
// This is a kludge around a LaRCsim problem; see setAltitude()
// for details.
static int _altitude_countdown = 0;
static double _requested_altitude = -9999;
static bool _saved_freeze = false;
static inline void _check_altitude ()
{
  if (_altitude_countdown > 0) {
    _altitude_countdown--;
    if (_altitude_countdown == 0) {
      current_aircraft.fdm_state->set_Altitude(_requested_altitude);
      globals->set_freeze(_saved_freeze);
    }
  }
}

static int _lighting_countdown = 0;
static inline void _check_lighting ()
{
  if (_lighting_countdown > 0) {
    _lighting_countdown--;
    if (_lighting_countdown == 0)
      fgUpdateSkyAndLightingParams();
  }
}
// END: kludge


// BEGIN: kludge
// Allow the view to be set from two axes (i.e. a joystick hat)
// This needs to be in FGViewer itself, somehow.
static double axisLong = 0.0;
static double axisLat = 0.0;

static inline void
_set_view_from_axes ()
{
				// Take no action when hat is centered
  if (axisLong == 0 && axisLat == 0)
    return;

  double viewDir = 0;

  if (axisLong < 0) {		// Longitudinal axis forward
    if (axisLat < 0)
      viewDir = 45;
    else if (axisLat > 0)
      viewDir = 315;
    else
      viewDir = 0;
  } else if (axisLong > 0) {	// Longitudinal axis backward
    if (axisLat < 0)
      viewDir = 135;
    else if (axisLat > 0)
      viewDir = 225;
    else
      viewDir = 180;
  } else {			// Longitudinal axis neutral
    if (axisLat < 0)
      viewDir = 90;
    else
      viewDir = 270;
  }

  globals->get_current_view()->set_goal_view_offset(viewDir*DEG_TO_RAD);
//   globals->get_current_view()->set_view_offset(viewDir*DEG_TO_RAD);
}

// END: kludge



////////////////////////////////////////////////////////////////////////
// Local functions
////////////////////////////////////////////////////////////////////////

/**
 * Initialize the BFI by binding its functions to properties.
 *
 * TODO: perhaps these should migrate into the individual modules
 * (i.e. they should register themselves).
 */
void
FGBFI::init ()
{
  FG_LOG(FG_GENERAL, FG_INFO, "Starting BFI init");
				// Simulation
  fgTie("/sim/flight-model", getFlightModel, setFlightModel);
  fgTie("/sim/aircraft", getAircraft, setAircraft);
  fgTie("/sim/aircraft-dir", getAircraftDir, setAircraftDir);
  fgTie("/sim/time/gmt", getDateString, setDateString);
  fgTie("/sim/time/gmt-string", getGMTString);
  fgTie("/sim/hud/visibility", getHUDVisible, setHUDVisible);

				// Position
  fgTie("/position/airport-id", getTargetAirport, setTargetAirport);
  fgTie("/position/latitude", getLatitude, setLatitude);
  fgTie("/position/longitude", getLongitude, setLongitude);
  fgTie("/position/altitude", getAltitude, setAltitude);
  fgTie("/position/altitude-agl", getAGL);

				// Orientation
  fgTie("/orientation/heading", getHeading, setHeading);
  fgTie("/orientation/heading-magnetic", getHeadingMag);
  fgTie("/orientation/pitch", getPitch, setPitch);
  fgTie("/orientation/roll", getRoll, setRoll);

				// Engine
  fgTie("/engines/engine0/rpm", getRPM);
  fgTie("/engines/engine0/egt", getEGT);
  fgTie("/engines/engine0/cht", getCHT);
  fgTie("/engines/engine0/mp", getMP);

				// Velocities
  fgTie("/velocities/airspeed", getAirspeed, setAirspeed);
  fgTie("/velocities/side-slip", getSideSlip);
  fgTie("/velocities/vertical-speed", getVerticalSpeed);
  fgTie("/velocities/speed-north", getSpeedNorth);
  fgTie("/velocities/speed-east", getSpeedEast);
  fgTie("/velocities/speed-down", getSpeedDown);

