Is it possible to not add a node to the closed list in a pointGraph? (Image explanation inside)

General
1

Hello, is it possible to keep checking every node in a point graph by not adding it to the closed list assuming there will always be a way to get there? Also the graph would be very linear.

Why do I want this? In a railway system, you can go to one point to another, buy maybe you need to go through a closed node already checked by one of the possible directions a train can go.

The train wants to go from A to B, the A* is color green, it will search in both directions of the train at the same time and close all nodes if checked, as you see it should go through the purple path. When the a * search touches together (the “collision green wall”) it stops searching (becuase the correct path is larger) and says no path was found.

2

Hi

Ok, you have found the snag in the fix I posted in the other answer.

Due to the nature of A* and most graph searching algorithms, this might give you incorrect results in some rare cases. It might help to turn off the heuristic (A* Inspector -> Settings -> Heuristic).

The only way to solve this better is to represent a railroad track as two sequences on nodes. One sequence of nodes going in one direction, and one for the other direction.
All links between nodes should be directed, i.e A → B does not imply B → A.