NAME
    AI::Pathfinding::AStar - Perl implementation of the A* pathfinding
    algorithm

SYNOPSIS
      package My::Map::Package;
      use base AI::Pathfinding::AStar;

    # Methods required by AI::Pathfinding::AStar sub getSurrounding { ... }

      package main;
      use My::Map::Package;

      my $map = My::Map::Package->new or die "No map for you!";
      my $path = $map->findPath($start, $target);
      print join(', ', @$path), "\n";

DESCRIPTION
    This module implements the A* pathfinding algorithm. It acts as a base
    class from which a custom map object can be derived. It requires from
    the map object a subroutine named "getSurrounding" (described below) and
    provides to the object a routine called "findPath" (also described
    below.) It should also be noted that AI::Pathfinding::AStar defines two
    other subs ("calcF" and "calcG") which are used only by the "findPath"
    routine.

    AI::Pathfinding::AStar requires that the map object define a routine
    named "getSurrounding" which accepts an identifier of a particular node
    on your map, and returns an array reference containing the following
    details about each of the surrounding nodes:

    Node ID
    Cost to enter that node
    Heuristic
    Basically you should return an array reference like this: "return [
    [$node1, $cost1, $h1], [$node2, $cost2, $h2], [...], ...];" For more
    information on heuristics and the best ways to calculate them, visit the
    links listed in the *SEE ALSO* section below. For a very brief idea of
    how to write a getSurrounding routine, refer to the included tests.

    As mentioned earlier, AI::Pathfinding::AStar provides a routine named
    "findPath" which requires as input the starting and target node
    identifiers. The "findPath" routine does not care what format you choose
    for your node IDs. As long as they are unique, and can be recognized by
    Perl's "exists $hash{$nodeid}", then they will work. In return, this
    routine returns a reference to an array of node identifiers representing
    the least expensive path to your target node. An empty array means that
    the target node is entirely unreacheable from the given source.

PREREQUISITES
    This module requires Heap::Simple to function.

SEE ALSO
    Heap::Simple, http://www.policyalmanac.org/games/aStarTutorial.htm,
    http://xenon.stanford.edu/~amitp/gameprog.html

INSTALLATION

    To install this module type the following:

        perl Makefile.PL
        make
        make test
        make install

    To install this module into a specific directory, do:
        perl Makefile.PL PREFIX=/name/of/the/directory
    ...the rest is the same...

    Please also read the perlmodinstall man page, if available.

AUTHOR
    Aaron Dalton - aaron@daltons.ca This is my very first CPAN contribution
    and I am not a professional programmer. Any feedback you may have, even
    regarding issues of style, would be greatly appreciated. I hope it is of
    some use.

COPYRIGHT AND LICENSE
    Copyright (c) 2004 Aaron Dalton. All rights reserved. This library is
    free software; you can redistribute it and/or modify it under the same
    terms as Perl itself.