Simple menu in scene

I am looking to put a vtk menu in the scene where the volume is and have it locked to the camera. Does anyone have advice on what will need to be setup for this? Currently trying to follow reformat modules as an example.

In general, showing interactive widgets in a 3D rendering view is anything but simple.

In Slicer, we recently added right-click menu to markups in Slicer-4.11 and we are going to make the menu more configurable.

What exactly would like to do?