[metapost] MetaPost and LuaTeX

[Dirk Laurie]

I have the following perceptions:

1. LuaTeX is in stable release 0.60 but the developers don't really want
   the public to write anything in it yet since a lot may change.
2. They therefore have on purpose not written any primer or anything
   else that will make it attractive to non-geeks.  
3. The MetaPost capability of lualatex sits entirely inside the Lua part.  
4. You can get MetaPost capability inside LaTeX with \usepackage{luamplib}, 
   which however is documented for other developers, not for users.
5. luamplib.sty is fairly short and you can easily see the handful of
   commands available.  Use at your own risk though.

I will like nothing more than to be told that these perceptions
are out of date.

My own level of MetaPost expertise in LuaTeX has progressed to the
point where I can insert the following code copied from 
    http://www.luatex.org/talks/print-plain-tug-2009.pdf,
and am just clever enough to change the first and last lines
to LaTeX usage:

\begin{mplibcode}
beginfig(1);
draw fullcircle
scaled 10cm
withcolor red
withpen pencircle xscaled 4mm yscaled 2mm rotated 30 ;
endfig;
\end{mplibcode}

I then admire the nice big red circle which appears at just that point 
in the document.  

But I am not expert enough to figure out why the circle is not drawn 
with that pen, but with an ordinary pen of constant thickness.

I am in the process of improving my expertise through the tried and
trusted scientific method of experimentation.  But a little advice
(it does not need to be friendly advice) may come in handy.

Dirk