[Paraview] vtkContourFilter generates two contours when requesting only one

[Moreland, Kenneth]

I don't recall ever seeing anything of that nature with the contour filter.  Perhaps something is going wrong with the surface reconstruction algorithm.  I have not played with it a lot, but the artifacts you describe sound like those that could be generated if the surface reconstruction does not generate consistent normals.

It might be helpful to see your data.  Is there any way you could post it?

-Ken

________________________________
From: paraview-bounces at paraview.org [mailto:paraview-bounces at paraview.org] On Behalf Of Chris Cameron
Sent: Monday, August 25, 2008 8:49 AM
To: paraview at paraview.org
Subject: [Paraview] vtkContourFilter generates two contours when requesting only one

Hello,

I'm using Paraview off cvs somewhere between 3.3 and the latest head.

I have an Image (Uniform Rectilinear Grid) of 334170 cells and 349600 points. I have a point Data Array called "Distance" which was obtained using a surface reconstruction algorithm. I ran the Filters->Common->Contour on the Image Data and asked for an Isosurface at value 0 for "Distance".

The output I get is both that contour that looks correct at distance 0, and a second contour that is decidedly less accurate (very blocky looking) that 'wraps' the correct contour. In other cases I have had the opposite happen, that is, the correct contour wraps the less accurate contour.

Is this the intended output? I expected to only receive one contour if I only put in one value for Isosurface.

Thank You,

--
Chris Cameron
Mirarco Mining Innovation - e2vo
705-675-1151
x5113
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