Font::TTF::GDEF - Opentype GDEF table support
The GDEF table contains various global lists of information which are apparantly used in other places in an OpenType renderer. But precisely where is open to speculation...
There are up to 5 tables in the GDEF table, each with their own structure:
This is an Font::TTF::Coverage Class Definition table containing information as to what type each glyph is.
The attach table consists of a coverage table and then attachment points for each glyph in the coverage table:
This is a coverage table
This is an array of point elements. Each element is an array of curve points corresponding to the attachment points on that glyph. The order of the curve points in the array corresponds to the attachment point number specified in the MARKS coverage table (see below).
This contains the ligature caret positioning information for ligature glyphs
A coverage table to say which glyphs are ligatures
An array of elements for each ligature. Each element is an array of information for each caret position in the ligature (there being number of components - 1 of these, generally)
This class definition table defines the classes of mark glyphs that can be selected for processing using the MarkAttachmentType field of lookup FLAG words.
Contains an array of coverage tables indexed by the FILTER value of a lookup.
Reads the table into the data structure
Writes out this table.
Returns the minimum size this table can be. If it is smaller than this, then the table must be bad and should be deleted or whatever.
Sort COVERAGE tables.
Martin Hosken Martin_Hosken@sil.org.
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.
The test suite contains test fonts released under the SIL Open Font License 1.1, see OFL.txt.