[Mesa-users] Running an OpenGL application without a Graphics Card "off-screen"

[Brian Paul]

On 03/07/2013 03:47 PM, Patrick Donnelly wrote:
> On Thu, Mar 7, 2013 at 5:31 PM, Brian Paul<brianp at vmware.com>  wrote:
>> On 03/07/2013 02:09 PM, Patrick Donnelly wrote:
>>>
>>> Hi,
>>>
>>> I'd like to be able to run an OpenGL application on a machine without
>>> a physical graphics card and capture the video output. My
>>> understanding is that Mesa has facilities for this but I'm not sure
>>> how to do it. Is it actually possible and how?
>>
>>
>> "OSmesa".  See include/GL/osmesa.h  Build mesa with --enable-osmesa. Check
>> out the Mesa demos package's src/osdemos/ directory for examples.
>
> Do I have to rebuild the application? If so, is there any (even
> exotic) workaround?

So the app uses GLX?

I guess the one possibility in that case is to run a VNC X server, 
like Xvnc.  It's basically an X server that doesn't touch the graphics 
hardware.  The framebuffer is basically just a block of memory.  You 
can use any VNC viewer to view the Xvnc desktop where your app would 
be running.  There's various X utils for capturing the X desktop to a 
file.

-Brian