[vtk-developers] Speeding up `import vtk`

[Utkarsh Ayachit]

JC,

I am not a huge fan of this option since the `vtk`package will not
provide a consistent interface based on how the package was imported.
It will make it impossible to write scripts that use `import vtk` and
work reliably. e..g say I have a module (outside VTK) that relies on
`import vtk` to have all necessary symbols. Now my script will fail,
if some other module that the user imported before importing my module
changed the nature of the `vtk` package. Thus, the only way to write
reliable scripts is to import internal modules as needed, and that
defeats the purpose.

The future config you envision could currently be easily provided by
factory or other singletons in VTK library itself that control the
default render window created, for example, and should indeed be
supported there since it's useful for C++ users of VTK too.

Utkarsh

On Fri, Dec 15, 2017 at 12:04 AM, Jean-Christophe Fillion-Robin
<jchris.fillionr at kitware.com> wrote:
> Hi Utkarsh,
>
> I would prefer to have a more generic way of configuring the import
> behavior.
>
> The idea would be to have two top-level packages:  vtk and vtkConfig
>
> To skip  loading of all module, you would do:
>
> -------------------
> import vtkConfig
> vtkConfig.VTK_MODULE_IMPORT = vtkConfig.EXPLICIT   #  Default would be
> vtkConfig.ALL.  Later we could also have vtkConfig.LAZY
>
> import vtk
> -------------------
>
> This would allow to keep things coherent for our user. Naming the package
> "vtkmodules" seem unconventional.
>
> It would also have the advantage of support addition of new option.
>
> For example:
>
> vtkConfig.RENDERING_METHOD = vtkConfig.OFFSCREEN  #  or vtkConfig.MESA, ....
>
> Jc
>
>
> On Tue, Dec 12, 2017 at 4:55 PM, Utkarsh Ayachit
> <utkarsh.ayachit at kitware.com> wrote:
>>
>> On Tue, Dec 12, 2017 at 3:18 PM, Ben Boeckel <ben.boeckel at kitware.com>
>> wrote:
>> > On Tue, Dec 12, 2017 at 15:06:15 -0500, Prabhu Ramachandran wrote:
>> >> Would `vtkm` be a shorter name rather than `vtkmodules`?
>> >
>> > `vtkm` is a different project already (though I don't know of its status
>> > with Python wrapping outside of the VTK filters which use it).
>>
>> Yea, alas `vtkm` won't be a good option.
>> _______________________________________________
>> Powered by www.kitware.com
>>
>> Visit other Kitware open-source projects at
>> http://www.kitware.com/opensource/opensource.html
>>
>> Search the list archives at: http://markmail.org/search/?q=vtk-developers
>>
>> Follow this link to subscribe/unsubscribe:
>> http://public.kitware.com/mailman/listinfo/vtk-developers
>>
>
>
>
> --
> +1 919 869 8849