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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have a vtkPolydata 3D surface comprised of triangles<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>with scalar values associated with the point data. I want<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>to remove all triangles having a scalar value of 0 at all<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>three points of the triangles. After which, I want to
measure<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>the volume of the surface using vtkMassProperties. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>vtkThreshold does almost exactly<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>what I need with the exception that it outputs a<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>vtkUnstructuredGrid and not a vtkPolyData. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>vtkThreshold* threshold =
vtkThreshold::New();<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>threshold->SetInputConnection(
poly );<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>threshold->AllScalarsOn();<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>threshold->SetPointsDataTypeToFloat();<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>threshold->SetAttributeModeToUsePointData();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>threshold->ThresholdByUpper( 0 );<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>How can I recover a vtkPolyData? I have<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>seen vtkUnstructuredGridToPolyDataFilter<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>but this is an abstract class.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Dean<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Dean Inglis, PhD<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>~~~~ Center for Appendicular ~~~~~<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Magnetic Resonance Imaging Studies<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>610 - <st1:Street w:st="on"><st1:address w:st="on">25
Charlton Ave. E.</st1:address></st1:Street><o:p></o:p></span></font></p>
<p class=MsoNormal><st1:place w:st="on"><st1:City w:st="on"><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>Hamilton</span></font></st1:City><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>,
<st1:State w:st="on">Ontario</st1:State>, <st1:PostalCode w:st="on">L8N 1Y2</st1:PostalCode></span></font></st1:place><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Assistant Professor (Adjunct)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Department of Civil Engineering<o:p></o:p></span></font></p>
<p class=MsoNormal><st1:place w:st="on"><st1:PlaceName w:st="on"><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>McMaster</span></font></st1:PlaceName><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>
<st1:PlaceType w:st="on">University</st1:PlaceType></span></font></st1:place><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal><st1:place w:st="on"><st1:City w:st="on"><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>Hamilton</span></font></st1:City><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'>,
<st1:State w:st="on">Ontario</st1:State></span></font></st1:place><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face="Courier New"><span style='font-size:
10.0pt;font-family:"Courier New"'>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~</span></font><o:p></o:p></p>
<p><font size=2 face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New"'>Software Demos:<o:p></o:p></span></font></p>
<p class=MsoAutoSig><font size=2 face="Courier New"><span style='font-size:
10.0pt;font-family:"Courier New"'><a
href="http://www.youtube.com/watch?v=_zYNtHC9-0s">http://www.youtube.com/watch?v=_zYNtHC9-0s</a><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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