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Hi Terry-<br>
<br>
Here's what I would do. Create in one file the geometry, in your case
structured points. Then in another file create field data (that contains
your dataset attributes). One reader reads the geometry, the other (an
instance of vtkDataObjectReader) the field data. Then merge them
together to create a dataset with associated field data. The key
(surprisingly enough :) is vtkMergeDataObjectFilter. There is a script
vtk/graphics/examplesTcl/mergeDataObject.tcl that demonstrates how this
is done. Note that you usually also have to use
vtkFieldDataToAttributeDataFilter to create the attributes (e.g.,
vectors, scalars, etc.) from the field data that is merged into the
geometry.<br>
<br>
Will<br>
<br>
<br>
<br>
At 10:52 AM 8/22/2000 -0700, Terry J. Ligocki wrote:<br>
<blockquote type=cite cite>I have been using, creating, and reading VTK
data files (especially Poly Data, Structured Points, and Structured
Grids) for some time now and I have one major question/comment: <br>
<br>
Is there any way in the current format to reference data in another file
(short of replicating that data in the current file - which isn't a
reference anyway, :-)? <br>
<br>
For example, I have a file with (x,y,z) coordinates for a Structured Grid
and hundreds of time steps of scalar data. The coordinates don't
change with time. Currently, I seem to have one of two choices:
<ul>
<li>Create a Structured Grid file for each time step with a copy of the
(x,y,z) coordinates and the data - this creates a lot of redundant data
(the coordinates) and increases the size of the data set by about a
factor of 4.
</ul>
<ul>
<li>Create a Structured Grid file for the coordinates with no data,
create a Structured Points file for each time step with the data, read
the Structured Grid once, and for each time step read the a Structured
Points and set the Structured Grid's point data to the Structured Points'
point data. This is what I do and it works but it seems a little
weird, :-).
</ul>Also, in general, I often have "raw" ASCII or binary data
(meaning data or coordinates with no dimensional information) available
in some files and I'd like to generate a VTK file which references this
data without concatenating everything together into one file.
Basically, I'd like to be able to "include" other files in a
VTK data file. It could, of course, be made more complex but this
would be enough to cover most of the things I have come across. <br>
<br>
Is something like this already possible? If not, I'd be interested
to helping add it but I wanted to make sure it wasn't already possible
and then to discuss how to implement it. I think it would be a good
idea to add a very simple extension and then think/worry about more
sophisticated extensions. <br>
<br>
That's all for now... <br>
<br>
Terry J. (Ligocki, tjligocki@lbl.gov, (510)486-6140)
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