MF

Section: User Commands (1)
Updated: 23 January 1994
Index Return to Main Contents

NAME

mf, inimf, virmf - Metafont, a language for font and logo design

SYNOPSIS

mf [ first line ]

inimf [ first line ]

virmf [ first line ]

DESCRIPTION

Metafont reads the program in the specified files and outputs font rasters (in gf format) and font metrics (in tfm format). The Metafont language is described in The Metafontbook.

Like TeX, Metafont is normally used with a large body of precompiled macros, and font generation in particular requires the support of several macro files. The basic program as compiled is called inimf; it can be used to precompile macros into a .base file. The virmf variant is used to reload the .base files quickly. Typically, virmf has links to it by the names of the various base files. For example, if you link virmf to foo and then execute the program foo, you get the base file foo.base. You can load a different base by saying, e.g., virmf \\&mybase.

As described in The Metafontbook, the command line (or first input line) should otherwise begin with a file name or a \controlsequence. The normal usage is to say

: mf '\mode=<printengine>; [mag=magstep(n);]' input font

to start processing font.mf. The single quotes are the best way of keeping the Unix shell from misinterpreting the semicolons and from removing the \ character, which is needed here to keep Metafont from thinking that you want to produce a font called mode. (Or you can just say mf and give the other stuff on the next line, without quotes.) Other control sequences, such as batchmode (for silent operation) can also appear. The name font will be the ``jobname'', and is used in forming output file names. If Metafont doesn't get a file name in the first line, the jobname is mfput. The default extension, .mf, can be overridden by specifying an extension explicitly.

A log of error messages goes into the file jobname.log. The output files are jobname.tfm and jobname.<number>gf, where <number> depends on the resolution and magnification of the font. The mode in this example is shown generically as <printengine>, a symbolic term for which the name of an actual device or, most commonly, the name localfont (see below) must be substituted. If the mode is not specified or is not valid for your site, Metafont will default to proof mode which produces large character images for use in font design and refinement. Proof mode can be recognized by the suffix .2602gf after the jobname. Examples of proof mode output can be found in Computer Modern Typefaces (Volume E of Computers and Typesetting). The system of magsteps is identical to the system used by TeX, with values generally in the range 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0. A listing of gf numbers for 118-dpi, 240-dpi and 300-dpi fonts is shown below.

MAGSTEP118 dpi240 dpi300 dpi

mag=magstep(0)118240300

mag=magstep(0.5)129263329

mag=magstep(1)142288360

mag=magstep(2)170346432

mag=magstep(3)204415518

mag=magstep(4)245498622

mag=magstep(5)294597746



Magnification can also be specified not as a magstep but as an
arbitrary value, such as 1.315, to create special character sizes.

Before font production can begin, it is necessary to set up the
appropriate base files.  The minimum set of components for font
production for a given print-engine is the
plain.mf
macro file
and the local
mode_def
file.  The macros in
plain.mf
can be
studied in an appendix to the
Metafontbook;
they were developed by Donald E. Knuth, and this file should never be
altered except when it is officially upgraded.
Each
mode_def
specification helps adapt fonts to a particular print-engine.
There is a regular discussion of
mode_defs
in
TUGboat,
the journal of the
TeX
Users Group.
The local ones in use on this computer should be in
/ade/lib/texmf/mf/modes.mf.
With only
plain.mf
and the
modes
file loaded it is possible to
create fonts of simple characters, such as those used for the
Metafont
logo, and those used for the LaTeX line and circle fonts,
but the production of Computer Modern fonts would be speeded by
making a
cmmf.base
file (which includes the macros in
cmbase.mf
as
well as those in
plain.mf).

Several environment variables can be used to set up directory
paths to search when Metafont opens a file for input.
For example, the
csh
command
setenv MFINPUTS .:~me/mylib:/ade/lib/texmf/mf

or the
sh
command sequence
MFINPUTS=.:~me/mylib:/ade/lib/texmf/mf
export MFINPUTS

would cause all invocations of Metafont and its derivatives to look for \input files first in the current directory, then in a hypothetical user's mylib, and finally in the system library. Normally, the user will place the command sequence which sets up the MFINPUTS environment variable in his or her .login or .profile file.

