Geoid separation support for internal providers

app/position/providers/androidpositionprovider.cpp

@@ -53,16 +53,19 @@ void jniOnPositionUpdated( JNIEnv *env, jclass clazz, jint instanceId, jobject l
 
   if ( location.callMethod<jboolean>( "hasAltitude" ) )
   {
-    const jdouble value = location.callMethod<jdouble>( "getAltitude" );
-    if ( !qFuzzyIsNull( value ) )
+    const jdouble ellipsoidHeight = location.callMethod<jdouble>( "getAltitude" );
+    if ( !qFuzzyIsNull( ellipsoidHeight ) )
     {
       // transform the altitude from EPSG:4979 (WGS84 (EPSG:4326) + ellipsoidal height) to specified geoid model
       const QgsPoint geoidPosition = InputUtils::transformPoint(
                                        PositionKit::positionCrs3DEllipsoidHeight(),
                                        PositionKit::positionCrs3D(),
                                        QgsProject::instance()->transformContext(),
-      {longitude, latitude, value} );
+      {longitude, latitude, ellipsoidHeight} );
       pos.elevation = geoidPosition.z();
+
+      const double geoidSeparation = ellipsoidHeight - geoidPosition.z();
+      pos.elevation_diff = geoidSeparation;
     }
   }
 

app/position/providers/bluetoothpositionprovider.cpp

@@ -204,11 +204,23 @@ void BluetoothPositionProvider::positionUpdateReceived()
     // we know the connection is working because we just received data from the device
     setState( tr( "Connected" ), State::Connected );
 
-    QByteArray rawNmea = mSocket->readAll();
-    QString nmea( rawNmea );
-
-    QgsGpsInformation data = mNmeaParser.parseNmeaString( nmea );
-
-    emit positionChanged( GeoPosition::fromQgsGpsInformation( data ) );
+    const QByteArray rawNmea = mSocket->readAll();
+    const QString nmea( rawNmea );
+
+    const QgsGpsInformation data = mNmeaParser.parseNmeaString( nmea );
+    GeoPosition positionData = GeoPosition::fromQgsGpsInformation( data );
+
+    // The geoid models used in GNSS devices can be often times unreliable, thus we apply the transformations ourselves
+    // GNSS supplied orthometric elevation -> ellipsoid elevation -> orthometric elevation based on our model
+    const double ellipsoidElevation = positionData.elevation + positionData.elevation_diff;
+    const QgsPoint geoidPosition = InputUtils::transformPoint(
+                                     PositionKit::positionCrs3DEllipsoidHeight(),
+                                     PositionKit::positionCrs3D(),
+                                     QgsProject::instance()->transformContext(),
+    {positionData.longitude, positionData.latitude, ellipsoidElevation} );
+    positionData.elevation = geoidPosition.z();
+    positionData.elevation_diff = ellipsoidElevation - geoidPosition.z();
+
+    emit positionChanged( positionData );
   }
 }

app/position/providers/internalpositionprovider.cpp

@@ -153,6 +153,20 @@ void InternalPositionProvider::parsePositionUpdate( const QGeoPositionInfo &posi
     positionDataHasChanged = true;
   }
 
+  // QGeoCoordinate::altitude() docs claim that it is above the sea level (i.e. geoid) altitude,
+  // but that's not really true in our case:
+  // - on Android - it is MSL altitude only if "useMslAltitude" parameter is passed to the Android
+  //   Qt positioning plugin, which we don't do - see https://doc.qt.io/qt-6/position-plugin-android.html
+  // - on iOS - it would return MSL altitude, but we have a custom patch in vcpkg to return
+  //   ellipsoid altitude (so we do not rely on geoid model of unknown quality/resolution)
+  const double ellipsoidAltitude = position.coordinate().altitude();
+  const double geoidSeparation = ellipsoidAltitude - geoidPosition.z();
+  if ( !qgsDoubleNear( geoidSeparation, mLastPosition.elevation_diff ) )
+  {
+    mLastPosition.elevation_diff = geoidSeparation;
+    positionDataHasChanged = true;
+  }
+
   bool hasSpeedInfo = position.hasAttribute( QGeoPositionInfo::GroundSpeed );
   if ( hasSpeedInfo && !qgsDoubleNear( position.attribute( QGeoPositionInfo::GroundSpeed ), mLastPosition.speed ) )
   {

app/position/providers/simulatedpositionprovider.cpp

@@ -8,25 +8,30 @@
  ***************************************************************************/
 
