Updated Eci

CoordGeodetic.h

@@ -16,11 +16,21 @@ public:
     }
 
     /*
-     * radians
+     * default is in degrees 
      */
-    CoordGeodetic(double lat, double lon, double alt)
+    CoordGeodetic(double lat, double lon, double alt, bool radians = false)
-        : latitude(lat), longitude(lon), altitude(alt)
     {
+        if (radians)
+        {
+            latitude = lat;
+            longitude = lon;
+        }
+        else
+        {
+            latitude = DegreesToRadians(lat);
+            longitude = DegreesToRadians(lon);
+        }
+        altitude = alt;
     }
 
     CoordGeodetic(const CoordGeodetic& g)

Eci.cpp

@@ -1,26 +1,26 @@
 #include "Eci.h"
 
-#include "Globals.h"
+void Eci::ToEci(const Julian& date, const CoordGeodetic &g)
-
+{
-Eci::Eci(const Julian &date, const CoordGeodetic &geo)
+    /*
-: date_(date) {
+     * set date
+     */
+    date_ = date;
 
     static const double mfactor = kTWOPI * (kOMEGA_E / kSECONDS_PER_DAY);
-    const double latitude = geo.latitude;
-    const double longitude = geo.longitude;
-    const double altitude = geo.altitude;
 
     /*
      * Calculate Local Mean Sidereal Time for observers longitude
      */
-    const double theta = date_.ToLocalMeanSiderealTime(longitude);
+    const double theta = date_.ToLocalMeanSiderealTime(g.longitude);
 
     /*
      * take into account earth flattening
      */
-    const double c = 1.0 / sqrt(1.0 + kF * (kF - 2.0) * pow(sin(latitude), 2.0));
+    const double c = 1.0 /
+        sqrt(1.0 + kF * (kF - 2.0) * pow(sin(g.latitude), 2.0));
     const double s = pow(1.0 - kF, 2.0) * c;
-    const double achcp = (kXKMPER * c + altitude) * cos(latitude);
+    const double achcp = (kXKMPER * c + g.altitude) * cos(g.latitude);
 
     /*
      * X position in km
@@ -30,7 +30,7 @@ Eci::Eci(const Julian &date, const CoordGeodetic &geo)
      */
     position_.x = achcp * cos(theta);
     position_.y = achcp * sin(theta);
-    position_.z = (kXKMPER * s + altitude) * sin(latitude);
+    position_.z = (kXKMPER * s + g.altitude) * sin(g.latitude);
     position_.w = position_.GetMagnitude();
 
     /*
@@ -45,21 +45,8 @@ Eci::Eci(const Julian &date, const CoordGeodetic &geo)
     velocity_.w = velocity_.GetMagnitude();
 }
 
-Eci::Eci(const Julian &date, const Vector &position)
+CoordGeodetic Eci::ToGeodetic() const
-: date_(date), position_(position) {
+{
-
-}
-
-Eci::Eci(const Julian &date, const Vector &position, const Vector &velocity)
-: date_(date), position_(position), velocity_(velocity) {
-
-}
-
-Eci::~Eci(void) {
-}
-
-CoordGeodetic Eci::ToGeodetic() const {
-
     const double theta = AcTan(position_.y, position_.x);
 
     // 0 >= lon < 360
@@ -67,7 +54,9 @@ CoordGeodetic Eci::ToGeodetic() const {
     // 180 >= lon < 180
     const double lon = fmod(theta - date_.ToGreenwichSiderealTime(), kPI);
 
-    const double r = sqrt((position_.x * position_.x) + (position_.y * position_.y));
+    const double r = sqrt((position_.x * position_.x) + 
+            (position_.y * position_.y));
+    
     static const double e2 = kF * (2.0 - kF);
 
     double lat = AcTan(position_.z, r);
@@ -75,13 +64,15 @@ CoordGeodetic Eci::ToGeodetic() const {
     double c = 0.0;
     int cnt = 0;
 
-    do {
+    do
+    {
         phi = lat;
         const double sinphi = sin(phi);
         c = 1.0 / sqrt(1.0 - e2 * sinphi * sinphi);
         lat = AcTan(position_.z + kXKMPER * c * e2 * sinphi, r);
         cnt++;
-    } while (fabs(lat - phi) >= 1e-10 && cnt < 10);
+    }
+    while (fabs(lat - phi) >= 1e-10 && cnt < 10);
 
     const double alt = r / cos(lat) - kXKMPER * c;
 

Eci.h

@@ -4,31 +4,61 @@
 #include "CoordGeodetic.h"
 #include "Vector.h"
 #include "Julian.h"
+#include "Globals.h"
 
-class Eci {
+class Eci
+{
 public:
 
-    Eci() {
+    /*
-    };
+     * in degrees
-    Eci(const Julian &date, const CoordGeodetic &geo);
+     */
-    Eci(const Julian &date, const Vector &position);
+    Eci(const Julian& date, double latitude, double longitude, double altitude)
-    Eci(const Julian &date, const Vector &position, const Vector &velocity);
+    {
-    virtual ~Eci(void);
+        ToEci(date, CoordGeodetic(latitude, longitude, altitude));
+    }
 
