Plug-in RenderView Object and Caption

Hi experts,
I am new to developing paraview (pv) plug-in and am trying to display an object with a caption in the renderview. I was able to create the below image in python VTK where I added a cylinder and an “vtkCaptionActor2D()” actor to the renderer.

I need to create similar functionality in a plug-in in ParaView. However, I cannot figure out how to get access to the pv renderer and add the caption actor. Or may be, return a single object by “grouping” the cylinder and caption (not sure how to “combine” or “group”).

If it helps below is my “RequestData()” function.

1. int MyPlugin::RequestData(vtkInformation* vtkNotUsed(request),
2.   vtkInformationVector** vtkNotUsed(inputVector), vtkInformationVector* outputVector)
3. {
4.     auto cyl = vtkCylinderSource::New();
5.     cyl->SetCenter(0, 0, 0);
6.     cyl->SetHeight(100);
7.     cyl->SetRadius(1);
8.     cyl->SetResolution(50);
9.     cyl->Update();

10.     auto caption = vtkCaptionActor2D::New();
11.     caption.SetCaption("Test Caption");

12.     auto outInfo = outputVector->GetInformationObject(0);
13.     auto outObj = outInfo->Get(vtkDataObject::DATA_OBJECT());
14.     outObj->ShallowCopy(cyl->GetOutput());

15.     return 1;
16. } 

Any suggestions or example would be helpful.



I am not an expert and this is a shot in the dark but looking at this Caption Widget Example, the vtkCaptionActor2D() is a property of an axes or a representation.

In the RequestData() function you only usually get the data of the source. I think you will have to set the caption elsewhere in your code where the view is being rendered.

Thanks John.
My only objective is to create a 3D object with a descriptive text in a paraview plug-in. It does not have to use vtkCaptionActor2D() or be inside the function RequestData().

For now, I am using the vtkAppendPolyData to append a cylinder and vtkVectorText inside the RequestData().


This works, however I guess font and color cannot be updated, since pv renderer is needed for that. Unfortunately, I am unable to find how to get access to the paraview renderer. Will keep trying.


For anyone facing similar issue
Access to the Mapper in the Paraview is explained in the section “Adding new Representations for 3D View using Plugins * new in version 3.7” on the page


This is higly outdated, here is the correct page: ParaView: Plugin Howto