[help-texinfo] Embed pstricks, metapost or asymptote markup in texinfo ?

[B Thomas]

Hi,

Is it possible to embed pstricks, metapost or asymptote markup
in texinfo source? For instance to put a pspicture environment
between @tex and @end tex. Also is it possible to change the
latex preamble for the generated document? For instance to
include "\usepackage{pst-plot}". Alternatively can postscript
code be embeded directly in the info source ?

sincerely
b thomas