[vtk-developers] Shared ownership of an array of pointers

[Philippe Pébay]

Hello David

Thanks for the suggestion: I am concerned by the overhead that comes with
variants. Wouldn't it be more lightweight to use a vtkVoidArray instead?
The array can potentially contain O(10⁶) pointers. By the way this is for
the same reason that I have, so far, refrained from using vtkSmartPointers
as opposed to raw pointers, by fear of the overhead involved. Is this extra
caution excessive?

Thanks
Philippe

On Tue, Nov 20, 2012 at 5:31 PM, David Gobbi <david.gobbi at gmail.com> wrote:

> Hi Philippe,
>
> If the pointers are pointers to VTK objects, then you can use
> vtkVariantArray.
>
>  - David
>
>
> On Tue, Nov 20, 2012 at 9:29 AM, Philippe Pébay
> <philippe.pebay at kitware.com> wrote:
> > Just an idea: couldn't a vtkVoidArray be used (or abused) as container of
> > raw pointers, that would be appropriately downcasted internally to the
> > concrete type to which they are supposed to point? For instance, instead
> of
> > having a
> >  vtkMyInternalObject** obj
> > instance variable, couldn't I use a
> >  vtkVoidArray* obj
> > instead, where each entry in obj would be the raw pointer to a
> > vtkSmartPointer<vtkMyInternalObject>?
> >
> > Thanks
> > Philippe
> >
> >
> > On Tue, Nov 20, 2012 at 5:14 PM, Philippe Pébay <
> philippe.pebay at kitware.com>
> > wrote:
> >>
> >> Hello Kyle
> >>
> >> Yes, I would want to avoid a dependency on Boost. But this is basically
> >> what I am tried to reproduce (the Boost shared array of pointers).
> >>
> >> Thanks
> >> P
> >>
> >>
> >> On Tue, Nov 20, 2012 at 5:13 PM, Kyle Lutz <kyle.lutz at kitware.com>
> wrote:
> >>>
> >>> Would using boost suffice? Or do you want a solution using just VTK?
> >>>
> >>> -kyle
> >>>
> >>> On Tue, Nov 20, 2012 at 7:58 AM, Philippe Pébay
> >>> <philippe.pebay at kitware.com> wrote:
> >>> > Hello all,
> >>> >
> >>> > I need to keep track of shared ownership of an array of pointers. Can
> >>> > someone point me towards an example of code that already does this?
> >>> > This
> >>> > should amount to a small helper class that contains the array of
> >>> > pointers
> >>> > along with a reference count.
> >>> >
> >>> > Thank you!
> >>> > Philippe
> >>> >
> >>> >
> >>> > --
> >>> > Philippe Pébay, PhD
> >>> > Director of Visualization and High Performance Computing /
> >>> > Directeur de la Visualisation et du Calcul Haute Performance
> >>> > Kitware SAS
> >>> > 26 rue Louis Guérin, 69100 Villeurbanne, France
> >>> > +33 (0) 6.83.61.55.70 / 4.37.45.04.15
> >>> > http://www.kitware.fr
>



-- 
Philippe Pébay, PhD
Director of Visualization and High Performance Computing /
Directeur de la Visualisation et du Calcul Haute Performance
Kitware SAS
26 rue Louis Guérin, 69100 Villeurbanne, France
+33 (0) 6.83.61.55.70 / 4.37.45.04.15
http://www.kitware.fr <http://www.kitware.fr/>
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