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                    Hi All,
                </div><div><br></div><div>I am trying to get the curvature information at the vertices of an edge. I have the following setup</div><div><br></div><div>
<pre style="margin-top: 0px; margin-bottom: 0px; "><!--StartFragment--><font color="#320dfe">// extract edges from the resulting curvature data</font></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">    </span>edge_extractor_<span style=" color:#aaaaaa;">-&gt;</span>SetInput<span style=" color:#aaaaaa;">(</span>curvatures_<span style=" color:#aaaaaa;">);</span></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">    </span>edge_extractor_<span style=" color:#aaaaaa;">-&gt;</span><span style=" font-style:italic;">Update</span><span style=" color:#aaaaaa;">();</span></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><font color="#c0c0c0"><br></font></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><font color="#320dfe">    // traverse all the edges to look for zero crossings</font></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">    </span><font color="#f9231b">for</font><span style=" color:#aaaaaa;">(</span><span style=" color:#55ff55;">vtkIdType</span><span style=" color:#c0c0c0;"> </span>i<span style=" color:#c0c0c0;"> </span><span style=" color:#aaaaaa;">=</span><span style=" color:#c0c0c0;"> </span><span style=" color:#ff55ff;">0</span><span style=" color:#aaaaaa;">;</span><span style=" color:#c0c0c0;"> </span>i<span style=" color:#c0c0c0;"> </span><span style=" color:#aaaaaa;">&lt;</span><span style=" color:#c0c0c0;"> </span>edge_extractor_<span style=" color:#aaaaaa;">-&gt;</span>GetOutput<span style=" color:#aaaaaa;">()-&gt;</span><span style=" font-style:italic;">GetNumberOfCells</span><span style=" color:#aaaaaa;">();</span><span style=" color:#c0c0c0;"> </span>i<span style=" color:#aaaaaa;">++)</span></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">    </span><span style=" color:#aaaaaa;">{</span></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">        </span><span style=" color:#55ff55;">vtkSmartPointer</span><span style=" color:#aaaaaa;">&lt;</span><span style=" color:#55ff55;">vtkLine</span><span style=" color:#aaaaaa;">&gt;</span><span style=" color:#c0c0c0;"> </span>edge_line<span style=" color:#c0c0c0;"> </span><span style=" color:#aaaaaa;">=</span><span style=" color:#c0c0c0;"> </span><span style=" color:#55ff55;">vtkLine</span><span style=" color:#aaaaaa;">::</span>SafeDownCast<span style=" color:#aaaaaa;">(</span>edge_extractor_<span style=" color:#aaaaaa;">-&gt;</span>GetOutput<span style=" color:#aaaaaa;">()-&gt;</span><span style=" font-style:italic;">GetCell</span><span style=" color:#aaaaaa;">(</span>i<span style=" color:#aaaaaa;">));</span></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><br></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><font color="#320dfe">        //todo, get the curvature and the vertices of this edge</font></pre>
<pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#c0c0c0;">    </span><span style=" color:#aaaaaa;">}</span><!--EndFragment--></pre><pre style="margin-top: 0px; margin-bottom: 0px; "><span style=" color:#aaaaaa;"><br></span></pre><pre style="margin-top: 0px; margin-bottom: 0px; "><font color="#aaaaaa"><br></font></pre><pre style="margin-top: 0px; margin-bottom: 0px; ">Where curvatures_ is PolyData that is the result of running gaussian curvature computation and edge_extractor is the simple ExtractEdge filter </pre><pre style="margin-top: 0px; margin-bottom: 0px; "><br></pre><pre style="margin-top: 0px; margin-bottom: 0px; ">How can I get the vertices of the edge I just got as a line? and how can I then lookup the curvature values at these vertices as I need to compare these.</pre><pre style="margin-top: 0px; margin-bottom: 0px; "><br></pre><pre style="margin-top: 0px; margin-bottom: 0px; ">Thanks</pre><pre style="margin-top: 0px; margin-bottom: 0px; "><br></pre><pre style="margin-top: 0px; margin-bottom: 0px; ">Bill</pre></div>