[vtkusers] RemoveViewProp then AddViewProp of same actor changes results?

[Sean McBride]

On Thu, 19 Jan 2017 16:59:09 -0500, Ken Martin said:

>It should be the same unless any of the actors are coincident or
>translucent. In that case the order of the actors can make a difference.
>alpha blending for transparency is order dependent and with coincident
>geometry either first or last wins (I forget which in VTK). Not sure if
>that applies in your example.

The green thing in my screenshot is indeed translucent.  Making it fully opaque indeed "fixes" the problem.

I don't think I have anything coincident, though things overlap.

So how do I control the order?  vtkViewport.h has AddViewProp() but I don't see any API to, for example, add it first or last.  And vtkPropCollection's docs say that it's 'unsorted'.

Thanks Ken!

Sean