Cherry pick some GNSS improvements

app/position/positionkit.cpp

@@ -212,6 +212,13 @@ void PositionKit::parsePositionUpdate( const GeoPosition &newPosition )
     hasAnythingChanged = true;
   }
 
+  if ( !qgsDoubleNear( newPosition.elevation_diff, mPosition.elevation_diff ) )
+  {
+    mPosition.elevation_diff = newPosition.elevation_diff;
+    emit geoidSeparationChanged( mPosition.elevation_diff );
+    hasAnythingChanged = true;
+  }
+
   if ( newPosition.hasValidPosition() != mHasPosition )
   {
     mHasPosition = newPosition.hasValidPosition();
@@ -349,6 +356,11 @@ double PositionKit::altitude() const
   return mPosition.elevation;
 }
 
+double PositionKit::geoidSeparation() const
+{
+  return mPosition.elevation_diff;
+}
+
 QgsPoint PositionKit::positionCoordinate() const
 {
   if ( mPosition.hasValidPosition() )

app/position/positionkit.h

@@ -30,7 +30,9 @@ class PositionKit : public QObject
 
     Q_PROPERTY( double latitude READ latitude NOTIFY latitudeChanged )
     Q_PROPERTY( double longitude READ longitude NOTIFY longitudeChanged )
+
     Q_PROPERTY( double altitude READ altitude NOTIFY altitudeChanged )
+    Q_PROPERTY( double geoidSeparation READ geoidSeparation NOTIFY geoidSeparationChanged )
 
     // auxiliary property providing QgsPoint for lat/long/alt instead of separate properties
     Q_PROPERTY( QgsPoint positionCoordinate READ positionCoordinate NOTIFY positionCoordinateChanged )
@@ -84,6 +86,7 @@ class PositionKit : public QObject
     double latitude() const;
     double longitude() const;
     double altitude() const;
+    double geoidSeparation() const;
     QgsPoint positionCoordinate() const;
     bool hasPosition() const;
 
@@ -127,6 +130,7 @@ class PositionKit : public QObject
     void latitudeChanged( double );
     void longitudeChanged( double );
     void altitudeChanged( double );
+    void geoidSeparationChanged( double );
     void positionCoordinateChanged( QgsPoint );
     void hasPositionChanged( bool );
 

app/qml/gps/MMGpsDataDrawer.qml

@@ -316,6 +316,21 @@ MMComponents.MMDrawer {
 
             alignmentRight: Positioner.index % 2 === 1
           }
+
+          MMGpsComponents.MMGpsDataText {
+            width: parent.width / 2
+
+            title: qsTr( "Geoid separation" )
+            value: {
+              if ( !__positionKit.hasPosition || Number.isNaN( __positionKit.geoidSeparation ) ) {
+                return qsTr( "N/A" )
+              }
+              __inputUtils.formatNumber( __positionKit.geoidSeparation, 2 ) + " m"
+            }
+            visible: __positionKit.positionProvider && __positionKit.positionProvider.type() === "external"
+
+            alignmentRight: Positioner.index % 2 === 1
+          }
         }
       }
 

app/variablesmanager.cpp

@@ -72,6 +72,7 @@ QgsExpressionContextScope *VariablesManager::positionScope()
   addPositionVariable( scope, QStringLiteral( "longitude" ), position.longitude );
   addPositionVariable( scope, QStringLiteral( "latitude" ), position.latitude );
   addPositionVariable( scope, QStringLiteral( "altitude" ), position.elevation );
+  addPositionVariable( scope, QStringLiteral( "geoid_separation" ), position.elevation_diff );
   addPositionVariable( scope, QStringLiteral( "horizontal_accuracy" ), getGeoPositionAttribute( position.hacc ) );
   addPositionVariable( scope, QStringLiteral( "vertical_accuracy" ), getGeoPositionAttribute( position.vacc ) );
   addPositionVariable( scope, QStringLiteral( "ground_speed" ), getGeoPositionAttribute( position.speed ) );