				// Autopilot
  fgTie("/autopilot/locks/altitude", getAPAltitudeLock, setAPAltitudeLock);
  fgTie("/autopilot/settings/altitude", getAPAltitude, setAPAltitude);
  fgTie("/autopilot/locks/heading", getAPHeadingLock, setAPHeadingLock);
  fgTie("/autopilot/settings/heading", getAPHeading, setAPHeading);
  fgTie("/autopilot/settings/heading-magnetic",
             getAPHeadingMag, setAPHeadingMag);
  fgTie("/autopilot/locks/nav1", getAPNAV1Lock, setAPNAV1Lock);

				// Weather
  fgTie("/environment/visibility", getVisibility, setVisibility);
  fgTie("/environment/wind-north", getWindNorth, setWindNorth);
  fgTie("/environment/wind-east", getWindEast, setWindEast);
  fgTie("/environment/wind-down", getWindDown, setWindDown);

				// View
  fgTie("/sim/view/axes/long", (double(*)())0, setViewAxisLong);
  fgTie("/sim/view/axes/lat", (double(*)())0, setViewAxisLat);

  _altitude_countdown = 0;
  _needReinit = false;

  FG_LOG(FG_GENERAL, FG_INFO, "Ending BFI init");
}


/**
 * Reinitialize FGFS if required.
 *
 * Some changes (especially those in aircraft position) require that
 * FGFS be reinitialized afterwards.  Rather than reinitialize after
 * every change, the setter methods simply set a flag so that there
 * can be a single reinit at the end of the frame.
 */
void
FGBFI::update ()
{
  _check_altitude();
  _check_lighting();
  _set_view_from_axes();
  if (_needReinit) {
    reinit();
  }
}



////////////////////////////////////////////////////////////////////////
// Simulation.
////////////////////////////////////////////////////////////////////////


/**
 * Return the flight model as an integer.
 *
 * TODO: use a string instead.
 */
int
FGBFI::getFlightModel ()
{
  return globals->get_options()->get_flight_model();
}


/**
 * Return the current aircraft as a string.
 */
string
FGBFI::getAircraft ()
{
  _temp = globals->get_options()->get_aircraft();
  return _temp;
}


/**
 * Return the current aircraft directory (UIUC) as a string.
 */
string 
FGBFI::getAircraftDir ()
{
  _temp = aircraft_dir;
  return _temp;
}


/**
 * Set the flight model as an integer.
 *
 * TODO: use a string instead.
 */
void
FGBFI::setFlightModel (int model)
{
  if (getFlightModel() != model) {
    globals->get_options()->set_flight_model(model);
    needReinit();
  }
}


/**
 * Set the current aircraft.
 */
void
FGBFI::setAircraft (string aircraft)
{
  if (getAircraft() != aircraft) {
    globals->get_options()->set_aircraft(aircraft);
    needReinit();
  }
}


/**
 * Set the current aircraft directory (UIUC).
 */
void
FGBFI::setAircraftDir (string dir)
{
  if (getAircraftDir() != dir) {
    aircraft_dir = dir;
    needReinit();
  }
}


/**
 * Return the current Zulu time.
 */
string 
FGBFI::getDateString ()
{
  string out;
  char buf[64];
  struct tm * t = globals->get_time_params()->getGmt();
  sprintf(buf, "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
	  t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
	  t->tm_hour, t->tm_min, t->tm_sec);
  out = buf;
  return out;
}


/**
 * Set the current Zulu time.
 */
void
FGBFI::setDateString (string date_string)
// FGBFI::setTimeGMT (time_t time)
{
  SGTime * st = globals->get_time_params();
  struct tm * current_time = st->getGmt();
  struct tm new_time;

				// Scan for basic ISO format
				// YYYY-MM-DDTHH:MM:SS
  int ret = sscanf(date_string.c_str(), "%d-%d-%dT%d:%d:%d",
		   &(new_time.tm_year), &(new_time.tm_mon),
		   &(new_time.tm_mday), &(new_time.tm_hour),
		   &(new_time.tm_min), &(new_time.tm_sec));

				// Be pretty picky about this, so
				// that strange things don't happen
				// if the save file has been edited
				// by hand.
  if (ret != 6) {
    FG_LOG(FG_INPUT, FG_ALERT, "Date/time string " << date_string
	   << " not in YYYY-MM-DDTHH:MM:SS format; skipped");
    return;
  }

				// OK, it looks like we got six
				// values, one way or another.
  new_time.tm_year -= 1900;
  new_time.tm_mon -= 1;

