Design of Heuristics Using Vertex Information in a Grid-based Map

Title & Authors
Design of Heuristics Using Vertex Information in a Grid-based Map
Kim, Ji-Hyui; Jung, Ye-Won; Yu, Kyeon-Ah;

Abstract
As computer game maps get more elaborate, path-finding by using $\small{A^*}$ algorithm in grid-based game maps becomes bottlenecks of the overall game performance. It is because the search space becomes large as the number of nodes increases with detailed representation in cells. In this paper we propose an efficient pathfinding method in which the computer game maps in a regular grid is converted into the polygon-based representation of the list of vertices and then the visibility information about vertices of polygons can be utilized. The conversion to the polygon-based map does not give any effect to the real-time query process because it is preprocessed offline. The number of visited nodes during search can be reduced dramatically by designing heuristics using visibility information of vertices that make the accuracy of the estimation enhanced. Through simulations, we show that the proposed methods reduce the search space and the search time effectively while maintaining the advantages of the grid-based method.
Keywords
Path-finding;Heuristics for $\small{A^*}$ algorithm;Grid-based maps;
Language
Korean
Cited by
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