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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Dear Users,<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>I found a problem when I used vtkImplicitPlaneWidget for cutting. I set the origin and normal for the planeWidget I defined. But when showing the result, I found that the arrow and the plane was not orthogonal. I could not understand why it happened. Here is my code:<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; vtkImplicitPlaneWidget *planeWidget = vtkImplicitPlaneWidget::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetInteractor(iren_SP);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetPlaceFactor(1.0);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetHandleSize(0.01);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetInput(iso_Liver-&gt;GetOutput());<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;PlaceWidget();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span style='color:green'><o:p></o:p></span></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetOrigin(Center); <span style='color:green'><o:p></o:p></span></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetNormal(n); <span style='color:green'><o:p></o:p></span></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetRepresentationToSurface();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;GetPlaneProperty()-&gt;SetColor(0.4,0.8,0.9);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;GetPlaneProperty()-&gt;SetOpacity(0.9);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span style='color:green'><o:p></o:p></span></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;AddObserver(vtkCommand::InteractionEvent,myCallback);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:NSimSun'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:NSimSun'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; planeWidget_SP-&gt;SetEnabled(1);<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:NSimSun'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal>Could anyone please check my code and tell me whether and where I made a mistake?<o:p></o:p></p><p class=MsoNormal><o:p>&nbsp;</o:p></p><p class=MsoNormal>Thanks a lot,<o:p></o:p></p><p class=MsoNormal>Xiaopeng<o:p></o:p></p></div></body></html>