How to avoid this Xvfb error: ES2 Prism: Error - GLX extension is not supported

[Antoine Martin]

On 12/12/16 20:37, Roland Mainz wrote:
> On Mon, Dec 12, 2016 at 8:27 PM, Antoine Martin <antoine at nagafix.co.uk> wrote:
>> On 12/12/16 19:51, Long Vu wrote:
>>> On Mon, Dec 12, 2016 at 1:06 PM, Long Vu <long.vu at intelerad.com> wrote:
>>>> On Mon, Dec 12, 2016 at 12:20 PM, Adam Jackson <ajax at nwnk.net> wrote:
>>>>> On Mon, 2016-12-12 at 12:13 -0500, Long Vu wrote:
>>>>>
>>>>>> Would it be this xvfb-run option ?
>>>>>>
>>>>>> -s ARGS   --server-args=ARGS        arguments (other than server number and
>>>>>>                                     "-nolisten tcp") to pass to the Xvfb server
>>>>>>                                     (default: "-screen 0 640x480x8")
>>>>>>
>>>>>> I am not familiar with X server options, what server args I would need
>>>>>> to get rid of this "ES2 Prism: Error - GLX extension is not supported"
>>>>>> error?
>>>>>
>>>>> Yes, I think it would be:
>>>>>
>>>>> xvfb-run -s "-screen 0 640x480x24" # ... whatever else you use
>>>>
>>>> I tried xvfb-run -s "-screen 0 640x480x24", still the same error.  Any
>>>> other clues?
>>>>
>>>> ES2 Prism: Error - GLX extension is not supported
>>>>     GLX version 1.3 or higher is required
>>>> Xlib:  extension "RANDR" missing on display ":99".
>>>>
>>>>
>>>> Now that I run at 24 bpp, maybe I should force GLX to be enabled?  Or
>>>> have to specify a GLX version, otherwise the default is less than 1.3?
>>>>
>>>
>>> I bumped the resolution and manually try to enable GLX, still the same error.
>>>
>>> xvfb-run -s '-screen 0 1024x768x24 +extension GLX +iglx' <command>
>>>
>>> I don't know what else to try.
>> Your Xvfb on CentOS will not support the GL extension.
>> If you really must use OpenGL with your client applications:
>> 1) Use Xdummy
>> https://xpra.org/trac/wiki/Xdummy
>> 2) Use VirtualGL
>> http://www.virtualgl.org/
> 
> Correction:
> The version of Xvfb he is using has been compiled without GLX support
> and he "just" needs to recompile his own version with GLX support
> enabled...
For most people, using a different command line (Xdummy's or virtualgl
instead of Xvfb) will be a lot easier than recompiling the X11 server.
Especially for managing multiple deployments or handling system updates.

Cheers
Antoine

> ----
> 
> Bye,
> Roland
>