<div dir="ltr">Burlen,<div> Thankyou so much for your quick response. The script works fine. I am a bit of a ParaView novice when it comes to scripting so thanks for the help!</div><div><br></div><div>This problem arose because I was looking at the VTK Parametric Functions and wondering why they looked so terrible in ParaView and yet there were no issues displaying them in VTK. </div>
<div>So I wrote an XML plugin and discovered that I couldn't access the scalars or normals. In the case of normals, for non-orientable surfaces the normals become really important and they are generated with the surface, so you need access the data. Paraview can do this if it knows the name of the dataset.</div>
<div><br></div><div>It turns out that when I wrote vtkParametricFunctionSource (way back in 2003 I think!) I never named the normal or scalar arrays. So I will fix this, modernise the code and update the documentation in this coming week.</div>
<div><br></div><div>If you are interested, here is a first attempt at the xml plugin. With your script we get some beautiful results in Paraview. Of course I need to add in the parameters for all the other surfaces. I have only done ParametricConicSpiral and ParametricMobius.</div>
<div><br></div><div>First: Use Manage Plugins to import the xml script.</div><div>Then:</div><div>1) Find ParametricSource in Sources and select a function e.g Mobius, (Minimum V = -0.2, Maximum V = 0.2) specify a scalar mode and you will get a very ordinary mobius strip.</div>
<div>2) Apply your script as a programmable filter and select the coloring to be scalars and you get a beautifully shaded surface.</div><div>3) Then apply the Glyph filter using the Normals as vectors and you get a nice display of the vectors on the surface. Use a scale of (-1,-1,-1) if you want to invert the normals.</div>
<div><br></div><div>You get some beautiful images.</div><div><br></div><div>Regards</div><div> Andrew</div><div><br></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Sun, Jun 1, 2014 at 3:03 AM, Burlen Loring <span dir="ltr"><<a href="mailto:bloring@lbl.gov" target="_blank">bloring@lbl.gov</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
Hi Andrew,<br>
<br>
I see a couple of things in your script. First is normals and
scalars are data set attributes. so you need to access them through
one of those classes, ex vtkPointData. <br>
<br>
Correct me if I'm wrong but, although in VTK 6 you generally don't
need to shallow copy the input to filters I think it's still
probably a bad practice to modify the arrays in the input dataset. <br>
<br>
I think what you want to do is copy the geometric structure of the
input and then make a deep copy of normals and scalars arrays, and
rename the copys. Copy structure rather than shallow copy since with
a shallow copy you'd still end up modifying the arrays in the input
dataset.<br>
<br>
Finally scalars and normals may not be present. I know you'd
probably handle that in your final script, ;-)<br>
<br>
given all that, here's what I came up with:<br>
<blockquote>def copyAndNameArray(da, name):<br>
if da is not None:<br>
outda = da.NewInstance()<br>
outda.DeepCopy(da)<br>
outda.SetName(name)<br>
return outda<br>
else:<br>
return None<div class=""><br>
<br>
pdi = self.GetPolyDataInput()<br>
pdo = self.GetPolyDataOutput()<br></div>
pdo.CopyStructure(pdi)<br>
<br>
pdo.GetPointData().SetNormals( \<br>
copyAndNameArray(pdi.GetPointData().GetNormals(), 'Normals'))<br>
<br>
pdo.GetPointData().SetScalars( \<br>
copyAndNameArray(pdi.GetPointData().GetScalars(), 'Scalars'))<br>
<br>
print 'Normals=%s'%(str(pdo.GetPointData().GetNormals()))<br>
print 'Scalars=%s'%(str(pdo.GetPointData().GetScalars()))<br>
</blockquote>
Curious to hear from other developers as to if I'm on target about
not modifying arrays in the input or if this is overkill given the
new VTK 6 pipeline.<br>
<br>
Burlen<div><div class="h5"><br>
<br>
On 05/30/2014 07:29 PM, Andrew Maclean wrote:<br>
</div></div><blockquote type="cite"><div><div class="h5">
<div dir="ltr">I have a source object that produces a polydata
object. Unfortunately the normals and scalars are unnamed. How
do I access these and name them in ParaView.
<div>I thought something like this may work in a Programmable
Filter:</div>
<div>
<pre style="padding:0px;border:0px none white;color:rgb(0,0,0);line-height:1.2em;font-size:10px;margin-top:0px;margin-bottom:0px;vertical-align:top;background-image:none;background-repeat:initial"><p style="margin:0px">
pdi = self.GetPolyDataInput()</p>
<p style="margin:0px">pdo = self.GetPolyDataOutput()</p>
<p style="margin:0px">pdi.GetNormals().SetName('Normals')</p>
<p style="margin:0px">pdi.GetScalars().SetName('Scalars')</p>
<p style="margin:0px">pdo = pdi</p></pre>
<div><br>
</div>
<div>However, I can't see the array names.</div>
<div><br>
</div>
<div>This sort of thing works Ok in a Python Script:</div>
<div>
<div> # Name the arrays</div>
<div>
randomHillsSource.GetOutput().GetPointData().GetNormals().SetName('Normals')</div>
<div>
randomHillsSource.GetOutput().GetPointData().GetScalars().SetName('Scalars')</div>
<div># pd = randomHillsSource.GetOutput().GetPointData()</div>
<div># print pd</div>
</div>
<div><br>
</div>
<div>Is it possible to do this on ParaView?</div>
<div><br>
</div>
<div>Thanks in advance for any help.</div>
<div><br>
</div>
<div>Andrew</div>
<div><br>
</div>
-- <br>
___________________________________________<br>
Andrew J. P. Maclean<br>
<br>
___________________________________________
</div>
</div>
<br>
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<br>
</div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br>___________________________________________<br>Andrew J. P. Maclean<br><br>___________________________________________
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