[vtkusers] Tetrahedral elements

Leila Baghdadi baghdadi at sickkids.ca
Wed Nov 20 12:04:36 EST 2002


Hi Hong

To my knowledge, there is nothing like this implemented in VTK. But I also 
remember very clearly when I applied the marching cubes algorithm on a 
binary image of carotid artery, it gave me a closed surface, i.e. the 
end-caps of arteries so if you do not get a closed surface when you apply 
marching cubes on your images, this just means

1) marching cubes is not the solution for you

2) try to implement an extra algorithm which would search for open areas 
and tries to fill them in

3) or should we ask my favorite BILL LORENSEN about this?

Hope this helps

Leila

 On Wed, 20 Nov 
2002, Hong Wan wrote:

> Hi Leila
> 
> Is it possible for vtk to close a surface with big holes or gap?? Or if
> you know of any alternative s/w that are able to do that. The presence
> of small holes or gaps is part and parcel of marching cubes algorithms
> and I am wondering if vtk has other classes available to address this
> problem.
> 
> Thanks
> 
> Hong Wan
> 
> -----Original Message-----
> From: vtkusers-admin at public.kitware.com
> [mailto:vtkusers-admin at public.kitware.com] On Behalf Of Leila Baghdadi
> Sent: Wednesday, November 20, 2002 12:14 AM
> To: Hong Wan
> Cc: 'Xiangyi Liu'; 'vtkuser maillist'
> Subject: RE: [vtkusers] Tetrahedral elements
> 
> Hi Hong
> 
> To my knowledge ICEM needs a closed surface in order to generate
> internal 
> tetrahedrals but you better check this through their website.
> 
> Hope this helps
> 
> 
> Leila
> 
> On Tue, 19 Nov 2002, Hong Wan wrote:
> 
> > Hi Leila,
> > 
> > Thanks for answering, I am also interested in this method. 
> > 
> > Using ICEM is it possible to close a gap or hole from the surface
> > generated from vtk?? I believed the import format to ICEM will be stl.
> > 
> > 
> > Regards
> > Hong Wan
> > 
> > -----Original Message-----
> > From: vtkusers-admin at public.kitware.com
> > [mailto:vtkusers-admin at public.kitware.com] On Behalf Of Leila Baghdadi
> > Sent: Tuesday, November 19, 2002 1:46 AM
> > To: Xiangyi Liu
> > Cc: vtkuser maillist
> > Subject: Re: [vtkusers] Tetrahedral elements
> > 
> > Hi  Xiangyi
> > 
> > I have done alot of FE mesh generation with VTK in the past and I can 
> > recall any method directly in VTK which will allow you to create 
> > tetrahedral elements out of a surface. The method we used was to
> create 
> > a surface using VTK and use a commercial package (ICEM) to generate 
> > internal tetrahedral elements.
> > 
> > Hope this helps
> > 
> > Leila
> > 
> > 
> > 
> >  On Mon, 18 Nov 2002, Xiangyi Liu wrote:
> > 
> > > Dear vtkusers:
> > > 
> > > I am a new user of vtk and still learning from the user's guide. Now
> I
> > have a 
> > > problem which I found no answer in the guide. I will aprreciate your
> > advice.
> > > 
> > > We have huge data files of microstructure image. We hope to mesh the
> > volume of 
> > > the stucture into tetrahedral elements with smooth triangulated
> > surface. The 
> > > surface part seems to be workabe, as to chopping the volume into
> > tetrahedral I 
> > > found no solution. I wonder if you have come across such problem
> > during your 
> > > use of vtk, and what you have done to overcome or bypass this
> problem.
> > > 
> > > Thank you for your help!
> > > 
> > > Xiangyi
> > > 
> > > -----------------------------------------------
> > > Xiangyi Liu
> > > Graduate Student
> > > Aerospace and Mechanical Engineering Department
> > > University of Notre Dame
> > > -----------------------------------------------
> > > 
> > > _______________________________________________
> > > This is the private VTK discussion list. 
> > > Please keep messages on-topic. Check the FAQ at:
> > <http://public.kitware.com/cgi-bin/vtkfaq>
> > > Follow this link to subscribe/unsubscribe:
> > > http://public.kitware.com/mailman/listinfo/vtkusers
> > > 
> > > 
> > 
> > _______________________________________________
> > This is the private VTK discussion list. 
> > Please keep messages on-topic. Check the FAQ at:
> > <http://public.kitware.com/cgi-bin/vtkfaq>
> > Follow this link to subscribe/unsubscribe:
> > http://public.kitware.com/mailman/listinfo/vtkusers
> > 
> > _______________________________________________
> > This is the private VTK discussion list. 
> > Please keep messages on-topic. Check the FAQ at:
> <http://public.kitware.com/cgi-bin/vtkfaq>
> > Follow this link to subscribe/unsubscribe:
> > http://public.kitware.com/mailman/listinfo/vtkusers
> > 
> > 
> 
> _______________________________________________
> This is the private VTK discussion list. 
> Please keep messages on-topic. Check the FAQ at:
> <http://public.kitware.com/cgi-bin/vtkfaq>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/vtkusers
> 
> _______________________________________________
> This is the private VTK discussion list. 
> Please keep messages on-topic. Check the FAQ at: <http://public.kitware.com/cgi-bin/vtkfaq>
> Follow this link to subscribe/unsubscribe:
> http://public.kitware.com/mailman/listinfo/vtkusers
> 
> 




More information about the vtkusers mailing list