]> git.mxchange.org Git - flightgear.git/blobdiff - src/WeatherCM/FGPhysicalProperties.cpp
Erik Hofman:
[flightgear.git] / src / WeatherCM / FGPhysicalProperties.cpp
index 3acb90cb25189f8f7b86719d4cf070bc830c45fb..636ff130e9b1661f1c3cd5070101943493d120d2 100644 (file)
@@ -5,7 +5,7 @@
  Date started: 28.05.99
  Called by:    main program
 
- ---------- Copyright (C) 1999  Christian Mayer (vader@t-online.de) ----------
+ -------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
 
  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
@@ -35,6 +35,8 @@ HISTORY
 20.06.1999 Christian Mayer     added lots of consts
 11.10.1999 Christian Mayer     changed set<> to map<> on Bernie Bright's 
                                suggestion
+19.10.1999 Christian Mayer     change to use PLIB's sg instead of Point[2/3]D
+                               and lots of wee code cleaning
 *****************************************************************************/
 
 /****************************************************************************/
@@ -43,20 +45,24 @@ HISTORY
 #include "FGPhysicalProperties.h"
 #include "FGWeatherDefs.h"
 
+#include "FGWeatherUtils.h"
+
 /****************************************************************************/
 /********************************** CODE ************************************/
 /****************************************************************************/
 FGPhysicalProperties::FGPhysicalProperties()
 {
+    sgVec3 zero;
+    sgZeroVec3( zero );
     /************************************************************************/
     /* This standart constructor fills the class with a standard weather    */
     /************************************************************************/
 
-    Wind[-1000.0] = Point3D(0.0);      //no Wind by default
-    Wind[10000.0] = Point3D(0.0);      //no Wind by default
+    Wind[-1000.0] = FGWindItem(zero);              //no Wind by default
+    Wind[10000.0] = FGWindItem(zero);              //no Wind by default
 
-    Turbulence[-1000.0] = Point3D(0.0);        //no Turbulence by default
-    Turbulence[10000.0] = Point3D(0.0);        //no Turbulence by default
+    Turbulence[-1000.0] = FGTurbulenceItem(zero);   //no Turbulence by default
+    Turbulence[10000.0] = FGTurbulenceItem(zero);   //no Turbulence by default
 
     //Initialice with the CINA atmosphere
     Temperature[    0.0] = +15.0 + 273.16;  
@@ -65,7 +71,7 @@ FGPhysicalProperties::FGPhysicalProperties()
 
     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
@@ -74,6 +80,37 @@ FGPhysicalProperties::FGPhysicalProperties()
     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();
@@ -81,7 +118,7 @@ unsigned int FGPhysicalProperties::getNumberOfCloudLayers(void) const
 
 FGCloudItem FGPhysicalProperties::getCloudLayer(unsigned int nr) const
 {
-    map<WeatherPrecition,FGCloudItem>::const_iterator CloudsIt = Clouds.begin();
+    map<WeatherPrecision,FGCloudItem>::const_iterator CloudsIt = Clouds.begin();
 
     //set the iterator to the 'nr'th entry
     for (; nr > 0; nr--)
@@ -90,7 +127,196 @@ FGCloudItem FGPhysicalProperties::getCloudLayer(unsigned int nr) const
     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);
+}