[Mesa-users] OSMesa and GLSL

[Brian Paul]

On 07/18/2016 06:50 AM, Yury Voronov wrote:
> Hello,
>
> I am quite new to Mesa, so would someone please help me understand the things?
>
> I have some code for texture processing working on real GPUs that
> extensively use shader
> features. Now I'd like to put it on a back-end server with no display
> (or even video card).
> And I am going to use Off-Screen Mesa for this. The latest release
> 12.0.1 claimed to support
> OpenGL 4.3 - so I supposed GLSL 4.3 is also supported. However,
> Shading Language Support
> page states that only version 3.30 is supported.
>
> In the same time, when I compiled and linked the latest Mesa package
> with --enable-osmesa
> and --with-gallium-drivers=swrast (and DRI and GLX and EGL turned
> off), I have just GLSL v1.50
> support. No 4.00, not even 3.30! When I tried to use MESA_GLSL_VERSION_OVERRIDE,
> I've got 3.00 ES and that's it.
>
> So what should I use or how should I compile OSMesa in order to get
> support of GLSL v4.00
> or at least v3.30 ?

Different drivers support different versions of OpenGL.

OSMesa w/ llvmpipe/softpipe should support up to GL 3.3 / GLSL 3.30 
(IIRC).  But you have to use the new OSMesaCreateContextAttribs() 
function to get a core profile context.

-Brian