[vtkusers] vtkUnstructuredGrid: How to unify two instances to a single one?

[Rudolf Reinhard]

Dear all,

you hope that much you can help me. As a newbie in vtk I have a problem, 
which I am not able to solve so far. I am trying at it for some time now 
and I am forced to present a solution next week.

That's why I am asking you. So I start with its description.

Suppose one has two instances of unstructured grids as input (i.e., two 
instances of  vtkUnstructuredGrid). What is to do to obtain one instance 
of an unstructured grid, which "consists" of the two grids given as 
input (Or in other words: How to glue them to each other such that there 
is only one)?

It is really necessary to obtain one single geometry as output. By using 
ParaView (version 3.8.0) there are two ways to check if the obtained 
result corresponds to the required one. The first way is to apply the 
Connectivity filter: The requested result is to get a single coloured 
surface. The second way is to apply the Clip filter after having 
extracted the grid's surface: The requested result is to obtain a single 
contour without any lines inside of it, regardless of the cutting 
plane's position (such that it is continuously transformable into a 
circle line).

The obtained results do not satisfy these needs so far. Though it is 
quite easy to get a representation of both of the grids in a single 
vtk-file. But this is just necessary and not sufficient.

I hope to have given an usable description of my problem and that you 
believe me, that this posting is the cry for help after having no idea 
and (this is much worse) soonly no time anymore to work at it.

I appreciate any help.


Thanks in advance,
Rudi