View source for Tex sample embedded metapost

=An Example of an Embedded MetaPost Diagram in Plain TeX and AmSTeX=

It is now possible to incorporate MetaPost figures in TeX and AmSTeX documents directly; i.e., without having separate MetaPost input and output files.  Here is a sample file that incorporates such a figure.

 \input luamplib.sty
 
 Meta%
 \mplibcode
 beginfig(1);
     numeric u; u=10pt;
     pickup pencircle scaled .4pt;
     draw fullcircle scaled 1u;
     draw (-.3u,-.1u)..(0,-.3u)..(.3u,-.1u);
     pickup pencircle scaled .8pt;
     draw (0,0);
     draw (-.2u,.2u); draw (.2u,.2u);
 endfig;
 \endmplibcode
 Post!
 
 \bye

If this was stored in a file named '''file.tex''', then one would produce '''file.pdf''' by running the command
 luatex file

This is a very convenient way to include MetaPost figures in TeX and AmSTeX documents.

==Notes==

* This method ''only'' works for producing ''pdf'' files.  It does not work in ''dvi'' mode.
* Note that the command to use is '''luatex'''.  One cannot use '''pdftex''' or '''xetex''', since those engines do not support embedding of MetaPost figures.
* For AmSTeX, add a line '''\input amstex''' ''after'' the initial line '''\input luamplib.sty'''.  It will not work to add this line at the beginning of the file, because AmSTeX handles the "@" character differently.
* The commands '''\mplibcode''' and '''\endmplibcode''' ''must'' occur on lines of their own.  This is because the '''\mplibcode''' macro changes handling of certain characters.
* If you want to have a space before the figure, delete the '''%''' sign just after "Meta".  If you want a space after the figure, add "\ " just before "Post" (''not'' at the end of the previous line—see the note just above this one).

==Do Try This at Home==
If you try this on a machine not on the Math Department network, you will likely find that there is extra space between the characters "Meta" and the figure.  This is because of bugs in the file '''luamplib.sty'''.  The version of this file on the Math department network has been modified to fix this bug.  To fix it for your home machine, copy the file from the math department to your home machine.  On the math department, the file '''luamplib.sty''' is available in one of the following locations (depending on which computer is being used):
 /local/depot/4/texlive-2010/tex/luatex/luamplib/luamplib.sty
 /local/depot/texlive-2010/tex/luatex/luamplib/luamplib.sty
You should copy this file to the corresponding place on your home machine.  This location can be found by running the command
 kpsewhich luamplib.sty