Re: make a drawing with Emacs

[Gregory Heytings]

> > I would do that with MetaPost. It allows you to do exactly what you 
> > want: input the data in an Emacs buffer (Emacs has a MetaPost mode), as 
> > a series of geometrical figures and equations, which is compiled into 
> > an image.
>
> Wonderful! Yes, I have `metapost-mode'!
>
> In the repos is texlive-metapost (and -doc)
>
> That's it, I take it?

Yes, that's the (Debian) package, and all you need.

> You have a small example I can compile?

See http://tex.loria.fr/prod-graph/zoonekynd/metapost/metapost.html .

The MetaPost manual is quite readable, and contains many small examples : 
https://www.tug.org/docs/metapost/mpman.pdf .