# detect large curvature

**URL:** https://discourse.vtk.org/t/detect-large-curvature/3933
**Category:** Support
**Created:** [August 7, 2020, 9:28am UTC](https://discourse.vtk.org/t/detect-large-curvature/3933 "2020-08-07T09:28:57Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Daniel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/d/3ec8ea/32.png) [@Daniel](https://discourse.vtk.org/u/Daniel)
#### Post date: [August 7, 2020, 9:28am UTC](https://discourse.vtk.org/t/detect-large-curvature/3933/1 "2020-08-07T09:28:57Z")

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Hi there,

I have a vtkPolyData on which I want to detect “_strong_” curvatures. At best the coordinates of these places should be stored.  
In the screenshot a possible situation is circled.  
 ![curvature_001](https://discourse.vtk.org/uploads/default/original/2X/4/422bc9a1a8b91f7fcf87406c5038ddaa88a61d8c.jpeg)  
Here the whole encircled area shall be examined for a (large) curvature, not over single vertices.  
Here the upper tip should be recognized as the result.

Is it possible to apply vtkCurvature directly to only a certain area (cells) of a vtkPolydata object?  
Not on the whole object, but only on a part of the vtkPolyData, without having selected the area before.  
Perhaps via a defined/selected cell, of which only a certain number of other neighboring cells are examined.

Any hint is welcome.