[vtk-developers] New nonlinear celltypes

[David C. Thompson]

Soeren Gebbert wrote: 
> Indeed. Im trying to figur out what changes have to be made to fully
> support the cell types. I will have one week, maybe two for doing
> this, but im working only part time .... .
> And i would be realy happy if anybody can give me some hints or
> suggestions what is important to implement and which classes should be
> modified.
> 
> These are the classes i have figured out so far:
> ...
> Im not sure what to do:
> 
> Parallel/vtkExodusIIWriter.cxx
> Parallel/vtkEnSightWriter.cxx
> Hybrid/vtkExodusReader.cxx
I can take care of the Exodus reader and writer. As far as the Ensight
writer, the file format description is available in Chapter 11 of their
user manual:
http://www.ensight.com/pub/NEWEST_RELEASE/ensight80/doc/Manuals/UserManual.pdf
Ensight doesn't support those element types, so if a dataset contains
them, a single warning (as opposed to one for each element) should be
issued and then the writer should either
- demote the elements by eliminating nodes, or
- decompose the elements (effectively tessellating them), or
- omit the elements.
The Exodus reader/writer may end up doing the same for some of the
element types. I would omit them for the time being -- it's the
most conservative approach.

> Im not able to test everything. And because i have no knowledge in
> java and python, im not able to test the new cell types within  java
> and pyhton.
I don't think that will be a problem... not everything gets tested with
each wrapped language. I would get the Tcl wrappings working and leave
it at that unless someone complains. Since the wrapping is automated and
I don't see any mandatory entries in VTK/Wrapping/hints for cell
subclasses, I suspect the problems below are problems elsewhere that
manifest themselves as errors in the wrappings.

> In tcl i have some wired problems.
> For instance: the method GetCellType seems not to return the right
> Type in tcl?? I have to set the number by hand.
Hmmm. What exactly does it return?

> Extract edges works, but Contouring and clipping are not working!?
> I have tested these functions already in C++ and they working fine.
> 
> Can anybody help me what i have to consider or what im doing wrong?
If you describe the errors in more detail or make your code available, I
will try.

> btw.:
> please excuse my english, im not a native speaker.
Your English is much better than my German.

	David