#include <simgear/constants.h>
#include <Aircraft/aircraft.hxx>
-#ifdef FG_WEATHERCM
-# include <WeatherCM/FGLocalWeatherDatabase.h>
-#endif
#include "BalloonSim.h"
/* later, but currently was my main concern to get it going... */
/************************************************************************/
-#ifdef FG_WEATHERCM
- sgVec3 v;
-
- FGPhysicalProperty wdbpos = WeatherDatabase->get(position);
-
- //get the current wind velocity and store it in v
- //Point3D temp = wdbpos.Wind;
- //sgSetVec3(v, temp.x(), temp.y(), temp.z());
- sgCopyVec3(v, wdbpos.Wind );
-
- sgSubVec3(v, velocity);
- float speed = sgLengthVec3(v);
-
- // calculate the density of the gas inside
- double rho = wdbpos.AirPressure / (287.14 * T);
-
- // calculate the mass of the air
- double mAir = rho * balloon_envelope_volume;
-
- // loss of energy by cooling down:
- float k = 1.0 / (1.0/4.8 + 1.0/(4.8+3.4*speed) + l_of_the_envelope/lambda);
- float Q = k * balloon_envelope_area * (dt/3600.0) * (wdbpos.Temperature - T); //(dt/3600.0) = time since last call in hours
-
-#else
// I realy don't think there is a solution for this without WeatherCM
// but this is a hack, and it's working -- EMH
double mAir = 0;
float Q = 0;
-#endif
// gain of energy by heating:
if (fuel_left > 0.0) //but only with some fuel left ;-)
sgVec3 fTotal, fFriction, fLift;
sgScaleVec3(fTotal, gravity_vector, mTotal);
-#ifdef FG_WEATHERCM
- sgScaleVec3(fFriction, v, cw_envelope * wind_facing_area_of_balloon * WeatherDatabase->getAirDensity(position) * speed / 2.0); //wind resistance
- sgScaleVec3(fLift, gravity_vector, -balloon_envelope_volume * wdbpos.AirPressure / (287.14 * wdbpos.Temperature));
-#endif
sgAddVec3(fTotal, fLift);
sgAddVec3(fTotal, fFriction);