James Turner:

Modifications to support querying navaid database by station ID (not just
frequency.)  Some corresponding changes to testnavs.cxx to test new
functionality.

src/Navaids/navlist.cxx

@@ -1,4 +1,4 @@
-// navaids.cxx -- navaids management class
+// navlist.cxx -- navaids management class
 //
 // Written by Curtis Olson, started April 2000.
 //
@@ -72,9 +72,9 @@ bool FGNavList::init( SGPath path ) {
     while ( ! in.eof() ) {
 #endif
 
-        FGNav n;
+        FGNav *n = new FGNav;
-        in >> n;
+        in >> (*n);
-        if ( n.get_type() == '[' ) {
+        if ( n->get_type() == '[' ) {
             break;
         }
 
@@ -86,7 +86,9 @@ bool FGNavList::init( SGPath path ) {
 	cout << " freq = " << n.get_freq() << endl;
  	cout << " range = " << n.get_range() << endl << endl; */
 
-        navaids[n.get_freq()].push_back(n);
+        navaids      [n->get_freq() ].push_back(n);
+        ident_navaids[n->get_ident()].push_back(n);
+		
         in >> skipcomment;
 
 	/* if ( n.get_type() != 'N' ) {
@@ -116,25 +118,49 @@ bool FGNavList::query( double lon, double lat, double elev, double freq,
     nav_list_iterator current = stations.begin();
     nav_list_iterator last = stations.end();
 
-    // double az1, az2, s;
     Point3D aircraft = sgGeodToCart( Point3D(lon, lat, elev) );
+    return findNavFromList(aircraft, current, last, n);
+}
+
+
+bool FGNavList::findByIdent(const char* ident, double lon, double lat,
+                            FGNav *nav)
+{
+    nav_list_type stations = ident_navaids[ident];
+
+    nav_list_iterator current = stations.begin();
+    nav_list_iterator last = stations.end();
+	
+    Point3D aircraft = sgGeodToCart( Point3D(lon, lat, 0.0) );
+    return findNavFromList(aircraft, current, last, nav);
+}
+
+
+bool FGNavList::findNavFromList(const Point3D &aircraft, 
+                                nav_list_iterator current,
+                                nav_list_iterator end, FGNav *n)
+{
+    // double az1, az2, s;
+    
     Point3D station;
     double d;
-    for ( ; current != last ; ++current ) {
+    for ( ; current != end ; ++current ) {
 	// cout << "testing " << current->get_ident() << endl;
-	station = Point3D(current->get_x(), current->get_y(), current->get_z());
+	station = Point3D((*current)->get_x(), (*current)->get_y(),
+                          (*current)->get_z());
 
 	d = aircraft.distance3Dsquared( station );
 
 	// cout << "  dist = " << sqrt(d)
-	//      << "  range = " << current->get_range() * SG_NM_TO_METER << endl;
+	//      << "  range = " << current->get_range() * SG_NM_TO_METER
+        //      << endl;
 
-	// match up to twice the published range so we can model
+	// match up to 2 * range^2 the published range so we can model
 	// reduced signal strength
-	if ( d < (2 * current->get_range() * SG_NM_TO_METER 
+	double twiceRange = 2 * (*current)->get_range() * SG_NM_TO_METER;
-		  * 2 * current->get_range() * SG_NM_TO_METER ) ) {
+	if ( d < (twiceRange * twiceRange)) {
 	    // cout << "matched = " << current->get_ident() << endl;
-	    *n = *current;
+	    *n = (**current);
 	    return true;
 	}
     }

src/Navaids/navlist.hxx

@@ -30,27 +30,37 @@
 
 #include <map>
 #include <vector>
+#include STL_STRING
 
 #include "nav.hxx"
 
 SG_USING_STD(map);
 SG_USING_STD(vector);
-
+SG_USING_STD(string);
 
 class FGNavList {
 
     // convenience types
-    typedef vector < FGNav > nav_list_type;
+    typedef vector < FGNav* > nav_list_type;
     typedef nav_list_type::iterator nav_list_iterator;
     typedef nav_list_type::const_iterator nav_list_const_iterator;
 
-    // typedef map < int, nav_list_type, less<int> > nav_map_type;
     typedef map < int, nav_list_type > nav_map_type;
     typedef nav_map_type::iterator nav_map_iterator;
     typedef nav_map_type::const_iterator nav_map_const_iterator;
 
