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<meta name="viewport" content="width=device-width" /><meta http-equiv="Content-Type" content="text/html;charset=utf-8" /></head><body>Hi Fantasy,<br>
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Points alone, generally, can't define a 3D polytope. You need points (vertices) and the edges. This result is called Cauchy lemma. <br>
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If you have a list of edges along with vertices, then you have a graph. you can now search this graph for cycles. If you tell us whether you are using C++ or python, we can assist you with the search.<br>
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A special case, of course, is the convex hull mentioned.<br>
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Diese Nachricht wurde von meinem Android Mobiltelefon mit GMX Mail gesendet.<br><br><div style="line-height: 1; padding: 0.3em">Am 01.02.2016, 20:59, David Gobbi <david.gobbi@gmail.com> schrieb:<blockquote class="gmail_quote" style="margin: 0.8ex 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
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Hi Fantasy,
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If the points are a convex hull, then you can use vtkDelaunay3D to fill the hull with tetrahedrons, followed by vtkDataSetSurfaceFilter to get just the outer surface.
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- David
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On Mon, Feb 1, 2016 at 12:27 PM, Chen, Lifan<span> <<a href="mailto:LCHEN41@mgh.harvard.edu" target="_blank">LCHEN41@mgh.harvard.edu</a>></span> wrote:<br />
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<font face="Tahoma">I've read the code. In this example, it requires user to define the faces of the polyhedron, however, what I want is to automatically create the polyhedron with the given points based on some kind of rules, for example, the closest points rule. I know there is a method in vtkSelectPolyData to finish the similar work, but the method in vtkSelectPolyData does not create a polydata itself.</font>
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<font face="Tahoma">Fantasy</font><br />
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<font color="#000000" face="Tahoma" size="2"><b>发件人:</b> vtkusers [<a href="mailto:vtkusers-bounces@vtk.org" target="_blank">vtkusers-bounces@vtk.org</a>] 代表 Meehan, Bernard [<a href="mailto:MEEHANBT@nv.doe.gov" target="_blank">MEEHANBT@nv.doe.gov</a>]<br />
<b>发送时间:</b> 2016年2月1日 13:22<br />
<b>收件人:</b><a href="mailto:vtkusers@vtk.org" target="_blank"> vtkusers@vtk.org</a><br />
<b>主题:</b> Re: [vtkusers] How to create a polyhedron(vtkPolyData) from a series of points(Vertex)<br />
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I think that this might help:
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<a href="http://www.vtk.org/Wiki/VTK/Examples/Cxx/GeometricObjects/Polyhedron" target="_blank">http://www.vtk.org/Wiki/VTK/Examples/Cxx/GeometricObjects/Polyhedron</a>
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<span style="font-weight: bold;">From:</span> vtkusers <<a href="mailto:vtkusers-bounces@vtk.org" target="_blank">vtkusers-bounces@vtk.org</a>> on behalf of "Chen, Lifan" <<a href="mailto:LCHEN41@mgh.harvard.edu" target="_blank">LCHEN41@mgh.harvard.edu</a>><br />
<span style="font-weight: bold;">Date:</span> Monday, February 1, 2016 at 8:09 AM<br />
<span style="font-weight: bold;">To:</span> "<a href="mailto:vtkusers@vtk.org" target="_blank">vtkusers@vtk.org</a>" <<a href="mailto:vtkusers@vtk.org" target="_blank">vtkusers@vtk.org</a>><br />
<span style="font-weight: bold;">Subject:</span> [vtkusers] How to create a polyhedron(vtkPolyData) from a series of points(Vertex)<br />
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<font size="3">Hey all,</font>
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<font size="3">I am new in vtk and here is a simple issue. How could I create a polyhedron from a series of points which are the vertexs of the polyhedron. Of course, these points do not intersect. Does any one know any method in vtk to accomplish this?</font>
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<font size="3">Thanks,</font>
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<font size="3">Fantasy</font>
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