#!/usr/bin/perl -w
# Copyright 2011, 2012 Kevin Ryde
# This file is part of Math-PlanePath.
#
# Math-PlanePath 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 3, or (at your option) any later
# version.
#
# Math-PlanePath 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 Math-PlanePath. If not, see .
use 5.006;
use strict;
use warnings;
use Image::Base::PNGwriter;
use Math::PlanePath::HilbertCurve;
#use Smart::Comments;
my $width = 500;
my $height = 500;
my $image = Image::Base::PNGwriter->new (-width => $width,
-height => $height);
my $scale = 20;
sub rotate {
my ($x, $y) = @_;
return ($scale * ($x + $y) + $scale, $scale * ($x - $y) + int($height/2));
}
my $path = Math::PlanePath::HilbertCurve->new;
my ($prev_x, $prev_y) = $path->n_to_xy(0);
my ($prev_rx, $prev_ry) = rotate($prev_x, $prev_y);
foreach my $n (1 .. 64) {
my ($x, $y) = $path->n_to_xy($n);
### xy: "$x,$y"
my ($rx, $ry) = rotate($x,$y);
$image->line ($rx,$ry, $prev_rx,$prev_ry, 'white');
### line: "$rx,$ry, $prev_rx,$prev_ry"
($prev_x, $prev_y) = ($x, $y);
($prev_rx, $prev_ry) = ($rx, $ry);
}
$image->save ('/tmp/x.png');
system ('xzgv /tmp/x.png');
exit 0;