NavData API additions

src/Airports/airport.hxx

@@ -52,6 +52,9 @@ class FGAirport : public FGPositioned
             const std::string& name, bool has_metar, Type aType);
     ~FGAirport();
 
+    static bool isType(FGPositioned::Type ty)
+    { return (ty >= FGPositioned::AIRPORT) && (ty <= FGPositioned::SEAPORT); }
+
     const std::string& getId() const { return ident(); }
     const std::string& getName() const { return _name; }
     std::string toString() const { return "an airport " + ident(); }

src/Airports/groundnetwork.cxx

@@ -451,6 +451,18 @@ FGParkingRef FGGroundNetwork::getParkingByIndex(unsigned int index) const
     return FGParkingRef(static_cast<FGParking*>(tn.ptr()));
 }
 
+FGParkingRef FGGroundNetwork::findParkingByName(const string &name) const
+{
+    auto it = std::find_if(m_parkings.begin(), m_parkings.end(), [name](const FGParkingRef& p) {
+       return p->ident() == name;
+    });
+
+    if (it == m_parkings.end())
+        return nullptr;
+
+    return *it;
+}
+
 void FGGroundNetwork::addSegment(const FGTaxiNodeRef &from, const FGTaxiNodeRef &to)
 {
     FGTaxiSegment* seg = new FGTaxiSegment(from, to);

src/Airports/groundnetwork.hxx

@@ -259,6 +259,8 @@ public:
 
     FGParkingRef getParkingByIndex(unsigned int index) const;
 
+    FGParkingRef findParkingByName(const std::string& name) const;
+
     /**
      * Find the taxiway segment joining two (ground-net) nodes. Returns
      * NULL if no such segment exists.

src/Airports/parking.hxx

@@ -49,6 +49,9 @@ private:
 
   SG_DISABLE_COPY(FGParking);
 public:
+  static bool isType(FGPositioned::Type ty)
+  { return (ty == FGPositioned::PARKING); }
+
   FGParking(int index,
             const SGGeod& pos,
             double heading, double radius,

src/Airports/runways.hxx

@@ -38,7 +38,9 @@ class FGRunway : public FGRunwayBase
   double _stopway;
   PositionedID _ils;
 public:
-  
+  static bool isType(FGPositioned::Type ty)
+  { return (ty ==  FGPositioned::RUNWAY); }
+
   FGRunway(PositionedID aGuid,
            PositionedID aAirport, const std::string& rwy_no,
             const SGGeod& aGeod,
@@ -126,6 +128,9 @@ public:
 class FGHelipad : public FGRunwayBase
 {
 public:
+    static bool isType(FGPositioned::Type ty)
+    { return (ty ==  FGPositioned::HELIPAD); }
+
     FGHelipad(PositionedID aGuid,
            PositionedID aAirport, const std::string& rwy_no,
             const SGGeod& aGeod,

src/Navaids/NavDataCache.cxx

@@ -1713,7 +1713,7 @@ void NavDataCache::abortTransaction()
 
 FGPositionedRef NavDataCache::loadById(PositionedID rowid)
 {
-  if (rowid == 0) {
+  if (rowid < 1) {
     return NULL;
   }
   if (!d) return NULL;

src/Navaids/navrecord.cxx

@@ -110,7 +110,12 @@ bool FGNavRecord::isVORTAC() const
 
 void FGNavRecord::setColocatedDME(PositionedID other)
 {
-  mColocated = other;
+    mColocated = other;
+}
+
+PositionedID FGNavRecord::colocatedDME() const
+{
+    return mColocated;
 }
 
 void FGNavRecord::updateFromXML(const SGGeod& geod, double heading)

src/Navaids/navrecord.hxx

@@ -56,6 +56,9 @@ class FGNavRecord : public FGPositioned
     mutable bool serviceable;   // for failure modeling
 
   public:
+    static bool isType(FGPositioned::Type ty)
+    { return (ty >= FGPositioned::NDB) && (ty <= FGPositioned::DME); }
+
     FGNavRecord( PositionedID aGuid,
                  Type type,
                  const std::string& ident,
@@ -98,8 +101,11 @@ class FGNavRecord : public FGPositioned
     void unbindFromNode(SGPropertyNode* nd) const;
 
     void setColocatedDME(PositionedID other);
+    
     bool hasDME() const;
 
+    PositionedID colocatedDME() const;
+
     bool isVORTAC() const;
 
     void updateFromXML(const SGGeod& geod, double heading);

src/Navaids/positioned.hxx

@@ -302,4 +302,26 @@ private:
   const SGVec3d mCart;
 };
 
+template <class T>
+T* fgpositioned_cast(FGPositioned* p)
+{
+    if (T::isType(p->type())) {
+        return static_cast<T*>(p);
+    }
+
+    return nullptr;
+}
+
+template <class T>
+T* fgpositioned_cast(FGPositionedRef p)
+{
+    if (!p) return nullptr;
+
+    if (T::isType(p->type())) {
+        return static_cast<T*>(p.ptr());
+    }
+
+    return nullptr;
+}
+
 #endif // of FG_POSITIONED_HXX