[vtkusers] Extract a VOI from volume

[David Doria]

> But vtkbox widget only give me transformation matrix
>
> Vtkextractvoi need more information or example to know if I can use
>
> This function to extract data out from 3D volume.
>
>
>
> Thanks for reply or some example

You have to SetVOI on the ExtractVOI filter to the appropriate
coordinates of the box widget (get a vtkBoxRepresentation from the
boxWidget, get the polydata, then use GetPoint)

http://www.vtk.org/Wiki/VTK/Examples/Cxx/ImageData/ExtractVOI
http://www.vtk.org/Wiki/VTK/Examples/Cxx/Widgets/BoxWidget2

Hope that helps,

David