[vtkusers] Re: Speed up vtkKdTree::FindClosestPoint

[lee ann fisk]

On Tue, 2005-02-01 at 09:33, sigmunau at idi.ntnu.no wrote:
> At last a question about the KdTree: Would it be possible to extend this
> class to also support finding closest point on a more general dataset?	I am
> thinking about something like this: 
> * Find closest point among cell-node and cell centroids
> * Find closest point on cell(s) containing this point.
> * Return closest point of points return in above statement.
> 
> I guess this approch isn't 100% correct in all situations, but will do very
> often provided the dataset doesn't represent too exotic shapes.

The locator is built from a list of points, and doesn't know
about cell membership.  I think you would need to write
another BuildLocatorFromPoints that also takes a vtkCellArray
and a location array (giving the location of the start of
each cell in the vtkCellArray), and manages these lists along
with the list of points.  Then you could answer cell-based
queries.

Lee Ann

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Lee Ann Fisk                                 lafisk at sandia.gov
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Discrete Algorithms and Math                  Fax 505-845-7442
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