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</o:shapelayout></xml><![endif]--></head><body lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi David,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>It works perfectly </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>!!<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks a lot!<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Paulo<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=PT style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De:</span></b><span lang=PT style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> David Doria [mailto:daviddoria@gmail.com] <br><b>Enviada:</b> quarta-feira, 15 de Fevereiro de 2012 23:09<br><b>Para:</b> Paulo José Correia Bernardes<br><b>Cc:</b> vtkusers@vtk.org<br><b>Assunto:</b> Re: [vtkusers] How to correctly represent a polygon<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>2012/2/15 Paulo José Correia Bernardes <<a href="mailto:pbernardes@uaum.uminho.pt">pbernardes@uaum.uminho.pt</a>><o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=PT>Hi,<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=PT> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>I’m a very inexperienced VTK-user and I’m facing a small problem.</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>I’m trying to represent an arbitrary polygon using VTKPolygon. First, I read the 3D points from a .xyz file (each line is a 3D point). The points are stored in an instance of vtkPoints and afterwards the polygon is constructed using VTKPolygon.</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>However, the resulting polygon has some “strange” rendering effects, as you can see in the attached jpg-file.</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Can someone please explain me what I’m probably doing wrong and the correct steps I should take?</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Thank you very much!</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Yours,</span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US> </span><span lang=PT><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Paulo</span><span lang=PT><o:p></o:p></span></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>OpenGL does not deal well with polygons that have points that are not exactly coplanar. You could add this polygon to a vtkPolyData and then use the vtkTriangleFilter to triangulate the polygon so that OpenGL handles it better.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Let us know if that helps.<br><br>David<o:p></o:p></p></div></div></body></html>