vcpkg/ports/qtpositioning/android15_altitude_fix.patch

@@ -0,0 +1,68 @@
+diff --git a/src/plugins/position/android/jar/src/org/qtproject/qt/android/positioning/QtPositioning.java b/src/plugins/position/android/jar/src/org/qtproject/qt/android/positioning/QtPositioning.java
+index e4163b09..afb2889e 100644
+--- a/src/plugins/position/android/jar/src/org/qtproject/qt/android/positioning/QtPositioning.java
++++ b/src/plugins/position/android/jar/src/org/qtproject/qt/android/positioning/QtPositioning.java
+@@ -112,6 +112,8 @@ class QtPositioning implements LocationListener
+     static private void addMslAltitude(Location location)
+     {
+         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
++            if (location.hasMslAltitude()) // Nothing to be done
++                return;
+             if (altitudeConverter == null)
+                 altitudeConverter = new AltitudeConverter();
+             try {
+diff --git a/src/plugins/position/android/src/jnipositioning.cpp b/src/plugins/position/android/src/jnipositioning.cpp
+index 2b2919fa..0abc2cad 100644
+--- a/src/plugins/position/android/src/jnipositioning.cpp
++++ b/src/plugins/position/android/src/jnipositioning.cpp
+@@ -220,7 +220,7 @@ namespace AndroidPositioning {
+         return ret;
+     }
+
+-    QGeoPositionInfo positionInfoFromJavaLocation(const jobject &location)
++    QGeoPositionInfo positionInfoFromJavaLocation(const jobject &location, bool useAltConverter)
+     {
+         QGeoPositionInfo info;
+
+@@ -241,8 +241,11 @@ namespace AndroidPositioning {
+                 coordinate.setAltitude(value);
+         }
+         // MSL altitude, available in API Level 34+.
+-        // It will be available only if we requested it when starting updates.
+-        if (QNativeInterface::QAndroidApplication::sdkVersion() >= 34) {
++        // In API Level 34 it was available only if we manually added it.
++        // In API Level 35 (and potentially later), it's automatically added
++        // to the location object, so we need to use it *only* when the user
++        // set the relevant plugin parameter.
++        if (useAltConverter && QNativeInterface::QAndroidApplication::sdkVersion() >= 34) {
+             attributeExists = jniObject.callMethod<jboolean>("hasMslAltitude");
+             if (attributeExists) {
+                 const jdouble value = jniObject.callMethod<jdouble>("getMslAltitudeMeters");
+@@ -451,7 +454,7 @@ namespace AndroidPositioning {
+         if (location == nullptr)
+             return QGeoPositionInfo();
+
+-        const QGeoPositionInfo info = positionInfoFromJavaLocation(location);
++        const QGeoPositionInfo info = positionInfoFromJavaLocation(location, useAltitudeConverter);
+
+         return info;
+     }
+@@ -615,7 +618,6 @@ static void positionUpdated(JNIEnv *env, jobject thiz, QtJniTypes::Location loca
+ {
+     Q_UNUSED(env);
+     Q_UNUSED(thiz);
+-    QGeoPositionInfo info = AndroidPositioning::positionInfoFromJavaLocation(location.object());
+
+     QGeoPositionInfoSourceAndroid *source = AndroidPositioning::idToPosSource()->value(androidClassKey);
+     if (!source) {
+@@ -623,6 +625,10 @@ static void positionUpdated(JNIEnv *env, jobject thiz, QtJniTypes::Location loca
+         return;
+     }
+
++    const bool useAltitudeConverter = source->useAltitudeConverter();
++    QGeoPositionInfo info =
++            AndroidPositioning::positionInfoFromJavaLocation(location.object(), useAltitudeConverter);
++
+     //we need to invoke indirectly as the Looper thread is likely to be not the same thread
+     if (!isSingleUpdate)
+         QMetaObject::invokeMethod(source, "processPositionUpdate", Qt::AutoConnection,

vcpkg/ports/qtpositioning/portfile.cmake

@@ -3,7 +3,8 @@ include("${SCRIPT_PATH}/qt_install_submodule.cmake")
 
 set(${PORT}_PATCHES
     devendor-poly2tri.patch
-    foregroundservice.patch)
+    foregroundservice.patch
+    android15_altitude_fix.patch)
 
 vcpkg_check_features(OUT_FEATURE_OPTIONS FEATURE_OPTIONS
 FEATURES