-    Vector GetPosition() const {
+    Eci(const Julian& date, const CoordGeodetic& g)
+    {
+        ToEci(date, g);
+    }
+
+    Eci(const Julian &date, const Vector &position)
+        : date_(date), position_(position)
+    {
+    }
+
+    Eci(const Julian &date, const Vector &position, const Vector &velocity)
+        : date_(date), position_(position), velocity_(velocity)
+    {
+    }
+
+    virtual ~Eci()
+    {
+    }
+
+    Vector GetPosition() const
+    {
         return position_;
     }
 
-    Vector GetVelocity() const {
+    Vector GetVelocity() const
+    {
         return velocity_;
     }
 
-    Julian GetDate() const {
+    Julian GetDate() const
+    {
         return date_;
     }
 
     CoordGeodetic ToGeodetic() const;
 
+protected:
+    void ToEci(const Julian& date, double latitude, double longitude,
+            double altitude);
+    void ToEci(const Julian& date, const CoordGeodetic& g);
+
 private:
     Julian date_;
     Vector position_;

Observer.cpp

@@ -5,19 +5,15 @@
 /*
  * in degrees!
  */
-Observer::Observer(const double latitude, const double longitude, const double altitude) {
+Observer::Observer(const double latitude, const double longitude, const double altitude)
-
+    : geo_(DegreesToRadians(latitude), DegreesToRadians(longitude), altitude), 
-    geo_.latitude = DegreesToRadians(latitude);
+    observers_eci_(Julian(), geo_)
-    geo_.longitude = DegreesToRadians(longitude);
+{
-    geo_.altitude = altitude;
-
-    observers_eci_ = Eci(Julian(), geo_);
 }
 
 Observer::Observer(const CoordGeodetic &geo)
-: geo_(geo) {
+    : geo_(geo), observers_eci_(Julian(), geo_)
-
+{
-    observers_eci_ = Eci(Julian(), geo_);
 }
 
 Observer::~Observer(void) {

PassPredict.cpp

@@ -9,7 +9,6 @@ const int kPASS_TIME_STEP = 180; // time step in seconds, when searching for aos
 double FindMaxElevation(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian& aos, const Julian& los) {
 
     Observer obs(user_geo);
-    Eci eci;
 
     double max_elevation = -99.9;
     /*
@@ -31,7 +30,7 @@ double FindMaxElevation(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian&
         /*
          * find position
          */
-        sgp4.FindPosition(&eci, current_time);
+        Eci eci = sgp4.FindPosition(current_time);
         CoordTopographic topo = obs.GetLookAngle(eci);
 
         /*
@@ -85,7 +84,6 @@ double FindMaxElevation(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian&
 Julian FindCrossingPoint(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian& initial_time1, const Julian& initial_time2, bool finding_aos) {
 
     Observer obs(user_geo);
-    Eci eci;
 
     bool searching = true;
     unsigned int loop_count = 0;
@@ -100,7 +98,7 @@ Julian FindCrossingPoint(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian
         /*
          * find position
          */
-        sgp4.FindPosition(&eci, middle_time);
+        Eci eci = sgp4.FindPosition(middle_time);
         CoordTopographic topo = obs.GetLookAngle(eci);
 
         if (topo.elevation > 0.0) {
@@ -136,7 +134,6 @@ Julian FindCrossingPoint(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian
 void AOSLOS(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian& start_time, const Julian& end_time) {
 
     Observer obs(user_geo);
-    Eci eci;
 
     Timespan time_step(0, 0, 0, kPASS_TIME_STEP);
 
@@ -153,7 +150,7 @@ void AOSLOS(const CoordGeodetic& user_geo, SGP4& sgp4, const Julian& start_time,
     while (current_time < end_time) {
 
         // find position
-        sgp4.FindPosition(&eci, current_time);
+        Eci eci = sgp4.FindPosition(current_time);
         CoordTopographic topo = obs.GetLookAngle(eci);
 
         if (topo.elevation > 0.0) {

RunTest.cpp

@@ -23,7 +23,6 @@ void RunTle(Tle tle, double start, double end, double inc) {
     while (running) {
         try {
             double val;
-            Eci eci;
             if (first_run && current != 0.0) {
                 /*
                  * make sure first run is always as zero
@@ -35,7 +34,7 @@ void RunTle(Tle tle, double start, double end, double inc) {
                  */
                 val = current;
             }
-            model.FindPosition(&eci, val);
+            Eci eci = model.FindPosition(val);
 
             Vector position = eci.GetPosition();
             Vector velocity = eci.GetVelocity();

SGP4.cpp

@@ -178,22 +178,22 @@ void SGP4::Initialize() {
     first_run_ = false;
 }
 
-void SGP4::FindPosition(Eci* eci, double tsince) const {
+Eci SGP4::FindPosition(double tsince) const {
 
     if (use_deep_space_)
-        FindPositionSDP4(eci, tsince);
+        return FindPositionSDP4(tsince);
     else
-        FindPositionSGP4(eci, tsince);
+        return FindPositionSGP4(tsince);
 }
 
