A simple implementation of the astar pathfinding algorithm from red blob games as well as "Dijkstra Maps" as described in [Dijkstra Maps Visualized]https://www.roguebasin.com/index.php/Dijkstra_Maps_Visualized

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In order to use the astar pathfinder you must have a path map for it to navigate. You can define one by implementing the PathMap trait, or you can use the built-in PathMap2d.

Example

use sark_pathfinding::*;

let mut pf = Pathfinder::new();
let mut map = PathMap2d::new([10, 10]);
map.add_obstacle([3,0]);
map.add_obstacle([3,1]);
let path = pf.astar(&map, [0, 0], [5, 0]).unwrap();
assert_eq!(6, path.len());

From the "astar" example.

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A DijkstraMap can be generated using a PathMap as well. The pathmap defines the obstacles and movement costs, and the 'goals' are defined in the dijkstra map.

Example

use sark_pathfinding::*;
let mut pathmap = PathMap2d::new([20,20]);
pathmap.add_obstacle([5,5]);
pathmap.add_obstacle([5,6]);
pathmap.add_obstacle([5,7]);

// Ensure the dijsktra map is defined with  the same size as your pathmap.
let mut goals = DijkstraMap::new([20,20]);
goals.add_goal([10,10], 0.0);
goals.add_goal([15,15], 5.0);
goals.recalculate(&pathmap);
let next_step = goals.next_lowest([13,13], &pathmap).unwrap();
// Lower value goals are considered 'closer'.
assert_eq!([12,12], next_step.to_array());