package Font::TTF::OldCmap;
=head1 NAME
Font::TTF::OldCmap - Character map table
This module is deprecated
=head1 DESCRIPTION
Looks after the character map. The primary structure used for handling a cmap
is the L<Font::TTF::Segarr> which handles the segmented arrays of format 4 tables,
and in a simpler form for format 0 tables.
Due to the complexity of working with segmented arrays, most of the handling of
such arrays is via methods rather than via instance variables.
One important feature of a format 4 table is that it always contains a segment
with a final address of 0xFFFF. If you are creating a table from scratch this is
important (although L<Font::TTF::Segarr> can work quite happily without it).
=head1 INSTANCE VARIABLES
The instance variables listed here are not preceeded by a space due to their
emulating structural information in the font.
=over 4
=item Num
Number of subtables in this table
=item Tables
An array of subtables ([0..Num-1])
=back
Each subtables also has its own instance variables which are, again, not
preceeded by a space.
=over 4
=item Platform
The platform number for this subtable
=item Encoding
The encoding number for this subtable
=item Format
Gives the stored format of this subtable
=item Ver
Gives the version (or language) information for this subtable
=item val
This points to a L<Font::TTF::Segarr> which contains the content of the particular
subtable.
=back
=head1 METHODS
=cut
use strict;
use vars qw(@ISA);
require Font::TTF::Table;
require Font::TTF::Segarr;
@ISA = qw(Font::TTF::Table);
=head2 $t->read
Reads the cmap into memory. Format 4 subtables read the whole subtable and
fill in the segmented array accordingly.
Format 2 subtables are not read at all.
=cut
sub read
{
my ($self) = @_;
$self->SUPER::read or return $self;
my ($dat, $i, $j, $k, $id, @ids, $s);
my ($start, $end, $range, $delta, $form, $len, $num, $ver);
my ($fh) = $self->{' INFILE'};
$fh->read($dat, 4);
$self->{'Num'} = unpack("x2n", $dat);
$self->{'Tables'} = [];
for ($i = 0; $i < $self->{'Num'}; $i++)
{
$s = {};
$fh->read($dat, 8);
($s->{'Platform'}, $s->{'Encoding'}, $s->{'LOC'}) = (unpack("nnN", $dat));
$s->{'LOC'} += $self->{' OFFSET'};
push(@{$self->{'Tables'}}, $s);
}
for ($i = 0; $i < $self->{'Num'}; $i++)
{
$s = $self->{'Tables'}[$i];
$fh->seek($s->{'LOC'}, 0);
$fh->read($dat, 6);
($form, $len, $ver) = (unpack("n3", $dat));
$s->{'Format'} = $form;
$s->{'Ver'} = $ver;
if ($form == 0)
{
$s->{'val'} = Font::TTF::Segarr->new;
$fh->read($dat, 256);
$s->{'val'}->fastadd_segment(0, 2, unpack("C*", $dat));
$s->{'Start'} = 0;
$s->{'Num'} = 256;
} elsif ($form == 6)
{
my ($start, $ecount);
$fh->read($dat, 4);
($start, $ecount) = unpack("n2", $dat);
$fh->read($dat, $ecount << 1);
$s->{'val'} = Font::TTF::Segarr->new;
$s->{'val'}->fastadd_segment($start, 2, unpack("n*", $dat));
$s->{'Start'} = $start;
$s->{'Num'} = $ecount;
} elsif ($form == 2)
{
# no idea what to do here yet
} elsif ($form == 4)
{
$fh->read($dat, 8);
$num = unpack("n", $dat);
$num >>= 1;
$fh->read($dat, $len - 14);
$s->{'val'} = Font::TTF::Segarr->new;
for ($j = 0; $j < $num; $j++)
{
$end = unpack("n", substr($dat, $j << 1, 2));
$start = unpack("n", substr($dat, ($j << 1) + ($num << 1) + 2, 2));
$delta = unpack("n", substr($dat, ($j << 1) + ($num << 2) + 2, 2));
$delta -= 65536 if $delta > 32767;
$range = unpack("n", substr($dat, ($j << 1) + $num * 6 + 2, 2));
@ids = ();
for ($k = $start; $k <= $end; $k++)
{
if ($range == 0)
{ $id = $k + $delta; }
else
{ $id = unpack("n", substr($dat, ($j << 1) + $num * 6 +
2 + ($k - $start) * 2 + $range, 2)) + $delta; }
$id -= 65536 if $id > 65536;
push (@ids, $id);
}
$s->{'val'}->fastadd_segment($start, 0, @ids);
}
$s->{'val'}->tidy;
$s->{'Num'} = 0x10000; # always ends here
$s->{'Start'} = $s->{'val'}[0]{'START'};
}
}
$self;
}
=head2 $t->ms_lookup($uni)
Given a Unicode value in the MS table (Platform 3, Encoding 1) locates that
table and looks up the appropriate glyph number from it.
=cut
sub ms_lookup
{
my ($self, $uni) = @_;
$self->find_ms || return undef unless (defined $self->{' mstable'});
return $self->{' mstable'}{'val'}->at($uni);
}
=head2 $t->find_ms
Finds the Microsoft Unicode table and sets the C<mstable> instance variable
to it if found. Returns the table it finds.
