See a demo at http://www.briangrinstead.com/files/astar/
If you want just the A* search code (not the demo visualization), use code like this http://gist.github.com/581352
<scripttype='text/javascript'src='astar.js'></script><scripttype='text/javascript'>vargraph=newGraph([[1,1,1,1],[0,1,1,0],[0,0,1,1]]);varstart=graph.grid[0][0];varend=graph.grid[1][2];varresult=astar.search(graph,start,end);// result is an array containing the shortest pathvargraphDiagonal=newGraph([[1,1,1,1],[0,1,1,0],[0,0,1,1]],{diagonal: true});varstart=graphDiagonal.grid[0][0];varend=graphDiagonal.grid[1][2];varresultWithDiagonals=astar.search(graphDiagonal,start,end,{heuristic: astar.heuristics.diagonal});// Weight can easily be added by increasing the values within the graph, and where 0 is infinite (a wall)vargraphWithWeight=newGraph([[1,1,2,30],[0,4,1.3,0],[0,0,5,1]]);varstartWithWeight=graphWithWeight.grid[0][0];varendWithWeight=graphWithWeight.grid[1][2];varresultWithWeight=astar.search(graphWithWeight,startWithWeight,endWithWeight);// 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).
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/)
If you don't have grunt installed, follow the grunt getting started guide first.
Pull down the project, then run:
npm install
grunt