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<TITLE>Modified vtkTubeFilter</TITLE>
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<P><FONT SIZE=2>Hello all vtk users,</FONT>
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<P><FONT SIZE=2>I have made a simple modification to vtkTubeFilter. I'll just include the e-mail I sent to kitware.</FONT>
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<P><FONT SIZE=2>------------------</FONT>
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<P><FONT SIZE=2>Dear Kitware,</FONT>
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<P><FONT SIZE=2>I have made a minor modification to VTK that I would like to see included.</FONT>
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<P><FONT SIZE=2>The modification is to the class vtkTubeFilter. This class offers a method to vary the radius of the tubes being generated by scalar values, SetVaryRadiusToVaryRadiusByScalar. This method linearly adjusts the radius of the tubes based on the scalar value. I added just one method which I call SetVaryRadiusToVaryRadiusByAbsoluteScalar. This method sets the radius of the tubes to be exactly the scalar value. A warning is generated if there are negative values in the scalar data but the filter continues. On a line-by-line basis in the GeneratePoints() method the scalar values are checked. If a line is found to have negative scalar values a warning is generated, the line is skipped, and GeneratePoints() returns 0.</FONT></P>
<P><FONT SIZE=2>I created this method because I have several types of data where I know the centerline of a tubular structure and I also know the exact radius at each point. This method would be useful anytime you have a centerline and radius values (e.g vascular networks).</FONT></P>
<P><FONT SIZE=2>I have put together a small web page with the modified source code, screen shots, sample data, and a sample script.</FONT>
<BR><FONT SIZE=2>Please check it out at ...</FONT>
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<P><FONT SIZE=2><A HREF="http://kermit.evergreen.edu/tubeFilter/" TARGET="_blank">http://kermit.evergreen.edu/tubeFilter/</A></FONT>
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<P><FONT SIZE=2>Sincerely,</FONT>
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<P><FONT SIZE=2>Michael Ficker</FONT>
<BR><FONT SIZE=2>Lab Manager / Lead Developer</FONT>
<BR><FONT SIZE=2>Scientific Database Laboratory</FONT>
<BR><FONT SIZE=2>The Evergreen State College</FONT>
<BR><FONT SIZE=2>Olympia, WA</FONT>
<BR><FONT SIZE=2>(360) 867-5943</FONT>
<BR><FONT SIZE=2>ficmic01@evergreen.edu</FONT>
<BR><FONT SIZE=2> </FONT>
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