#include "FGPhysicalProperties.h"
#include "FGWeatherDefs.h"
+#include "FGWeatherUtils.h"
+
/****************************************************************************/
/********************************** CODE ************************************/
/****************************************************************************/
AirPressure = FGAirPressureItem(101325.0);
- VaporPressure[ 0.0] = FG_WEATHER_DEFAULT_VAPORPRESSURE; //in Pa (I *only* accept SI!)
+ VaporPressure[-1000.0] = FG_WEATHER_DEFAULT_VAPORPRESSURE; //in Pa (I *only* accept SI!)
VaporPressure[10000.0] = FG_WEATHER_DEFAULT_VAPORPRESSURE; //in Pa (I *only* accept SI!)
//Clouds.insert(FGCloudItem()) => none
LightningProbability = 0.0;
}
+/*
+The Methods:
+
+ WeatherPrecision getWind_x( int number ) const;
+ WeatherPrecision getWind_y( int number ) const;
+ WeatherPrecision getWind_z( int number ) const;
+ WeatherPrecision getWind_a( int number ) const;
+ void setWind_x( int number, WeatherPrecision x);
+ void setWind_y( int number, WeatherPrecision y);
+ void setWind_z( int number, WeatherPrecision z);
+ void setWind_a( int number, WeatherPrecision a);
+ WeatherPrecision getTurbulence_x( int number ) const;
+ WeatherPrecision getTurbulence_y( int number ) const;
+ WeatherPrecision getTurbulence_z( int number ) const;
+ WeatherPrecision getTurbulence_a( int number ) const;
+ void setTurbulence_x( int number, WeatherPrecision x);
+ void setTurbulence_y( int number, WeatherPrecision y);
+ void setTurbulence_z( int number, WeatherPrecision z);
+ void setTurbulence_a( int number, WeatherPrecision a);
+ WeatherPrecision getTemperature_x( int number ) const;
+ WeatherPrecision getTemperature_a( int number ) const;
+ void setTemperature_x( int number, WeatherPrecision x);
+ void setTemperature_a( int number, WeatherPrecision a);
+ WeatherPrecision getVaporPressure_x( int number ) const;
+ WeatherPrecision getVaporPressure_a( int number ) const;
+ void setVaporPressure_x( int number, WeatherPrecision x);
+ void setVaporPressure_a( int number, WeatherPrecision a);
+
+are in the extra file FGPhysicalProperties_bind.cpp
+*/
+
unsigned int FGPhysicalProperties::getNumberOfCloudLayers(void) const
{
return Clouds.size();
return CloudsIt->second;
}
+ostream& operator<< ( ostream& out, const FGPhysicalProperties2D& p )
+{
+ typedef map<FGPhysicalProperties::Altitude, FGWindItem >::const_iterator wind_iterator;
+ typedef map<FGPhysicalProperties::Altitude, FGTurbulenceItem>::const_iterator turbulence_iterator;
+ typedef map<FGPhysicalProperties::Altitude, WeatherPrecision>::const_iterator scalar_iterator;
+
+ out << "Position: (" << p.p[0] << ", " << p.p[1] << ", " << p.p[2] << ")\n";
+
+ out << "Stored Wind: ";
+ for (wind_iterator WindIt = p.Wind.begin();
+ WindIt != p.Wind.end();
+ WindIt++)
+ out << "(" << WindIt->second.x() << ", " << WindIt->second.y() << ", " << WindIt->second.z() << ") m/s at (" << WindIt->first << ") m; ";
+ out << "\n";
+ out << "Stored Turbulence: ";
+ for (turbulence_iterator TurbulenceIt = p.Turbulence.begin();
+ TurbulenceIt != p.Turbulence.end();
+ TurbulenceIt++)
+ out << "(" << TurbulenceIt->second.x() << ", " << TurbulenceIt->second.y() << ", " << TurbulenceIt->second.z() << ") m/s at (" << TurbulenceIt->first << ") m; ";
+ out << "\n";
+ out << "Stored Temperature: ";
+ for (scalar_iterator TemperatureIt = p.Temperature.begin();
+ TemperatureIt != p.Temperature.end();
+ TemperatureIt++)
+ out << Kelvin2Celsius(TemperatureIt->second) << " degC at " << TemperatureIt->first << "m; ";
+ out << "\n";
+ out << "Stored AirPressure: ";
+ out << p.AirPressure.getValue()/100.0 << " hPa at " << 0.0 << "m; ";
+ out << "\n";
+ out << "Stored VaporPressure: ";
+ for (scalar_iterator VaporPressureIt = p.VaporPressure.begin();
+ VaporPressureIt != p.VaporPressure.end();
+ VaporPressureIt++)
+ out << VaporPressureIt->second/100.0 << " hPa at " << VaporPressureIt->first << "m; ";
+ out << "\n";
+
+ return out << "\n";
+}
+
+
+inline double F(const WeatherPrecision factor, const WeatherPrecision a, const WeatherPrecision b, const WeatherPrecision r, const WeatherPrecision x)
+{
+ const double c = 1.0 / (-b + a * r);
+ return factor * c * ( 1.0 / (r + x) + a * c * log(fabs((r + x) * (b + a * x))) );
+}
+
+WeatherPrecision FGPhysicalProperties::AirPressureAt(const WeatherPrecision x) const
+{
+ const double rho0 = (AirPressure.getValue()*FG_WEATHER_DEFAULT_AIRDENSITY*FG_WEATHER_DEFAULT_TEMPERATURE)/(TemperatureAt(0)*FG_WEATHER_DEFAULT_AIRPRESSURE);
+ const double G = 6.673e-11; //Gravity; in m^3 kg^-1 s^-2
+ const double m = 5.977e24; //mass of the earth in kg
+ const double r = 6368e3; //radius of the earth in metres
+ const double factor = -(rho0 * TemperatureAt(0) * G * m) / AirPressure.getValue();
+
+ double a, b, FF = 0.0;
+
+ //ok, integrate from 0 to a now.
