From 15139a42b6a064e66bff74958893dd748769d68c Mon Sep 17 00:00:00 2001
From: mfranz <mfranz>
Date: Fri, 5 Oct 2007 21:54:52 +0000
Subject: [PATCH] - make FGAirport::search() more versatile, so that it can't
only search the next airport or airport with METAR station, but about any
type of airport - as a side effect this change makes it also 30 to 50%
faster :-)
In the long run this linear search shall be replaced with a spatial
algorithm (like octree), which will be a much bigger performance gain.
---
src/Airports/simple.cxx | 38 ++++++++++++++++++----------
src/Airports/simple.hxx | 15 +++++++----
src/Environment/environment_ctrl.cxx | 7 +++--
src/Instrumentation/gps.cxx | 2 +-
src/Scripting/NasalSys.cxx | 4 +--
5 files changed, 42 insertions(+), 24 deletions(-)
diff --git a/src/Airports/simple.cxx b/src/Airports/simple.cxx
index 6efac4c0e..e92b08fbd 100644
--- a/src/Airports/simple.cxx
+++ b/src/Airports/simple.cxx
@@ -187,25 +187,35 @@ const FGAirport* FGAirportList::findFirstById( const string& id, bool exact )
// search for the airport nearest the specified position
-FGAirport* FGAirportList::search( double lon_deg, double lat_deg,
- bool with_metar )
+FGAirport* FGAirportList::search(double lon_deg, double lat_deg)
+{
+ static FGAirportSearchFilter accept_any;
+ return search(lon_deg, lat_deg, accept_any);
+}
+
+
+// search for the airport nearest the specified position and
+// passing the filter
+FGAirport* FGAirportList::search(double lon_deg, double lat_deg,
+ FGAirportSearchFilter& search)
{
- int closest = -1;
double min_dist = 360.0;
- unsigned int i;
- for ( i = 0; i < airports_array.size(); ++i ) {
+ airport_list_iterator it = airports_array.begin();
+ airport_list_iterator end = airports_array.end();
+ airport_list_iterator closest = end;
+ for (; it != end; ++it) {
+ if (!search.acceptable(*it))
+ continue;
+
// crude manhatten distance based on lat/lon difference
- double d = fabs(lon_deg - airports_array[i]->getLongitude())
- + fabs(lat_deg - airports_array[i]->getLatitude());
- if ( d < min_dist ) {
- if ( !with_metar || (with_metar&&airports_array[i]->getMetar()) ) {
- closest = i;
- min_dist = d;
- }
+ double d = fabs(lon_deg - (*it)->getLongitude())
+ + fabs(lat_deg - (*it)->getLatitude());
+ if (d < min_dist) {
+ closest = it;
+ min_dist = d;
}
}
-
- return ( closest > -1 ? airports_array[closest] : NULL );
+ return closest != end ? *closest : 0;
}
diff --git a/src/Airports/simple.hxx b/src/Airports/simple.hxx
index 9251ee423..d1930730a 100644
--- a/src/Airports/simple.hxx
+++ b/src/Airports/simple.hxx
@@ -106,6 +106,12 @@ private:
};
+class FGAirportSearchFilter {
+public:
+ virtual ~FGAirportSearchFilter() {}
+ virtual bool acceptable(FGAirport*) { return true; }
+};
+
typedef map < string, FGAirport* > airport_map;
typedef airport_map::iterator airport_map_iterator;
@@ -122,7 +128,6 @@ private:
airport_map airports_by_id;
airport_list airports_array;
- //set < string > ai_dirs;
public:
// Constructor (new)
@@ -150,10 +155,10 @@ public:
// search for the airport closest to the specified position
// (currently a linear inefficient search so it's probably not
- // best to use this at runtime.) If with_metar is true, then only
- // return station id's marked as having metar data.
- // Returns NULL if fails (unlikely unless none have metar and with_metar spec'd!)
- FGAirport* search( double lon_deg, double lat_deg, bool with_metar );
+ // best to use this at runtime.) An FGAirportSearchFilter class
+ // can be used to restrict the possible choices to a subtype.
+ FGAirport* search( double lon_deg, double lat_deg );
+ FGAirport* search( double lon_deg, double lat_deg, FGAirportSearchFilter& );
/**
* Return the number of airports in the list.
diff --git a/src/Environment/environment_ctrl.cxx b/src/Environment/environment_ctrl.cxx
index 82af0e027..5733ed67a 100644
--- a/src/Environment/environment_ctrl.cxx
+++ b/src/Environment/environment_ctrl.cxx
@@ -41,6 +41,9 @@
SG_USING_STD(sort);
+class metar_filter : public FGAirportSearchFilter {
+ virtual bool acceptable(FGAirport *a) { return a->getMetar(); }
+} metar_only;
////////////////////////////////////////////////////////////////////////
@@ -648,7 +651,7 @@ FGMetarEnvironmentCtrl::init ()
const FGAirport* a = globals->get_airports()
->search( longitude->getDoubleValue(),
latitude->getDoubleValue(),
- true );
+ metar_only );
if ( a ) {
FGMetarResult result = fetch_data( a->getId() );
if ( result.m != NULL ) {
@@ -711,7 +714,7 @@ FGMetarEnvironmentCtrl::update(double delta_time_sec)
const FGAirport* a = globals->get_airports()
->search( longitude->getDoubleValue(),
latitude->getDoubleValue(),
- true );
+ metar_only );
if ( a ) {
if ( !last_apt || last_apt->getId() != a->getId()
|| fetch_elapsed > same_station_interval_sec )
diff --git a/src/Instrumentation/gps.cxx b/src/Instrumentation/gps.cxx
index ae0f3c810..b466948c4 100644
--- a/src/Instrumentation/gps.cxx
+++ b/src/Instrumentation/gps.cxx
@@ -308,7 +308,7 @@ GPS::update (double delta_time_sec)
// If the get-nearest-airport-node is true.
// Get the nearest airport, and set it as waypoint 1.
if (_get_nearest_airport_node->getBoolValue()) {
- const FGAirport* a = globals->get_airports()->search(longitude_deg, latitude_deg, false);
+ const FGAirport* a = globals->get_airports()->search(longitude_deg, latitude_deg);
if(a) {
_wp1_ID_node->setStringValue(a->getId().c_str());
wp1_longitude_deg = a->getLongitude();
diff --git a/src/Scripting/NasalSys.cxx b/src/Scripting/NasalSys.cxx
index 32dcb98e6..423935d34 100644
--- a/src/Scripting/NasalSys.cxx
+++ b/src/Scripting/NasalSys.cxx
@@ -496,11 +496,11 @@ static naRef f_airportinfo(naContext c, naRef me, int argc, naRef* args)
FGAirportList *aptlst = globals->get_airports();
FGAirport *apt;
if(argc == 0)
- apt = aptlst->search(lon->getDoubleValue(), lat->getDoubleValue(), false);
+ apt = aptlst->search(lon->getDoubleValue(), lat->getDoubleValue());
else if(argc == 1 && naIsString(args[0]))
apt = aptlst->search(naStr_data(args[0]));
else if(argc == 2 && naIsNum(args[0]) && naIsNum(args[1]))
- apt = aptlst->search(args[1].num, args[0].num, false);
+ apt = aptlst->search(args[1].num, args[0].num);
else {
naRuntimeError(c, "airportinfo() with invalid function arguments");
return naNil();