From ripley at stats.ox.ac.uk  Mon Jun 18 05:50:53 2007
From: ripley at stats.ox.ac.uk (Prof Brian Ripley)
Date: Mon, 18 Jun 2007 04:50:53 +0100 (BST)
Subject: [Rd] X11 help please
In-Reply-To: <46759924.5020103@stats.uwo.ca>
References: <46759924.5020103@stats.uwo.ca>
Message-ID: <Pine.LNX.4.64.0706180419440.7264@gannet.stats.ox.ac.uk>

rgl normally works under Xvfb on Linux: we've been using that for the 
testing 'for ever'.

However R should not 'crash' on an error in a package, and the X11 device 
has error handlers set up by

 	XSetErrorHandler(R_X11Err);
 	XSetIOErrorHandler(R_X11IOErr);

I don't see anything comparable in rgl.

The error seems to be in the attributes, so I would have a closer look at 
those.  In particular, how are you running Xvfb?: you may need something 
like

Xvfb :5 -screen 0 1280x1024x24 &
setenv DISPLAY :5

to ensure that you have a reasonable visual and hence colormap.
(On my system the default is 12 bit.)


On Sun, 17 Jun 2007, Duncan Murdoch wrote:

> The rgl package currently crashes R when running under Xvfb (the
> "virtual frame buffer" server), at least on MacOSX.  It makes sense that
> it shouldn't be able to work there (it needs interactivity), but I don't
> know how to detect the problems before they cause the crash.
>
> Currently the error happens the first time you try to open an rgl
> window; when rgl calls XCreateWindow R crashes with the error message
>
> X Error of failed request:  BadMatch (invalid parameter attributes)
>  Major opcode of failed request:  1 (X_CreateWindow)
>  Serial number of failed request:  28
>  Current serial number in output stream:  29
>
> I've checked and as far as I can see all the parameters we're sending to
> XCreateWindow are valid, but I might have missed something:  I don't
> know much about X11 programming.  (The call is
>
>  ::Window xwindow = XCreateWindow(
>    xdisplay, RootWindow(xdisplay, DefaultScreen(xdisplay)),
>    0, 0, 256, 256, 0,
>    xvisualinfo->depth,
>    InputOutput,
>    xvisualinfo->visual,
>    valuemask,
>    &attrib
>  );
>
> but without context that's probably not worth much to others.)
>
>
> Are there any experienced X11 programmers out there who can suggest what
> to do next?
>
> Duncan Murdoch
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595



[Rd] X11 help please
Prof Brian Ripley