				// Now, tell flight gear to use
				// the new time.  This was far
				// too difficult, by the way.
  long int warp =
    mktime(&new_time) - mktime(current_time) + globals->get_warp();
  double lon = current_aircraft.fdm_state->get_Longitude();
  double lat = current_aircraft.fdm_state->get_Latitude();
  double alt = current_aircraft.fdm_state->get_Altitude() * FEET_TO_METER;
  globals->set_warp(warp);
  st->update(lon, lat, warp);
  fgUpdateSkyAndLightingParams();
}


/**
 * Return the GMT as a string.
 */
string 
FGBFI::getGMTString ()
{
  string out;
  char buf[16];
  struct tm * t = globals->get_time_params()->getGmt();
  sprintf(buf, " %.2d:%.2d:%.2d",
	  t->tm_hour, t->tm_min, t->tm_sec);
  out = buf;
  return out;
}


/**
 * Return true if the HUD is visible.
 */
bool
FGBFI::getHUDVisible ()
{
  return globals->get_options()->get_hud_status();
}


/**
 * Ensure that the HUD is visible or hidden.
 */
void
FGBFI::setHUDVisible (bool visible)
{
  globals->get_options()->set_hud_status(visible);
}



////////////////////////////////////////////////////////////////////////
// Position
////////////////////////////////////////////////////////////////////////


/**
 * Return the current latitude in degrees (negative for south).
 */
double
FGBFI::getLatitude ()
{
  return current_aircraft.fdm_state->get_Latitude() * RAD_TO_DEG;
}


/**
 * Set the current latitude in degrees (negative for south).
 */
void
FGBFI::setLatitude (double latitude)
{
  current_aircraft.fdm_state->set_Latitude(latitude * DEG_TO_RAD);
  fgUpdateSkyAndLightingParams();
  if (_lighting_countdown <= 0)
    _lighting_countdown = 5;
}


/**
 * Return the current longitude in degrees (negative for west).
 */
double
FGBFI::getLongitude ()
{
  return current_aircraft.fdm_state->get_Longitude() * RAD_TO_DEG;
}


/**
 * Set the current longitude in degrees (negative for west).
 */
void
FGBFI::setLongitude (double longitude)
{
  current_aircraft.fdm_state->set_Longitude(longitude * DEG_TO_RAD);
  fgUpdateSkyAndLightingParams();
  if (_lighting_countdown <= 0)
    _lighting_countdown = 5;
}


/**
 * Return the current altitude in feet.
 */
double
FGBFI::getAltitude ()
{
  return current_aircraft.fdm_state->get_Altitude();
}



/**
 * Return the current altitude in above the terrain.
 */
double
FGBFI::getAGL ()
{
  return current_aircraft.fdm_state->get_Altitude()
	 - (scenery.cur_elev * METER_TO_FEET);
}


/**
 * Set the current altitude in feet.
 */
void
FGBFI::setAltitude (double altitude)
{
  current_aircraft.fdm_state->set_Altitude(altitude);

				// 2000-12-07
				// This is an ugly kludge around a
				// LaRCsim problem; if the
				// requested altitude cannot be
				// set right away (because it's
				// below the last-calculated ground
				// level), pause FGFS, wait for
				// five frames, and then try again.
  if (_altitude_countdown <= 0 &&
      fabs(getAltitude() - altitude) > 5.0) {
    _altitude_countdown = 5;
    _requested_altitude = altitude;
    _saved_freeze = globals->get_freeze();
    globals->set_freeze(true);
  }
}



////////////////////////////////////////////////////////////////////////
// Attitude
////////////////////////////////////////////////////////////////////////


/**
 * Return the current heading in degrees.
 */
double
FGBFI::getHeading ()
{
  return current_aircraft.fdm_state->get_Psi() * RAD_TO_DEG;
}


/**
 * Return the current heading in degrees.
 */
double
FGBFI::getHeadingMag ()
{
  return current_aircraft.fdm_state->get_Psi() * RAD_TO_DEG - getMagVar();
}


/**
 * Set the current heading in degrees.
 */
void
FGBFI::setHeading (double heading)
{
  FGInterface * fdm = current_aircraft.fdm_state;
  fdm->set_Euler_Angles(fdm->get_Phi(), fdm->get_Theta(),
			heading * DEG_TO_RAD);
}


