[NTG-context] Rendering Standalone MetaPost Graphics with ConTeXt

[Vincent Hennebert]

I’d like to use MetaPost to generate all sorts of standalone graphics
(ultimately converted to SVG). For various reasons (among others,
MetaFun and advanced text processing) I want to use MetaPost as
embedded in ConTeXt rather than a standalone installation.

---- metapost.mp ----
fill fullcircle scaled 10cm;
----

Whether I run
  context metapost.mp
or
  mtxrun --script metapost metapost.mp
I get a PDF document that contains no page.

The mtxrun version generates the following temp file:
---- mptopdf-temp.tex ----
\starttext
\startMPinclusions
fill fullcircle scaled 10cm;
\stopMPinclusions
\stoptext
----

Looking at the wiki, it seems that \startMPinclusions is not meant to
actually render any content, just to include MetaPost code like
function definitions. I guess I would have expected \startMPpage
instead.

Am I doing something wrong, or is that an error in ConTeXt?

Thanks,
Vincent