Bettern pruning rules for Jump Point Search in orthogonal mode

[Yonaba]

Jump Point Search was not actually devised for orthogonal search on uniform cost grids. It actually takes advantage of heading diagonally (over straight directions) to reach a goal.

In the actual implementation of JPS, the problem was partially solved, but not in a very elegant manner, as it floods the search with forced neighbors, jump points and discards evrey single diagonal expansion. It works fine, but the search time is a bit long (higher than standard A-star) and the return path is a step-by-step path.

The point here is to look into ways to develop a new set of pruning rules for 4-directions grids. Some starting points that might be worth investigating further or detailed articles that can be used for reference:

• Online graph pruning for pathfinding on grid maps (original paper, pdf, direct link)
• Jump Point Search (Daniel Harabor's blog)
• Jump Point Search explained (Nathan Witmer's article)
• How to speed up pathfinding with the JPS algorithm (GameDev tuts+)
• Is JPS appliable to non-diagonal grids (Ilmari Karonen's response on Gamedev StackExchange).
• Hybrid limited range JPA* in a 3D world