NVIDIA Is Still Pushing For A New Linux OpenGL ABI

[phoronix]

Phoronix: NVIDIA Is Still Pushing For A New Linux OpenGL ABI

Besides going over their Mir/Wayland support plans, NVIDIA's Andy Ritger also provided the latest update concerning their work to push a new OpenGL ABI on Linux. This new Linux OpenGL ABI has been talked about every year since 2012 but it's still not yet fully materialized...

http://www.phoronix.com/vr.php?view=MTgxMDk

[Ancurio]

Very nice work. This probably explains why GetProcAddress return values on Windows are context specific, seems like they figured out multi vendor GL there years ago.
Also, this makes me wonder if applications that call manually retrieved function addresses could gain a bit of speed as they would get the post-dispatch vendor-specific addresses instead of the neutral dispatch library ones.

[blackout23]

This is going to also improve the hybrid graphics support, I guess?

[computerquip]

Very nice work. This probably explains why GetProcAddress return values on Windows are context specific, seems like they figured out multi vendor GL there years ago.
Also, this makes me wonder if applications that call manually retrieved function addresses could gain a bit of speed as they would get the post-dispatch vendor-specific addresses instead of the neutral dispatch library ones.

There's glXGetProcAddress too... which has been there for years.

[Ancurio]

There's glXGetProcAddress too... which has been there for years.

Not sure what you mean? Of course glxGetProcAddress is there, otherwise it would be impossible to retrieve any entrypoints on X11. I don't see how that's related to what I wrote though.

[computerquip]

Because it returns a potentially context-specific function.
Also, glXGetProcAddress is not the only way to fetch a function pointer for OpenGL. Linux and Mac both allow you to use libdl.

[Ancurio]

Because it returns a potentially context-specific function.
Also, glXGetProcAddress is not the only way to fetch a function pointer for OpenGL. Linux and Mac both allow you to use libdl.

I'm pretty sure glXGetProcAddress doesn't return context specific adressess, do you have a source for that? I think the vendor provided libGLs are just plain implementations with no redirection. With Mesa, you always get a valid address to their jump table entry even if the OpenGL functionality isn't implemented (which is why it's an error to rely on GetProcAddress returning 0, always need to check the extension string).

[computerquip]

Woops, I had it backwards. Checking the specification states quite explicitly the exact opposite of what I said. I should know better...