NAME

Math::Spiral - Perl extension to return an endless stream of X, Y offset coordinates which represent a spiral shape

SYNOPSIS

#!/usr/bin/perl -w
  
use Math::Spiral;

my $s = new Math::Spiral();
my($xo,$yo)=$s->Next();


# perl -MMath::Spiral -e '$s=new Math::Spiral(); foreach(0..9) { ($xo,$yo)=$s->Next(); $chart[2+$xo][2+$yo]=$_; } foreach $y (0..4){foreach $x(0..4){if(defined($chart[$x][$y])){print $chart[$x][$y]} else {print " ";} } print "\n"}'

DESCRIPTION

This module outputs an infinte sequence of coordinate offsets, which you can use to plot things in a spiral shape. The numbers return "clockwise"; negate one if you want to go anti-clockwise instead.

It is useful for charting things where you need to concentrate something around the center of the chart.

EXAMPLE

#!/usr/bin/perl -w
  
use Math::Spiral;

my $s = new Math::Spiral();

foreach(0..9) {
  ($xo,$yo)=$s->Next();	# Returns a sequnce like (0,0) (1,0) (1,1) (0,1) (-1,1) (-1,0) (-1,-1) (0,-1) (1,-1) (2,-1) ... etc
  $chart[2+$xo][2+$yo]=$_;
}

foreach $y (0..4) {
  foreach $x(0..4) {
    if(defined($chart[$x][$y])) { 
      print $chart[$x][$y] 
    } else {
      print " ";
    }
  }
  print "\n"
}

Prints

6789
501 
432 

EXPORT

None by default.

Notes

new

Usage is

my $s = new Math::Spiral();

Next

Returns the next x and y offsets (note that these start at 0,0 and will go negative to circle around this origin)

Usage is

my($xo,$yo)=$s->Next();
# Returns a sequnce like (0,0) (1,0) (1,1) (0,1) (-1,1) (-1,0) (-1,-1) (0,-1) (1,-1) (2,-1) ... etc (i.e. the x,y coordinates for a spiral)

AUTHOR

This module was written by Chris Drake cdrake@cpan.org

COPYRIGHT AND LICENSE

Copyright (c) 2019 Chris Drake. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.18.2 or, at your option, any later version of Perl 5 you may have available.