NAME

Algorithm::Line::Bresenham - simple pixellated line-drawing algorithm

SYNOPSIS

 use Algorithm::Line::Bresenham qw/line/;
 my @points = line(3,3 => 5,0);
    # returns the list: [3,3], [4,2], [4,1], [5,0]
 line(3,3 => 5,0,  \&draw_line);
    # calls draw_line on each point in turn

DESCRIPTION

Bresenham is one of the canonical line drawing algorithms for pixellated grids. Given a start and an end-point, Bresenham calculates which points on the grid need to be filled to generate the line between them.

Googling for 'Bresenham', and 'line drawing algorithms' gives some good overview. The code here takes its starting point from Mark Feldman's Pascal code in his article Bresenham's Line and Circle Algorithms at http://www.gamedev.net/reference/articles/article767.asp.

FUNCTIONS

line

 line ($from_y, $from_x => $to_y, $to_x);

Generates a list of all the intermediate points. This is returned as a list of array references.

 line ($from_y, $from_x => $to_y, $to_x,  \&callback);

Calls the referenced function on each point in turn. The callback could be used to actually draw the point. Returns the collated return values from the callback.

circle

    my @points = circle ($y, $x, $radius)

Returns the points to draw a circle with

TODO and BUGS

None currently.

THANKS

Patches for the circle algorithm and a float value bug contributed by Richard Clamp, thanks!

AUTHOR and LICENSE

osfameron, osfameron@cpan.org

Copyright (c) 2004-2006 osfameron. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

See http://www.perl.com/perl/misc/Artistic.html