[vtk-developers] VTK Modularization

[Bill Lorensen]

Marcus,

That sounds good. I just wanted to make sure that both teams VTK/ITK
have been communicating. I thought they were and it seems they are. I
just misunderstood your initial comments.

Bill

On Sat, Feb 19, 2011 at 2:44 PM, Marcus D. Hanwell
<marcus.hanwell at kitware.com> wrote:
> Bill,
>
> I think you should give us a chance to outline what will be done
> before worrying too much. What makes you think that we will not take
> input from the community? I already said we would follow the patterns
> in ITK that make sense for VTK, and there will certainly be time for
> you and other members of the community to comment on proposed changes.
>
> You would have to be more specific about what differences you feel
> would cause problems before I could even comment. I already posted to
> the list stating that we would be seeking input once work began, and
> already stated that I am working closely with the ITK team. What more
> do you want to be done at this early stage?
>
> Marcus
>
> On Sat, Feb 19, 2011 at 2:39 PM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>> Marcus,
>>
>> I hope the VTK developers can work with the Kitware ITK modularization
>> team and come to some common ground. I was under the impression that
>> that was the case. They are getting ready to deploy the ITK
>> modularization within the next few weeks. The ITK developers have had
>> a lot discussion on this topic and the Modularization team has been
>> very good at taking in the inputs of the community.
>>
>> If the ITK and VTK modularizations are not similar, then we have a real problem.
>>
>> Bill
>>
>> On Sat, Feb 19, 2011 at 2:33 PM, Marcus D. Hanwell
>> <marcus.hanwell at kitware.com> wrote:
>>> Bill,
>>>
>>> On Sat, Feb 19, 2011 at 2:29 PM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>>>> Marcus,
>>>>
>>>> We might consider adding VTK_LIBRARIES now to ease the transition later.
>>>
>>> Ah, I see what you mean. There are a few possibilities I wanted to
>>> look at with exported targets to ease the transition too.
>>>>
>>>> Also, when you say you are not following the ITK modularization does
>>>> that mean you will not be following its pattern, or that you are not
>>>> monitoring it. I hope you mean the latter.
>>>
>>> I have followed the ITK and Boost modularization efforts, doing some
>>> work on the Boost build system. I meant that we are not necessarily
>>> following the exact same pattern, but that we would certainly be
>>> reusing code and patterns that work best for the VTK project. Is that
>>> clearer?
>>>
>>> I have been traveling a lot the last two weeks, but I think we will be
>>> meeting to talk more about this and set out likely timelines sometime
>>> next week.
>>>
>>> Marcus
>>>>
>>>> On Sat, Feb 19, 2011 at 2:23 PM, Marcus D. Hanwell
>>>> <marcus.hanwell at kitware.com> wrote:
>>>>> On Sat, Feb 19, 2011 at 2:10 PM, Bill Lorensen <bill.lorensen at gmail.com> wrote:
>>>>>> Folks,
>>>>>>
>>>>>> Just a heads-up on some things to expect when VTK is modularized.
>>>>>>
>>>>>> ITKv4 has a modularization effort led by Kitware. As part of this, the
>>>>>> ITK code layout will change accordingly. The work is described here:
>>>>>> http://www.vtk.org/Wiki/ITK_Release_4/Modularization
>>>>>>
>>>>>> For ITK, we will go from about a dozen code directories to over 80
>>>>>> directories. This will result in over 40 libraries.
>>>>>>
>>>>>> For the most part, applications are agnostic regarding source tree
>>>>>> layout. The include directories are handled by cmake. However, the
>>>>>> library specification in CMakeLists.txt can  cause issues.
>>>>>>
>>>>>> The good news, for ITK, is that we have always had a cmake variable
>>>>>> called ITK_LIBRARIES. This  meant to be used by applications in
>>>>>> target_link_libraries rather than listing specific libraries.
>>>>>> The bad news, for ITK, is that hardly anyone ever used ITK_LIBRARIES.
>>>>>> The good news is that current ITK applications can start using
>>>>>> ITK_LIBRARIES within their ITK3 applications and avoid work when the
>>>>>> move to the modularized ITK4.
>>>>>>
>>>>>> VTK does not have a VTK_LIBRARIES at least as far as I know.
>>>>>>
>>>>> We are not following the ITK modularization, but will be sharing code
>>>>> etc where appropriate. Quite a few projects I use (such as Boost and
>>>>> Qt) also use the PROJECTNAME_LIBRARIES variable approach, and I think
>>>>> this would be a great pattern to add to VTK too. It should make
>>>>> handling more libraries in VTK simpler for application developers too.
>>>>>
>>>>> Marcus
>>>>>
>>>>
>>>
>>
>