.TH MPOST 1 "28 April 1995" "Web2C @VERSION@"
.\"=====================================================================
.if n .ds MP MetaPost
.if t .ds MP MetaPost
.if n .ds MF Metafont
.if t .ds MF M\s-2ETAFONT\s0
.if t .ds TX \fRT\\h'-0.1667m'\\v'0.20v'E\\v'-0.20v'\\h'-0.125m'X\fP
.if n .ds TX TeX
.ie t .ds OX \fIT\v'+0.25m'E\v'-0.25m'X\fP\" for troff
.el .ds OX TeX\" for nroff
.\" the same but obliqued
.\" BX definition must follow TX so BX can use TX
.if t .ds BX \fRB\s-2IB\s0\fP\*(TX
.if n .ds BX BibTeX
.\" LX definition must follow TX so LX can use TX
.if t .ds LX \fRL\\h'-0.36m'\\v'-0.15v'\s-2A\s0\\h'-0.15m'\\v'0.15v'\fP\*(TX
.if n .ds LX LaTeX
.if n .ds WB Web
.if t .ds WB W\s-2EB\s0
.\"=====================================================================
.SH NAME
mpost, inimpost, virmpost \- MetaPost, a system for drawing pictures
.SH SYNOPSIS
.B mpost
.RI [ options ]
.RI [ commands ]
.\"=====================================================================
.SH DESCRIPTION
This manual page is not meant to be exhaustive.  The complete
documentation for this version of \*(TX can be found in the info file
or manual
.IR "Web2C: A TeX implementation" .
.PP
\*(MP interprets the \*(MP language and produces PostScript
pictures.  The \*(MP language is similar to Knuth's \*(MF
with additional features for including
.BR tex (1)
or
.BR troff (1)
commands and accessing features of PostScript not found in \*(MF. 
.PP
Like \*(TX and \*(MF, \*(MP is normally used with a large body of
precompiled macros.  This version of \*(MP looks at its command line
to see what name it was called under.  Both
.B inimpost
and
.B virmpost
are symlinks to the
.B mpost
executable.  When called as 
.BR inimpost
(or when the
.B --ini
option is given) it can be used to precompile macros into a
.I .mem
file.  When called as
.B virmpost
it will use the
.I plain
mem.  When called under any other name, \*(MP will use that name as
the name of the mem to use.   For example, when called as
.B mpost
the
.I mpost
mem is used, which is identical to the
.I plain
mem.  Other mems than
.I plain
are rarely used.
.PP
The
.I commands
given on the command line to the \(MP program are passed to it as the
first input line.  (But it is often easier to type extended arguments
as the first input line, since UNIX shells tend to gobble up or
misinterpret \*(MP's favorite symbols, like semicolons, unless you
quote them.)  The first line should begin with a filename, a
.RI \e controlsequence ,
or a
.IR &memname .
.PP
The normal usage is to say
.I mp figs
to process the file
.IR figs.mp .
The basename of
.I figs
becomes the ``jobname'',
and is used in forming output file names.  If no file is named, the
jobname becomes
.IR mpout .
The default extension,
.IR .mp ,
can be overridden by specifying an extension explicitly.
.PP
There is normally one output file for each picture generated,
and the output files are named \fIjobname\fP\fB\^.\^\fP\fInnn\fP,
where \fInnn\fP 
is a number passed to the
.I beginfig
macro.  The output file name
can also be \fIjobname\fP\fB\^.\^\fP\fIps\fP
if this number is negative.
.PP
The output files can be used as figures in a \*(TX document by including
.ce
.BI "\especial{psfile=" jobname.nnn }
in the \*(TX document.  Alternatively, one can
.B \einput epsf.tex
and then use the macro
.ce
.BI "\eepsfbox{" jobname.nnn }
to produce a box of the appropriate size containing the figure.
.TP
.BI btex " TeX commands " etex
This causes
.I mp
to generate a \*(MP picture expression that corresponds to the
\*(TX commands.  If the \*(TX commands generate
more than one line of text, it must be in a
.I \evbox
or a minipage environment.
.TP
.BI verbatimtex " TeX commands " etex
This is ignored by
.I mp
except that the \*(TX commands are passed on to \*(TX.  When using \*(LX
instead of \*(TX the input file must start with a
.I verbatimtex
block that gives the
.I \edocumentstyle
and
.I "\ebegin{document}"
commands.  You can use the `%&' construct in the first verbatimtex
block to ensure that the correct \*(TX format is used to process the
commands.
.PP
Since most \*(TX fonts have to be downloaded as bitmaps, the
.I btex
feature works best when the output of
.I mp
is to be included in a \*(TX document so that
.BR dvips (1)
can download the fonts.  For self-contained PostScript output that can be
used directly or included in a
.I troff
document, start your \*(MP input file with the command
.I "prologues:=1"
and stick to standard PostScript fonts.  \*(TX and \*(MP use the names in the
third column of the file
.IR trfonts.map ,
which can be found in the directories with support files for \*(MP.
.PP
\*(MP output can be included in a
.I troff
document via the
.I "-m pictures"
macro package.  In this case
.I mp
should be invoked with the
.B -T
flag so that the commands between
.I btex
and
.I etex
or between
.I verbatimtex
and
.I etex
are interpreted as
.I troff
instead of \*(TX.  (This automatically sets
.I "prologues:=1"
).
.\"=====================================================================
.SH OPTIONS
This version of \*(MP understands the following command line options.
.TP
.BI --mem \ mem
.rb
Use
.I mem
as the name of the mem to be used, instead of the name by which
\*(MP was called or a
.I %&
line.
.TP
.B --help
.rb
Print help message and exit.
