Re: Running an OpenGL application without a Graphics Card "off-screen"

On 03/07/2013 04:01 PM, Brian Paul wrote:
> On 03/07/2013 03:47 PM, Patrick Donnelly wrote:
>> On Thu, Mar 7, 2013 at 5:31 PM, Brian Paul<[email protected]> 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.

Oh, and build Mesa with --enable-xlib-glx --disable-driglx-direct 
--disable-dri so that you get an Xlib-based swrast driver.

-Brian