NAME
Font::TTF::Cmap - Character map table
DESCRIPTION
Looks after the character map. For ease of use, the actual cmap is held in a hash against codepoint. Thus for a given table:
$gid = $font->{'cmap'}{'Tables'}[0]{'val'}{$code};Note that $code should be a true value (0x1234) rather than a string representation.
INSTANCE VARIABLES
The instance variables listed here are not preceded by a space due to their emulating structural information in the font.
- Num
-
Number of subtables in this table
- Tables
-
An array of subtables ([0..Num-1])
Each subtable also has its own instance variables which are, again, not preceded by a space.
- Platform
-
The platform number for this subtable
- Encoding
-
The encoding number for this subtable
- Format
-
Gives the stored format of this subtable
- Ver
-
Gives the version (or language) information for this subtable
- val
-
A hash keyed by the codepoint value (not a string) storing the glyph id
The following cmap options are controlled by instance variables that start with a space:
- allowholes
-
By default, when generating format 4 cmap subtables character codes that point to glyph zero (normally called .notdef) are not included in the subtable. In some cases including some of these character codes can result in a smaller format 4 subtable. To enable this behavior, set allowholes to non-zero.
METHODS
$t->read
Reads the cmap into memory. Format 4 subtables read the whole subtable and fill in the segmented array accordingly.
$t->ms_lookup($uni)
Finds a Unicode table, giving preference to the MS one, and looks up the given Unicode codepoint in it to find the glyph id.
$t->find_ms
Finds the a Unicode table, giving preference to the Microsoft one, and sets the mstable instance variable to it if found. Returns the table it finds.
$t->ms_enc
Returns the encoding of the microsoft table (0 => symbol, etc.). Returns undef if there is no Microsoft cmap.
$t->out($fh)
Writes out a cmap table to a filehandle. If it has not been read, then just copies from input file to output
$t->XML_element($context, $depth, $name, $val)
Outputs the elements of the cmap in XML. We only need to process val here
$t->minsize()
Returns the minimum size this table can be in bytes. If it is smaller than this, then the table must be bad and should be deleted or whatever.
$t->update
Tidies the cmap table.
Removes MS Fmt12 cmap if it is no longer needed.
Removes from all cmaps any codepoint that map to GID=0. Note that such entries will be re-introduced as necessary depending on the cmap format.
@map = $t->reverse(%opt)
Returns a reverse map of the Unicode cmap. I.e. given a glyph gives the Unicode value for it. Options are:
- tnum
-
Table number to use rather than the default Unicode table
- array
-
Returns each element of reverse as an array since a glyph may be mapped by more than one Unicode value. The arrays are unsorted. Otherwise store any one unicode value for a glyph.
is_unicode($index)
Returns whether the table of a given index is known to be a unicode table (as specified in the specifications)
BUGS
Format 14 (Unicode Variation Sequences) cmaps are not supported.
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.