NAME¶
Font::TTF::Coverage - Opentype coverage and class definition objects
DESCRIPTION¶
Coverage tables and class definition objects are virtually identical concepts in
OpenType. Their difference comes purely in their storage. Therefore we can say
that a coverage table is a class definition in which the class definition for
each glyph is the corresponding index in the coverage table. The resulting
data structure is that a Coverage table has the following fields:
- cover
- A boolean to indicate whether this table is a coverage table (TRUE) or a
class definition (FALSE)
- val
- A hash of glyph ids against values (either coverage index or class
value)
- fmt
- The storage format used is given here, but is recalculated when the table
is written out.
- count
- A count of the elements in a coverage table for use with add. Each
subsequent addition is added with the current count and increments the
count.
- max
- Maximum class value in a class table.
METHODS¶
new($isCover [, vals])¶
Creates a new coverage table or class definition table, depending upon the value
of $isCover. if $isCover then vals may be a list of glyphs to include in
order. If no $isCover, then vals is a hash of glyphs against class values.
read($fh)¶
Reads the coverage/class table from the given file handle
out($fh, $state)¶
Writes the coverage/class table to the given file handle. If $state is 1 then
the output string is returned rather than being output to a filehandle.
$c->add($glyphid[, $class])¶
Adds a glyph id to the coverage or class table. Returns the index or class
number of the glyphid added.
$c->signature¶
Returns a vector of all the glyph ids covered by this coverage table or class
@map=$c->sort¶
Sorts the coverage table so that indexes are in ascending order of glyphid.
Returns a map such that $map[$new_index]=$old_index.
$c->out_xml($context)¶
Outputs this coverage/class in XML
AUTHOR¶
Martin Hosken Martin_Hosken@sil.org.
LICENSING¶
Copyright (c) 1998-2013, SIL International (
http://www.sil.org)
This module is released under the terms of the Artistic License 2.0. For
details, see the full text of the license in the file LICENSE.