Pathfinding

Pathfinding refers to the process of getting from Position A to Position B.

Pathfinder

Created by The General, the PathFinder module provides a specialized version of the Jump point search algorithm. It provides a multiroom pathfinder that performs extremely well.

This can be utilized using either the Pathfinder.search function or Room.findPath.

Costmatrixes

Each element in the world can be given a weight that affects how the Pathfinder generates it's results. Terrain based weights can be added using options, but custom weights need to be added using costmatrixes. These are classes formed off of the Pathfinder module that allow elements to be specified individually. A weight of one makes an element the most prefered, while a weight of 255 means the element is completely blocked.

Costmatrixes are not generated directly and given to the Pathfinder. Instead a callback function that takes a room name can be sent as an option, and it should return either a costmatrix or false if the room should be off limits. Depending on the needs of the program this function could add creeps, structures, and roads with different weights. It can even be used to have creeps avoid source keepers or hostiles.

To avoid the potentially expensive task of generating the costmatrix each [tick] the costmatrix class comes with serialize and deserialize functions. These can be large with a lot of redundant data, making options like lzstring potentially useful.