-void SGP4::FindPosition(Eci* eci, const Julian& date) const {
+Eci SGP4::FindPosition(const Julian& date) const {
 
     Timespan diff = date - elements_.Epoch();
 
-    FindPosition(eci, diff.GetTotalMinutes());
+    return FindPosition(diff.GetTotalMinutes());
 }
 
-void SGP4::FindPositionSDP4(Eci* eci, double tsince) const {
+Eci SGP4::FindPositionSDP4(double tsince) const {
 
     /*
      * the final values
@@ -286,7 +286,7 @@ void SGP4::FindPositionSDP4(Eci* eci, double tsince) const {
     /*
      * using calculated values, find position and velocity
      */
-    CalculateFinalPositionVelocity(eci, tsince, e,
+    return CalculateFinalPositionVelocity(tsince, e,
             a, omega, xl, xnode,
             xincl, perturbed_xlcof, perturbed_aycof,
             perturbed_x3thm1, perturbed_x1mth2, perturbed_x7thm1,
@@ -294,7 +294,7 @@ void SGP4::FindPositionSDP4(Eci* eci, double tsince) const {
 
 }
 
-void SGP4::FindPositionSGP4(Eci* eci, double tsince) const {
+Eci SGP4::FindPositionSGP4(double tsince) const {
 
     /*
      * the final values
@@ -363,7 +363,7 @@ void SGP4::FindPositionSGP4(Eci* eci, double tsince) const {
      * using calculated values, find position and velocity
      * we can pass in constants from Initialize() as these dont change
      */
-    CalculateFinalPositionVelocity(eci, tsince, e,
+    return CalculateFinalPositionVelocity(tsince, e,
             a, omega, xl, xnode,
             xincl, common_consts_.xlcof, common_consts_.aycof,
             common_consts_.x3thm1, common_consts_.x1mth2, common_consts_.x7thm1,
@@ -371,7 +371,7 @@ void SGP4::FindPositionSGP4(Eci* eci, double tsince) const {
 
 }
 
-void SGP4::CalculateFinalPositionVelocity(Eci* eci, const double& tsince, const double& e,
+Eci SGP4::CalculateFinalPositionVelocity(const double& tsince, const double& e,
         const double& a, const double& omega, const double& xl, const double& xnode,
         const double& xincl, const double& xlcof, const double& aycof,
         const double& x3thm1, const double& x1mth2, const double& x7thm1,
@@ -522,7 +522,9 @@ void SGP4::CalculateFinalPositionVelocity(Eci* eci, const double& tsince, const
     Julian julian(elements_.Epoch());
     julian.AddMin(tsince);
 
-    (*eci) = Eci(julian, position, velocity);
+    Eci eci(julian, position, velocity);
+
+    return eci;
 }
 
 static inline double EvaluateCubicPolynomial(const double x, const double constant,

SGP4.h

@@ -6,14 +6,15 @@
 #include "Eci.h"
 #include "SatelliteException.h"
 
-class SGP4 {
+class SGP4
+{
 public:
     SGP4(const Tle& tle);
     virtual ~SGP4(void);
 
     void SetTle(const Tle& tle);
-    void FindPosition(Eci* eci, double tsince) const;
+    Eci FindPosition(double tsince) const;
-    void FindPosition(Eci* eci, const Julian& date) const;
+    Eci FindPosition(const Julian& date) const;
 
     struct CommonConstants {
 
@@ -196,9 +197,9 @@ private:
             double* omgasm, double* xnodes, double* xll) const;
     void DeepSpaceSecular(const double& t, double* xll, double* omgasm,
             double* xnodes, double* em, double* xinc, double* xn) const;
-    void FindPositionSDP4(Eci* eci, double tsince) const;
+    Eci FindPositionSDP4(double tsince) const;
-    void FindPositionSGP4(Eci* eci, double tsince) const;
+    Eci FindPositionSGP4(double tsince) const;
-    void CalculateFinalPositionVelocity(Eci* eci, const double& tsince, const double& e,
+    Eci CalculateFinalPositionVelocity(const double& tsince, const double& e,
             const double& a, const double& omega, const double& xl, const double& xnode,
             const double& xincl, const double& xlcof, const double& aycof,
             const double& x3thm1, const double& x1mth2, const double& x7thm1,

SatTrack.cpp

@@ -10,11 +10,10 @@ int main() {
     "1 25544U 98067A   11146.36888985  .00025753  00000-0  16912-3 0  4201",
     "2 25544  51.6504 272.6534 0003891 329.5510  71.2188 15.75539412717473");
   SGP4 sgp4(tle);
-  Eci eci;
 
   while(1) {
     Julian now;
-    sgp4.FindPosition(&eci, now);
+    Eci eci = sgp4.FindPosition(now);
     CoordTopographic topo = obs.GetLookAngle(eci);
     CoordGeodetic geo = eci.ToGeodetic();
     std::cout << now << " ";