Recalculate ellipsoid elevation to orthometric

CMakeLists.txt

@@ -402,6 +402,9 @@ file(
   PATTERN "*.cmake" EXCLUDE
   PATTERN "vcpkg*" EXCLUDE
 )
+file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/app/assets/us_nga_egm96_15.tif
+     DESTINATION ${ASSETS_DIR_PATH}/app/android/assets/qgis-data/proj
+)
 # ########################################################################################
 # SUBDIRECTORIES
 # ########################################################################################

app/inpututils.cpp

@@ -476,7 +476,7 @@ QString InputUtils::geometryLengthAsString( const QgsGeometry &geometry )
 {
   QgsDistanceArea distanceArea;
   distanceArea.setEllipsoid( QStringLiteral( "WGS84" ) );
-  distanceArea.setSourceCrs( QgsCoordinateReferenceSystem::fromEpsgId( 4326 ), QgsCoordinateTransformContext() );
+  distanceArea.setSourceCrs( PositionKit::positionCrs2D(), QgsCoordinateTransformContext() );
 
   qreal length = distanceArea.measureLength( geometry );
 
@@ -879,32 +879,30 @@ QgsPoint InputUtils::transformPoint( const QgsCoordinateReferenceSystem &srcCrs,
   // QGIS would convert them to a valid (0, 0) points
   if ( srcPoint.isEmpty() )
   {
-    return QgsPoint();
+    return {};
   }
 
   try
   {
-    QgsCoordinateTransform ct( srcCrs, destCrs, context );
+    const QgsCoordinateTransform ct( srcCrs, destCrs, context );
     if ( ct.isValid() )
     {
       if ( !ct.isShortCircuited() )
       {
-        const QgsPointXY transformed = ct.transform( srcPoint.x(), srcPoint.y() );
-        const QgsPoint pt( transformed.x(), transformed.y(), srcPoint.z(), srcPoint.m() );
+        const QgsVector3D transformed = ct.transform( QgsVector3D( srcPoint.x(), srcPoint.y(), srcPoint.z() ) );
+        const QgsPoint pt( transformed.x(), transformed.y(), transformed.z(), srcPoint.m() );
         return pt;
       }
-      else
-      {
-        return srcPoint;
-      }
+
+      return srcPoint;
     }
   }
   catch ( QgsCsException &cse )
   {
     Q_UNUSED( cse )
   }
 
-  return QgsPoint();
+  return {};
 }
 
 QPointF InputUtils::transformPointToScreenCoordinates( const QgsCoordinateReferenceSystem &srcCrs, InputMapSettings *mapSettings, const QgsPoint &srcPoint )
@@ -953,11 +951,10 @@ QgsPoint InputUtils::mapPointToGps( QPointF mapPosition, InputMapSettings *mapSe
     return QgsPoint();
 
   QgsPoint positionMapCrs = mapSettings->screenToCoordinate( mapPosition );
-  QgsCoordinateReferenceSystem crsGPS = coordinateReferenceSystemFromEpsgId( 4326 );
 
   const QgsPointXY transformedXY = transformPoint(
                                      mapSettings->destinationCrs(),
-                                     crsGPS,
+                                     PositionKit::positionCrs2D(),
                                      QgsCoordinateTransformContext(),
                                      positionMapCrs
                                    );
@@ -1715,7 +1712,7 @@ qreal InputUtils::distanceBetweenGpsAndFeature( QgsPoint gpsPosition, const Feat
 
   // Transform gps position to map CRS
   QgsPointXY transformedPosition = transformPoint(
-                                     coordinateReferenceSystemFromEpsgId( 4326 ),
+                                     PositionKit::positionCrs3D(),
                                      mapSettings->destinationCrs(),
                                      mapSettings->transformContext(),
                                      gpsPosition
@@ -1763,7 +1760,7 @@ qreal InputUtils::angleBetweenGpsAndFeature( QgsPoint gpsPoint, const FeatureLay
 
