Re: Advertised OpenGL version on IvyBridge

On Sun, 2013-02-17 at 00:48 -0600, Michael Cronenworth wrote:
> I heard on Phoronix that IvyBridge/SandyBridge hardware is supposed to 
> have OpenGL 3.0/3.1 support on Mesa 9.0 and 9.1. However, glxinfo is 
> telling me something different.
> 
> CPU: Core i3-3225 (HD4000)
> Distro: Fedora 18 x86_64
> OpenGL vendor string: Intel Open Source Technology Center
> OpenGL renderer string: Mesa DRI Intel(R) Ivybridge Desktop
> OpenGL version string: 2.1 Mesa 9.0.1
> OpenGL shading language version string: 1.30
> 
> Is this accurate or is Phoronix mistaken?

HD4000 does indeed support OpenGL 3.1.  However because of US patent
implications Fedora builds Mesa without --enable-texture-float
configure option and this disables OpenGL 3.0/3.1.  I'm not a lawyer
but AFAIK since it is not world-wide patent it is safe to use
--enable-texture-float if you are outside US, and some Linux distros
like Ubuntu do so by default.  Rebuilding Mesa from source RPM on
Fedora 18 with the named option enables OpenGL 3.1/shading 1.40 on my
HD3000.


-- 
  Tomash Brechko