Screen-space ambient occlusion for volume rendering

You can set those information keys in Slicer in Python like this:

threeDViewWidget =
vrDisplayableManager = threeDViewWidget.threeDView().displayableManagerByClassName("vtkMRMLVolumeRenderingDisplayableManager")

volumeNode = slicer.mrmlScene.GetFirstNodeByClass('vtkMRMLVolumeNode')

volumeActor = vrDisplayableManager.GetVolumeActor(volumeNode)
info = volumeActor.GetPropertyKeys()
if not info:
    info = vtk.vtkInformation()
info.Set(vtk.vtkOpenGLActor.GLDepthMaskOverride(), 1)

Would it be possible to set enable depth mask override by default to avoid the need for such low-level manipulations? None of the other volume rendering techniques require such calls.

If there are some negative side-effects of enabling depth mask override in some cases then making it optional could make sense, but then there should be more convenient API, for example a method in vtkVolume.