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load fonts fonts.
For details on SM's implementation of TeX and the `traditional' style see the section in the main body of this manual (see section Drawing Labels and SM's TeX Emulation).
The characters in a font are specified using a programme read_fonts
which you can use to make binary font files from the list of
Hershey characters, using an index file to specify what character
should go where. The binary fonts file also specifies which TeX
`definitions' are available (e.g. \alpha). The first 4 bytes
of the file are an integer (in binary) that specifies the format of
the file; when the format is changed in an incompatible way this number
if changed and you will have to rebuild your font files (`make fonts')/
The default font table is
illustrated at the end of this appendix. Which font file you want to
use is specified as the fonts entry in your `.sm' file.
@footnote ${It's possible to resurrect the font table used by
pre-2.0 versions of SM, using the index file
`old_font_index'}.
The fonts.bin fonts have been cleaned up a bit for version 2.0
of SM, although the
order of characters in the greek and roman fonts is unchanged. There
is a new font, `Old English' or \o or \oe, and a good number of new
characters are provided. Neither of these fonts supports the `private'
font, that is there in case users desperately need something,
when they can make their own binary font file. For example, there is a
set of Hershey oriental fonts that could be used (we have it somewhere).
The complete list of (occidental) Hershey
characters is given in a file called hershey_oc.dat, and is in
the public domain. Each character is specified by a number in the
first 5 columns, then a number of strokes in the next 3, then pairs of
letters in the remaining columns up to 72, and in as many 72 character
lines as are needed. (Annoyingly, if a line consists of exactly 72
characters, the next must be left blank).
Each pair of characters consists of a coordinate,
with the origin at (R,R), and the y axis pointing down.
A ` ' indicates that the next point is a move, otherwise just
connect the dots. The very first pair is different, as it specifies
the left and right spacing for the character. If this isn't clear, try
drawing a few characters on graph paper, character 2001 (roman A) for example.
There are a few characters that have
traditionally been available in Mongo that are not in the Hershey set,
these have been added to the end of the `hershey_oc.dat' file, plus a
few that we thought deserved adding.
If you want to create your own characters, the macro make_char in
`fonts' (i.e. load fonts make_char) might help. It uses the
cursor to make a string that is (nearly) in the correct form for
inclusion in `hershey_oc.dat'
The programme read_fonts reads this file,
an `index' file that specifies the characters to be put into the
fonts, and a list of TeX definitions. The index file consists of
character numbers, or ranges
consisting of two numbers separated by a minus sign. Comments go from
the character # to end of line. Each font consists of 96 characters
in ascii order, and fonts appear in the index in the order
rm, gr, sc, ti, oe, and pr.
The format of the TeX definition file
is that each definition has a line to itself, lines starting with a
# are comments. A line consists of a name, some whitespace, the number
of arguments (optional, defaults to zero), the name
of the font to use, a single white-space character, and the value of
the definition to the end of the line; you can continue onto another line
by putting a \ at the end of the line. You can use any of the normal
font specifications, or cu which means use the current font.
For example
alpha gr a alsoalpha 0 cu \gr a alphatoo 1 gr \#1adefines
\alpha the conventional way as the character a
in the greek font, then defines alsoalpha in a less efficient
way (by specifying the current font, then explicitly switching to
greek), then defines alphatoo as a large
, used as \alphatoo5. There's no reason
why your definitions can't be reasonably complicated, see for example
the definition of \TeX.
The main Makefile prepares your binary font file for you.
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