Precomputed-Direction Heuristics for Suboptimal Grid-Based Path-finding

This paper describes BubbleDragon, an entry in the 2012 Grid-based Path-Planning Competition. We aim to solve path-finding problems in the minimum time possible by precomputing paths from states in a region to its frontiers. Experimental results show that suboptimal paths for 1024x1024 grids can be retrieved in less than 1ms on average.