<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div><div><div class="h5"><div><p style="margin-bottom:12pt"><font face="Verdana" size="2"><span style="font-size:10pt;font-family:Verdana">Hello everybody,<br>
<br>
I have a vtkLineSource object L1. I apply a transformation with the
vtkTransformPolyDataFilter tpd.<br>
<br>
so... as L1 is defined by 2 points, I have a transform TT which defines the
TransformPolyDataFilter.<br>
So I need to retrieve those 2 points but after the transform, so I call:<br>
<br>
vtkSmartPointer<vtkLineSource> tmplineDir =
vtkLineSource::SafeDownCast(tpd->GetOutput());<br>
<br>
but the pointer it returns is NULL, causing of course a crash of the software.<br>
what am I missing? :)<br>
<br>
Many thanks.<br>
Giancarlo<br>
</span></font></p><p style="margin-bottom:12pt"><font face="Verdana" size="2"><span style="font-size:10pt;font-family:Verdana"><br></span></font></p></div></div></div></div></blockquote><div><br></div><div>You can't cast a polydata as a lineSource, which you are trying to do with </div>
<div><span class="Apple-style-span" style="font-family: Verdana; font-size: 16px; ">vtkLineSource::SafeDownCast(tpd->GetOutput());</span></div><div><span class="Apple-style-span" style="font-family: Verdana; font-size: 16px; "><br>
</span></div><div><span class="Apple-style-span" style="font-family: Verdana; font-size: 16px; ">The output of tpd is a polydata, so you'd want to do </span></div><div><span class="Apple-style-span" style="font-family: Verdana; font-size: 16px; "><span class="Apple-style-span" style="font-size: 16px; ">vtkSmartPointer<vtkPolyData> output = tpd->GetOutput();</span></span></div>
</div><br><div>~David</div>