/**
 * Return the current pitch in degrees.
 */
double
FGBFI::getPitch ()
{
  return current_aircraft.fdm_state->get_Theta() * RAD_TO_DEG;
}


/**
 * Set the current pitch in degrees.
 */
void
FGBFI::setPitch (double pitch)
{
  FGInterface * fdm = current_aircraft.fdm_state;
  fdm->set_Euler_Angles(fdm->get_Phi(), pitch * DEG_TO_RAD, fdm->get_Psi());
}


/**
 * Return the current roll in degrees.
 */
double
FGBFI::getRoll ()
{
  return current_aircraft.fdm_state->get_Phi() * RAD_TO_DEG;
}


/**
 * Set the current roll in degrees.
 */
void
FGBFI::setRoll (double roll)
{
  FGInterface * fdm = current_aircraft.fdm_state;
  fdm->set_Euler_Angles(roll * DEG_TO_RAD, fdm->get_Theta(), fdm->get_Psi());
}


/**
 * Return the current engine0 rpm
 */
double
FGBFI::getRPM ()
{
  if ( current_aircraft.fdm_state->get_engine(0) != NULL ) {
      return current_aircraft.fdm_state->get_engine(0)->get_RPM();
  } else {
      return 0.0;
  }
}


/**
 * Set the current engine0 rpm
 */
void
FGBFI::setRPM (double rpm)
{
    if ( current_aircraft.fdm_state->get_engine(0) != NULL ) {
	if (getRPM() != rpm) {
	    current_aircraft.fdm_state->get_engine(0)->set_RPM( rpm );
	}
    }
}


/**
 * Return the current engine0 EGT.
 */
double
FGBFI::getEGT ()
{
  if ( current_aircraft.fdm_state->get_engine(0) != NULL ) {
      return current_aircraft.fdm_state->get_engine(0)->get_EGT();
  } else {
      return 0.0;
  }
}


/**
 * Return the current engine0 CHT.
 */
double
FGBFI::getCHT ()
{
  if ( current_aircraft.fdm_state->get_engine(0) != NULL ) {
      return current_aircraft.fdm_state->get_engine(0)->get_CHT();
  } else {
      return 0.0;
  }
}


/**
 * Return the current engine0 CHT.
 */
double
FGBFI::getMP ()
{
  if ( current_aircraft.fdm_state->get_engine(0) != NULL ) {
      return current_aircraft.fdm_state->get_engine(0)->get_Manifold_Pressure();
  } else {
      return 0.0;
  }
}



////////////////////////////////////////////////////////////////////////
// Velocities
////////////////////////////////////////////////////////////////////////


/**
 * Return the current airspeed in knots.
 */
double
FGBFI::getAirspeed ()
{
				// FIXME: should we add speed-up?
  return current_aircraft.fdm_state->get_V_calibrated_kts();
}


/**
 * Set the calibrated airspeed in knots.
 */
void
FGBFI::setAirspeed (double speed)
{
  current_aircraft.fdm_state->set_V_calibrated_kts(speed);
}


/**
 * Return the current sideslip (FIXME: units unknown).
 */
double
FGBFI::getSideSlip ()
{
  return current_aircraft.fdm_state->get_Beta();
}


/**
 * Return the current climb rate in feet/minute
 */
double
FGBFI::getVerticalSpeed ()
{
				// What about meters?
  return current_aircraft.fdm_state->get_Climb_Rate() * 60.0;
}


/**
 * Get the current north velocity (units??).
 */
double
FGBFI::getSpeedNorth ()
{
  return current_aircraft.fdm_state->get_V_north();
}


// /**
//  * Set the current north velocity (units??).
//  */
// void
// FGBFI::setSpeedNorth (double speed)
// {
//   FGInterface * fdm = current_aircraft.fdm_state;
// //   fdm->set_Velocities_Local(speed, fdm->get_V_east(), fdm->get_V_down());
// }


/**
 * Get the current east velocity (units??).
 */
double
FGBFI::getSpeedEast ()
{
  return current_aircraft.fdm_state->get_V_east();
}