   // Transform gps position to map CRS
   QgsPointXY transformedPosition = transformPoint(
-                                     coordinateReferenceSystemFromEpsgId( 4326 ),
+                                     PositionKit::positionCrs3D(),
                                      mapSettings->destinationCrs(),
                                      mapSettings->transformContext(),
                                      gpsPoint

app/main.cpp

@@ -544,13 +544,13 @@ int main( int argc, char *argv[] )
   LayerDetailLegendImageProvider *layerDetailLegendImageProvider( new LayerDetailLegendImageProvider );
 
   // build position kit, save active provider to QSettings and load previously active provider
-  PositionKit pk;
-  QObject::connect( &pk, &PositionKit::positionProviderChanged, as, [as]( AbstractPositionProvider * provider )
+  PositionKit *pk = engine.singletonInstance<PositionKit *>( "MMInput", "PositionKit" );
+  QObject::connect( pk, &PositionKit::positionProviderChanged, as, [as]( AbstractPositionProvider * provider )
   {
     as->setActivePositionProviderId( provider ? provider->id() : QLatin1String() );
   } );
-  pk.setPositionProvider( pk.constructActiveProvider( as ) );
-  pk.setAppSettings( as );
+  pk->setPositionProvider( PositionKit::constructActiveProvider( as ) );
+  pk->setAppSettings( as );
 
   // Lambda context object can be used in all lambda functions defined here,
   // it secures lambdas, so that they are destroyed when this object is destroyed to avoid crashes.
@@ -648,7 +648,7 @@ int main( int argc, char *argv[] )
     notificationModel.addError( message );
   } );
   // Direct connections
-  QObject::connect( &app, &QGuiApplication::applicationStateChanged, &pk, &PositionKit::appStateChanged );
+  QObject::connect( &app, &QGuiApplication::applicationStateChanged, pk, &PositionKit::appStateChanged );
   QObject::connect( &pw, &ProjectWizard::projectCreated, &localProjectsManager, &LocalProjectsManager::addLocalProject );
   QObject::connect( &activeProject, &ActiveProject::projectReloaded, vm.get(), &VariablesManager::merginProjectChanged );
   QObject::connect( &activeProject, &ActiveProject::projectWillBeReloaded, &inputProjUtils, &InputProjUtils::resetHandlers );
@@ -679,7 +679,7 @@ int main( int argc, char *argv[] )
   if ( tests.testingRequested() )
   {
     tests.initTestDeclarative();
-    tests.init( ma.get(), &iu, vm.get(), &pk, as );
+    tests.init( ma.get(), &iu, vm.get(), pk, as );
     return tests.runTest();
   }
 #endif
@@ -722,7 +722,6 @@ int main( int argc, char *argv[] )
   engine.rootContext()->setContextProperty( "__projectWizard", &pw );
   engine.rootContext()->setContextProperty( "__localProjectsManager", &localProjectsManager );
   engine.rootContext()->setContextProperty( "__variablesManager", vm.get() );
-  engine.rootContext()->setContextProperty( "__positionKit", &pk );
 
   // add image provider to pass QIcons/QImages from C++ to QML
   engine.rootContext()->setContextProperty( "__layerTreeModelPixmapProvider", layerTreeModelPixmapProvider );

app/map/inputcoordinatetransformer.cpp

@@ -13,12 +13,14 @@
  */
 
 #include "inputcoordinatetransformer.h"
+
+#include "positionkit.h"
 #include "qgslogger.h"
 
 InputCoordinateTransformer::InputCoordinateTransformer( QObject *parent )
   : QObject( parent )
 {
-  mCoordinateTransform.setSourceCrs( QgsCoordinateReferenceSystem::fromEpsgId( 4326 ) );
+  mCoordinateTransform.setSourceCrs( PositionKit::positionCrs3D() );
 }
 
 QgsPoint InputCoordinateTransformer::projectedPosition() const

app/maptools/recordingmaptool.cpp

@@ -59,7 +59,7 @@ void RecordingMapTool::addPoint( const QgsPoint &point )
     pointToAdd = mPositionKit->positionCoordinate();
 
