[vtkusers] volume calculation

[Karthik Krishnan]

2009/9/9 Murat Aydın <murat.aydin at netcad.com.tr>

>  Hi,
>
> I am calculating volume of solid constructed by vtkDelaunay3D applied to a
> point cloud.
>
> i am using vtkGeometryFilter -> vtkTriangleFilter -> vtkMassProperties in
> order to get volume of the solid.
>



> I am not sure whether the calculated volume is correct,
>

No issues AFAIK.


> because if i add
> vtkDecimatePro filter or vtkSmoothPolyDataFilter the volume changes.
>

It is certainly going to change a bit. The locations of the points
comprising the polydata are going to change due to smoothing and this is
going to impact the projected volume.


> Without vtkDecimatePro , the volume seems to be more than it should be.What
> should i do to find true volume? Thanks in advance.
>

How do you arrive at that conclusion. Please take a look at the paper
referenced in the header.

At most there may be numerical issues with computing the projected volume of
axis aligned triangles. The filter alleviates this by computing the volume
along the three axes and averaging them.



-- 
karthik
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