Q: Isosurface pipeline ???

[Gala'Vi and Liss @ Mainframe Country]

Just take that structured points dataset and feed it to the
vtkContourFilter. Do this:

	reader (to read a vtkStructuredPoints dataset)

	vtkContourFilter (which will figure out which contouring algorithm
                          to use on your particular data)

	vtkPolyDataMapper
	vtkActor

Try this, works for me.
Gala'Vi
NCSA, UIUC

//***********************************************
  -- There is always a way, 
        you just have to find it.
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//***********************************************

On Tue, 22 Jun 1999, Audrius Stundzia wrote:

> Dear vtker's
> 
> I would like  to compute an isosurface of the scalars S = S(x,y,z)
> associated
> with a structure point data set.
> 
> I'm using the following pipeline to try to generate such an isosurface
> from
> a 128 x 128 x 23 slice data set.  I've loaded and displayed the 2D
> slices without
> any problem. Now I'm trying to generate an isosurface. So far without
> success.
> 
> The pipeline.
> 
>    vtkScalars
> 
>    vtkStructuredPoints
> 
>    vtkImplicitVolume
> 
>    vtkSampleFunction
> 
>    vtkMarchingSquares
> 
>    vtkPolyDataMapper
> 
>    vtkActor
> 
> The vtkScalars object is loaded into an vtkStructuredPoints object
> 
> points->GetPointData()->SetScalars( scalars)
> 
> The above pipeline gives me a blank screen (just background).
> 
> Are the scalars passed down the pipeline?
> What methods should I use to make that they are and that
> their isosurface is calculated?
> 
> In the VTK 2nd ed. pg. 508 example:
> 
> Why in the vtkPolyDataMapper object is the following method used?
> 
> skinMapper->ScalarVisibilityOff();
> 
> Similarly, in the pg. 520 example, the vtkMarchingCubes object uses the
> following method.
> 
> mcubes->ComputeScalarsOff()
> 
> Why?
> 
> Any pointers (pun intended) would be most appreciated.
> 
> Audrius Stundzia
> 
> IBMG
> 
> 
> 
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