[vtkusers] Re: Thresholding a vtkStructuredGrid -> vtkUnstructuredGrid?

[Thomas Deschamps]

Don't bother even looking at the question.
I just found that I was not obliged to have a structured grid with a 
point and vector structure defined at each regularly spaced point in space.
Sorry for my stupid question.

Thomas Deschamps wrote:

> Hi vtkUsers,
>
> I have a vtkStructuredGrid containing the components of a vector field 
> that I represent by means of vtkGlyph3D.
> In fact this is a representation of the gradient components of the 
> image at each pixel.
>
> The problem is that I have big images and I would like to remove the 
> vectors with small gradient magnitude from the final visualization.
> In fact I have so many vectors that sometimes my graphic card can't 
> stand it and the computer reboots...
>
> Rather than using vtkExtractGrid which uses a regular sampling rate, I 
> would like to choose which vectors are removed, based on my criterion.
> And I would like to still use vtkGlyph3D to represent the resulting 
> vector field.
>
> So I would like to know if there is a simple way to do that, or if 
> there isn't.
> Anyway thanks for reading this email.
>
> Thomas (tdeschamps at lbl.gov)
>