// /**
//  * Set the current east velocity (units??).
//  */
// void
// FGBFI::setSpeedEast (double speed)
// {
//   FGInterface * fdm = current_aircraft.fdm_state;
// //   fdm->set_Velocities_Local(fdm->get_V_north(), speed, fdm->get_V_down());
// }


/**
 * Get the current down velocity (units??).
 */
double
FGBFI::getSpeedDown ()
{
  return current_aircraft.fdm_state->get_V_down();
}


// /**
//  * Set the current down velocity (units??).
//  */
// void
// FGBFI::setSpeedDown (double speed)
// {
//   FGInterface * fdm = current_aircraft.fdm_state;
// //   fdm->set_Velocities_Local(fdm->get_V_north(), fdm->get_V_east(), speed);
// }



////////////////////////////////////////////////////////////////////////
// Controls
////////////////////////////////////////////////////////////////////////

#if 0

/**
 * Get the throttle setting, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getThrottle ()
{
				// FIXME: add engine selector
  return controls.get_throttle(0);
}


/**
 * Set the throttle, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setThrottle (double throttle)
{
				// FIXME: allow engine selection
  controls.set_throttle(0, throttle);
}


/**
 * Get the fuel mixture setting, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getMixture ()
{
				// FIXME: add engine selector
  return controls.get_mixture(0);
}


/**
 * Set the fuel mixture, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setMixture (double mixture)
{
				// FIXME: allow engine selection
  controls.set_mixture(0, mixture);
}


/**
 * Get the propellor pitch setting, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getPropAdvance ()
{
				// FIXME: add engine selector
  return controls.get_prop_advance(0);
}


/**
 * Set the propellor pitch, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setPropAdvance (double pitch)
{
				// FIXME: allow engine selection
  controls.set_prop_advance(0, pitch);
}


/**
 * Get the flaps setting, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getFlaps ()
{
  return controls.get_flaps();
}


/**
 * Set the flaps, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setFlaps (double flaps)
{
				// FIXME: clamp?
  controls.set_flaps(flaps);
}


/**
 * Get the aileron, from -1.0 (left) to 1.0 (right).
 */
double
FGBFI::getAileron ()
{
  return controls.get_aileron();
}


/**
 * Set the aileron, from -1.0 (left) to 1.0 (right).
 */
void
FGBFI::setAileron (double aileron)
{
				// FIXME: clamp?
  controls.set_aileron(aileron);
}


/**
 * Get the rudder setting, from -1.0 (left) to 1.0 (right).
 */
double
FGBFI::getRudder ()
{
  return controls.get_rudder();
}


/**
 * Set the rudder, from -1.0 (left) to 1.0 (right).
 */
void
FGBFI::setRudder (double rudder)
{
				// FIXME: clamp?
  controls.set_rudder(rudder);
}


/**
 * Get the elevator setting, from -1.0 (down) to 1.0 (up).
 */
double
FGBFI::getElevator ()
{
  return controls.get_elevator();
}


/**
 * Set the elevator, from -1.0 (down) to 1.0 (up).
 */
void
FGBFI::setElevator (double elevator)
{
				// FIXME: clamp?
  controls.set_elevator(elevator);
}


/**
 * Get the elevator trim, from -1.0 (down) to 1.0 (up).
 */
double
FGBFI::getElevatorTrim ()
{
  return controls.get_elevator_trim();
}


/**
 * Set the elevator trim, from -1.0 (down) to 1.0 (up).
 */
void
FGBFI::setElevatorTrim (double trim)
{
				// FIXME: clamp?
  controls.set_elevator_trim(trim);
}


/**
 * Get the highest brake setting, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getBrakes ()
{
  double b1 = getCenterBrake();
  double b2 = getLeftBrake();
  double b3 = getRightBrake();
  return (b1 > b2 ? (b1 > b3 ? b1 : b3) : (b2 > b3 ? b2 : b3));
}


/**
 * Set all brakes, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setBrakes (double brake)
{
  setCenterBrake(brake);
  setLeftBrake(brake);
  setRightBrake(brake);
}


/**
 * Get the center brake, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getCenterBrake ()
{
  return controls.get_brake(2);
}


/**
 * Set the center brake, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setCenterBrake (double brake)
{
  controls.set_brake(2, brake);
}


/**
 * Get the left brake, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getLeftBrake ()
{
  return controls.get_brake(0);
}


