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Hi,<br>
many thanks for your answers and suggestions.<br>
<br>
David C. Thompson wrote:
<blockquote cite="mid1134781822.24332.1520.camel@fozzy.ran.sandia.gov"
type="cite">
<blockquote type="cite">
<pre wrap="">One question I have on the use of a generic cell adaptor approach is the
recovery of the original cell edges for use in wire frame views. In VTK
4, I use an unstructured grid surface filter which preserves nonlinear
faces and saves Face Id's which are used in edge filters to detect
boundary edges and internally triangulated edges.
</pre>
</blockquote>
<pre wrap=""><!---->There isn't an equivalent filter for the generic dataset yet. The
closest matches are the vtkGenericGeometryFilter (doesn't store cell ID
or face ID with resulting geometry) and the vtkGenericDataSetTessellator
(doesn't take lower-dimensional boundaries, but can store cell IDs with
resulting geometry).
</pre>
</blockquote>
That was one important reason for us to implement the new cell types in
VTK. And because we need the cell informations <br>
while processing the data, we can not use the tessellator to create an
approximation. The extrapolation and<br>
interpolation algortihm i have designed (maybe bad, but fast) are not
working anymore in this case. <br>
We need exact point, cell and face ids. Also we need to use shrink,
threshold and other filter bevor tessellation.<br>
<br>
<blockquote cite="mid1134781822.24332.1520.camel@fozzy.ran.sandia.gov"
type="cite">
<blockquote type="cite">
<pre wrap="">Perhaps of more general interest is the question of user contributions
which are documented and tested but not implemented in all VTK classes.
Insisting on a 100% complete implementation seems to me to be too
onerous and could potentially stifle all but the smallest of
contributions.
</pre>
</blockquote>
<pre wrap=""><!---->Obviously, Kitware has the final say, but here's my 2 cents. It sounds
like Soeren is most of the way there. And while I agree that it makes
the barrier high, VTK would quickly turn into a very difficult piece of
software to use otherwise. It's not that everything has to be there on
the first checkin, but there has to be a commitment to follow through.
If it was simply a filter that only handled a subset of cell types
(consider some of the volume renderers that only work on tetrahedra), it
might be one thing -- but the cell API is deeply involved in the VTK
framework.
</pre>
</blockquote>
Indeed. Im trying to figur out what changes have to be made to fully
support the cell types.<br>
I will have one week, maybe two for doing this, but im working only
part time .... .<br>
And i would be realy happy if anybody can give me some hints or
suggestions what is important to implement<br>
and which classes should be modified.<br>
<br>
These are the classes i have figured out so far:<br>
Already modified:<br>
<br>
Filtering/vtkUnstructuredGrid.h .cxx .h<br>
Graphics/VtkDataSetSurfaceFilter.cxx<br>
Graphics/vtkCutter.cxx<br>
Graphics/vtkGeometryFilter.cxx<br>
Graphics/vtkBoxClipDataSet.cxx<br>
Filtering/vtkGenericCell.h .cxx<br>
<br>
Im not sure what to do:<br>
<br>
Parallel/vtkExodusIIWriter.cxx<br>
Parallel/vtkEnSightWriter.cxx<br>
Hybrid/vtkExodusReader.cxx<br>
<br>
<br>
Im not able to test everything. And because i have no knowledge in java
and python, im not able to<br>
test the new cell types within java and pyhton.<br>
<br>
Im currently implementing tests in TCL:<br>
clipQuadraticCells.tcl and ExtractEdgesQuadraticCells.tcl<br>
<br>
In tcl i have some wired problems.<br>
For instance: the method GetCellType seems not to return the right Type
in tcl?? I have to set the number by hand.<br>
Extract edges works, but Contouring and clipping are not working!?<br>
I have tested these functions already in C++ and they working fine.<br>
<br>
Can anybody help me what i have to consider or what im doing wrong?<br>
<br>
Best regards<br>
Sören Gebbert<br>
<br>
btw.:<br>
please excuse my english, im not a native speaker.<br>
<br>
<br>
<br>
<br>
<br>
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