[winswitch] How to use the Xdummy with Xpra?

[Heng Zhou]

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.