Ref T773, use closest positions for average height/elevation values

Testing with XPlane:

* even in EDDF the field elevations vary from 353-368ft, which means a difference of 15ft or 4m
* that means it is important to use the closest values

src/blackcore/airspacemonitor.cpp

@@ -1423,10 +1423,11 @@ namespace BlackCore
                         bool fromNonMoving = false;
                         bool triedExtrapolation  = false;
                         bool couldNotExtrapolate = false;
+
                         CElevationPlane averagePlane = this->averageElevationOfOnGroundAircraft(situation, CElevationPlane::majorAirportRadius(), 2, 3);
                         if (averagePlane.isNull())
                         {
-                            averagePlane = this->averageElevationOfNonMovingAircraft(situation, CElevationPlane::majorAirportRadius(), 2);
+                            averagePlane = this->averageElevationOfNonMovingAircraft(situation, CElevationPlane::majorAirportRadius(), 2, 3);
                             fromNonMoving = true;
                         }
 

src/blackcore/context/contextnetworkimpl.cpp

@@ -1181,9 +1181,9 @@ namespace BlackCore
             return m_airspace->getLatestAirspaceAircraftSnapshot();
         }
 
-        CElevationPlane CContextNetwork::averageElevationOfNonMovingAircraft(const CAircraftSituation &reference, const CLength &range, int minValues) const
+        CElevationPlane CContextNetwork::averageElevationOfNonMovingAircraft(const CAircraftSituation &reference, const CLength &range, int minValues, int sufficientValues) const
         {
-            return m_airspace->averageElevationOfNonMovingAircraft(reference, range, minValues);
+            return m_airspace->averageElevationOfNonMovingAircraft(reference, range, minValues, sufficientValues);
         }
 
         void CContextNetwork::setClients(const CClientList &clients)

src/blackcore/context/contextnetworkimpl.h

@@ -119,7 +119,7 @@ namespace BlackCore
             virtual void rememberCGFromDB(const BlackMisc::PhysicalQuantities::CLength &cgFromDB, const BlackMisc::Aviation::CCallsign &callsign) override;
             virtual void rememberCGFromDB(const BlackMisc::PhysicalQuantities::CLength &cgFromDB, const QString &modelString) override;
             virtual BlackMisc::Simulation::CAirspaceAircraftSnapshot getLatestAirspaceAircraftSnapshot() const override;
-            virtual BlackMisc::Geo::CElevationPlane averageElevationOfNonMovingAircraft(const BlackMisc::Aviation::CAircraftSituation &reference, const BlackMisc::PhysicalQuantities::CLength &range, int minValues = 1) const override;
+            virtual BlackMisc::Geo::CElevationPlane averageElevationOfNonMovingAircraft(const BlackMisc::Aviation::CAircraftSituation &reference, const BlackMisc::PhysicalQuantities::CLength &range, int minValues = 1, int sufficientValues = 2) const override;
             virtual QList<QMetaObject::Connection> connectRemoteAircraftProviderSignals(
                 QObject *receiver,
                 std::function<void(const BlackMisc::Aviation::CAircraftSituation &)> addedSituationSlot,

src/blackmisc/aviation/aircraftsituationlist.cpp

@@ -611,25 +611,25 @@ namespace BlackMisc
             return c;
         }
 
-        CElevationPlane CAircraftSituationList::averageElevationOfTaxiingOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues) const
+        CElevationPlane CAircraftSituationList::averageElevationOfTaxiingOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues, int sufficientValues) const
         {
             if (this->size() < minValues) { return CElevationPlane::null(); } // no change to succeed
 
+            const CAircraftSituationList sorted = this->findWithGeodeticMSLHeight().findWithinRange(reference, range).sortedByEuclideanDistanceSquared(reference);
+            if (sorted.size() < minValues) { return CElevationPlane::null(); }
             QList<double> valuesInFt;
-            int count = 0;
             for (const CAircraftSituation &situation : *this)
             {
                 if (situation.getGroundElevationInfo() != CAircraftSituation::FromProvider) { continue; }
                 const bool canUse = !situation.isMoving() || (situation.isOnGroundFromNetwork() || situation.isOnGroundFromParts());
                 if (!canUse) { continue; }
-                if (!situation.isWithinRange(reference, range)) { continue; }
+
                 const double elvFt = situation.getGroundElevationPlane().getAltitude().value(CLengthUnit::ft());
                 valuesInFt.push_back(elvFt);
-                count++;
+                if (valuesInFt.size() >= sufficientValues) { break; }
-                if (count > 5 && valuesInFt.size() > 3 * minValues) { break; }
             }
 