     QgsPoint transformed = InputUtils::transformPoint(
-                             PositionKit::positionCRS(),
+                             PositionKit::positionCrs3D(),
                              mActiveLayer->crs(),
                              mActiveLayer->transformContext(),
                              pointToAdd
@@ -594,7 +594,7 @@ void RecordingMapTool::onPositionChanged()
       QgsPoint position = mPositionKit->positionCoordinate();
 
       QgsPointXY transformed = InputUtils::transformPoint(
-                                 PositionKit::positionCRS(),
+                                 PositionKit::positionCrs3D(),
                                  mActiveLayer->sourceCrs(),
                                  mActiveLayer->transformContext(),
                                  position

app/position/mapposition.cpp

@@ -105,7 +105,7 @@ void MapPosition::recalculateMapPosition()
     {
       QgsPointXY srcPoint = QgsPointXY( geoposition.x(), geoposition.y() );
       QgsPointXY mapPositionXY = InputUtils::transformPointXY(
-                                   mPositionKit->positionCRS(),
+                                   mPositionKit->positionCrs3D(),
                                    mMapSettings->destinationCrs(),
                                    mMapSettings->transformContext(),
                                    srcPoint

app/position/positionkit.cpp

@@ -33,11 +33,21 @@ PositionKit::PositionKit( QObject *parent )
 {
 }
 
-QgsCoordinateReferenceSystem PositionKit::positionCRS()
+QgsCoordinateReferenceSystem PositionKit::positionCrs3D()
+{
+  return QgsCoordinateReferenceSystem::fromEpsgId( 9707 );
+}
+
+QgsCoordinateReferenceSystem PositionKit::positionCrs2D()
 {
   return QgsCoordinateReferenceSystem::fromEpsgId( 4326 );
 }
 
+QgsCoordinateReferenceSystem PositionKit::positionCrs3DEllipsoidHeight()
+{
+  return QgsCoordinateReferenceSystem::fromEpsgId( 4979 );
+}
+
 void PositionKit::startUpdates()
 {
   if ( mPositionProvider )

app/position/positionkit.h

@@ -15,6 +15,7 @@
 #include "qgspoint.h"
 #include "qgscoordinatereferencesystem.h"
 #include <QObject>
+#include <QtQml/qqmlregistration.h>
 
 class AppSettings;
 
@@ -27,6 +28,8 @@ class AppSettings;
 class PositionKit : public QObject
 {
     Q_OBJECT
+    QML_ELEMENT
+    QML_SINGLETON
 
     Q_PROPERTY( double latitude READ latitude NOTIFY latitudeChanged )
     Q_PROPERTY( double longitude READ longitude NOTIFY longitudeChanged )
@@ -112,8 +115,12 @@ class PositionKit : public QObject
     double vdop() const;
     double pdop() const;
 
-    // Coordinate reference system of position - WGS84 (constant)
-    Q_INVOKABLE static QgsCoordinateReferenceSystem positionCRS();
+    // Coordinate reference system - WGS84 (EPSG:4326)
+    static QgsCoordinateReferenceSystem positionCrs2D();
+    // Coordinate reference system - WGS84 + ellipsoid height (EPSG:4979)
+    static QgsCoordinateReferenceSystem positionCrs3DEllipsoidHeight();
+    // Coordinate reference system of position - WGS84 + geoid height - egm96_15 (EPSG:9707)
+    static QgsCoordinateReferenceSystem positionCrs3D();
 
     Q_INVOKABLE static AbstractPositionProvider *constructProvider( const QString &type, const QString &id, const QString &name = QString() );
     Q_INVOKABLE static AbstractPositionProvider *constructActiveProvider( AppSettings *appsettings );

