[vtkusers] Questions on Boolean Ops & vtkPolyData merging

[Jean-Marie Normand]

Hi all!

I am new to VTK, and  I'm trying to use vtk to perform boolean
operations on polyData, it seems to be possible by using
vtkImplicitDataSet but I haven't been able to use it properly and I
haven't found many examples of it. 

I've searched in the archives of the mailing list and I saw that David
Pont had written a vtkImplicitPolyData class that could handle what I'd
like to do. I would be very glad if he (or someone else ;) could provide
me the code of this class and even better some examples on how to use
it.

Moreover since I failed using vtkImplicitDataSet, I tested the boolean
ops on some ImplicitFunctions, which worked very well, but I have a
question about the visualization of the resulting surfaces. Once I get
the implicit boolean, I declare a vtkSampleFunction which I think (but I
may be wrong) represent the distance function of the implicit function
nd afterwards I need a vtkContourFilter which will represent the
polgonal surface (I still may be wrong). 

My question is what does the vtkContourFilter::SetValue actually do, I
don't really understand what does the 2nd parameter represent, I know
this question may seems dumb but I'm not used working on Implicit
Functions, I usually work on volumic surfaces and polygonal datas.


I also wonder if it is possible to merge the geometry/topology of 2
vtkPolyData objects, I saw the vtkMergeFilter in the doc, but it seems
that you could only merge the geometry of one DataSet with the Scalars
or normals of antoher, but not with the geometry. I again may be wrong
since I'm really new to VTK.

I could provide further information if my questions are not clear
enough, any help would be greatly appreciated.
Thanks in advance.

Jim