[vtkusers] delaunay3d: degenerate triangles encountered

[John Harris]

... so do you think that the problem is the way I read in my mesh? i.e. the 
way I create my vtkUnstructuredGrid??
Are there any filters I should use that could prevent the problems I'm 
getting? :s
Any suggestions are appreciated,
Thanks again..
JH


>Subject: Re: [vtkusers] delaunay3d: degenerate triangles encountered
>
>Thanks all for your responses,
>
>My data is actually from an unstructured grid which is composed of 
>tetrahedra, I then use GeometryFilter to convert the tetrahedra to 
>triangles
>
>Acutally here is my pipeline:
>
>	GeometryFilter
>	DecimatePro
>	PolyDataNormals
>	Delaunay3D
>
>My tolerance is also positive and is set to 0.01.
>
>I even tried passing my decimate object through vtkSmoothPolyDataFilter 
>first as someone had suggested in a previous post, but this doesnt solve 
>the problem.
>
>So not only do I get degenerate triangles, but sometimes my program will 
>crash due to " *** glibc detected *** double free or corruption: "
>
>Here is my exact code:
>
>	GeometryFilter->SetInput( Ugrid );
>	DecimatePro->SetInput( GeometryFilter->GetOutput() );
>	DecimatePro->SetTargetReduction( 0.9 );
>	DecimatePro->PreserveTopologyOn();
>
>	PolyDataNormals>SetInput( DecimatePro->GetOutput() );
>	PolyDataNormals->ConsistencyOn();
>	PolyDataNormals->AutoOrientNormalsOn();
>
>	Delaunay3D->SetInput( PolyDataNormals->GetOutput() );
>	Delaunay3D->SetTolerance (0.01);
>	Delaunay3D->SetAlpha(0.0);
>	Delaunay3D->BoundingTriangulationOff();
>	Delaunay3D->Update();
>	Delaunay3D->Modified();
>
>If anyone has any insight that would be great!!
>Thank you!!
>JH
>
>
>>From: "Kevin H. Hobbs" <kevin.hobbs.1 at ohiou.edu>
>>Reply-To: hobbsk at ohiou.edu
>>To: Amy Squillacote <amy.squillacote at kitware.com>
>>CC: vtkusers at vtk.org, John Harris <lost_bits1110 at hotmail.com>
>>Subject: Re: [vtkusers] delaunay3d: degenerate triangles encountered
>>Date: Mon, 15 Aug 2005 12:04:30 -0400
>>
>>On Mon, 2005-08-15 at 08:47 -0400, Amy Squillacote wrote:
>> > The error message is being produced by vtkDelaunay3D.  It probably
>> > means you have "triangles" in your data set where at least two of the
>> > points in a single triangle are coincident.
>> >
>> > - Amy
>>
>>I just got the same error with a positive tolerance. The tolerance
>>parameter should discard coincident points.
>>
>>My data are from a regular lattice and so fit the warning in the
>>doxygen.  Are yours?
>><< signature.asc >>
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