[vtkusers] Building VTK without OpenGL

[Marcus D. Hanwell]

On Wed, Oct 21, 2015 at 5:03 PM, Moreland, Kenneth <kmorel at sandia.gov> wrote:
> Thanks for everyone's help. I got this working now.
>
> As Bill and David suggested, I had to change VTK_RENDERING_BACKGROUND to
> OpenGL or OpenGL2. However, I don't understand why None is even provided
> as an option if it is not supported.

This did work when I added it, but I guess the dashboard that tested
it was lost, and it was broken at some point. I agree with you that it
should be removed (or fixed, and tested).
>
> Anyway, doing that caused an error about not finding OpenGL (because there
> is none on my system). The solution is to first turn off all VTK_Group_*
> options and configure again. At this point you get an error about all
> modules being off, but when using the GUI this step is necessary because
> the majority of the Module_* options do not show up until this point. Once
> I've done that I can flip on the appropriate modules.
>
> That said, I expect Bill's suggestion of running CMake with command line
> arguments setting the Module variables on should work just fine. Of
> course, that would mean I would know the right variables beforehand, which
> I don't. I just muddle along with the GUI because I is not a
> sophistimacated user.
>
We should make this simpler, and ensure we have a dashboard taking
this simple path to ensure it continues to work in the future.

Marcus