Re: OpenGL on Linux

Hey Robinson,


On Wed, Jan 29, 2014 at 6:57 AM, Robinson Tryon
<bishop.robinson@gmail.com>wrote:

> On Sat, Jan 11, 2014 at 9:54 AM, Markus Mohrhard
> <markus.mohrhard@googlemail.com> wrote:
> > Could some of you please send me the output of glxinfo to provide a
> picture
> > which OpenGL versions are available and more importantly which OpenGL
> > extensions are supported?
>
> Does any distro keep track of this kind of information?  I know that
> there are some similar databases for hardware, etc.. out there, but
> not sure if they'd provide output from glxinfo...

It is a bit more complicated than that on Linux. On Linux you have two
factors that play a significant role. Mesa provides your basic OpenGL
support including the one for the open source drivers. As this is an
important package in most cases it is the default provided by your
distribution. It is well known which OpenGL version is supported by
different Mesa versions.

Now if you install the proprietary drivers it becomes more complex. The
driver supports normally a much newer OpenGL version. Basically I needed to
know if I can safely assume that everyone has support for OpenGL 3.0+.

So this was the easy part of the OpenGL problem. As you might have noticed
there are a lot more lines and they tell me even more. Basically OpenGL is
not a fixed API, instead everyone can implement new features that are added
through an extension mechanism to the API and are advertised by the driver
through these strings. Currently the code that we have written assumes that
some of these extensions are available and some others are supported but
not mandatory. All in all this gives me an idea what we can safely use in
the OpenGL code.

The picture becomes more complex with mobile platforms but I have left them
out for now.

For anyone interested the important things that I know are a bit more
critical and we use already(there is surely more but I don't know the
extension names):

GLSL 1.10+
GL_ARB_framebuffer_object
GLX_ARB_multisample (if available)
GL_ARB_multisample (if available)
GL_EXT_framebuffer_blit (I think we use it)

Regards,
Markus


> Attached is the output from my laptop w/NVIDIA driver installed.
>
> Cheers,
> --R