automatic or scripted export of graphics from gnumeric

[John Denker <jsd av8n com>]

Hi Folks --

By way of background and by way of analogy:  I have a great many .svg files.
I have scripts and makefiles that automagically convert them to .pdf and .png
format if/whenever needed.  This relies on the script-friendly export features
of the inkscape command-line interface.  This is an important part of the project
workflow.

I also have a great many .gnumeric files containing graphs.

Desired behavior:  It would be reeeeally nice to export those graphs in .pdf
or .png or whatever format, in a way that could be *automated* as part of the
project workflow.

Observed behavior:  Right now, to export the graphics, I have to open each
.gnumeric file and do a bunch of work by hand.  In particular, I cannot
simply do
     git pull ; make
and expect the graphs images to be up-to-date.

Question:  Is there a way to automate this?  I'm pretty sure ssconvert doesn't
know how to do it.  Is there some other tool?

If not, how hard would it be to implement this, as part of ssconvert or otherwise?

I can think of several reasons why it wouldn't be easy, but it doesn't sound
impossible, and it would be reeeeeally nice.