javascript-astar
An implementation of the A* Search Algorithm in JavaScript
See a demo at http://www.briangrinstead.com/files/astar/
Sample Usage
If you want just the A* search code (not the demo visualization), use code like this http://gist.github.com/581352
<script type='text/javascript' src='astar.js'></script><script type='text/javascript'> var graph = 1111 0110 0011 ; var start = graphgrid00; var end = graphgrid12; var result = astar; // result is an array containing the shortest path var graphDiagonal = 1111 0110 0011 diagonal: true ; var start = graphDiagonalgrid00; var end = graphDiagonalgrid12; var resultWithDiagonals = astar; // Weight can easily be added by increasing the values within the graph, and where 0 is infinite (a wall) var graphWithWeight = 11230 04130 0051 ; var startWithWeight = graphWithWeightgrid00; var endWithWeight = graphWithWeightgrid12; var resultWithWeight = astar; // resultWithWeight is an array containing the shortest path taking into account the weight of a node</script>
A few notes about weight values:
- A weight of 0 denotes a wall.
- A weight cannot be negative.
- A weight cannot be between 0 and 1 (exclusive).
- A weight can contain decimal values (greater than 1).
Original (slower) implementation
The original version of the algorithm used a list, and was a bit clearer but much slower. It was based off the original blog post. The code is available at: https://github.com/bgrins/javascript-astar/tree/0.0.1/original-implementation.
The newest version of the algorithm using a Binary Heap. It is quite faster than the original. http://www.briangrinstead.com/blog/astar-search-algorithm-in-javascript-updated Binary Heap taken from http://eloquentjavascript.net/appendix2.html (license: http://creativecommons.org/licenses/by/3.0/)
Running the test suite
If you don't have grunt installed, follow the grunt getting started guide first.
Pull down the project, then run:
npm install
grunt