a-star

Generic synchronous A search algorithm.

Usage

``js
var aStar = require('a-star');
// if this is going to take a while you may want to child_process.fork
// and pass the results to the parent process
// see below for options
var path = aStar(options);
console.log(path);
`

Documentation

aStar(options)

$3

Returns an object that looks like this:

`js
{
status: 'success', // one of ['success', 'noPath', 'timeout']
path: [startNode, node1, node2, ..., endNode],
}
`

If status is:

* success - a path was found and path is an array of nodes including start
and end.
* noPath - there is no path from start to end. path is the path to the
closest node to end that could be found.
* timeout - no path was found in the allotted time. path is the path to
the closest node that could be found in the allotted time.

$3

* start - the start node
* isEnd - function(node) that returns whether a node is an acceptable end
* neighbor - function(node) that returns an array of neighbors for a node
* distance - function(a, b) that returns the distance cost between two
nodes
* heuristic - function(node) that returns a heuristic guess of the cost
from node to an end.
* hash - function(node) that returns a unique string for a node. this is
so that we can put nodes in heap and set data structures which are based
on plain old JavaScript objects. Defaults to using node.toString.
* timeout` - optional limit to amount of milliseconds to search before
returning null.

The data type for nodes is unrestricted.