The e response to Metafont's error-recovery mode invokes the system default editor at the erroneous line of the source file. There is an environment variable, MFEDIT, that overrides the default editor. It should contain a string with "%s" indicating where the filename goes and "%d" indicating where the decimal linenumber (if any) goes. For example, an MFEDIT string for the vi editor can be set with the csh command

: setenv MFEDIT "/usr/ucb/vi +%d %s"

The ENVIRONMENT section below lists the relevant environment variables, and their defaults.

A convenient file in the library is null.mf, containing nothing. When mf can't find the file it thinks you want to input, it keeps asking you for another file name; responding `null' gets you out of the loop if you don't want to input anything.

ONLINE GRAPHICS OUTPUT

Metafont can use most modern displays, so you can see its output without printing. Chapter 23 of The Metafontbook describes what you can do. This implementation of Metafont uses environment variables to determine which display device you want to use. First it looks for a variable MFTERM, and then for TERM. If it can't find either, you get no online output. Otherwise, the value of the variable determines the device to use: hp2627, sun (for SunView), tek, uniterm (for an Atari ST Tek 4014 emulator), xterm (for either X10 or X11). Some of these devices may not be supported in all Metafont executables; the choice is made at compilation time.

ENVIRONMENT

The default values for all environment variables are set at the time of compilation in the file kpathsea/paths.h. See the Kpathsearch library documentation (the `Path specifications' node) for the details of the searching.

If the environment variable TEXMFOUTPUT is set, Metafont attempts to put its output files in it, if they cannot be put in the current directory. Again, see tex(1).

MFINPUTS: Search path for input and openin files. Default:
@DEFAULT_MF_PATH@
MFBASES: Search path for base files. Default: @DEFAULT_BASE_PATH@
MFPOOL: Search path for Metafont internal strings. (Used by inimf only.) Default: @DEFAULT_MFPOOL_PATH@
MFEDIT: Command template for switching to editor. Default: vi +%d %s
MFTERM: Determines the online graphics display. If MFTERM is not set, and DISPLAY is set, the Metafont window support for X is used. (DISPLAY must be set to a valid X server specification, as usual.) If neither MFTERM nor DISPLAY is set, TERM is used to guess the window support to use.
MAKETEXMF: Analogous to TeX's MAKETEXTEX, q.v.
USE_MAKETEXMF: Analogous.

FONT UTILITIES

A number of utility programs are available. The following is a partial list of available utilities and their purpose. Consult your local Metafont guru for details.

gftopk: Takes a gf file and produces a more tightly packed pk font file.
gftodvi: Produces proof sheets for fonts.
gftype: Displays the contents of a gf file in mnemonics and/or images.
pktype: Mnemonically displays the contents of a pk file.
mft: Formats a source file as shown in Computer Modern Typefaces.

FILES

/ade/lib/texmf/ini/mf.pool: Encoded text of Metafont's messages.
/ade/lib/texmf/ini/*.base: Predigested Metafont base files.
/ade/lib/texmf/mf//plain.mf: The standard base.
/ade/lib/texmf/mf//modes.mf: The file of mode_defs for your site's various printers

COMMENTS

Warning: ``Type design can be hazardous to your other interests. Once you get hooked, you will develop intense feelings about letterforms; the medium will intrude on the messages that you read. And you will perpetually be thinking of improvements to the fonts that you see everywhere, especially those of your own design.''

BUGS

On January 4, 1986 the ``final'' bug in Metafont was discovered and removed. If an error still lurks in the code, Donald E. Knuth promises to pay a finder's fee which doubles every year to the first person who finds it. Happy hunting.

AUTHORS

Metafont was designed by Donald E. Knuth, who implemented it using his Web system for Pascal programs. It was originally ported to Unix by Paul Richards at the University of Illinois at Urbana-Champaign. This page was mostly written by Pierre MacKay.

This document was created by man2html, using the manual pages.
Time: 15:35:49 GMT, January 15, 2023

MF