Render WebGL in Xfvb - webgl

Question

I want to headless test WebGL code using Xvfb. Does anybody know how to do that?
I have 2 machines - both running Ubuntu. One with NVidia card and one with ATI:
The NVidia machine:
ipmi:~ $>xvfb-run glxinfo
name of display: :455
display: :455 screen: 0
direct rendering: No (If you want to find out why, try setting LIBGL_DEBUG=verbose)
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
GLX_ARB_multisample, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_OML_swap_method,
GLX_SGI_make_current_read, GLX_SGIS_multisample, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_MESA_copy_sub_buffer, GLX_INTEL_swap_event
client glx vendor string: NVIDIA Corporation
client glx version string: 1.4
...
ipmi:~ $>xvfb-run glxgears
3725 frames in 5.0 seconds = 741.884 FPS
3840 frames in 5.0 seconds = 767.310 FPS
4080 frames in 5.0 seconds = 814.811 FPS
4120 frames in 5.0 seconds = 821.859 FPS
The ATI machine:
shaka:~ $>xvfb-run glxinfo
name of display: :99
display: :99 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4
server glx extensions:
GLX_ARB_multisample, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_OML_swap_method,
GLX_SGI_make_current_read, GLX_SGIS_multisample, GLX_SGIX_fbconfig,
GLX_SGIX_pbuffer, GLX_MESA_copy_sub_buffer, GLX_INTEL_swap_event
client glx vendor string: Mesa Project and SGI
client glx version string: 1.4
shaka:~ $>xvfb-run glxgears
4326 frames in 5.0 seconds = 865.095 FPS
4343 frames in 5.0 seconds = 868.540 FPS
Even if shaka supports direct rendering using Mesa, I can't get a WebGL context.
Thanks!

Answer 1

With modern X11, you would be better off ignoring Xvfb and using the dummy display driver. See the "Additional notes" at http://www.x.org/wiki/XorgTesting for information about using it (you would presumably specify a custom xorg.conf with the necessary Device section). http://www.karlrunge.com/x11vnc/Xdummy is another way to use the dummy driver.