libplot library and applications built on it, such as
plotfont, can use many fonts. These include 22 Hershey vector
fonts, 35 Postscript fonts, 45 PCL 5 fonts, and 18 Hewlett–Packard
vector fonts. We call these 120 supported fonts the `built-in'
fonts. The Hershey fonts are constructed from stroked characters
digitized c. 1967 by Dr. Allen V. Hershey at the U.S. Naval
Surface Weapons Center in Dahlgren, VA. The 35 Postscript fonts
are the outline fonts resident in all modern Postscript printers, and
the 45 PCL 5 fonts are the outline fonts resident in modern
Hewlett–Packard LaserJet printers and plotters. (Of the PCL 5
fonts, the old LaserJet III, which was Hewlett–Packard's first PCL 5 printer, supported only eight: the Univers and CGTimes fonts.) The
18 Hewlett–Packard vector fonts are fonts that are resident in
Hewlett–Packard printers and plotters (mostly the latter).
The Hershey fonts can be used by all types of Plotter supported by
libplot, and the Postscript fonts can be used by X, SVG,
Illustrator, Postscript, and Fig Plotters. So, for example, all
graph can use the Hershey fonts, and
graph -T svg,
graph -T ai,
graph -T ps,
graph -T cgm and
graph -T fig can use the Postscript
fonts. The PCL 5 fonts can be used by by SVG, Illustrator, PCL, and
HP-GL Plotters, and by
graph -T svg,
graph -T ai,
graph -T pcl, and
graph -T hpgl. The Hewlett–Packard
vector fonts can be used by PCL and HP-GL Plotters, and by
-T pcl and
graph -T hpgl. X Plotters and
graph -T X are not restricted to the built-in Hershey and Postscript fonts.
They can use any X Window System font.
plotfont utility, which accepts the ‘-T’ option, will
print a character map of any font that is available in the specified
output format. See plotfont.
For the purpose of plotting text strings (see Text String Format), the 120 built-in fonts are divided into typefaces. As you can see from the following tables, our convention is that in any typeface with more than a single font, font #1 is the normal font, font #2 is italic or oblique, font #3 is bold, and font #4 is bold italic or bold oblique. Additional variants (if any) are numbered #5 and higher.
The 22 Hershey fonts are divided into typefaces as follows.
Nearly all Hershey fonts except the Symbol fonts use the ISO-Latin-1 encoding, which is a superset of ASCII. The Symbol fonts consist of Greek characters and mathematical symbols, and use the symbol font encoding documented in the Postscript Language Reference Manual. By convention, each Hershey typeface contains a symbol font (HersheySerifSymbol or HersheySansSymbol, as appropriate) as font #0.
HersheyCyrillic, HersheyCyrillic-Oblique, and HersheyEUC (which is a Japanese font) are the only non-Symbol Hershey fonts that do not use the ISO-Latin-1 encoding. For their encodings, see Cyrillic and Japanese.
The 35 Postscript fonts are divided into typefaces as follows.
All Postscript fonts except the ZapfDingbats and Symbol fonts use the ISO-Latin-1 encoding. The encodings used by the ZapfDingbats and Symbol fonts are documented in the Postscript Language Reference Manual. By convention, each Postscript typeface contains the Symbol font as font #0.
The 45 PCL 5 fonts are divided into typefaces as follows.
All PCL 5 fonts except the Wingdings and Symbol fonts use the ISO-Latin-1 encoding. The encoding used by the Symbol font is the symbol font encoding documented in the Postscript Language Reference Manual. By convention, each PCL typeface contains the Symbol font as font #0.
The 18 Hewlett–Packard vector fonts are divided into typefaces as follows.
The Hewlett–Packard vector fonts with an asterisk (the ANK and Symbol
fonts) are only available when producing HP-GL/2 graphics, or HP-GL
graphics for the HP7550A graphics plotter and the HP758x, HP7595A and
HP7596A drafting plotters. That is, they are available only if
HPGL_VERSION is "2" (the default) or "1.5". The ANK
fonts are Japanese fonts (see Cyrillic and Japanese), and the Symbol
fonts contain a few miscellaneous mathematical symbols.
All Hewlett–Packard vector fonts except the ANK and Symbol fonts use the ISO-Latin-1 encoding. The Arc fonts are proportional (variable-width) fonts, and the Stick fonts are fixed-width fonts. If HP-GL/2 or HP-GL output is selected, the Arc fonts are assumed to be kerned via device-resident kerning tables. But when producing PCL 5 output, it is assumed that the display device will do no kerning. Apparently Hewlett–Packard dropped support for device-resident kerning tables when emulating HP-GL/2 from within PCL 5. For information about Hewlett–Packard vector fonts and the way in which they are kerned (in HP-GL pen plotters, at least), see the article by L. W. Hennessee et al. in the Nov. 1981 issue of the Hewlett–Packard Journal.
To what extent do the fonts supported by
ligatures? The Postscript fonts, the PCL 5 fonts, and the
Hewlett–Packard vector fonts, at least as implemented in
libplot, do not contain ligatures. However, six of the 22
Hershey fonts contain ligatures. The character combinations "fi", "ff",
"fl", "ffi", and "ffl" are automatically drawn as ligatures in
HersheySerif and HersheySerif-Italic. (Also in the two HersheyCyrillic
fonts and HersheyEUC, since insofar as printable ASCII characters are
concerned, they are identical [or almost identical] to HersheySerif.)
In addition, "tz" and "ch" are ligatures in HersheyGothicGerman.
The German double-s character `ß', which is called an `eszet',
is not treated as a ligature in any font. To obtain an eszet, you
must either request one with the escape sequence "\ss" (see Text String Format), or, if you have an 8-bit keyboard, type an eszet