GNSS enhancements bundle (#4234)

* Geoid separation support for external providers (#4176)

* Recalculate ellipsoid elevation to orthometric (#4210)

* Enhance position altitude processing

Add EGM96_15 geoid model, which recalculates ellipsoid altitudes
returned by position providers. Expose this information in GPS
information panel.

* Fix broken builds

* Fix formatting

* Add geoid info for iOS

* Refactor PositionKit to singleton from context property

* Patch ios internal positioning provider

Provider returns now WGS84 ellipsoidal height on iOS

* Fix elevation transform & android workaround

Create new 3D transform utils function. Fix coordinate order passing.
Rework android 15+ Qt positioning workaround to VCPKG patch.

* Clean up & format code

* Add patch TODO

* Fix some review issues

* Refactor code to use existing QgsCoordinateTransformContext (#4228)

* Geoid separation support for internal providers (#4216)

* Squashed commit of the following:

commit 27b19a4
Author: Matej Bagar <matej.bagar@lutraconsulting.co.uk>
Date:   Mon Nov 24 15:22:46 2025 +0200

    Add mock location detection for android position provider

* Change default value for elevation_diff

* Custom geoid support (#4238)

* Fixed plural translation forms (#4183)

* Fixed android build to sync projects (#4243)

* Refactor support for orthometric heights on iOS

* Subtract antenna height from altitude

* Fix formatting & vcpkg bug

* Fix ios patch

* Fix ios patch v2

* Fix iOS error & constness

* Fix iOS error v3

* Add ellipsoidal elevation expr variable

* Change elevation calculation

* Increase click area for elevation info button

* Use default transform for internal providers

* Use default geoid model for android fused provider

* Add vertical CRS transform pass through for mock providers

* Add vertical CRS transfrom pass through for bluetooth provider

* Change android fused provider to default on android

* Fix GPS panel geoid model name info

* Change behaviour for internal provider on desktops

* Use EGM96 geoid model for simulated provider

* Fix iOS build

* Small refactor

* Set internal providers to use mixture of vertical CRS

* Fix review issues

* Refactor providers to use PositionTransformer

* Add PositionTransform reload on project load

* Add unit tests for PositionTransformer

* Rename project setting name

* Remove commented code, minor typo fixes, simulated provider cleanup

* Fix tests & formatting

* Fix tests

* Add test debug logs for CI

* Fix wrong test initialization for bluetoothless devices

* Revert "Fix wrong test initialization for bluetoothless devices"

This reverts commit 1541538.

* Refactor PositionTransformer creation & clear QgsProject refs in PositionKit

* Remove InputCoordinateTransformer

* Fix review issues

* Fix function typo

---------

Co-authored-by: Tomas Mizera <tomas.mizera@lutraconsulting.co.uk>
Co-authored-by: Kaustuv Pokharel <85729205+kaustuvpokharel@users.noreply.github.com>
Co-authored-by: Gabriel Bolbotina <80618569+gabriel-bolbotina@users.noreply.github.com>

Author: 4 people

CMakeLists.txt

@@ -389,6 +389,9 @@ 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
+)
 
 message(STATUS "QGIS_QUICK_DATA_PATH set to ${QGIS_QUICK_DATA_PATH}")
 # ########################################################################################

app/CMakeLists.txt

@@ -21,7 +21,6 @@ set(MM_SRCS
     layer/layertreemodel.cpp
     layer/layertreemodelpixmapprovider.cpp
     layer/layertreesortfiltermodel.cpp
-    map/inputcoordinatetransformer.cpp
     map/inputmapcanvasmap.cpp
     map/inputmapsettings.cpp
     map/inputmaptransform.cpp
@@ -43,6 +42,7 @@ set(MM_SRCS
     position/mapposition.cpp
     position/positiondirection.cpp
     position/positionkit.cpp
+    position/positiontransformer.cpp
     activelayer.cpp
     activeproject.cpp
     androidutils.cpp
@@ -111,7 +111,6 @@ set(MM_HDRS
     layer/layertreemodel.h
     layer/layertreemodelpixmapprovider.h
     layer/layertreesortfiltermodel.h
-    map/inputcoordinatetransformer.h
     map/inputmapcanvasmap.h
     map/inputmapsettings.h
     map/inputmaptransform.h
@@ -133,6 +132,7 @@ set(MM_HDRS
     position/mapposition.h
     position/positiondirection.h
     position/positionkit.h
+    position/positiontransformer.h
     activelayer.h
     activeproject.h
     androidutils.h

app/assets/us_nga_egm96_15.tif

@@ -477,7 +477,7 @@ QString InputUtils::geometryLengthAsString( const QgsGeometry &geometry )
 {
   QgsDistanceArea distanceArea;
   distanceArea.setEllipsoid( QStringLiteral( "WGS84" ) );
-  distanceArea.setSourceCrs( QgsCoordinateReferenceSystem::fromEpsgId( 4326 ), QgsCoordinateTransformContext() );
+  distanceArea.setSourceCrs( PositionKit::positionCrs2D(), QgsProject::instance()->transformContext() );
 
   qreal length = distanceArea.measureLength( geometry );
 
