Enable setting of mobility precision and add test

model/leo-circular-orbit-mobility-model.cc

@@ -19,6 +19,7 @@ LeoCircularOrbitMobilityModel::GetTypeId ()
   static TypeId tid = TypeId ("ns3::LeoCircularOrbitMobilityModel")
     .SetParent<MobilityModel> ()
     .SetGroupName ("Leo")
+    .AddConstructor<LeoCircularOrbitMobilityModel> ()
     .AddAttribute ("Altitude",
                    "A height from the earth's surface in meters",
                    DoubleValue (1000.0),
@@ -32,11 +33,16 @@ LeoCircularOrbitMobilityModel::GetTypeId ()
                    MakeDoubleAccessor (&LeoCircularOrbitMobilityModel::SetInclination,
                    		       &LeoCircularOrbitMobilityModel::GetInclination),
                    MakeDoubleChecker<double> ())
+    .AddAttribute ("Precision",
+                   "The time precision with which to compute position updates. 0 means arbitrary precision",
+                   TimeValue (Seconds (1)),
+                   MakeTimeAccessor (&LeoCircularOrbitMobilityModel::m_precision),
+                   MakeTimeChecker ())
     ;
   return tid;
 }
 
-LeoCircularOrbitMobilityModel::LeoCircularOrbitMobilityModel() : MobilityModel (), m_latitude (0.0), m_offset (0.0)
+LeoCircularOrbitMobilityModel::LeoCircularOrbitMobilityModel() : MobilityModel (), m_latitude (0.0), m_offset (0.0), m_position ()
 {
   NS_LOG_FUNCTION_NOARGS ();
 }
@@ -107,13 +113,39 @@ LeoCircularOrbitMobilityModel::RotatePlane (double a, const Vector3D &x) const
 }
 
 Vector
-LeoCircularOrbitMobilityModel::DoGetPosition (void) const
+LeoCircularOrbitMobilityModel::CalcPosition (Time t) const
 {
   Vector3D x = Product (m_orbitHeight, Vector3D (cos (m_inclination) * cos (m_latitude),
   			       cos (m_inclination) * sin (m_latitude),
   			       sin (m_inclination)));
 
-  return RotatePlane (GetProgress (Simulator::Now ()), x);
+  return RotatePlane (GetProgress (t), x);
+}
+
+Vector LeoCircularOrbitMobilityModel::Update ()
+{
+  m_plane = PlaneNorm ();
+
+  m_position = CalcPosition (Simulator::Now ());
+  NotifyCourseChange ();
+
+  if (m_precision > Seconds (0))
+    {
+      Simulator::Schedule (m_precision, &LeoCircularOrbitMobilityModel::Update, this);
+    }
+
+  return m_position;
+}
+
+Vector
+LeoCircularOrbitMobilityModel::DoGetPosition (void) const
+{
+  if (m_precision == Time (0))
+    {
+      // Notice: NotifyCourseChange () will not be called
+      return CalcPosition (Simulator::Now ());
+    }
+  return m_position;
 }
 
 void
@@ -125,7 +157,7 @@ LeoCircularOrbitMobilityModel::DoSetPosition (const Vector &position)
   // SetPostion
   m_latitude = position.x;
   m_offset = position.y;
-  m_plane = PlaneNorm ();
+  Update ();
 }
 
 double LeoCircularOrbitMobilityModel::GetAltitude () const
@@ -136,7 +168,7 @@ double LeoCircularOrbitMobilityModel::GetAltitude () const
 void LeoCircularOrbitMobilityModel::SetAltitude (double h)
 {
   m_orbitHeight = LEO_EARTH_RAD_M + h;
-  m_plane = PlaneNorm ();
+  Update ();
 }
 
 double LeoCircularOrbitMobilityModel::GetInclination () const
@@ -148,7 +180,7 @@ void LeoCircularOrbitMobilityModel::SetInclination (double incl)
 {
   NS_ASSERT_MSG (incl != 0.0, "Plane must not be orthogonal to axis");
   m_inclination = (incl / 180) * M_PI;
-  m_plane = PlaneNorm ();
+  Update ();
 }
 
 };

model/leo-circular-orbit-mobility-model.h

@@ -70,6 +70,16 @@ private:
    */
   Vector3D m_plane;
 
+  /**
+   * Current position
+   */
+  Vector3D m_position;
+
+  /**
+   * Time precision for positions
+   */
+  Time m_precision;
+
   /**
    * \return the current position.
    */
@@ -94,6 +104,15 @@ private:
    * Advances a satellite by a degrees on the orbital plane
    */
   Vector3D RotatePlane (double a, const Vector3D &x) const;
+
+  /**
+   * Calculate the position at time
+   *
+   * \param t time
+   */
+  Vector CalcPosition (Time t) const;
+
+  Vector Update ();
 };
 
 }

model/leo-circular-orbit-position-allocator.cc

@@ -1,5 +1,7 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 
+#include "math.h"
+
 #include "ns3/integer.h"
 #include "leo-circular-orbit-position-allocator.h"
 
@@ -25,12 +27,12 @@ LeoCircularOrbitAllocator::GetTypeId (void)
                    "The number of orbits",
                    IntegerValue (1),
                    MakeIntegerAccessor (&LeoCircularOrbitAllocator::m_numOrbits),
-                   MakeIntegerChecker<uint64_t> ())
+                   MakeIntegerChecker<uint16_t> ())
     .AddAttribute ("NumSatellites",
                    "The number of satellites per orbit",
                    IntegerValue (1),
                    MakeIntegerAccessor (&LeoCircularOrbitAllocator::m_numSatellites),
-                   MakeIntegerChecker<uint64_t> ())
+                   MakeIntegerChecker<uint16_t> ())
   ;
   return tid;
 }
@@ -44,9 +46,17 @@ LeoCircularOrbitAllocator::AssignStreams (int64_t stream)
 Vector
 LeoCircularOrbitAllocator::GetNext () const
 {
-  return Vector (180 * ((double) m_lastOrbit / (double) m_numOrbits),
-	  	 360.0 * ((double) m_lastSatellite / (double) m_numSatellites),
+  Vector next = Vector (M_PI * (m_lastOrbit / (double) m_numOrbits),
+	  	 2 * M_PI * (m_lastSatellite / (double) m_numSatellites),
 	  	 0);
+
+  m_lastSatellite = (m_lastSatellite + 1) % m_numSatellites;
+  if (m_lastSatellite >= m_numSatellites)
+    {
+      m_lastOrbit = (m_lastOrbit + 1) % m_numOrbits;
+    }
+
+  return next;
 }
 
 };