Fixes #17574 Add Z support in AddCircularString map tools

python/gui/qgsmaptoolcapture.sip.in

@@ -102,6 +102,19 @@ convenient method to clean members
 
     int fetchLayerPoint( const QgsPointLocator::Match &match, QgsPoint &layerPoint );
 
+    QgsPoint pointFromPointXY( const QgsPointXY &point ) const;
+%Docstring
+ Creates a QgsPoint with ZM support if necessary (according to the
+ WkbType of the current layer) from a QgsPointXY.
+
+ \param point A QgsPointXY to convert
+
+ :return: a point if ZM support if necessary
+
+.. versionadded:: 3.0
+ :rtype: QgsPoint
+%End
+
     int addVertex( const QgsPointXY &point );
 
     int addVertex( const QgsPointXY &mapPoint, const QgsPointLocator::Match &match );

src/app/qgsmaptoolcircularstringcurvepoint.cpp

@@ -29,7 +29,7 @@ QgsMapToolCircularStringCurvePoint::QgsMapToolCircularStringCurvePoint( QgsMapTo
 
 void QgsMapToolCircularStringCurvePoint::cadCanvasReleaseEvent( QgsMapMouseEvent *e )
 {
-  QgsPoint mapPoint( e->mapPoint() );
+  QgsPoint mapPoint = pointFromPointXY( e->mapPoint() );
 
   if ( e->button() == Qt::LeftButton )
   {

src/app/qgsmaptoolcircularstringradius.cpp

@@ -43,7 +43,7 @@ void QgsMapToolCircularStringRadius::deactivate()
 
 void QgsMapToolCircularStringRadius::cadCanvasReleaseEvent( QgsMapMouseEvent *e )
 {
-  QgsPoint mapPoint( e->mapPoint() );
+  QgsPoint mapPoint = pointFromPointXY( e->mapPoint() );
 
   if ( e->button() == Qt::LeftButton )
   {
@@ -55,7 +55,7 @@ void QgsMapToolCircularStringRadius::cadCanvasReleaseEvent( QgsMapMouseEvent *e
     {
       if ( mPoints.size() % 2 )
       {
-        mTemporaryEndPoint = mapPoint;
+        mTemporaryEndPoint = pointFromPointXY( mapPoint );
 
         //initial radius is distance( tempPoint - mPoints.last ) / 2.0
         double minRadius = std::sqrt( QgsGeometryUtils::sqrDistance2D( mPoints.last(), mTemporaryEndPoint ) ) / 2.0;
@@ -136,7 +136,7 @@ void QgsMapToolCircularStringRadius::recalculateTempRubberBand( const QgsPointXY
   else
   {
     rubberBandPoints.append( mPoints.last() );
-    rubberBandPoints.append( QgsPoint( mousePosition ) );
+    rubberBandPoints.append( pointFromPointXY( mousePosition ) );
   }
   QgsCircularString *cString = new QgsCircularString();
   cString->setPoints( rubberBandPoints );

src/core/geometry/qgsgeometryutils.cpp

@@ -604,6 +604,24 @@ bool QgsGeometryUtils::segmentMidPoint( const QgsPoint &p1, const QgsPoint &p2,
   }
 
   result = possibleMidPoints.at( minDistIndex );
+
+  // add z support if necessary
+  if ( p1.is3D() && p2.is3D() )
+  {
+    result.convertTo( p1.wkbType() );
+    result.setZ( ( p1.z() + p2.z() ) / 2. );
+  }
+  else if ( p1.is3D() && !p2.is3D() )
+  {
+    result.convertTo( p1.wkbType() );
+    result.setZ( p1.z() );
+  }
+  else if ( !p1.is3D() && p2.is3D() )
+  {
+    result.convertTo( p2.wkbType() );
+    result.setZ( p2.z() );
+  }
+
   return true;
 }
 

src/gui/qgsmaptoolcapture.cpp

@@ -768,3 +768,48 @@ void QgsMapToolCapture::setPoints( const QVector<QgsPointXY> &pointList )
     mSnappingMatches.append( QgsPointLocator::Match() );
 }
 
+QgsPoint QgsMapToolCapture::pointFromPointXY( const QgsPointXY &point ) const
+{
+  QgsPoint newPoint( QgsWkbTypes::Point, point.x(), point.y() );
+
+  // get current layer
+  QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer *>( mCanvas->currentLayer() );
+  if ( !vlayer )
+  {
+    return newPoint;
+  }
+
+  // convert to the corresponding type for a full ZM support
+  QgsWkbTypes::Type type = vlayer->wkbType();
+  if ( QgsWkbTypes::hasZ( type ) && !QgsWkbTypes::hasM( type ) )
+  {
+    newPoint.convertTo( QgsWkbTypes::PointZ );
+  }
+  else if ( !QgsWkbTypes::hasZ( type ) && QgsWkbTypes::hasM( type ) )
+  {
+    newPoint.convertTo( QgsWkbTypes::PointM );
+  }
+  else if ( QgsWkbTypes::hasZ( type ) && QgsWkbTypes::hasM( type ) )
+  {
+    newPoint.convertTo( QgsWkbTypes::PointZM );
+  }
+
+  // set default value for Z if necessary
+  if ( QgsWkbTypes::hasZ( newPoint.wkbType() ) )
+    newPoint.setZ( defaultZValue() );
+
+  return newPoint;
+}
+
+#ifdef Q_OS_WIN
+bool QgsMapToolCapture::eventFilter( QObject *obj, QEvent *event )
+{
+  if ( event->type() != QEvent::ContextMenu )
+    return false;
+
+  if ( --mSkipNextContextMenuEvent == 0 )
+    obj->removeEventFilter( this );
+
+  return mSkipNextContextMenuEvent >= 0;
+}
+#endif

src/gui/qgsmaptoolcapture.h

@@ -147,6 +147,18 @@ class GUI_EXPORT QgsMapToolCapture : public QgsMapToolAdvancedDigitizing
     // TODO QGIS 3.0 returns an enum instead of a magic constant
     int fetchLayerPoint( const QgsPointLocator::Match &match, QgsPoint &layerPoint );
 
+    /**
+     * Creates a QgsPoint with ZM support if necessary (according to the
+     * WkbType of the current layer) from a QgsPointXY.
+     *
+     * \param point A QgsPointXY to convert
+     *
+     * \returns a point if ZM support if necessary
+     *
+     * \since QGIS 3.0
+     */
+    QgsPoint pointFromPointXY( const QgsPointXY &point ) const;
+
     /**
      * Adds a point to the rubber band (in map coordinates) and to the capture list (in layer coordinates)
      * \returns 0 in case of success, 1 if current layer is not a vector layer, 2 if coordinate transformation failed