Hi,
I’m trying to produce an opengl graph (via h3->Draw(“glbox”) ). While it is possible to do a save in interactive mode, it doesn’t work in batch mode. The .png picture represents an empty canvas.
Is it a bug or a feature ? Is there any way to save graphs made that way ?
Cheers
Damir
It is not implemented. Whereas in interactive mode the picture is created from the image in the pad, in batch mode the output is created via a special driver : TImageDump (a bit like for PS).
[quote]Hi,
I’m trying to produce an opengl graph (via h3->Draw(“glbox”) ). While it is possible to do a save in interactive mode, it doesn’t work in batch mode. The .png picture represents an empty canvas.
Is it a bug or a feature ? Is there any way to save graphs made that way ?
Cheers
Damir[/quote]
Hi, Damir. AFAIK our OpenGL code does not work in off-screen mode. It can be done using Mesa specific extensions, but this will work (???) only with mesa.
Ok, so if I understand, there is no simple way to do it. Maybe an X11 server which is “off screen” ?
What is this “mesa” method ?
Cheers
Damir
Ah, good, thanks! I guess it would also work by starting Xvfb and then setting DISPLAY for ROOT.
Otherwise, yes, TGLViewer stuff uses GLX / WGL / AGL to create rendering contexts. I’m not even sure if there is a generic off-screen option that would work everywhere, there sure wasn’t 12 years back 
Cheers,
Matevz