-            if (count < minValues) { return CElevationPlane::null(); }
+            if (valuesInFt.size() < minValues) { return CElevationPlane::null(); }
 
             static const double MaxDevFt = CAircraftSituationChange::allowedAltitudeDeviation().value(CLengthUnit::ft());
             const QPair<double, double> elvStdDevMean = CMathUtils::standardDeviationAndMean(valuesInFt);

src/blackmisc/aviation/aircraftsituationlist.h

@@ -208,7 +208,7 @@ namespace BlackMisc
             int transferElevationForward(const PhysicalQuantities::CLength &radius = Geo::CElevationPlane::singlePointRadius());
 
             //! Average elevation for "nearby" aircraft "not/slowly moving" and having an elevation
-            Geo::CElevationPlane averageElevationOfTaxiingOnGroundAircraft(const CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1) const;
+            Geo::CElevationPlane averageElevationOfTaxiingOnGroundAircraft(const CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1, int sufficientValues = 2) const;
         };
 
         //! Situation per callsign

src/blackmisc/geo/coordinategeodeticlist.cpp

@@ -27,23 +27,23 @@ namespace BlackMisc
             CSequence<CCoordinateGeodetic>(other)
         { }
 
-        CElevationPlane CCoordinateGeodeticList::averageGeodeticHeight(const CCoordinateGeodetic &reference, const CLength &range, const CLength &maxDeviation, int minValues) const
+        CElevationPlane CCoordinateGeodeticList::averageGeodeticHeight(const CCoordinateGeodetic &reference, const CLength &range, const CLength &maxDeviation, int minValues, int sufficentValues) const
         {
             if (this->size() < minValues) { return CElevationPlane::null(); } // no change to succeed
 
             QList<double> valuesInFt;
-            int count = 0;
+            const CCoordinateGeodeticList sorted = this->findWithGeodeticMSLHeight().findWithinRange(reference, range).sortedByEuclideanDistanceSquared(reference);
-            for (const CCoordinateGeodetic &coordinate : *this)
+            if (sorted.size() < minValues) { return CElevationPlane::null(); }
+
+            // we know all values have MSL and are within range
+            for (const CCoordinateGeodetic &coordinate : sorted)
             {
-                if (!coordinate.hasMSLGeodeticHeight()) { continue; }
-                if (!coordinate.isWithinRange(reference, range)) { continue; }
                 const double elvFt = coordinate.geodeticHeight().value(CLengthUnit::ft());
                 valuesInFt.push_back(elvFt);
-                count++;
+                if (valuesInFt.size() >= sufficentValues) { break; }
-                if (count > 5 && valuesInFt.size() > 3 * minValues) { break; }
             }
 
-            if (count < minValues) { return CElevationPlane::null(); }
+            if (valuesInFt.size() < minValues) { return CElevationPlane::null(); }
 
             const double MaxDevFt = maxDeviation.value(CLengthUnit::ft());
             const QPair<double, double> elvStdDevMean = CMathUtils::standardDeviationAndMean(valuesInFt);

src/blackmisc/geo/coordinategeodeticlist.h

@@ -47,7 +47,7 @@ namespace BlackMisc
             CCoordinateGeodeticList(const CSequence<CCoordinateGeodetic> &other);
 
             //! Average height within range and having an height
-            CElevationPlane averageGeodeticHeight(const CCoordinateGeodetic &reference, const PhysicalQuantities::CLength &range, const PhysicalQuantities::CLength &maxDeviation = PhysicalQuantities::CLength(1.0, PhysicalQuantities::CLengthUnit::m()), int minValues = 3) const;
+            CElevationPlane averageGeodeticHeight(const CCoordinateGeodetic &reference, const PhysicalQuantities::CLength &range, const PhysicalQuantities::CLength &maxDeviation = PhysicalQuantities::CLength(1.0, PhysicalQuantities::CLengthUnit::m()), int minValues = 3, int sufficentValues = 5) const;
         };
     } //namespace
 } // namespace

src/blackmisc/simulation/remoteaircraftprovider.cpp

@@ -767,10 +767,10 @@ namespace BlackMisc
             return m_partsLastModified.value(callsign, -1);
         }
 
