Re: OpenGL in Ada

[Vadim Godunko <vgodunko@gmail.com>]

On Oct 9, 12:42 am, Yves Bailly <yves.bai...@gmail.com> wrote:
>
> Actually, I don't think it's enough, because different drivers and
> hardwares
> provide different OpenGL coverage. For example, maybe you can use
> pragma import(C, "glGenFramebuffers") with an OpenGL lib providing
> at least OpenGL 3, but it will fail if the lib provides only an older
> version.
> What is an extension in a given GL version may not be in another.
>
> The use of  a GetProcAddress function allows to work in any case,
> just some subprogram pointers stay null. Note that it's the only
> dependency imported from SDL, it could be replaced by a hand-
> written equivalent, therefore removing the dependency (I'm just too
> lazy for this). To be able to use "pragma import" in any case would
> require to link with something like Glew.
>
Another option can be generation of set of checks to detect
availability of features/extensions at configuration time and
generation of supported subset only (or preprocessing of generated
code).

> That said, remains the question of the creation of the GL context,
> the handling of events and so on, much things very system-dependent.
> As far as I know, GLUT is just too old for this, e.g. it doesn't
> handle
> Unicode at all. But I guess that's another story.
>
It is another story definitely. GtkAda and QtAda both provide all
needed functionality in cross-platform way.