[vtkusers] world coordinates and image data

[Karthik Krishnan]

On Wed, Feb 25, 2009 at 11:11 PM, Richard Beare <richard.beare at gmail.com>wrote:

> Hi,
> I'm trying to track down appropriate vtk data representations for
> displaying multiple image data sets in correct relationships to one
> another. The source data is MRI slices.
>
> Does the vtkImageData type have the option of image axes not being
> aligned to world coordinates?


no


> Assuming this isn't possible, what is the most appropriate data
> structure to use. The approach I'm thinking of is to iterate over the
> image in ITK, looking up world coordinates for each voxel, and
> building a large vtk data structure that I'd then save in a paraview
> compatible format.


We tend to keep the image data in its local (axis aligned) coordinate
system. You can manage local to world coordinate system mapping at the actor
level by setting a user transform (see SetUserTransform) on the actor
visualizing your data.

However, if you are looking to transform the data itself, your only option
is to transform the imagedata to polys using vtkImageDataGeometryFilter and
then transforming this using vtkTransformPolyDataFilter.


>
> Any recommendations?
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Please keep messages on-topic and check the VTK FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
>
> Follow this link to subscribe/unsubscribe:
> http://www.vtk.org/mailman/listinfo/vtkusers
>



-- 
Karthik Krishnan
R&D Engineer,
Kitware Inc.
Ph: 518 371 3971 x119
Fax: 518 371 3971
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20090225/88d77b5a/attachment.htm>