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 subtables 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
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 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.
