#======================================================================= # ____ ____ _____ _ ____ ___ ____ # | _ \| _ \| ___| _ _ / \ | _ \_ _| |___ \ # | |_) | | | | |_ (_) (_) / _ \ | |_) | | __) | # | __/| |_| | _| _ _ / ___ \| __/| | / __/ # |_| |____/|_| (_) (_) /_/ \_\_| |___| |_____| # # 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: Head.pm,v 2.0 2005/11/16 02:16:00 areibens Exp $ # #======================================================================= package PDF::API2::Basic::TTF::Head; =head1 NAME PDF::API2::Basic::TTF::Head - The head table for a TTF Font =head1 DESCRIPTION This is a very basic table with just instance variables as described in the TTF documentation, using the same names. One of the most commonly used is C<unitsPerEm>. =head1 INSTANCE VARIABLES The C<head> table has no internal instance variables beyond those common to all tables and those specified in the standard: version fontRevision checkSumAdjustment magicNumber flags unitsPerEm created modified xMin yMin xMax yMax macStyle lowestRecPPEM fontDirectionHint indexToLocFormat glyphDataFormat The two dates are held as an array of two unsigned longs (32-bits) =head1 METHODS =cut use strict; use vars qw(@ISA %fields @field_info); require PDF::API2::Basic::TTF::Table; use PDF::API2::Basic::TTF::Utils; @ISA = qw(PDF::API2::Basic::TTF::Table); @field_info = ( 'version' => 'f', 'fontRevision' => 'f', 'checkSumAdjustment' => 'L', 'magicNumber' => 'L', 'flags' => 'S', 'unitsPerEm' => 'S', 'created' => 'L2', 'modified' => 'L2', 'xMin' => 's', 'yMin' => 's', 'xMax' => 's', 'yMax' => 's', 'macStyle' => 'S', 'lowestRecPPEM' => 'S', 'fontDirectionHint' => 's', 'indexToLocFormat' => 's', 'glyphDataFormat' => '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 $t->read Reads the table into memory thanks to some utility functions =cut sub read { my ($self) = @_; my ($dat); $self->SUPER::read || return $self; init unless defined $fields{'Ascender'}; $self->{' INFILE'}->read($dat, 54); TTF_Read_Fields($self, $dat, \%fields); $self; } =head2 $t->out($fh) Writes the table to a file either from memory or by copying. If in memory (which is usually) the checkSumAdjustment field is set to 0 as per the default if the file checksum is not to be considered. =cut sub out { my ($self, $fh) = @_; return $self->SUPER::out($fh) unless $self->{' read'}; # this is never true # $self->{'checkSumAdjustment'} = 0 unless $self->{' PARENT'}{' wantsig'}; $fh->print(TTF_Out_Fields($self, \%fields, 54)); $self; } =head2 $t->XML_element($context, $depth, $key, $value) Handles date process for the XML exporter =cut sub XML_element { my ($self) = shift; my ($context, $depth, $key, $value) = @_; my ($fh) = $context->{'fh'}; my ($output, @time); my (@month) = qw(JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC); return $self->SUPER::XML_element(@_) unless ($key eq 'created' || $key eq 'modified'); @time = gmtime($self->getdate($key eq 'created')); $output = sprintf("%d/%s/%d %d:%d:%d", $time[3], $month[$time[4]], $time[5] + 1900, $time[2], $time[1], $time[0]); $fh->print("$depth<$key>$output</$key>\n"); $self; } =head2 $t->update Updates the head table based on the glyph data and the hmtx table =cut sub update { my ($self) = @_; my ($num, $i, $loc, $hmtx); my ($xMin, $yMin, $xMax, $yMax, $lsbx); return undef unless ($self->SUPER::update); $num = $self->{' PARENT'}{'maxp'}{'numGlyphs'}; return undef unless (defined $self->{' PARENT'}{'hmtx'} && defined $self->{' PARENT'}{'loca'}); $hmtx = $self->{' PARENT'}{'hmtx'}->read; $self->{' PARENT'}{'loca'}->update; $hmtx->update; # if we updated, then the flags will be set anyway. $lsbx = 1; for ($i = 0; $i < $num; $i++) { $loc = $self->{' PARENT'}{'loca'}{'glyphs'}[$i]; next unless defined $loc; $loc->read->update_bbox; $xMin = $loc->{'xMin'} if ($loc->{'xMin'} < $xMin || $i == 0); $yMin = $loc->{'yMin'} if ($loc->{'yMin'} < $yMin || $i == 0); $xMax = $loc->{'xMax'} if ($loc->{'xMax'} > $xMax); $yMax = $loc->{'yMax'} if ($loc->{'yMax'} > $yMax); $lsbx &= ($loc->{'xMin'} == $hmtx->{'lsb'}[$i]); } $self->{'xMin'} = $xMin; $self->{'yMin'} = $yMin; $self->{'xMax'} = $xMax; $self->{'yMax'} = $yMax; if ($lsbx) { $self->{'flags'} |= 2; } else { $self->{'flags'} &= ~2; } $self; } =head2 $t->getdate($is_create) Converts font modification time (or creation time if $is_create is set) to a 32-bit integer as returned from time(). Returns undef if the value is out of range, either before the epoch or after the maximum storable time. =cut sub getdate { my ($self, $is_create) = @_; my ($arr) = $self->{$is_create ? 'created' : 'modified'}; $arr->[1] -= 2082844800; # seconds between 1/Jan/1904 and 1/Jan/1970 (midnight) if ($arr->[1] < 0) { $arr->[1] += 0xFFFFFFF; $arr->[1]++; $arr->[0]--; } return undef if $arr->[0] != 0; return $arr->[1]; } =head2 $t->setdate($time, $is_create) Sets the time information for modification (or creation time if $is_create is set) according to the 32-bit time information. =cut sub setdate { my ($self, $time, $is_create) = @_; my (@arr); $arr[1] = $time; if ($arr[1] >= 0x83DA4F80) { $arr[1] -= 0xFFFFFFFF; $arr[1]--; $arr[0]++; } $arr[1] += 2082844800; $self->{$is_create ? 'created' : 'modified'} = \@arr; $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