#=======================================================================
# ____ ____ _____ _ ____ ___ ____
# | _ \| _ \| ___| _ _ / \ | _ \_ _| |___ \
# | |_) | | | | |_ (_) (_) / _ \ | |_) | | __) |
# | __/| |_| | _| _ _ / ___ \| __/| | / __/
# |_| |____/|_| (_) (_) /_/ \_\_| |___| |_____|
#
# A Perl Module Chain to faciliate the Creation and Modification
# of High-Quality "Portable Document Format (PDF)" Files.
#
#=======================================================================
#
# THIS IS A REUSED PERL MODULE, FOR PROPER LICENCING TERMS SEE BELOW:
#
#
# Copyright Martin Hosken <Martin_Hosken@sil.org>
#
# No warranty or expression of effectiveness, least of all regarding
# anyone's safety, is implied in this software or documentation.
#
# This specific module is licensed under the Perl Artistic License.
#
#
# $Id: Hhea.pm,v 2.0 2005/11/16 02:16:00 areibens Exp $
#
#=======================================================================
=head1 NAME
PDF::API2::Basic::TTF::Hhea - Horizontal Header table
=head1 DESCRIPTION
This is a simplte table with just standards specified instance variables
=head1 INSTANCE VARIABLES
version
Ascender
Descender
LineGap
advanceWidthMax
minLeftSideBearing
minRightSideBearing
xMaxExtent
caretSlopeRise
caretSlopeRun
metricDataFormat
numberOfHMetrics
=head1 METHODS
=cut
use strict;
use vars qw(@ISA %fields @field_info);
@ISA = qw(PDF::API2::Basic::TTF::Table);
@field_info = (
'version' => 'f',
'Ascender' => 's',
'Descender' => 's',
'LineGap' => 's',
'advanceWidthMax' => 'S',
'minLeftSideBearing' => 's',
'minRightSideBearing' => 's',
'xMaxExtent' => 's',
'caretSlopeRise' => 's',
'caretSlopeRun' => 's',
'metricDataFormat' => '+10s',
'numberOfHMetrics' => 'S');
sub init
{
my ($k, $v, $c, $i);
for ($i = 0; $i < $#field_info; $i += 2)
{
($k, $v, $c) = TTF_Init_Fields($field_info[$i], $c, $field_info[$i + 1]);
next unless defined $k && $k ne "";
$fields{$k} = $v;
}
}
=head2 $t->read
Reads the table into memory as instance variables
=cut
sub read
{
my ($self) = @_;
my ($dat);
$self->SUPER::read or return $self;
init unless defined $fields{'Ascender'};
$self->{' INFILE'}->read($dat, 36);
TTF_Read_Fields($self, $dat, \%fields);
$self;
}
=head2 $t->out($fh)
Writes the table to a file either from memory or by copying.
=cut
sub out
{
my ($self, $fh) = @_;
return $self->SUPER::out($fh) unless $self->{' read'};
$self->{'numberOfHMetrics'} = $self->{' PARENT'}{'hmtx'}->numMetrics || $self->{'numberOfHMetrics'};
$fh->print(TTF_Out_Fields($self, \%fields, 36));
$self;
}
=head2 $t->update
Updates various parameters in the hhea table from the hmtx table, assuming
the C<hmtx> table is dirty.
=cut
sub update
{
my ($self) = @_;
my ($hmtx) = $self->{' PARENT'}{'hmtx'};
my ($glyphs);
my ($num);
my ($i, $maw, $mlsb, $mrsb, $mext, $aw, $lsb, $ext);
return undef unless ($self->SUPER::update);
return undef unless (defined $hmtx && defined $self->{' PARENT'}{'loca'});
$hmtx->read->update;
$self->{' PARENT'}{'loca'}->read->update;
$glyphs = $self->{' PARENT'}{'loca'}{'glyphs'};
$num = $self->{' PARENT'}{'maxp'}{'numGlyphs'};
return undef unless ($hmtx->{' isDirty'} || $self->{' PARENT'}{'loca'}{' isDirty'});
for ($i = 0; $i < $num; $i++)
{
$aw = $hmtx->{'advance'}[$i];
$lsb = $hmtx->{'lsb'}[$i];
if (defined $glyphs->[$i])
{ $ext = $lsb + $glyphs->[$i]->read->{'xMax'} - $glyphs->[$i]{'xMin'}; }
else
{ $ext = $aw; }
$maw = $aw if ($aw > $maw);
$mlsb = $lsb if ($lsb < $mlsb or $i == 0);
$mrsb = $aw - $ext if ($aw - $ext < $mrsb or $i == 0);
$mext = $ext if ($ext > $mext);
}
$self->{'advanceWidthMax'} = $maw;
$self->{'minLeftSideBearing'} = $mlsb;
$self->{'minRightSideBearing'} = $mrsb;
$self->{'xMaxExtent'} = $mext;
$self->{'numberOfHMetrics'} = $hmtx->numMetrics;
$self;
}
1;
=head1 BUGS
None known
=head1 AUTHOR
Martin Hosken Martin_Hosken@sil.org. See L<PDF::API2::Basic::TTF::Font> for copyright and
licensing.
=cut