 #include "simulatedpositionprovider.h"
+
+#include <memory>
+#include <QtNumeric>
+
+#include "inpututils.h"
 #include "qgspoint.h"
 
-SimulatedPositionProvider::SimulatedPositionProvider( double longitude, double latitude, double flightRadius, double timerTimeout, QObject *parent )
+SimulatedPositionProvider::SimulatedPositionProvider( const double longitude, const double latitude, const double flightRadius, const double updateTimeout, QObject *parent )
   : AbstractPositionProvider( QStringLiteral( "simulated" ), QStringLiteral( "internal" ), QStringLiteral( "Simulated provider" ), parent )
   , mTimer( new QTimer() )
   , mLongitude( longitude )
   , mLatitude( latitude )
   , mFlightRadius( flightRadius )
-  , mTimerTimeout( timerTimeout )
+  , mTimerTimeout( updateTimeout )
 {
   std::random_device seed;
-  mGenerator = std::unique_ptr<std::mt19937>( new std::mt19937( seed() ) );
+  mGenerator = std::make_unique<std::mt19937>( seed() );
 
   connect( mTimer.get(), &QTimer::timeout, this, &SimulatedPositionProvider::generateNextPosition );
 
   SimulatedPositionProvider::startUpdates();
 }
 
-void SimulatedPositionProvider::setUpdateInterval( double msecs )
+void SimulatedPositionProvider::setUpdateInterval( const double msecs )
 {
   stopUpdates();
   mTimerTimeout = msecs;
@@ -37,7 +42,7 @@ SimulatedPositionProvider::~SimulatedPositionProvider() = default;
 
 void SimulatedPositionProvider::startUpdates()
 {
-  mTimer->start( mTimerTimeout );
+  mTimer->start( static_cast<int>( mTimerTimeout ) );
   generateNextPosition();
 }
 
@@ -51,7 +56,7 @@ void SimulatedPositionProvider::closeProvider()
   mTimer->stop();
 }
 
-void SimulatedPositionProvider::setPosition( QgsPoint position )
+void SimulatedPositionProvider::setPosition( const QgsPoint position )
 {
   if ( position.isEmpty() )
     return;
@@ -84,16 +89,27 @@ void SimulatedPositionProvider::generateRadiusPosition()
   position.latitude = latitude;
   position.longitude = longitude;
 
-  double altitude = ( *mGenerator )() % 40 + 20; // rand altitude <20,55>m and lost (0)
-  if ( altitude <= 55 )
+  double ellipsoidAltitude = ( *mGenerator )() % 40 + 80; // rand altitude <80,115>m and lost (NaN)
+  if ( ellipsoidAltitude <= 115 )
+  {
+    const QgsPoint geoidPosition = InputUtils::transformPoint(
+                                     PositionKit::positionCrs3DEllipsoidHeight(),
+                                     PositionKit::positionCrs3D(),
+                                     QgsCoordinateTransformContext(),
+    {longitude, latitude, ellipsoidAltitude} );
+    position.elevation = geoidPosition.z();
+    position.elevation_diff = ellipsoidAltitude - position.elevation;
+  }
+  else
   {
-    position.elevation = altitude;
+    position.elevation = qQNaN();
+    position.elevation_diff = qQNaN();
   }
 
-  QDateTime timestamp = QDateTime::currentDateTime();
+  const QDateTime timestamp = QDateTime::currentDateTime();
   position.utcDateTime = timestamp;
 
