Difference between revisions of "Jumper"

(Jumper)
 
(Updated Snippet (1.8.0 release))
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== Technical notes ==
 
== Technical notes ==
  
Jumper implements the [http://harablog.wordpress.com/2011/09/07/jump-point-search/ Jump Point Search] algorithm (tight along with [http://www.aiwisdom.com/ai_astar.html A-star] running on the background). It also implements a lighter implementation binary heaps module to maintain its open list of nodes while performing a search.
+
Jumper implements a lots if search algorithms: A-star, Dijkstra, Breadth-First search, Depth First search and Jump Point search (the fastest amongst all).
  
A benchmark program running in console is available on [https://github.com/Yonaba/Jumper-Benchmark Github]. It features a set of 132 maps from the [http://movingai.com/GPPC/ 2012 Grid-based Path Planning Competition]. You might want to try this program to witness the performance of ''Jump Point Search algorithm''.
+
A benchmark program running in console is available on [https://github.com/Yonaba/Jumper-Benchmark Github]. It features a set of 132 maps from the [http://movingai.com/GPPC/ 2012 Grid-based Path Planning Competition].  
  
  
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<source lang="lua">
 
<source lang="lua">
-- A collision map.
+
-- Usage Example
-- We assume here that 0 represents walkable tiles
+
-- First, set a collision map
 
local map = {
 
local map = {
  {0,0,0,0,0},
+
    {0,1,0,1,0 },
  {0,0,1,0,0},
+
    {0,1,0,1,0 },
  {0,0,1,0,0},
+
    {0,1,1,1,0 },
  {0,0,1,0,0},
+
    {0,0,0,0,0 },
  {0,0,0,0,0},
 
 
}
 
}
 +
-- Value for walkable tiles
 +
local walkable = 0
 +
 +
-- Library setup
 +
local Grid = require ("jumper.grid") -- The grid class
 +
local Pathfinder = require ("jumper.pathfinder") -- The pathfinder lass
 +
 +
-- Creates a grid object
 +
local grid = Grid(map)
 +
-- Creates a pathfinder object using Jump Point Search
 +
local myFinder = Pathfinder('JPS', grid, walkable)
  
local walkable = 0
+
-- Define start and goal locations coordinates
local Jumper = require ('Jumper') -- Calls the library
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local startx, starty = 1,1
 +
local endx, endy = 5,1
  
-- We init our pathfinder instance, passing it the map,  
+
-- Calculates the path, and its length
-- and defining what are the walkable tiles
+
local path, length = myFinder:getPath(startx, starty, endx, endy)
local pathfinder = Jumper(map,walkable)
+
if path then
 +
  print(('Path found! Length: %.2f'):format(length))
 +
    for node, count in path:iter() do
 +
      print(('Step: %d - x: %d - y: %d'):format(count, node.x, node.y))
 +
    end
 +
end
  
-- Gets the path from location (1,1) to location (5,5)
+
--> Output:
local path, length = pathfinder:getPath(1,1,5,5)
+
--> Path found! Length: 8.83
 +
--> Step: 1 - x: 1 - y: 1
 +
--> Step: 2 - x: 1 - y: 3
 +
--> Step: 3 - x: 2 - y: 4
 +
--> Step: 4 - x: 4 - y: 4
 +
--> Step: 5 - x: 5 - y: 3
 +
--> Step: 6 - x: 5 - y: 1
 
</source>
 
</source>
  

Revision as of 08:57, 26 January 2013



What's this ?

Jumper is a pathfinding library designed for uniform-cost 2D grid-based games. It aims to be lightning fast and lightweight. It also features a clean public interface with chaining features which makes it very friendly and easy to use.


Technical notes

Jumper implements a lots if search algorithms: A-star, Dijkstra, Breadth-First search, Depth First search and Jump Point search (the fastest amongst all).

A benchmark program running in console is available on Github. It features a set of 132 maps from the 2012 Grid-based Path Planning Competition.


Usage

Jumper is easy to use. Here is a basic example using the latest version available.

-- Usage Example
-- First, set a collision map
local map = {
    {0,1,0,1,0 },
    {0,1,0,1,0 },
    {0,1,1,1,0 },
    {0,0,0,0,0 },
}
-- Value for walkable tiles
local walkable = 0

-- Library setup
local Grid = require ("jumper.grid") -- The grid class
local Pathfinder = require ("jumper.pathfinder") -- The pathfinder lass

-- Creates a grid object
local grid = Grid(map) 
-- Creates a pathfinder object using Jump Point Search
local myFinder = Pathfinder('JPS', grid, walkable) 

-- Define start and goal locations coordinates
local startx, starty = 1,1
local endx, endy = 5,1

-- Calculates the path, and its length
local path, length = myFinder:getPath(startx, starty, endx, endy)
if path then
  print(('Path found! Length: %.2f'):format(length))
    for node, count in path:iter() do
      print(('Step: %d - x: %d - y: %d'):format(count, node.x, node.y))
    end
end

--> Output:
--> Path found! Length: 8.83
--> Step: 1 - x: 1 - y: 1
--> Step: 2 - x: 1 - y: 3
--> Step: 3 - x: 2 - y: 4
--> Step: 4 - x: 4 - y: 4
--> Step: 5 - x: 5 - y: 3
--> Step: 6 - x: 5 - y: 1

Jumper offers a lot more options to customize the pathfinding behavior. Please, kindly check out the Readme to figure them out.


Feedback

If you have any question, proposal, idea to improve, or if you are just using Jumper in a project, I would love to hear your feedback. Issues/suggestions can be posted on the project issue tracker on Github, or by e-mail.


Links