Re: Help needed to update our use of OpenGL

[John W. Eaton]

On 09/12/2018 11:21 AM, mmuetzel wrote:
> What needs to be changed with the way lighting is handled?
> I am by no means an expert in OpenGL. But I don't remember using deprecated
> functions when I added the light graphic object.
> If you could point to the problematic functions or constructs, I might be
> able to have a look at it.
>
> If someone else wants to help or prefer to do that, I won't mind either. ;-)

To begin, see this page:

  https://www.khronos.org/opengl/wiki/Legacy_OpenGL

also this page specifically about lighting notes that the fixed-pipeline 
glMaterial and glLight functions are part of the legacy APIs:

  https://www.khronos.org/opengl/wiki/How_lighting_works

Here's a interesting blog post about the difficulty (or not, depending 
on the specific features used) of moving to current core OpenGL 
functionality:

  https://retokoradi.com/2014/03/30/opengl-transition-to-core-profile/

From what I see with Octave, it looks like we have some work to do. 
OTOH, our use of OpenGL is fairly localized and does not seem overly 
complicated, so maybe it will not be an impossible task.

jwe