/**
 * Set the left brake, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setLeftBrake (double brake)
{
  controls.set_brake(0, brake);
}


/**
 * Get the right brake, from 0.0 (none) to 1.0 (full).
 */
double
FGBFI::getRightBrake ()
{
  return controls.get_brake(1);
}


/**
 * Set the right brake, from 0.0 (none) to 1.0 (full).
 */
void
FGBFI::setRightBrake (double brake)
{
  controls.set_brake(1, brake);
}


#endif


////////////////////////////////////////////////////////////////////////
// Autopilot
////////////////////////////////////////////////////////////////////////


/**
 * Get the autopilot altitude lock (true=on).
 */
bool
FGBFI::getAPAltitudeLock ()
{
    return current_autopilot->get_AltitudeEnabled();
}


/**
 * Set the autopilot altitude lock (true=on).
 */
void
FGBFI::setAPAltitudeLock (bool lock)
{
  current_autopilot->set_AltitudeMode(FGAutopilot::FG_ALTITUDE_LOCK);
  current_autopilot->set_AltitudeEnabled(lock);
}


/**
 * Get the autopilot target altitude in feet.
 */
double
FGBFI::getAPAltitude ()
{
  return current_autopilot->get_TargetAltitude() * METER_TO_FEET;
}


/**
 * Set the autopilot target altitude in feet.
 */
void
FGBFI::setAPAltitude (double altitude)
{
    current_autopilot->set_TargetAltitude( altitude );
}


/**
 * Get the autopilot heading lock (true=on).
 */
bool
FGBFI::getAPHeadingLock ()
{
    return
      (current_autopilot->get_HeadingEnabled() &&
       current_autopilot->get_HeadingMode() == FGAutopilot::FG_HEADING_LOCK);
}


/**
 * Set the autopilot heading lock (true=on).
 */
void
FGBFI::setAPHeadingLock (bool lock)
{
  if (lock) {
				// We need to do this so that
				// it's possible to lock onto a
				// heading other than the current
				// heading.
    double heading = getAPHeadingMag();
    current_autopilot->set_HeadingMode(FGAutopilot::FG_HEADING_LOCK);
    current_autopilot->set_HeadingEnabled(true);
    setAPHeadingMag(heading);
  } else if (current_autopilot->get_HeadingMode() ==
	     FGAutopilot::FG_HEADING_LOCK) {
    current_autopilot->set_HeadingEnabled(false);
  }
}


/**
 * Get the autopilot target heading in degrees.
 */
double
FGBFI::getAPHeading ()
{
  return current_autopilot->get_TargetHeading();
}


/**
 * Set the autopilot target heading in degrees.
 */
void
FGBFI::setAPHeading (double heading)
{
  current_autopilot->set_TargetHeading( heading );
}


/**
 * Get the autopilot target heading in degrees.
 */
double
FGBFI::getAPHeadingMag ()
{
  return current_autopilot->get_TargetHeading() - getMagVar();
}


/**
 * Set the autopilot target heading in degrees.
 */
void
FGBFI::setAPHeadingMag (double heading)
{
  current_autopilot->set_TargetHeading( heading + getMagVar() );
}


/**
 * Return true if the autopilot is locked to NAV1.
 */
bool
FGBFI::getAPNAV1Lock ()
{
  return
    (current_autopilot->get_HeadingEnabled() &&
     current_autopilot->get_HeadingMode() == FGAutopilot::FG_HEADING_NAV1);
}


/**
 * Set the autopilot NAV1 lock.
 */
void
FGBFI::setAPNAV1Lock (bool lock)
{
  if (lock) {
    current_autopilot->set_HeadingMode(FGAutopilot::FG_HEADING_NAV1);
    current_autopilot->set_HeadingEnabled(true);
  } else if (current_autopilot->get_HeadingMode() ==
	     FGAutopilot::FG_HEADING_NAV1) {
    current_autopilot->set_HeadingEnabled(false);
  }
}



////////////////////////////////////////////////////////////////////////
// GPS
////////////////////////////////////////////////////////////////////////


/**
 * Get the autopilot GPS lock (true=on).
 */
bool
FGBFI::getGPSLock ()
{
  return (current_autopilot->get_HeadingEnabled() &&
	  (current_autopilot->get_HeadingMode() ==
	   FGAutopilot::FG_HEADING_WAYPOINT ));
}


