Use QgsMapTool::messageEmitted() signal for tool messages

python/3d/auto_generated/qgs3dmapcanvas.sip.in

@@ -90,6 +90,24 @@ scene's clipping planes
 .. versionadded:: 4.0
 %End
 
+    bool crossSectionEnabled() const;
+%Docstring
+Returns ``True`` if the cross section mode is enabled or the 3d scene
+has other clipping planes applied
+
+.. seealso:: :py:func:`enableCrossSection`
+
+.. versionadded:: 4.0
+%End
+
+    void crossSectionEnabledChanged( bool enabled );
+%Docstring
+Emitted when the cross section mode is enabled or disabled
+
+.. seealso:: :py:func:`enableCrossSection`
+
+.. versionadded:: 4.0
+%End
 
   protected:
     virtual void showEvent( QShowEvent *e );

python/PyQt6/3d/auto_generated/qgs3dmapcanvas.sip.in

@@ -90,6 +90,24 @@ scene's clipping planes
 .. versionadded:: 4.0
 %End
 
+    bool crossSectionEnabled() const;
+%Docstring
+Returns ``True`` if the cross section mode is enabled or the 3d scene
+has other clipping planes applied
+
+.. seealso:: :py:func:`enableCrossSection`
+
+.. versionadded:: 4.0
+%End
+
+    void crossSectionEnabledChanged( bool enabled );
+%Docstring
+Emitted when the cross section mode is enabled or disabled
+
+.. seealso:: :py:func:`enableCrossSection`
+
+.. versionadded:: 4.0
+%End
 
   protected:
     virtual void showEvent( QShowEvent *e );

src/3d/qgs3dmapcanvas.cpp

@@ -190,6 +190,9 @@ QgsCameraController *Qgs3DMapCanvas::cameraController()
 
 void Qgs3DMapCanvas::enableCrossSection( const QgsPointXY &startPoint, const QgsPointXY &endPoint, double width, bool setSideView )
 {
+  if ( !mScene )
+    return;
+
   const QgsVector3D startVec { startPoint.x(), startPoint.y(), 0 };
   const QgsVector3D endVec { endPoint.x(), endPoint.y(), 0 };
   const QList<QVector4D> clippingPlanes = Qgs3DUtils::lineSegmentToClippingPlanes(
@@ -225,10 +228,18 @@ void Qgs3DMapCanvas::enableCrossSection( const QgsPointXY &startPoint, const Qgs
 
 void Qgs3DMapCanvas::disableCrossSection()
 {
+  if ( !mScene )
+    return;
+
   mScene->disableClipping();
   emit crossSectionEnabledChanged( false );
 }
 
+bool Qgs3DMapCanvas::crossSectionEnabled() const
+{
+  return mScene ? !mScene->clipPlaneEquations().isEmpty() : false;
+}
+
 void Qgs3DMapCanvas::resetView()
 {
   if ( !mScene )

src/3d/qgs3dmapcanvas.h

@@ -116,6 +116,14 @@ class _3D_EXPORT Qgs3DMapCanvas : public QWindow
      */
     void disableCrossSection();
 
+    /**
+     * Returns TRUE if the cross section mode is enabled or the 3d scene has other clipping planes applied
+     *
+     * \see enableCrossSection()
+     * \since QGIS 4.0
+     */
+    bool crossSectionEnabled() const;
+
 #ifndef SIP_RUN
 
     /**
@@ -217,9 +225,13 @@ class _3D_EXPORT Qgs3DMapCanvas : public QWindow
     //! Emitted when the camera navigation \a speed is changed.
     void cameraNavigationSpeedChanged( double speed );
 
-    //! Emitted when the cross section mode is enabled or disabled
-    void crossSectionEnabledChanged( bool enabled );
 #endif
+    /**
+     *  Emitted when the cross section mode is enabled or disabled
+     *  \see enableCrossSection()
+     *  \since QGIS 4.0
+     */
+    void crossSectionEnabledChanged( bool enabled );
 
   private slots:
     void captureDepthBuffer();

src/app/3d/qgs3dmapcanvaswidget.cpp

@@ -708,6 +708,7 @@ void Qgs3DMapCanvasWidget::setMapSettings( Qgs3DMapSettings *map )
 
   mMapToolClippingPlanes = std::make_unique<QgsMapToolClippingPlanes>( mMainCanvas, this );
   mMapToolClippingPlanes->setAction( mActionSetClippingPlanes );
+  connect( mMapToolClippingPlanes.get(), &QgsMapToolClippingPlanes::finishedSuccessfully, this, &Qgs3DMapCanvasWidget::onCrossSectionToolFinished );
 
   // none of the actions in the Camera menu are supported by globe yet, so just hide it completely
   mActionCamera->setVisible( map->sceneMode() == Qgis::SceneMode::Local );
@@ -1207,7 +1208,7 @@ void Qgs3DMapCanvasWidget::setClippingPlanesOn2DCanvas()
   mMessageBar->pushInfo( QString(), tr( "Select a rectangle using 3 points on the main 2D map view to define the cross-section of this 3D scene" ) );
 }
 
-void Qgs3DMapCanvasWidget::crossSectionToolFinished()
+void Qgs3DMapCanvasWidget::onCrossSectionToolFinished()
 {
   this->activateWindow();
   this->raise();

src/app/3d/qgs3dmapcanvaswidget.h

@@ -96,8 +96,6 @@ class APP_EXPORT Qgs3DMapCanvasWidget : public QWidget
 
     bool eventFilter( QObject *watched, QEvent *event ) override;
 
