[3D] correctly compute near/far planes when a scene is reloaded (qgis…

…#55632)

* qgs3dmapcanvaswidget: Directly use canvas cameracontroller method

* qgs3dmapcanvas: Update the navigation widget on near/far plane changes

`Qgs3DNavigationWidget` is updated when the camera parameters are
updated by `QgsCameraController`. However, the near far planes of the
camera can be updated from the `Qgs3DMapScene`. In that case, the
`Qgs3DNavigationWidget` also neeeds to be updated.

This issue is fixed by listening to the near/far plane changes from
the scene camera in `Qgs3DMapCanvas`.

* qgs3dmapscene: Ensure to update near/far planes on new entity creation

The near/far planes are computed in `Qgs3DMapScene` when the camera
parameters have changed. Their values depend on the bounding boxes of
the visible entities. However, the near and far planes are not
recomputed when a new entity is added.
This can be problematic for entities from a vector layer because their
vertical extent is unknown when the associated bounding boxes are
created.

This issue is fixed by calling
`Qgs3DMapscene::updateCameraNearFarPlanes` when a new scene entity is
created. Indeed, on a new scene entity, the exact exact bounding box
has been computed by the loader of the chunked entity.

src/3d/qgs3dmapscene.cpp

@@ -698,6 +698,8 @@ void Qgs3DMapScene::addLayerEntity( QgsMapLayer *layer )
         connect( sceneNewEntity, &Qgs3DMapSceneEntity::newEntityCreated, this, [this]( Qt3DCore::QEntity * entity )
         {
           finalizeNewEntity( entity );
+          // this ensures to update the near/far planes with the exact bounding box of the new entity.
+          updateCameraNearFarPlanes();
         } );
 
         connect( sceneNewEntity, &Qgs3DMapSceneEntity::pendingJobsCountChanged, this, &Qgs3DMapScene::totalPendingJobsCountChanged );

src/app/3d/qgs3dmapcanvaswidget.cpp

@@ -393,7 +393,11 @@ void Qgs3DMapCanvasWidget::setMapSettings( Qgs3DMapSettings *map )
   connect( mCanvas->scene(), &Qgs3DMapScene::totalPendingJobsCountChanged, this, &Qgs3DMapCanvasWidget::onTotalPendingJobsCountChanged );
   connect( mCanvas->scene(), &Qgs3DMapScene::gpuMemoryLimitReached, this, &Qgs3DMapCanvasWidget::onGpuMemoryLimitReached );
 
-  mAnimationWidget->setCameraController( mCanvas->scene()->cameraController() );
+  // update the navigation widget when the near/far planes have been updated by the map scene
+  connect( mCanvas->cameraController()->camera(), &Qt3DRender::QCamera::nearPlaneChanged, mNavigationWidget, &Qgs3DNavigationWidget::updateFromCamera );
+  connect( mCanvas->cameraController()->camera(), &Qt3DRender::QCamera::farPlaneChanged, mNavigationWidget, &Qgs3DNavigationWidget::updateFromCamera );
+
+  mAnimationWidget->setCameraController( mCanvas->cameraController() );
   mAnimationWidget->setMap( map );
 
   // Disable button for switching the map theme if the terrain generator is a mesh, or if there is no terrain