TITLE

make_volt - Create VOLT code from a TrueType Font

SYNOPSIS

make_volt [-a file] [-l ligtype] [-i file] infile outfile
make_volt -t [-a file] [-l ligtype] [-i file] infile

Creates a copy of the infile font file adding a VOLT table to it.

OPTIONS

-a file       Attachment Point database .xml file
-h            print manpage
-i fontfile   merge VOLT table from this font or text file
-l type       type =
                  first - class name is first code, contents other codes
                  last  - class name is last code, contents other codes
                  firstcomp - treat extensions as part of elements, as first
                  lastcomp - treat extensons as part of elements, as last
-t            output volt code to stdout and don't generate a font file

DESCRIPTION

make_volt aims to make the creation of OpenType fonts much easier. It allows for a font designer to make changes and to feed that changed font forward to merge previously created VOLT code without losing that work. It also creates glyph names, key classes and lookups that can save a lot of work in VOLT.

In addition, make_volt has the capability to merge the volt code it creates with existing volt code either in a font or in a text file.

Glyph naming

Glyphs are named based on the postscript name of the glyph with variants and illegal characters stripped from the name. Name clashes are simply numbered.

Classes

make_volt creates a number of different kind of class. For each attachment point base name (x) a class is created. Class cxDia contains a list of all the glyphs with the attachment point _x. Class cTakesxDia contains all the glyphs with attachment point x. Class cnxDia contains all the glyphs without attachment point _X. And the class cnTakesxDia contains all the glyphs without the x attachment point.

In addition for each glyph name variant (as labelled in a postscript name for a glyh using .var) a class named cvar is created with all the glyphs with that variant in their name. A class named c_novar is also created containing all the corresponding glyphs without the variant, in direct correspondance, so that the non-variant form may be mapped to the variant form using a single rule, for all the glyphs in the class.

Finally a class is created for ligature components. If a glyph is part of a ligature rule it is either the key glyph for the rule or part of the class for the rule. Thus for a rule keyed of a glyph named x there will be two classese: cl_x which is the ligatures involving x and clno_x which contains all the components that correspond to the ligatures found in the other class. This makes a ligature rule a simple 1:1 mapping from clno_x to cl_x.

Ligatures

make_volt has the ability to create ligature mapping lookups. These are controlled by glyph names and follow the approach taken in make_gdl.

SEE ALSO

ttfbuilder, make_gdl