More precise clipping with implicit functions

[John Biddiscombe]

Dear All,

Given an implicit function and a dataset, vtkClipPolyData inspects each
point in the dataset, evaluates the function and either accepts or rejects
it based upon the value. So far so good.

If the polygonal surface is large compared to the function, the function
may intersect a polygonal face, but not overlap any of the defining points.

Is there a filter which simply returns all 'cells' which overlap the
functional surface, rather than all 'points' which overlap?

I suspect there is not. If not, is there a simple way of finding cells
which bound the surface but are don't pass the "point overlap" test?

thanks

John B

eg

square outer polygon.....small inner circular fn....very bad picture
------------
|           |
|  ___      |
|  | |      |
|  ---      |
|           |
------------



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