-  position.direction = 360 - int( mAngle ) % 360;
+  position.direction = 360 - static_cast<int>( mAngle ) % 360;
 
   int accuracy = ( *mGenerator )() % 40; // rand accuracy <0,35>m and lost (-1)
   if ( accuracy > 35 )
@@ -115,9 +131,16 @@ void SimulatedPositionProvider::generateConstantPosition()
   GeoPosition position;
   position.latitude = mLatitude;
   position.longitude = mLongitude;
-  position.elevation = 20;
+  // we take 100 as elevation returned by WGS84 ellipsoid and recalculate it to geoid
+  const QgsPoint geoidPosition = InputUtils::transformPoint(
+                                   PositionKit::positionCrs3DEllipsoidHeight(),
+                                   PositionKit::positionCrs3D(),
+                                   QgsCoordinateTransformContext(),
+  {mLongitude, mLatitude, 100} );
+  position.elevation = geoidPosition.z();
+  position.elevation_diff = 100 - position.elevation;
   position.utcDateTime = QDateTime::currentDateTime();
-  position.direction = 360 - int( mAngle ) % 360;
+  position.direction = 360 - static_cast<int>( mAngle ) % 360;
   position.hacc = ( *mGenerator )() % 20;
   position.satellitesUsed = ( *mGenerator )() % 30;
   position.satellitesVisible = ( *mGenerator )() % 30;

app/position/providers/simulatedpositionprovider.h

@@ -39,16 +39,16 @@ class SimulatedPositionProvider : public AbstractPositionProvider
       double updateTimeout = 1000,
       QObject *parent = nullptr
     );
-    virtual ~SimulatedPositionProvider() override;
+    ~SimulatedPositionProvider() override;
 
-    virtual void setUpdateInterval( double msecs ) override;
+    void setUpdateInterval( double msecs ) override;
 
   public slots:
-    virtual void startUpdates() override;
-    virtual void stopUpdates() override;
-    virtual void closeProvider() override;
+    void startUpdates() override;
+    void stopUpdates() override;
+    void closeProvider() override;
 
-    virtual void setPosition( QgsPoint position ) override;
+    void setPosition( QgsPoint position ) override;
 
     void generateNextPosition();
 

app/qml/gps/MMGpsDataDrawer.qml

@@ -323,10 +323,10 @@ MMComponents.MMDrawer {
 
             title: qsTr( "Geoid separation" )
             value: {
-              if ( !__positionKit.hasPosition || Number.isNaN( __positionKit.geoidSeparation ) ) {
+              if ( !PositionKit.hasPosition || Number.isNaN( PositionKit.geoidSeparation ) ) {
                 return qsTr( "N/A" )
               }
-              __inputUtils.formatNumber( __positionKit.geoidSeparation, 2 ) + " m"
+              __inputUtils.formatNumber( PositionKit.geoidSeparation, 2 ) + " m"
             }
 
             alignmentRight: Positioner.index % 2 === 1

app/test/testposition.cpp

@@ -396,8 +396,7 @@ void TestPosition::testPositionTracking()
   QSignalSpy trackingSpy( &manager, &PositionTrackingManager::trackedGeometryChanged );
 
   trackingSpy.wait( 4000 ); // new position should be emited in 2k ms
-
-  QVERIFY( manager.trackedGeometry().asWkt( 3 ).startsWith( QStringLiteral( "LineString ZM (-92.36 38.93 20" ) ) );
+  QVERIFY( manager.trackedGeometry().asWkt( 3 ).startsWith( QStringLiteral( "LineString ZM (-92.36 38.93 133.331" ) ) );
 
   // store the geometry
   QgsVectorLayer *trackingLayer = QgsProject::instance()->mapLayer<QgsVectorLayer *>( "tracking_layer_aad89df7_21db_466e_b5c1_a80160f74c01" );
@@ -411,7 +410,7 @@ void TestPosition::testPositionTracking()
 
   int addedFid = addedSpy.at( 1 ).at( 0 ).toInt();
   QgsFeature f = trackingLayer->getFeature( addedFid );
-  QVERIFY( f.geometry().asWkt( 3 ).startsWith( QStringLiteral( "LineString ZM (-92.36 38.93 20" ) ) );
+  QVERIFY( f.geometry().asWkt( 3 ).startsWith( QStringLiteral( "LineString ZM (-92.36 38.93 133.331" ) ) );
 
   QString datetimeFormat = QStringLiteral( "dd.MM.yyyy hh:mm:ss" );
   QString dateTrackingStartedFromManager = manager.startTime().toString( datetimeFormat );