-        CElevationPlane CRemoteAircraftProvider::averageElevationOfNonMovingAircraft(const CAircraftSituation &reference, const CLength &range, int minValues) const
+        CElevationPlane CRemoteAircraftProvider::averageElevationOfNonMovingAircraft(const CAircraftSituation &reference, const CLength &range, int minValues, int sufficientValues) const
         {
             const CAircraftSituationList situations = this->latestOnGroundProviderElevations();
-            return situations.averageElevationOfTaxiingOnGroundAircraft(reference, range, minValues);
+            return situations.averageElevationOfTaxiingOnGroundAircraft(reference, range, minValues, sufficientValues);
         }
 
         bool CRemoteAircraftProvider::testAddAltitudeOffset(const CCallsign &callsign, const CLength &offset)

src/blackmisc/simulation/remoteaircraftprovider.h

@@ -251,7 +251,7 @@ namespace BlackMisc
             //! Average elevation of aircraft in given range, which are NOT moving
             //! \remark can be used to anticipate field elevation
             //! \threadsafe
-            virtual Geo::CElevationPlane averageElevationOfNonMovingAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1) const = 0;
+            virtual Geo::CElevationPlane averageElevationOfNonMovingAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1, int sufficientValues = 2) const = 0;
 
             //! Connect signals to slot receiver. As the interface is no QObject, slots can not be connected directly.
             //! In order to disconnect a list of connections is provided, which have to be disconnected manually.
@@ -344,7 +344,7 @@ namespace BlackMisc
             virtual int aircraftPartsAdded() const override;
             virtual qint64 situationsLastModified(const Aviation::CCallsign &callsign) const override;
             virtual qint64 partsLastModified(const Aviation::CCallsign &callsign) const override;
-            virtual Geo::CElevationPlane averageElevationOfNonMovingAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1) const override;
+            virtual Geo::CElevationPlane averageElevationOfNonMovingAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues = 1, int sufficientValues = 2) const override;
             virtual QList<QMetaObject::Connection> connectRemoteAircraftProviderSignals(
                 QObject *receiver,
                 std::function<void(const Aviation::CAircraftSituation &)> addedSituationSlot,

src/blackmisc/simulation/simulationenvironmentprovider.cpp

@@ -167,10 +167,10 @@ namespace BlackMisc
             return m_elvCoordinatesGnd;
         }
 
-        CElevationPlane ISimulationEnvironmentProvider::averageElevationOfOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues) const
+        CElevationPlane ISimulationEnvironmentProvider::averageElevationOfOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues, int sufficientValues) const
         {
             const CCoordinateGeodeticList coordinates = this->getElevationCoordinatesOnGround();
-            return coordinates.averageGeodeticHeight(reference, range, CAircraftSituationChange::allowedAltitudeDeviation(), minValues);
+            return coordinates.averageGeodeticHeight(reference, range, CAircraftSituationChange::allowedAltitudeDeviation(), minValues, sufficientValues);
         }
 
         CAltitude ISimulationEnvironmentProvider::highestElevation() const
@@ -592,10 +592,10 @@ namespace BlackMisc
             return this->provider()->findClosestElevationWithinRangeOrRequest(reference, range, callsign);
         }
 
-        CElevationPlane CSimulationEnvironmentAware::averageElevationOfOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues) const
+        CElevationPlane CSimulationEnvironmentAware::averageElevationOfOnGroundAircraft(const CAircraftSituation &reference, const CLength &range, int minValues, int sufficientValues) const
         {
             if (!this->hasProvider()) { return CElevationPlane::null(); }
-            return this->provider()->averageElevationOfOnGroundAircraft(reference, range, minValues);
+            return this->provider()->averageElevationOfOnGroundAircraft(reference, range, minValues, sufficientValues);
         }
 
         CAltitude CSimulationEnvironmentAware::highestElevation() const

src/blackmisc/simulation/simulationenvironmentprovider.h

@@ -44,7 +44,7 @@ namespace BlackMisc
 
             //! Average elevation of "on ground" cached values
             //! \threadsafe
-            Geo::CElevationPlane averageElevationOfOnGroundAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues) const;
+            Geo::CElevationPlane averageElevationOfOnGroundAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues, int sufficientValues) const;
 
             //! Highest elevation
             //! \threadsafe
@@ -298,7 +298,7 @@ namespace BlackMisc
             Geo::CElevationPlane findClosestElevationWithinRangeOrRequest(const Geo::ICoordinateGeodetic &reference, const PhysicalQuantities::CLength &range, const Aviation::CCallsign &callsign);
 
             //! \copydoc ISimulationEnvironmentProvider::averageElevationOfOnGroundAircraft
-            Geo::CElevationPlane averageElevationOfOnGroundAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues) const;
+            Geo::CElevationPlane averageElevationOfOnGroundAircraft(const Aviation::CAircraftSituation &reference, const PhysicalQuantities::CLength &range, int minValues, int sufficientValues) const;
 
             //! \copydoc ISimulationEnvironmentProvider::highestElevation
             Aviation::CAltitude highestElevation() const;