/**
 * Set the autopilot GPS lock (true=on).
 */
void
FGBFI::setGPSLock (bool lock)
{
  if (lock) {
    current_autopilot->set_HeadingMode(FGAutopilot::FG_HEADING_WAYPOINT);
    current_autopilot->set_HeadingEnabled(true);
  } else if (current_autopilot->get_HeadingMode() ==
	     FGAutopilot::FG_HEADING_WAYPOINT) {
    current_autopilot->set_HeadingEnabled(false);
  }
}


/**
 * Get the GPS target airport code.
 */
string 
FGBFI::getTargetAirport ()
{
  // FIXME: not thread-safe
  static string out;
  out = globals->get_options()->get_airport_id();

  return out;
}


/**
 * Set the GPS target airport code.
 */
void
FGBFI::setTargetAirport (string airportId)
{
  globals->get_options()->set_airport_id(airportId);
}


/**
 * Get the GPS target latitude in degrees (negative for south).
 */
double
FGBFI::getGPSTargetLatitude ()
{
    return current_autopilot->get_TargetLatitude();
}


/**
 * Get the GPS target longitude in degrees (negative for west).
 */
double
FGBFI::getGPSTargetLongitude ()
{
  return current_autopilot->get_TargetLongitude();
}

#if 0
/**
 * Set the GPS target longitude in degrees (negative for west).
 */
void
FGBFI::setGPSTargetLongitude (double longitude)
{
  current_autopilot->set_TargetLongitude( longitude );
}
#endif



////////////////////////////////////////////////////////////////////////
// Weather
////////////////////////////////////////////////////////////////////////


/**
 * Get the current visibility (meters).
 */
double
FGBFI::getVisibility ()
{
#ifndef FG_OLD_WEATHER
  return WeatherDatabase->getWeatherVisibility();
#else
  return current_weather.get_visibility();
#endif
}


/**
 * Set the current visibility (meters).
 */
void
FGBFI::setVisibility (double visibility)
{
#ifndef FG_OLD_WEATHER
  WeatherDatabase->setWeatherVisibility(visibility);
#else
  current_weather.set_visibility(visibility);
#endif
}


/**
 * Get the current wind north velocity (feet/second).
 */
double
FGBFI::getWindNorth ()
{
  return current_aircraft.fdm_state->get_V_north_airmass();
}


/**
 * Set the current wind north velocity (feet/second).
 */
void
FGBFI::setWindNorth (double speed)
{
  current_aircraft.fdm_state->set_Velocities_Local_Airmass(speed,
							   getWindEast(),
							   getWindDown());
}


/**
 * Get the current wind east velocity (feet/second).
 */
double
FGBFI::getWindEast ()
{
  return current_aircraft.fdm_state->get_V_east_airmass();
}


/**
 * Set the current wind east velocity (feet/second).
 */
void
FGBFI::setWindEast (double speed)
{
  cout << "Set wind-east to " << speed << endl;
  current_aircraft.fdm_state->set_Velocities_Local_Airmass(getWindNorth(),
							   speed,
							   getWindDown());
}


/**
 * Get the current wind down velocity (feet/second).
 */
double
FGBFI::getWindDown ()
{
  return current_aircraft.fdm_state->get_V_down_airmass();
}


/**
 * Set the current wind down velocity (feet/second).
 */
void
FGBFI::setWindDown (double speed)
{
  current_aircraft.fdm_state->set_Velocities_Local_Airmass(getWindNorth(),
							   getWindEast(),
							   speed);
}



////////////////////////////////////////////////////////////////////////
// View.
////////////////////////////////////////////////////////////////////////

void
FGBFI::setViewAxisLong (double axis)
{
  axisLong = axis;
}

void
FGBFI::setViewAxisLat (double axis)
{
  axisLat = axis;
}


////////////////////////////////////////////////////////////////////////
// Time
////////////////////////////////////////////////////////////////////////

/**
 * Return the magnetic variation
 */
double
FGBFI::getMagVar ()
{
  return globals->get_mag()->get_magvar() * RAD_TO_DEG;
}


/**
 * Return the magnetic variation
 */
double
FGBFI::getMagDip ()
{
  return globals->get_mag()->get_magdip() * RAD_TO_DEG;
}


// end of bfi.cxx