xTrek: An Influence-Aware Technique for Dijkstra’s and A Pathfinders

Figure 6

Finding a path (in black) from the top-left node to the bottom-right node of a 50 × 50 grid using influence-aware algorithm (T): (a) without attractors and repulsors, the search space only covers neutral nodes (in cyan) along or close to the path (in black); (b) with 2 attractors, the search space substantially reduces itself to neutral nodes (in cyan) along the path and attractor nodes (in red-to-yellow blended with cyan) provided that they are on the way to the goal node; (c) with 2 repulsors, the search space also substantially reduces itself to neutral nodes (in cyan) along the path, as the interior nodes of repulsors were not visited; (d) with 2 attractors and 2 repulsors, the search space is again limited to neutral nodes (in cyan) and attractor nodes (in red-to-yellow blended with cyan) along the path, with repulsor nodes (in purple blue) not being visited. Nodes in cyan or blended with cyan represent visited nodes, that is, nodes in the open and closed lists.

(a)

(b)

(c)

(d)