pathfind

A pure clojurescript implementation of the A* algorithm.

Overview

Supports an arbitrary 2D grid. Obstructed cells are seen by constructing a function to pass in, passable?, which is called and passed a tuple containg the x, y coordinate being tested.

A* is called passing in this function, along with start and end coordinate tuple. This A* function returns a sequence of positions that represent the parth from start to end.

Optionally a keyword can be added to the call :cut-corners to enable the path finder to cut directly across diagonal obstacles. Default is to not cut corners.

Example

(require '[pathfind.core :as pf]
	     '[cljs.test :refer-macros [is]])

(let [passable? (fn [pos]
                    (-> pos
					    #{[3 3] [3 4] [4 4] [4 3]}
						boolean not))]
    (is (= (pf/A* passable? [0 0] [10 5])
           '([0 0] [1 1] [2 2]
             [3 2] [4 2] [5 2]
             [6 3] [7 4] [8 5]
             [9 5] [10 5]))))

Tests

lein cljsbuild test

Setup

To get an interactive development environment run:

lein figwheel

and open your browser at localhost:3449. This will auto compile and send all changes to the browser without the need to reload. After the compilation process is complete, you will get a Browser Connected REPL. An easy way to try it is:

(js/alert "Am I connected?")

and you should see an alert in the browser window.

To clean all compiled files:

lein clean

To create a production build run:

lein do clean, cljsbuild once min

And open your browser in resources/public/index.html. You will not get live reloading, nor a REPL.

License

Copyright © 2016 Crispin Wellington

Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.