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Hi guys,<br><br>I found I have a difficult to understand the text file generated by vtkPolyDataWriter.<br><br>The situation is I create a set of following 5 points to construct a ploygon:<br><br>vtkPoints *points = vtkPoints::New();<br> points->InsertPoint(0,0,0,0);<br> points->InsertPoint(1,2,2,0);<br> points->InsertPoint(2,4,2,0);<br> points->InsertPoint(3,6,0,0);<br> points->InsertPoint(4,3,1,0);<br>vtkCellArray *polys = vtkCellArray::New();<br> polys->InsertNextCell(5);<br> polys->InsertCellPoint(4);<br> polys->InsertCellPoint(3);<br> polys->InsertCellPoint(2);<br> polys->InsertCellPoint(1);<br> polys->InsertCellPoint(0);<br><br>Then, i performed the constrained Delaunay triangulation:<br>vtkPolyData *polyData = vtkPolyData::New();<br> polyData->SetPoints(points);<br> polyData->SetPolys(polys);<br>vtkDelaunay2D *del = vtkDelaunay2D::New();<br> del->SetInput(polyData);<br> del->SetSource(polyData);<br><br>At last, I tried to see the result of the triangulation by get the output and write the result polygon to a text file by using vtkPolyDataWriter <br><br>vtkPolyData * outputPolyData = del->GetOutput();<br> outputPolyData->Update();<br> vtkPolyDataWriter *writer = vtkPolyDataWriter::New();<br> writer->SetInput(outputPolyData);<br> writer->SetFileName("test.txt");<br> writer->Write();<br><br>The result text file is pretty confusing me:<br>----text.txt----------------------------------------<br># vtk DataFile Version 3.0<br>vtk output<br>ASCII<br>DATASET POLYDATA<br>POINTS 5 float<br>0 0 0 2 2 0 4 2 0 <br>6 0 0 3 1 0 <br>POLYGONS 3 12<br>3 4 2 1 <br>3 4 3 2 <br>3 4 1 0 <br><br>CELL_DATA 3<br>POINT_DATA 5<br>------------------------------------------------------<br>I can see the "POINTS 5 float" section is state the coordinate of 5 points<br>but the "POLYGONS 3 12" really confused me. Can any1 explain it for me PLZ!!!!!!!!!<br><br>Cheers! <br><br><div><font color="#000066"><font face="Verdana, Geneva, Arial, Sans-serif"><font size="2"><u>YANG</u> Rong <br></font><br>20 Orton,</font></font></div>
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