=cut
sub find_ms
{
my ($self) = @_;
my ($i, $s, $alt);
return $self->{' mstable'} if defined $self->{' mstable'};
$self->read;
for ($i = 0; $i < $self->{'Num'}; $i++)
{
$s = $self->{'Tables'}[$i];
if ($s->{'Platform'} == 3)
{
$self->{' mstable'} = $s;
last if ($s->{'Encoding'} == 1);
} elsif ($s->{'Platform'} == 0 || ($s->{'Platform'} == 2 && $s->{'Encoding'} == 1))
{ $self->{' mstable'} = $s; }
}
$self->{' mstable'};
}
=head2 $t->out($fh)
Writes out a cmap table to a filehandle. If it has not been read, then
just copies from input file to output
=cut
sub out
{
my ($self, $fh) = @_;
my ($loc, $s, $i, $base_loc, $j);
return $self->SUPER::out($fh) unless $self->{' read'};
$base_loc = $fh->tell();
$fh->print(pack("n2", 0, $self->{'Num'}));
for ($i = 0; $i < $self->{'Num'}; $i++)
{ $fh->print(pack("nnN", $self->{'Tables'}[$i]{'Platform'}, $self->{'Tables'}[$i]{'Encoding'}, 0)); }
for ($i = 0; $i < $self->{'Num'}; $i++)
{
$s = $self->{'Tables'}[$i];
$s->{'val'}->tidy;
$s->{' outloc'} = $fh->tell();
$fh->print(pack("n3", $s->{'Format'}, 0, $s->{'Ver'})); # come back for length
if ($s->{'Format'} == 0)
{
$fh->print(pack("C256", $s->{'val'}->at(0, 256)));
} elsif ($s->{'Format'} == 6)
{
$fh->print(pack("n2", $s->{'Start'}, $s->{'Num'}));
$fh->print(pack("n*", $s->{'val'}->at($s->{'Start'}, $s->{'Num'})));
} elsif ($s->{'Format'} == 2)
{
} elsif ($s->{'Format'} == 4)
{
my ($num, $sRange, $eSel);
my (@deltas, $delta, @range, $flat, $k, $segs, $count);
$num = $#{$s->{'val'}} + 1;
$segs = $s->{'val'};
for ($sRange = 1, $eSel = 0; $sRange <= $num; $eSel++)
{ $sRange <<= 1;}
$eSel--;
$fh->print(pack("n4", $num * 2, $sRange, $eSel, ($num * 2) - $sRange));
$fh->print(pack("n*", map {$_->{'START'} + $_->{'LEN'} - 1} @$segs));
$fh->print(pack("n", 0));
$fh->print(pack("n*", map {$_->{'START'}} @$segs));
for ($j = 0; $j < $num; $j++)
{
$delta = $segs->[$j]{'VAL'}[0]; $flat = 1;
for ($k = $k < $segs->[$j]{'LEN'}; $k++)
{
if ($segs->[$j]{'VAL'}[$k] == 0)
{ $flat = 0; }
if ($delta + $k != $segs->[$j]{'VAL'}[$k])
{
$delta = 0;
last;
}
}
push (@range, $flat);
push (@deltas, ($delta ? $delta - $segs->[$j]{'START'} : 0));
}
$fh->print(pack("n*", @deltas));
$count = 0;
for ($j = 0; $j < $num; $j++)
{
$delta = $deltas[$j];
if ($delta != 0 && $range[$j] == 1)
{ $range[$j] = 0; }
else
{
$range[$j] = ($count + $num - $j) << 1;
$count += $segs->[$j]{'LEN'};
}
}
$fh->print(pack("n*", @range));
for ($j = 0; $j < $num; $j++)
{
next if ($range[$j] == 0);
for ($k = 0; $k < $segs->[$j]{'LEN'}; $k++)
{ $fh->print(pack("n", $segs->[$j]{'VAL'}[$k])); }
}
}
$loc = $fh->tell();
$fh->seek($s->{' outloc'} + 2, 0);
$fh->print(pack("n", $loc - $s->{' outloc'}));
$fh->seek($base_loc + 8 + ($i << 3), 0);
$fh->print(pack("N", $s->{' outloc'} - $base_loc));
$fh->seek($loc, 0);
}
$self;
}
=head2 @map = $t->reverse([$num])
Returns a reverse map of the table of given number or the Microsoft
cmap. I.e. given a glyph gives the Unicode value for it.
=cut
sub reverse
{
my ($self, $tnum) = @_;
my ($table) = defined $tnum ? $self->{'Tables'}[$tnum] : $self->find_ms;
my (@res, $i, $s, $first);
foreach $s (@{$table->{'val'}})
{
$first = $s->{'START'};
map {$res[$_] = $first unless $res[$_]; $first++;} @{$s->{'VAL'}};
}
@res;
}
1;
=head1 BUGS
=over 4
=item *
No support for format 2 tables (MBCS)
=back
=head1 AUTHOR
Martin Hosken L<Martin_Hosken@sil.org>.
=head1 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.
The test suite contains test fonts released under the SIL Open Font License 1.1, see OFL.txt.
=cut