Linux OpenGL ABI discussion

[Alan Cox]

On Iau, 2005-09-29 at 09:49 +0200, Christoph Hellwig wrote:
> On Wed, Sep 28, 2005 at 04:07:56PM -0700, Andy Ritger wrote:
> > Some of the topics raised include:
> > 
> >     - minimum OpenGL version required by libGL
> >     - SONAME change to libGL
> >     - libGL installation path
> 
> I think the single most important point is to explicitly disallow
> vendor-supplied libGL binaries in the LSB.  Every other LSB componenet
> relies on a single backing implementation for a reason, and in practic

That is not actually true. It defines a set of API and ABI behaviours
which are generally based on a single existing common implementation.

> the Nvidia libGL just causes endless pain where people acceidentally
> link against it.  The DRI libGL should be declare the one and official
> one, and people who need extended features over it that aren't in the
> driver-specific backend will need to contribute them back.

If the LSB standard deals with libGL API/ABI interfaces then any
application using other interfaces/feature set items would not be LSB
compliant. Educating users to link with the base libGL is an education
problem not directly inside the LSB remit beyond the LSB test tools.

In addition the way GL extensions work mean its fairly sane for an
application to ask for extensions and continue using different
approaches if they are not available. In fact this is done anyway for
hardware reasons. There is a lack of "is XYZ accelerated" as an API but
that is an upstream flaw.

Alan