[vtkusers] vtkModifiedBSPTree slicing

[edd cmaugo]

I want to do this because when you slice a vtkpolydata representing a
volume, depending on the quality of the model, the resulting slices are not
always closed.
I rely on heuristics to close them but I just saw this page that say that,
by using a BSP tree, the result of the slicing operation is guaranteed to
be closed.

http://www.me.mtu.edu/~rmdsouza/CSG_BSP.html

I just want to know if it's possible to make it with vtk classes.

--
Eddy

2012/3/22 Biddiscombe, John A. <biddisco at cscs.ch>

>  erratum. I should have written “to add an intersect with plane” – not
> line.****
>
> ** **
>
> seeing the question again, you ask about vtkCutter, so in theory you might
> want any ImplicitFunction. The same argument applies, but the
> implementation become slightly more involved as you would have to test each
> box against the function and not against a simple plane.****
>
> ** **
>
> JB****
>
> ** **
>
> *From:* vtkusers-bounces at vtk.org [mailto:vtkusers-bounces at vtk.org] *On
> Behalf Of *Biddiscombe, John A.
> *Sent:* 21 March 2012 17:12
> *To:* edd cmaugo; vtkusers at vtk.org
> *Subject:* Re: [vtkusers] vtkModifiedBSPTree slicing****
>
> ** **
>
> *>*Is it possible to slice a vtkModifiedBSPTree with a vtkCutter ?****
>
> Not without code changes. Why would you do this? You can slice a
> vtkDataSet with a cutter and that will give you much the same result.****
>
> ** **
>
> Do you have data already in the BSP tree? and you want to cut it faster?**
> **
>
> ** **
>
> If the answer is yes to both, then look at the BSP tree intersect with
> line code. I think in my local repo I may have an intersect with Box
> function too. To add an intersect with line, you need only walk the tree
> using the stack in the same way as the existing code, test each bounding
> box against the slice plane and reject any on the wrong side. open those
> that overlap and then keep going until you get to cells. Then you can call
> vtkCell intersect/slice or whatever.****
>
> It would be quite simple to implement if you examine the existing code.***
> *
>
> ** **
>
> JB****
>
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