@@ -875,37 +875,45 @@ QgsPoint InputUtils::transformPoint( const QgsCoordinateReferenceSystem &srcCrs,
                                      const QgsCoordinateReferenceSystem &destCrs,
                                      const QgsCoordinateTransformContext &context,
                                      const QgsPoint &srcPoint )
+{
+  bool dummyFallbackOperationHappened; //ignored
+  return transformPoint( srcCrs, destCrs, context, srcPoint, dummyFallbackOperationHappened );
+}
+
+QgsPoint InputUtils::transformPoint( const QgsCoordinateReferenceSystem &srcCrs,
+                                     const QgsCoordinateReferenceSystem &destCrs,
+                                     const QgsCoordinateTransformContext &context,
+                                     const QgsPoint &srcPoint, bool &fallbackOperationOccurred )
 {
   // we do not want to transform empty points,
   // 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() ) );
+        fallbackOperationOccurred = ct.fallbackOperationOccurred();
+        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 )
@@ -954,12 +962,11 @@ 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,
-                                     QgsCoordinateTransformContext(),
+                                     PositionKit::positionCrs2D(),
+                                     mapSettings->transformContext(),
                                      positionMapCrs
                                    );
 
@@ -1716,7 +1723,7 @@ qreal InputUtils::distanceBetweenGpsAndFeature( QgsPoint gpsPosition, const Feat
 
   // Transform gps position to map CRS
   QgsPointXY transformedPosition = transformPoint(
-                                     coordinateReferenceSystemFromEpsgId( 4326 ),
+                                     PositionKit::positionCrs3DEllipsoidHeight(),
                                      mapSettings->destinationCrs(),
                                      mapSettings->transformContext(),
                                      gpsPosition
@@ -1764,7 +1771,7 @@ qreal InputUtils::angleBetweenGpsAndFeature( QgsPoint gpsPoint, const FeatureLay
 
   // Transform gps position to map CRS
   QgsPointXY transformedPosition = transformPoint(
-                                     coordinateReferenceSystemFromEpsgId( 4326 ),
+                                     PositionKit::positionCrs3DEllipsoidHeight(),
                                      mapSettings->destinationCrs(),
                                      mapSettings->transformContext(),
                                      gpsPoint

app/inpututils.cpp

@@ -305,6 +305,14 @@ class InputUtils: public QObject
         const QgsCoordinateTransformContext &context,
         const QgsPoint &srcPoint );
 
+    /**
+     * Overload of transformPoint function, which also notifies the caller if PROJ fallback operation occurred
+     */
+    static QgsPoint transformPoint( const QgsCoordinateReferenceSystem &srcCrs,
+                                    const QgsCoordinateReferenceSystem &destCrs,
+                                    const QgsCoordinateTransformContext &context,
+                                    const QgsPoint &srcPoint, bool &fallbackOperationOccurred );
+
     /**
       * Transforms point between CRS and screen pixels
       * Return empty QgsPoint if the transformation could not be applied or srcPoint is empty

app/inpututils.h

@@ -80,7 +80,6 @@
 #include "attributeformproxymodel.h"
 #include "attributetabmodel.h"
 #include "attributetabproxymodel.h"
-#include "inputcoordinatetransformer.h"
 #include "identifykit.h"
 #include "featurelayerpair.h"
 
@@ -349,7 +348,6 @@ void initDeclarative()
   qmlRegisterType< InputMapCanvasMap >( "mm", 1, 0, "MapCanvasMap" );
   qmlRegisterType< InputMapSettings >( "mm", 1, 0, "MapSettings" );
   qmlRegisterType< InputMapTransform >( "mm", 1, 0, "MapTransform" );
-  qmlRegisterType< InputCoordinateTransformer >( "mm", 1, 0, "CoordinateTransformer" );
   qmlRegisterUncreatableType< AbstractPositionProvider >( "mm", 1, 0, "PositionProvider", "Must be instantiated via its construct method" );
 
   // map tools
@@ -544,18 +542,34 @@ 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( pk->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.
   QObject lambdaContext;
 
+  QObject::connect( &activeProject, &ActiveProject::projectReloaded, &lambdaContext, [&pk]( QgsProject * project )
+  {
+    // read and set new vertical CRS definition
+    bool crsExists = false;
+    const QString crsWktDef = project->readEntry( QStringLiteral( "Mergin" ), QStringLiteral( "TargetVerticalCRS" ), QString(), &crsExists );
+    const QgsCoordinateReferenceSystem crs = QgsCoordinateReferenceSystem::fromWkt( crsWktDef );
+    pk->setVerticalCrs( crs );
+
+    // read and set new elevation transformation behavior
+    bool valueRead = false;
+    const bool skipElevationTransformation = project->readBoolEntry( QStringLiteral( "Mergin" ), QStringLiteral( "SkipElevationTransformation" ), true, &valueRead );
+    pk->setSkipElevationTransformation( skipElevationTransformation );
+
+    pk->refreshPositionTransformer( project->transformContext() );
+  } );
+
   // the automatic sync request on cold start will fail on MerginApiStatus not being initialized yet, so we call it again
   // after server ping is done
   if ( activeProject.autosyncController() )
@@ -658,7 +672,7 @@ 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( &app, &QGuiApplication::applicationStateChanged, &activeProject, &ActiveProject::appStateChanged );
   QObject::connect( &pw, &ProjectWizard::projectCreated, &localProjectsManager, &LocalProjectsManager::addLocalProject );
   QObject::connect( &activeProject, &ActiveProject::projectReloaded, vm.get(), &VariablesManager::merginProjectChanged );
@@ -690,7 +704,7 @@ 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
@@ -733,7 +747,6 @@ 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 );