+    typedef map < string, nav_list_type > nav_ident_map_type;
+	
     nav_map_type navaids;
-
+    nav_ident_map_type ident_navaids;
+	
+    // internal helper to pick a Nav item from a nav_list based on
+    // distance from the aircraft point
+    bool findNavFromList(const Point3D &aircraft, 
+                         nav_list_iterator current,
+                         nav_list_iterator last,
+                         FGNav *n);
+	
 public:
 
     FGNavList();
@@ -62,6 +72,9 @@ public:
     // query the database for the specified frequency, lon and lat are
     // in degrees, elev is in meters
     bool query( double lon, double lat, double elev, double freq, FGNav *n );
+
+    // locate closest item in the DB matching the requested ident
+    bool findByIdent(const char* ident, double lon, double lat, FGNav *nav);
 };
 
 

src/Navaids/testnavs.cxx

@@ -3,13 +3,19 @@
 #include "fixlist.hxx"
 #include "ilslist.hxx"
 #include "navlist.hxx"
+#include "mkrbeacons.hxx"
+
+// change this!
+const string FG_DATA_DIR("/usr/local/lib/FlightGear");
 
 int main() {
     double heading, dist;
 
     current_navlist = new FGNavList;
-    SGPath p_nav( "/home/curt/FlightGear/Navaids/default.nav" );
+    SGPath p_nav( FG_DATA_DIR + "/Navaids/default.nav" );
+
     current_navlist->init( p_nav );
+	
     FGNav n;
     if ( current_navlist->query( -93.2 * SG_DEGREES_TO_RADIANS,
                                  45.14 * SG_DEGREES_TO_RADIANS,
@@ -21,8 +27,24 @@ int main() {
 	cout << "not picking up vor. :-(" << endl;
     }
 
+    FGNav dcs;
+    if (current_navlist->findByIdent("DCS", -3.3 * SG_DEGREES_TO_RADIANS,
+                                     55.9 * SG_DEGREES_TO_RADIANS, &dcs)) {
+						
+        cout << "Found DCS by ident" << endl;
+        if (dcs.get_freq() != 11520)
+            cout << "Frequency for DCS VOR is wrong (should be 115.20), it's " 
+                 << dcs.get_freq() << endl;
+    } else {
+        cout << "couldn't locate DCS (Dean-Cross) VOR" << endl;
+    }
+	
+    // we have to init the marker beacon storage before we parse the ILS file
+    current_beacons = new FGMarkerBeacons;
+    current_beacons->init();
+	
     current_ilslist = new FGILSList;
-    SGPath p_ils( "/home/curt/FlightGear/Navaids/default.ils" );
+    SGPath p_ils( FG_DATA_DIR + "/Navaids/default.ils" );
     current_ilslist->init( p_ils );
     FGILS i;
     if ( current_ilslist->query( -93.1 * SG_DEGREES_TO_RADIANS,
@@ -37,16 +59,21 @@ int main() {
     }
 
     current_fixlist = new FGFixList;
-    SGPath p_fix( "/home/curt/FlightGear/Navaids/default.fix" );
+    SGPath p_fix( FG_DATA_DIR + "/Navaids/default.fix" );
     current_fixlist->init( p_fix );
     FGFix fix;
-    if ( current_fixlist->query( "SHELL", -82 * SG_DEGREES_TO_RADIANS,
+	
-                                 41 * SG_DEGREES_TO_RADIANS, 3000,
+    // attempting to get the position relative to the OTR VOR; heading
+    // should be 108 degrees, distance 74nm (according to my SimCharts
+    // v1.5)
+    if ( current_fixlist->query( "DOGGA", -0.103 * SG_DEGREES_TO_RADIANS,
+                                 53.698 * SG_DEGREES_TO_RADIANS, 3000,
 				 &fix, &heading, &dist) )
     {
 	cout << "Found a matching fix" << endl;
 	cout << " id = " << fix.get_ident() << endl;
-	cout << " heading = " << heading << " dist = " << dist << endl;
+	cout << " heading = " << heading << " dist = " << dist * SG_METER_TO_NM
+             << endl;
     } else {
 	cout << "did not find fix. :-(" << endl;
     }