+static FGPositioned::Type
+mapRobinTypeToFGPType(int aTy)
+{
+ switch (aTy) {
+ // case 1:
+ case 2: return FGPositioned::NDB;
+ case 3: return FGPositioned::VOR;
+ case 4: return FGPositioned::LOC;
+ case 5: return FGPositioned::ILS;
+ case 6: return FGPositioned::GS;
+ case 12:
+ case 13: return FGPositioned::DME;
+ case 99: return FGPositioned::INVALID; // end-of-file code
+ default:
+ throw sg_range_exception("Got a nav.dat type we don't recognize", "FGNavRecord::createFromStream");
+ }
+}
+
+static FGNavRecord* createNavFromStream(std::istream& aStream)
+{
+ int rawType;
+ aStream >> rawType;
+ if (aStream.eof() || (rawType == 99)) {
+ return NULL; // happens with, eg, carrier_nav.dat
+ }
+
+ double lat, lon, elev_ft, multiuse;
+ int freq, range;
+ std::string name, ident;
+ aStream >> lat >> lon >> elev_ft >> freq >> range >> multiuse >> ident;
+ getline(aStream, name);
+
+ SGGeod pos(SGGeod::fromDegFt(lon, lat, elev_ft));
+ name = simgear::strutils::strip(name);
+
+ if ((rawType >= 7) && (rawType <= 9)) {
+ // marker beacons use a different run-time class now
+ FGMarkerBeaconRecord::create(rawType, name, pos);
+ return NULL; // not a nav-record, but that's okay
+ }
+
+ FGPositioned::Type type = mapRobinTypeToFGPType(rawType);
+ if (type == FGPositioned::INVALID) {
+ return NULL;
+ }
+
+ // silently multiply adf frequencies by 100 so that adf
+ // vs. nav/loc frequency lookups can use the same code.
+ if (type == FGPositioned::NDB) {
+ freq *= 100;
+ }
+
+ return new FGNavRecord(type, ident, name, pos,
+ freq, range, multiuse);
+}