[vtkusers] [Fwd: Re: Smoothing polygons (vtkPolyData)]

[Bryn Lloyd]

This is unexpected, considering the documentation of the 
vtkDecimatePolylineFilter.

Do you have several polygons, or one large one?

I guess vtkDecimatePolylineFilter expects PolyLines (one cell with many 
points).

vtkDecimatePro expects triangles. If you have Polygons, you could 
convert them (split them) into triangles first using the
	vtkDataSetTriangleFilter
and then run a decimation filter on the result.

Cheers
Bryn



Oliver Rudolph wrote:
> Hi Bryn,
> 
> when I applied that filter, the number of points even grew and my closed
> polys vanished. Instead I had a flat rectangular surface of the size of
> the boundaries.
> 
> Yours,
> Oliver
> 
> 
> Bryn Lloyd wrote:
>> Hi Oliver,
>>
>> This filter, I think should do the job: vtkDecimatePolylineFilter
>>
>> http://www.vtk.org/doc/nightly/html/classvtkDecimatePolylineFilter.html
>>
>> -Bryn
>>
>>
>> Oliver Rudolph wrote:
>>> Dear all!
>>>
>>> Is there anything available in vtk that I simply haven't found yet for
>>> smoothing some polygonal data?
>>>
>>> I have a closed polygon in 3D space (although it's actually located on a
>>> plane) which is stored as vtkPolyData. Unfortunately, it consists of
>>> quite a lot of points, even in regions of low curvature. Is there any
>>> filter that can remove some of the points automagically?
>>>
>>> Best regards,
>>> Oliver
>>>
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> 
> 


-- 
-------------------------------------------------
Bryn Lloyd
Computer Vision Laboratory
ETH Zürich, Sternwartstrasse 7, ETF C110
CH - 8092 Zürich, Switzerland
Tel: +41 44 63 26668
Fax: +41 44 63 21199
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