#!/usr/bin/perl
#
# bdftruncate.pl -- Markus Kuhn
#
# This Perl script allows you to generate from an ISO10646-1 encoded
# BDF font other ISO10646-1 BDF fonts in which all characters above
# a threshold code value are stored unencoded.
#
# $ucs-fonts: bdftruncate.pl,v 1.7 2004-11-28 18:41:13+00 mgk25 Rel $
# Subroutine to identify whether the ISO 10646/Unicode character code
# ucs belongs into the East Asian Wide (W) or East Asian FullWidth
# (F) category as defined in Unicode Technical Report #11.
sub iswide ($) {
my $ucs = shift(@_);
return ($ucs >= 0x1100 &&
($ucs <= 0x115f || # Hangul Jamo
($ucs >= 0x2e80 && $ucs <= 0xa4cf &&
($ucs & ~0x0011) != 0x300a && $ucs != 0x303f) || # CJK .. Yi
($ucs >= 0xac00 && $ucs <= 0xd7a3) || # Hangul Syllables
($ucs >= 0xf900 && $ucs <= 0xfaff) || # CJK Comp. Ideographs
($ucs >= 0xfe30 && $ucs <= 0xfe6f) || # CJK Comp. Forms
($ucs >= 0xff00 && $ucs <= 0xff5f) || # Fullwidth Forms
($ucs >= 0xffe0 && $ucs <= 0xffe6) ||
($ucs >= 0x20000 && $ucs <= 0x2ffff)));
}
# parse options
if ($ARGV[0] eq '-w' || $ARGV[0] eq '+w') {
$removewide = $ARGV[0] eq '-w';
shift @ARGV;
}
print STDERR <destination.bdf
Example:
bdftruncate.pl 0x3200 <6x13.bdf >6x13t.bdf
will generate the file 6x13t.bdf in which all glyphs with codes
>= 0x3200 will only be stored unencoded (i.e., ENCODING -1).
Option -w removes East Asian Wide and East Asian FullWidth characters
(default if threshold <= 0x3200), and option +w keeps them.
End
exit 1 if $#ARGV != 0;
# read threshold value from command line
$threshold = $ARGV[0];
if ($threshold =~ /^(0[xX]|U[+-]?)([0-9a-fA-F]+)$/) {
$threshold = hex($2);
} elsif (!($threshold =~ /^[0-9]+$/)) {
die("Illegal threshold '$threshold'!\n");
}
$removewide = $threshold <= 0x3200 unless defined $removewide;
# filter file
while () {
if (/^ENCODING\s+(-?\d+)/ &&
($1 >= $threshold || ($removewide && iswide($1)))) {
print "ENCODING -1\n";
} elsif (/^STARTFONT/) {
print;
print "COMMENT AUTOMATICALLY GENERATED FILE. DO NOT EDIT!\n";
printf("COMMENT In this version of the font file, all characters >= " .
"U+%04X are\nCOMMENT not encoded to keep XFontStruct small.\n",
$threshold);
} else {
s/^COMMENT\s+\"(.*)\"$/COMMENT $1/;
s/^COMMENT\s+\$[I]d: (.*)\$\s*$/COMMENT Derived from $1\n/;
print;
}
}