[vtkusers] best way to cut volume

[David E DeMarle]

The type conversion happens because if you cut an arbitrary shape out of a
structured dataset the result is necessarily unstructured, unless the
arbitrary shape happens to be very regular like ExtractVOI's is.

vtkExtractSelectedFrustum can add cell and point data arrays called
"vtkInsidedness" so as to preserve the type of the data while performing an
extraction. In your downstream filters you could use that to do what you
want. For example you could use that array to make the opacity 0.0 outside
the region of interest in the transfer function.

That being said I don't know if there are any other filters that create that
array.

hth,
Dave DeMarle


On 3/2/07, Michael Knopke <Michael.Knopke at gmx.de> wrote:
>
> Hi,
>
> while I'm aware of class vtkExtractVOI, this is not what I want to
> achieve.
> vtkExtractVOI will let me extract only a box of interesst. I want to cut
> out
> any arbitrary shape (spline), so it's probably best to use an implicit
> function. There are several classes that work with implicit functions but
> always return unstructured grid. To still use the volumedata I need it to
> be
> vtkImageData. Can anybody help.
>
> I want to be able to extract only a part of my volume and visualize it
> with
> raycast or cut out unwanted parts that overlap the view.
>
> Thanks
>
> Michael
> --
> Ist Ihr Browser Vista-kompatibel? Jetzt die neuesten
> Browser-Versionen downloaden: http://www.gmx.net/de/go/browser
> _______________________________________________
> This is the private VTK discussion list.
> Please keep messages on-topic. Check the FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
> Follow this link to subscribe/unsubscribe:
> http://www.vtk.org/mailman/listinfo/vtkusers
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20070302/49a08864/attachment.htm>