[vtkusers] Contouring through constant value areas of dataset

[David E DeMarle]

Ah, so presumably one of those isocontours happens to hit the
contoured value exactly and you expect the whole thing to be drawn but
it is not.

You can reproduce the behavior with any Source, using Calculator to
give every point the same constant scalar value, and then contouring
on that value.

You would expect everything to be drawn, but nothing is. I don't know
why it does that.

anyone?

On Fri, Sep 5, 2008 at 4:38 PM, Gerrick Bivins
<gbivins at objectreservoir.com> wrote:
> Right. But for instance, if I were visualizing this data via volume
> rendering, the areas with this constant value would be displayed rather than
> not.
> Am I misunderstanding the intent of contouring? If so, is there another
> filter I can use to accomplish what I'm describing?
> Gerrick
>
>
> On 9/5/08 3:29 PM, "David E DeMarle" <dave.demarle at kitware.com> wrote:
>
>> Umm, because the values are constant? Which means they contain only
>> one value, and thus either nowhere contain the value that a contour
>> displays, or everywhere contain it.
>>
>> I am not sure I understand your question otherwise.
>>
>>
>> On Fri, Sep 5, 2008 at 4:17 PM, Gerrick Bivins
>> <gbivins at objectreservoir.com> wrote:
>>>
>>> Hi All,
>>> When generating contour values (isosurfaces) with vtkContourFilter, I've
>>> noticed that areas in the dataset with constant values ( probably not the
>>> correct terminology here) don't produce contours.
>>>
>>> For example, here is the original multiblock dataset in Paraview with areas
>>> of constant value:
>>> http://www.nabble.com/file/p19338704/constantValues-surface.png
>>>
>>> Here is the contouring with about 100 values:
>>> http://www.nabble.com/file/p19338704/constantValues-100-contours.png
>>>
>>> Here is the contouring with ALOT of values:
>>> http://www.nabble.com/file/p19338704/constantValues-many-contours.png
>>>
>>> Can someone explain why the square area(bottom left of the elliptical
>>> dataset) and triangle area (bottom right) don't produce any contours? The
>>> only similarities are that the values in those areas are constant in those
>>> areas.
>>> Gerrick
>>>
>>>
>>> --
>>> View this message in context:
>>> http://www.nabble.com/Contouring-through-constant-value-areas-of-dataset-tp19
>>> 338704p19338704.html
>>> Sent from the VTK - Users mailing list archive at Nabble.com.
>>>
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>