.TP
.B --ini
.rb
Be
.BR inimpost ,
for dumping bases; this is implicitly true if the program is called
as
.BR inimpost .
.TP
.BI --interaction \ mode
.rb
Sets the interaction mode.  The mode can be one of
.IR batchmode ,
.IR nonstopmode ,
.IR scrollmode ,
and
.IR errorstopmode .
The meaning of these modes is the same as that of the corresponding
commands.
.TP
.BI --kpathsea-debug \ bitmask
.rb
Sets path searching debugging flags according to the bitmask.  See the
.I Kpathsea
manual for details.
.TP
.BI --progname \ name
.rb
Pretend to be program
.IR name .
This affects both the format used and the search paths.
.TP
.B -T
.rb
Produce TROFF output.
.TP
.B --troff
.rb
As
.BR -T .
.TP
.B --version
.rb
Print version information and exit.
.\"=====================================================================
.SH ENVIRONMENT
See the Kpathsearch library documentation (the `Path specifications'
node) for the details of how the environment variables are use when
searching.  The
.B kpsewhich
utility can be used to query the values of the variables.
.PP
If the environment variable
TEXMFOUTPUT is set, \*(MP attempts to put its output
files in it, if they cannot be put in the current directory.
.PP
Here is a list of the environment variables affect the behavior of
.IR mp :
.TP
.TP
MPINPUTS
Search path for
.I input
files.
.TP
MFINPUTS
Auxiliary search path for
.I input
files with
.I .mf
extensions.
.TP
MPSUPPORT
Directory for various tables for handling included
.I tex
and
.IR troff .
.TP
MPXCOMMAND
The name of a shell script that converts embedded typesetting commands
to a form that \*(MP understands.  Defaults:
.I makempx
for
.I tex
and
.I troffmpx
for
.IR troff .
.TP
TEX
The version of \*(TX \- or \*(LX \- to use when processing
.I btex
and
.I verbatimtex
commands.  Default
.IR tex .
This version of \*(MP allows you to use a `%&format' line instead.
.TP
TROFF
The
.I troff
pipeline for
.I btex
and
.I verbatimtex
commands.  Default
.I eqn -d\e$\e$ | troff
.TP
MPEDIT
A command template for invoking an editor.
.PP
A
.I .mem
file is a binary file that permits fast loading of macro packages.
.I mpost
reads the default
.I plain.mem
unless another
.I .mem
file is specified at the start of the first line with an
.I &
just before it.  There is also an
.F mfplain.mem
that simulates plain \*(MF so that
.I mpost
can read
.I .mf
fonts.  (Plain \*(MF is described in
.IR "The \*(MF\^book" ).
.PP
Experts can create
.I .mem
files be invoking
.I inimpost
and giving macro definitions followed by a
.I dump
command.
.PP
The \*(MP language is similar to \*(MF, but the manual
.I A User's Manual for \*(MP
assumes no knowledge of \*(MF.  \*(MP does not have bitmap
output commands or \*(MF's online display mechanism.
.\"=====================================================================
.SH FILES
.TP
.I mpost.pool
Encoded text of \*(MP's messages.
.TP
.I *.mem
Predigested \*(MP mem files.
.TP
.I plain.mp
The standard mem file.
.TP
.I mfplain.mp
The \*(MF-compatible mem file.  This is loaded when 
.I virmp
is invoked via a symbolic link as
.IR mfmp .
.TP
.I $TEXMFMAIN/metapost/base/*.mp
The standard \*(MP macros included in the original distribution.
.TP
.I $TEXMFMAIN/metapost/support/*
Various tables for handling included
.I tex
and
.IR troff .
.TP
.I $TEXMFMAIN/metapost/support/trfonts.map
Table of corresponding font names for
.I troff 
and PostScript.
.TP
.I psfonts.map
Table of corresponding font names for
.I tex
and PostScript.
.TP
.I $TEXMFMAIN/doc/metapost/examples.mp
The source file for a few sample figures
that are part of a \*(LX document
.I $TEXMFMAIN/doc/metapost/mpintro.tex 
that describes the \*(MP system 
in a little more detail.
.\"=====================================================================
.SH "SUGGESTED READING"
Donald E. Knuth,
.I "The \*(MF\^book"
(Volume C of
.IR "Computers and Typesetting" ),
Addison-Wesley, 1986, ISBN 0-201-13445-4.
.br
John D. Hobby,
.IR "A User's Manual for \*(MP" ,
CSTR 162, AT&T Bell Labs,
.br
John D. Hobby,
.IR "Drawing Graphs with \*(MP" ,
CSTR 164, AT&T Bell Labs,
.br
.I TUGboat
(the journal of the \*(TX Users Group).
.\"=====================================================================
.SH "SEE ALSO"
.BR tex (1),
.BR mf (1),
.BR dvips (1).
.\"=====================================================================
.SH AUTHORS
\*(MP was designed by John D. Hobby, incorporating algorithms from 
\*(MF by Donald E. Knuth.  It was originally implemented on Unix,
incorporating system-dependent routines from
.BR web2c ,
while not relying on it exccept for the actual \*(WB-to-C translator.
.PP
Ulrik Vieth adapted \*(MP to take advantage of the advanced path 
searching features in more recent versions of
.B web2c
and worked towards fully integrating \*(MP into the canonical Unix 
\*(TX distribution.  He also updated and extended this manual page.
.\"=====================================================================
.SH TRIVIA
Unlike \*(TX and \*(MF, \*(MP originally didn't use any fancy logo.
John Hobby says he prefers the spelling ``MetaPost'', yet Don Knuth 
has updated the \*(MF 
.I logo.mf
font to be able to typeset a proper \*(MP logo similar to the \*(MF 
logo.  Feel free to use whatever you think is more approporiate!