In this section, we shall learn how we can reconfigure fontinst to obtain fonts customized for our typographic needs: with accented letters, slanted letters, colored letters, special ligatures, letterspacing, special behavior, etc. First, however, we must study the mechanism by which fontinst describes a virtual font and then apply it to a number of interesting examples.
Here is the philosophy of fontinst:
To produce a virtual font, we need a font encoding and a set of glyphs. The encoding is describen in an ETX file (extension .etx); the glyphs are described in a set of MTX files (extension .mtx).
Each \setslot entry in an encoding file is associated with a number (the position of the glyph in the encoding) and contains a glyph's name. In an entry in an encoding file, we can also provide other information:
Any ligatures (\ligature) whose sequences begin with the glyph in question
The fact that the glyph is part of a sequence of substitutions, as in mathematical fonts, or a set of large mathematical delimiters (see Appendix B.1.4, where we describe these gadgets)
A glyph must be defined by a \setglyph instruction. It may later be redefined (\resetglyph).
The behavior of a glyph with respect to kerning may be similar to that of another glyph; for instance, 'é' kerns in the same way as 'e'. This fact is established through the instructions \setleftrightkerning, \setleftkerning, and \setrightkerning ...