app/position/providers/androidpositionprovider.cpp

@@ -19,6 +19,8 @@
 
 #include <QTimeZone>
 
+#include "inpututils.h"
+
 
 int AndroidPositionProvider::sLastInstanceId = 0;
 QMap<int, AndroidPositionProvider *> AndroidPositionProvider::sInstances;
@@ -53,14 +55,17 @@ void jniOnPositionUpdated( JNIEnv *env, jclass clazz, jint instanceId, jobject l
   {
     const jdouble value = location.callMethod<jdouble>( "getAltitude" );
     if ( !qFuzzyIsNull( value ) )
-      pos.elevation = value;
+    {
+      // transform the altitude from EPSG:4979 (WGS84 (EPSG:4326) + ellipsoidal height) to specified geoid model
+      const QgsPoint geoidPosition = InputUtils::transformPoint(
+                                       PositionKit::positionCrs3DEllipsoidHeight(),
+                                       PositionKit::positionCrs3D(),
+                                       QgsCoordinateTransformContext(),
+      {longitude, latitude, value} );
+      pos.elevation = geoidPosition.z();
+    }
   }
 
-  // TODO: we are getting ellipsoid elevation here. From API level 34 (Android 14),
-  // there is AltitudeConverter() class in Java that can be used to add MSL altitude
-  // to Location object. How to deal with this correctly? (we could also convert
-  // to MSL (orthometric) altitude ourselves if we add geoid model to our APK
-
   // horizontal accuracy
   if ( location.callMethod<jboolean>( "hasAccuracy" ) )
   {

app/position/providers/internalpositionprovider.cpp

@@ -9,6 +9,7 @@
 
 #include "internalpositionprovider.h"
 #include "coreutils.h"
+#include "inpututils.h"
 
 #include "qgis.h"
 
@@ -140,9 +141,15 @@ void InternalPositionProvider::parsePositionUpdate( const QGeoPositionInfo &posi
     positionDataHasChanged = true;
   }
 
-  if ( !qgsDoubleNear( position.coordinate().altitude(), mLastPosition.elevation ) )
+  // 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(),
+  {position.coordinate().longitude(), position.coordinate().latitude(), position.coordinate().altitude()} );
+  if ( !qgsDoubleNear( geoidPosition.z(), mLastPosition.elevation ) )
   {
-    mLastPosition.elevation = position.coordinate().altitude();
+    mLastPosition.elevation = geoidPosition.z();
     positionDataHasChanged = true;
   }
 

app/position/tracking/positiontrackingmanager.cpp

@@ -95,7 +95,7 @@ void PositionTrackingManager::commitTrackedPath()
   }
 
   // convert captured geometry to the destination layer's CRS
-  QgsGeometry geometryInLayerCRS = InputUtils::transformGeometry( mTrackedGeometry, QgsCoordinateReferenceSystem::fromEpsgId( 4326 ), trackingLayer );
+  QgsGeometry geometryInLayerCRS = InputUtils::transformGeometry( mTrackedGeometry, PositionKit::positionCrs3D(), trackingLayer );
 
   // create feature - add tracking variables to scope
   QgsExpressionContextScope *scope = new QgsExpressionContextScope( QStringLiteral( "MM_Tracking" ) );
@@ -332,7 +332,7 @@ void PositionTrackingManager::setVariablesManager( VariablesManager *newVariable
 
 QgsCoordinateReferenceSystem PositionTrackingManager::crs() const
 {
-  return QgsCoordinateReferenceSystem::fromEpsgId( 4326 );
+  return PositionKit::positionCrs3D();
 }
 
 void PositionTrackingManager::tryAgain()

app/qml/gps/MMBluetoothConnectionDrawer.qml

@@ -12,13 +12,14 @@ import QtQuick.Controls
 import QtQuick.Layouts
 
 import mm 1.0 as MM
+import MMInput
 
 import "../components" as MMComponents
 
 MMComponents.MMDrawer {
   id: root
 
-  property var positionProvider: __positionKit.positionProvider
+  property var positionProvider: PositionKit.positionProvider
   property string howToConnectGPSLink: __inputHelp.howToConnectGPSLink
 
   property string titleText: {
@@ -52,7 +53,7 @@ MMComponents.MMDrawer {
     }
     else if ( rootstate.state === "waitingToReconnect" )
     {
-      return __positionKit.positionProvider.stateMessage + "<br><br>" +
+      return PositionKit.positionProvider.stateMessage + "<br><br>" +
           qsTr( "You can close this message, we will try to repeatedly connect to your device." )
     }