#!/usr/bin/perl -w

use strict;

my $input_file = $ARGV[0] || "text.bmp";

###################################################

my $buffer = '';

open(F, $input_file) or die $!;

binmode(F);

while(my $temp = <F>){$buffer .= $temp;}

close(F);

# read header

# 0  2  UINT    bfType;

# 2  4  DWORD   bfSize;

# 6  2  UINT    bfReserved1;

# 8  2  UINT    bfReserved2;

# 10 4  DWORD   bfOffBits;

my $header = substr($buffer, 0, 14);

$buffer = substr($buffer, 14);

# read info

# 0  4  DWORD   biSize;

# 4  4  LONG    biWidth;

# 8  4  LONG    biHeight;

# 12 2  WORD    biPlanes;

# 14 2  WORD    biBitCount;

# 16 4  DWORD   biCompression;

# 20 4  DWORD   biSizeImage;

# 24 4  LONG    biXPelsPerMeter;

# 28 4  LONG    biYPelsPerMeter;

# 32 4  DWORD   biClrUsed;

# 36 4  DWORD   biClrImportant;

my $info = substr($buffer, 0, 40);

my $bits = substr($buffer, 40);

my ($bitcount) = unpack('v', substr($info, 14, 2));

my ($compress) = unpack('i', substr($info, 16, 4));

my ($size_x) = unpack('i', substr($info, 4, 4));

my ($size_y) = unpack('i', substr($info, 8, 4));

unless ($bitcount == 24){

	die "can only operate on 24 bit bitmaps (this is $bitcount bit)";

}

unless ($compress == 0){

	die "can only operate on uncompressed bitmaps";

}

####################################################

my $line_shift = $size_x * 3;

$line_shift += ($size_x % 4);

print "/*Bitmap-Size: $size_x x $size_y */\n";

print "/*            |       0      ||       1      ||       2      ||       3      ||       4      ||       5      ||       6      ||       7      ||       8      ||       9      ||       :      ||     (undef)  | */\n";

my $x;

my $y;

for ($y=$size_y-1; $y >= 0; $y--) {

	printf ("/* Row %2d */ \"",($size_y - $y - 1));

	for ($x=0; $x <=$size_x-1; $x=$x+8){

		my $_8pix = 0;

		for my $subx(0..7) {

			my $offset = (($x+$subx) * 3) + ($y * $line_shift);

			my $b = ord(substr($bits, $offset+0, 1));

			my $g = ord(substr($bits, $offset+1, 1));

			my $r = ord(substr($bits, $offset+2, 1));

			unless (($r == 255) && ($g == 255) && ($b == 255)){

				$_8pix += 2 ** (7 - $subx);

			}

		}

		print "\\x";

		print "0" if ($_8pix < 16);

		printf ("%x",$_8pix);

	}

	print "\"\n";

}