xwords/xwords4/dawg/pbitm2bin.pl

87 lines
2.3 KiB
Perl
Executable file

#!/usr/bin/perl
#
# Copyright 2001 by Eric House (xwords@eehouse.org). All rights reserved.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
#
# Given a pbitm on stdin, a text bitmap file where '#' indicates a set
# bit and '-' indicates a clear bit, convert into binary form (on
# stdout) where there's one bit per bit plus a byte each for the width
# and height. Nothing for bitdepth at this point. And no padding: if
# the number of bits in a row isn't a multiple of 8 then one byte will
# hold the last bits of one row and the first of another.
use strict;
my $nRows = 0;
my $nCols = 0;
my $bits = ""; # save the chars in a single string to start
# first gather information and sanity-check the data
while (<>) {
chomp;
my $len = length();
if ( $nCols == 0 ) {
$nCols = $len;
} else {
die "line of inconsistent length" if $nCols != $len ;
}
if ( $nCols == 0 ) {
last;
}
$bits .= $_;
++$nRows;
}
my $len = length($bits);
print pack( "C", $nCols );
# if we've been given an empty file, print out a single null byte and
# be done. That'll be the convention for "non-existant bitmap".
if ( $len == 0 ) {
exit 0;
}
print pack( "C", $nRows );
printf STDERR "emitting %dx%d bitmap\n", $nCols, $nRows;
my @charlist = split( //,$bits);
my $byte = 0;
for ( my $count = 0; ; ++$count ) {
my $ch = $charlist[$count];
my $bitindex = $count % 8;
$ch == '-' || $ch == '#' || die "unknown char $ch";
my $bit = ($ch eq '#')? 1:0;
$byte |= $bit << (7 - $bitindex);
my $lastPass = $count + 1 == $len;
if ( $bitindex == 7 || $lastPass ) {
print pack( "C", $byte );
if ( $lastPass ) {
last;
}
$byte = 0;
}
} # for loop