Add vtkLightBoxRendererManager::GetCornerAnnotation convenient method

Libs/Visualization/VTK/Core/vtkLightBoxRendererManager.cpp

@@ -709,6 +709,12 @@ const std::string vtkLightBoxRendererManager::GetCornerAnnotationText() const
 }
 
 // --------------------------------------------------------------------------
+vtkCornerAnnotation * vtkLightBoxRendererManager::GetCornerAnnotation() const
+{
+  return this->Internal->CornerAnnotation;
+}
+
+// --------------------------------------------------------------------------
 void vtkLightBoxRendererManager::SetBackgroundColor(const double newBackgroundColor[3])
 {
   if (!this->IsInitialized())

Libs/Visualization/VTK/Core/vtkLightBoxRendererManager.h

@@ -114,6 +114,10 @@ class CTK_VISUALIZATION_VTK_CORE_EXPORT vtkLightBoxRendererManager : public vtkO
   /// Get current corner annotation
   const std::string GetCornerAnnotationText()const;
 
+  /// Get corner annotation actor
+  /// The same annotation is associated with all renderers managed by the light box
+  vtkCornerAnnotation * GetCornerAnnotation()const;
+
   /// Set background color
   void SetBackgroundColor(const double newBackgroundColor[3]);