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<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>Thank you for the e-mail!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>I’ve already tried
the Delaunay triangulation, but, as you say, the problem is it only returns a
convex hull… </span></font><font size=2 color=navy face=Wingdings><span
lang=EN-GB style='font-size:10.0pt;font-family:Wingdings;color:navy'>J</span></font><font
size=2 color=navy face=Arial><span lang=EN-GB style='font-size:10.0pt;
font-family:Arial;color:navy'><o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>Many thanks,<o:p></o:p></span></font></p>
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style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'>Paulo<o:p></o:p></span></font></p>
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style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>De:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Meisam Aliroteh
[mailto:meisam.aliroteh@gmail.com] <br>
<b><span style='font-weight:bold'>Enviada:</span></b> quarta-feira, 19 de
Setembro de 2007 3:42<br>
<b><span style='font-weight:bold'>Para:</span></b> <st1:PersonName
ProductID="Paulo Bernardes" w:st="on">Paulo Bernardes</st1:PersonName><br>
<b><span style='font-weight:bold'>Cc:</span></b> vtkusers@vtk.org<br>
<b><span style='font-weight:bold'>Assunto:</span></b> Re: [vtkusers] Outer
polygon of an arbitrary point cloud</span></font><o:p></o:p></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='margin-bottom:12.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>You can use Delaunay
triangulation (vtkDelaunay2D or vtkDelaunay3D). But keep in mind that this
algorithm only returns the convex hull of a point cloud. I just remembered that
there is also another algorithm called Quick Hull (google search for QHull). This
algorithm also returns a convex hull. I'm not sure if there is an algorithm
that can actually handle both convex and concave hulls (as far as I know
getting a concave hull is a much more difficult task than a convex hull). <o:p></o:p></span></font></p>
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<p class=MsoNormal><span class=gmailquote><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'>On 9/18/07, <st1:PersonName ProductID="Paulo Bernardes"
w:st="on"><b><span style='font-weight:bold'>Paulo Bernardes</span></b></st1:PersonName>
<<a href="mailto:pbernardes@uaum.uminho.pt">pbernardes@uaum.uminho.pt</a>>
wrote:</span></font></span> <o:p></o:p></p>
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<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>Dear
all,</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'> </span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'>Is there any way to determine the outer polygon of an arbitrary point
cloud using VTK?</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'> </span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'>Many Thanks</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'> </span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'>Paulo</span></font><o:p></o:p></p>
<p><font size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:
Arial'> </span></font><o:p></o:p></p>
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