marking the inner part of the mesh

[Anatom]

Dear experts.
I am so much eager to have a script that might mark the inner located part of
the mesh.
Please see my animation of a sphere inside another as an example.
In fact the inner part may present a more compicated construction.
To operate it, I need to hide the outer part.
The best way I find is to first mark the inner mesh.

Is it possible to produce a script in order that to mark only the inner part (or just only the outer surface) of the whole mesh?


Anatom

[Anatom]