+ if (Temperature.size() < 2)
+ { //take care of the case that there aren't enough points
+ //actually this should be impossible...
+
+ if (Temperature.size() == 0)
+ {
+ cerr << "ERROR in FGPhysicalProperties: Air pressure at " << x << " metres altiude requested,\n";
+ cerr << " but there isn't enough data stored! No temperature is aviable!\n";
+ return FG_WEATHER_DEFAULT_AIRPRESSURE;
+ }
+
+ //ok, I've got only one point. So I'm assuming that that temperature is
+ //the same for all altitudes.
+ a = 1;
+ b = TemperatureAt(0);
+ FF += F(factor, a, b, r, x );
+ FF -= F(factor, a, b, r, 0.0);
+ }
+ else
+ { //I've got at least two entries now
+
+ //integrate 'backwards' by integrating the strip ]n,x] first, then ]n-1,n] ... to [0,n-m]
+
+ if (x>=0.0)
+ {
+ map<WeatherPrecision, WeatherPrecision>::const_iterator temp2 = Temperature.upper_bound(x);
+ map<WeatherPrecision, WeatherPrecision>::const_iterator temp1 = temp2; temp1--;
+
+ if (temp1->first == x)
+ { //ignore that interval
+ temp1--; temp2--;
+ }
+
+ bool first_pass = true;
+ while(true)
+ {
+ if (temp2 == Temperature.end())
+ {
+ //temp2 doesn't exist. So cheat by assuming that the slope is the
+ //same as between the two earlier temperatures
+ temp1--; temp2--;
+ a = (temp2->second - temp1->second)/(temp2->first - temp1->first);
+ b = temp1->second - a * temp1->first;
+ temp1++; temp2++;
+ }
+ else
+ {
+ a = (temp2->second - temp1->second)/(temp2->first - temp1->first);
+ b = temp1->second - a * temp1->first;
+ }
+
+ if (first_pass)
+ {
+
+ FF += F(factor, a, b, r, x);
+ first_pass = false;
+ }
+ else
+ {
+ FF += F(factor, a, b, r, temp2->first);
+ }
+
+ if (temp1->first>0.0)
+ {
+ FF -= F(factor, a, b, r, temp1->first);
+ temp1--; temp2--;
+ }
+ else
+ {
+ FF -= F(factor, a, b, r, 0.0);
+ return AirPressure.getValue() * exp(FF);
+ }
+ }
+ }
+ else
+ { //ok x is smaller than 0.0, so do everything in reverse
+ map<WeatherPrecision, WeatherPrecision>::const_iterator temp2 = Temperature.upper_bound(x);
+ map<WeatherPrecision, WeatherPrecision>::const_iterator temp1 = temp2; temp1--;
+
+ bool first_pass = true;
+ while(true)
+ {
+ if (temp2 == Temperature.begin())
+ {
+ //temp1 doesn't exist. So cheat by assuming that the slope is the
+ //same as between the two earlier temperatures
+ temp1 = Temperature.begin(); temp2++;
+ a = (temp2->second - temp1->second)/(temp2->first - temp1->first);
+ b = temp1->second - a * temp1->first;
+ temp2--;
+ }
+ else
+ {
+ a = (temp2->second - temp1->second)/(temp2->first - temp1->first);
+ b = temp1->second - a * temp1->first;
+ }
+
+ if (first_pass)
+ {
+
+ FF += F(factor, a, b, r, x);
+ first_pass = false;
+ }
+ else
+ {
+ FF += F(factor, a, b, r, temp2->first);
+ }
+
+ if (temp2->first<0.0)
+ {
+ FF -= F(factor, a, b, r, temp1->first);
+
+ if (temp2 == Temperature.begin())
+ {
+ temp1 = Temperature.begin(); temp2++;
+ }
+ else
+ {
+ temp1++; temp2++;
+ }
+ }
+ else
+ {
+ FF -= F(factor, a, b, r, 0.0);
+ return AirPressure.getValue() * exp(FF);
+ }
+ }
+ }
+ }
+
+ return AirPressure.getValue() * exp(FF);
+}
projects / flightgear.git / blobdiff