[vtkusers] detecting if surface is convex

[Dominik Szczerba]

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Another idea: you can use e.g. qhull to compute the convex hull of your
mesh. If the mesh is convex the resulting volume will not change.

Dominik

Dominik Szczerba wrote:
> Curvature?
> 
> But will probably not be more robust than angles.
> 
> Dominik
> 
> Bryn Lloyd wrote:
>> Hi,
> 
> 
>> Is there any code in VTK that would help with detecting if a closed 3d
>> surface (or equivalently a connected set of tetrahedra) is convex or
>> concave?
> 
>> My own attempts have been to compute the dihedral angles at each edge on
>> the surface. If at least one is larger than PI -> concave. This is not
>> very robust though, especially for flat surfaces.
> 
> 
>> Thanks
>> Bryn
> 
> 
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- --
Dominik Szczerba, Ph.D.
Computational Physics Group
Foundation for Research
on Information Technologies in Society
http://www.itis.ethz.ch
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