-    void crossSectionToolFinished();
-
   private slots:
     void resetView();
     void configure();
@@ -138,7 +136,8 @@ class APP_EXPORT Qgs3DMapCanvasWidget : public QWidget
     void onGpuMemoryLimitReached();
 
     void onPointCloudChangeAttributeSettingsChanged();
-    // void onPointCloudChangeAttributePointFilterChanged();
+
+    void onCrossSectionToolFinished();
 
   private:
     void updateCheckedActionsFromMapSettings( const Qgs3DMapSettings *mapSettings ) const;

src/app/3d/qgsmaptoolclippingplanes.cpp

@@ -23,7 +23,6 @@
 #include "qgspolygon.h"
 #include "qgs3dmapcanvaswidget.h"
 #include "qgs3dmapscene.h"
-#include "qgsmessagebar.h"
 #include "qgisapp.h"
 #include "qgscoordinatetransform.h"
 #include "qgsrubberband.h"
@@ -32,7 +31,7 @@
 
 
 QgsMapToolClippingPlanes::QgsMapToolClippingPlanes( QgsMapCanvas *canvas, Qgs3DMapCanvasWidget *mapCanvas )
-  : QgsMapTool( canvas ), m3DCanvas( mapCanvas )
+  : QgsMapTool( canvas ), m3DCanvasWidget( mapCanvas )
 {
   mRubberBandPolygon.reset( new QgsRubberBand( canvas, Qgis::GeometryType::Polygon ) );
   mRubberBandLines.reset( new QgsRubberBand( canvas, Qgis::GeometryType::Line ) );
@@ -54,7 +53,7 @@ void QgsMapToolClippingPlanes::activate()
   mRubberBandPolygon->show();
   mCt = std::make_unique<QgsCoordinateTransform>(
     mCanvas->mapSettings().destinationCrs(),
-    m3DCanvas->mapCanvas3D()->mapSettings()->crs(),
+    m3DCanvasWidget->mapCanvas3D()->mapSettings()->crs(),
     mCanvas->mapSettings().transformContext()
   );
 }
@@ -142,14 +141,13 @@ void QgsMapToolClippingPlanes::canvasReleaseEvent( QgsMapMouseEvent *e )
         QgsDebugError( QStringLiteral( "Could not reproject cross-section extent to 3d map canvas crs." ) );
       }
 
-      if ( !crossSectionPolygon.intersects( m3DCanvas->mapCanvas3D()->scene()->sceneExtent() ) )
+      if ( !crossSectionPolygon.intersects( m3DCanvasWidget->mapCanvas3D()->scene()->sceneExtent() ) )
       {
         clear();
-        QgsMessageBar *msgBar = QgisApp::instance()->messageBar();
         if ( crossSectionPolygon.isNull() )
-          msgBar->pushWarning( QString(), tr( "Could not reproject the cross-section extent to 3D map coordinates." ) );
+          emit messageEmitted( tr( "Could not reproject the cross-section extent to 3D map coordinates." ), Qgis::MessageLevel::Warning );
         else
-          msgBar->pushInfo( QString(), tr( "The cross section is outside of the scene extent, please select a new one!" ) );
+          emit messageEmitted( tr( "The cross section is outside of the scene extent, please select a new one!" ), Qgis::MessageLevel::Info );
       }
       else
       {
@@ -162,23 +160,22 @@ void QgsMapToolClippingPlanes::canvasReleaseEvent( QgsMapMouseEvent *e )
         }
         catch ( const QgsCsException & )
         {
-          QgsMessageBar *msgBar = QgisApp::instance()->messageBar();
-          msgBar->pushWarning( QString(), tr( "Could not reproject the cross-section extent to 3D map coordinates." ) );
+          emit messageEmitted( tr( "Could not reproject the cross-section extent to 3D map coordinates." ), Qgis::MessageLevel::Warning );
         }
 
-        m3DCanvas->mapCanvas3D()->enableCrossSection(
+        m3DCanvasWidget->mapCanvas3D()->enableCrossSection(
           pt0,
           pt1,
           mRectangleWidth,
           true
         );
 
-        m3DCanvas->crossSectionToolFinished();
-
         const QgsSettings settings;
         QColor highlightColor = QColor( settings.value( QStringLiteral( "Map/highlight/color" ), Qgis::DEFAULT_HIGHLIGHT_COLOR.name() ).toString() );
         highlightColor.setAlphaF( 0.5 );
         mRubberBandPolygon->setColor( highlightColor );
+
+        emit finishedSuccessfully();
       }
     }
     else

src/app/3d/qgsmaptoolclippingplanes.h

@@ -52,6 +52,9 @@ class QgsMapToolClippingPlanes : public QgsMapTool
     //! Returns the Geometry of clipped area
     QgsGeometry clippedPolygon() const;
 
+  signals:
+    void finishedSuccessfully();
+
   private:
     void clearRubberBand() const;
 
@@ -59,7 +62,7 @@ class QgsMapToolClippingPlanes : public QgsMapTool
     QObjectUniquePtr<QgsRubberBand> mRubberBandLines;
     QObjectUniquePtr<QgsRubberBand> mRubberBandPoints;
     std::unique_ptr<QgsCoordinateTransform> mCt;
-    Qgs3DMapCanvasWidget *m3DCanvas = nullptr;
+    Qgs3DMapCanvasWidget *m3DCanvasWidget = nullptr;
     double mRectangleWidth = 0;
 };