[vtk-developers] vtkBandedPolyDataContourFilter seems wrong, and also not compatable with vtkContourFilter

[Bill Lorensen]

Upon further investigation I see that the BandedPolyDataContourFilter
algorithm works fine with triangles. It seems to have trouble with
polygons and quads.

If your real dataset has triangles or can be triangulated, then you
should use BandedPolyDataContourFilter  rather than my technique that
uses multiple Clipper's. The results will be identical, and the
BandedPolyDataContourFilter  is probably more efficient.

Bill

On Fri, Jan 15, 2010 at 10:57 AM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
> Try the attached. It will not produce the exact output you see in
> matlab because it uses a different algorithm.
>
> Try it on you real data. I'll clean it up when I get a chance and post
> it on the wiki
>
> Bill
>
> On Fri, Jan 15, 2010 at 12:36 AM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>> I don't think there is a vtk filter that will do what you want.
>> BandedPolyData uses a different algorithm than the contour filters.
>>
>> However, I think the same affect can be achieved with mulitple
>> ClipPolyData's. I'll see if I can come up with an example to
>> illustrate this.
>>
>> Maybe over the weeked,
>>
>> Bill
>>
>> On Thu, Jan 14, 2010 at 10:22 PM, Junjie Cao <jjcao1231 at gmail.com> wrote:
>>> Dear Bill and vtk-developers,
>>> Thanks for your reply. vtkQuad works better.
>>> But in fact I've a bigger and smoother data and the output of
>>> vtkBandedPolyDataContourFilter seems bad.
>>> While I need the effect of Banded Contour not only some contour curves.
>>> Is there some filter for this? Or Is there any development plan to correct
>>> this?
>>> Or I've to use discrete color to display the scalars on the grid directly?
>>> Best wishes,
>>> JJCAO
>>>
>>
>