NAME

       Font::TTF::Table - Superclass for tables and used for tables we don't have a class for

DESCRIPTION

       Looks after the purely table aspects of a TTF table, such as whether the table has been
       read before, locating the file pointer, etc. Also copies tables from input to output.

INSTANCE VARIABLES

       Instance variables start with a space

       read
           Flag which indicates that the table has already been read from file.

       dat Allows the creation of unspecific tables. Data is simply output to any font file being
           created.

       nocompress
           If set, overrides the font default for WOFF table compression. Is a scalar integer
           specifying a table size threshold below which this table will not be compressed. Set
           to -1 to never compress; 0 to always compress.

       INFILE
           The read file handle

       OFFSET
           Location of the file in the input file

       LENGTH
           Length in the input directory

       ZLENGTH
           Compressed length of the table if a WOFF font. 0 < ZLENGTH < LENGTH implies table is
           compressed.

       CSUM
           Checksum read from the input file's directory

       PARENT
           The Font::TTF::Font that table is part of

METHODS

   Font::TTF::Table->new(%parms)
       Creates a new table or subclass. Table instance variables are passed in at this point as
       an associative array.

   $t->read
       Reads the table from the input file. Acts as a superclass to all true tables.  This method
       marks the table as read and then just sets the input file pointer but does not read any
       data. If the table has already been read, then returns "undef" else returns $self

       For WOFF-compressed tables, the table is first decompressed and a replacement file handle
       is created for reading the decompressed data. In this case ORIGINALOFFSET will preserve
       the original value of OFFSET for applications that care.

   $t->read_dat
       Reads the table into the "dat" instance variable for those tables which don't know any
       better

   $t->out($fh)
       Writes out the table to the font file. If there is anything in the "dat" instance variable
       then this is output, otherwise the data is copied from the input file to the output

   $t->out_xml($context)
       Outputs this table in XML format. The table is first read (if not already read) and then
       if there is no subclass, then the data is dumped as hex data

   $t->XML_element
       Output a particular element based on its contents.

   $t->XML_end($context, $tag, %attrs)
       Handles the default type of <data> for those tables which aren't subclassed

   $t->minsize()
       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.

   $t->dirty($val)
       This sets the dirty flag to the given value or 1 if no given value. It returns the value
       of the flag

   $t->update
       Each table knows how to update itself. This consists of doing whatever work is required to
       ensure that the memory version of the table is consistent and that other parameters in
       other tables have been updated accordingly.  I.e. by the end of sending "update" to all
       the tables, the memory version of the font should be entirely consistent.

       Some tables which do no work indicate to themselves the need to update themselves by
       setting isDirty above 1. This method resets that accordingly.

   $t->empty
       Clears a table of all data to the level of not having been read

   $t->release
       Releases ALL of the memory used by this table, and all of its component/child objects.
       This method is called automatically by 'Font::TTF::Font->release' (so you don't have to
       call it yourself).

       NOTE, that it is important that this method get called at some point prior to the actual
       destruction of the object.  Internally, we track things in a structure that can result in
       circular references, and without calling '"release()"' these will not properly get cleaned
       up by Perl.  Once this method has been called, though, don't expect to be able to do
       anything with the "Font::TTF::Table" object; it'll have no internal state whatsoever.

       Developer note:  As part of the brute-force cleanup done here, this method will throw a
       warning message whenever unexpected key values are found within the "Font::TTF::Table"
       object.  This is done to help ensure that any unexpected and unfreed values are brought to
       your attention so that you can bug us to keep the module updated properly; otherwise the
       potential for memory leaks due to dangling circular references will exist.

BUGS

       No known bugs

AUTHOR

       Martin Hosken <http://scripts.sil.org/FontUtils>.

LICENSING

       Copyright (c) 1998-2016, 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.