[winswitch] How to use the Xdummy with Xpra?

[Antoine Martin]

On 27/12/14 22:45, Heng Zhou wrote:
> Hi,
>
> According to The webpage https://www.xpra.org/trac/wiki/Xdummy and
> http://en.wikipedia.org/wiki/Xvfb, my understanding is that, using "Xdummy
> with Xpra", we can run any program that produce graphical output on a
> computer that does not install any physical graphics card and physical
> screen, because the output of the program can be produced by Xdummy and
> transfered to my local computer through Xpra. It is true for OpenGL program
> in particular, assuming I have installed mesa in which a software
> simulation of OpenGL rasterization is implemented. Am I right? If I am, how
> can we run an OpenGL program, say, glxinfo or glmark2, on a remote machine
> that has no physical graphics card (so /dev/dri/card0 and /dev/fb0 do not
> exist as a result), e.g., the Amazon EC2 t2.micro instance running ubuntu
> 14.04, and transfer the output (the animation) back to my local computer? I
> can not grasp the idea of the example in the aforementioned Xdummy webpage,
> and searching the internet (for a couple of days already) did not gives me
> any useful hint. So could you please help me with this question? Thank you
> very much.
The default xpra installations using Xdummy support OpenGL as the Xorg
command line includes "+extension GLX".
Forwarding "glxgears" (or any other gl application) works fine out of
the box, if you have access to a real graphics card in the server system
you can also use VirtualGL to get hardware acceleration.

Unfortunately, Ubuntu does weird things with their Xorg server
installation and so you may not be able to use Xdummy on Ubuntu.

Cheers
Antoine