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Comment by ben509 | Hacker News Reader

It is a popular algorithm, especially because it's stateless, but it only works if the maze is simply connected, so a simple loop can cause it to fail.

A simple mechanism that would also make it more interesting would be for wall following to flip handedness at random intervals. That is, the guest would start off by following the wall with his left hand, and then after some random number of steps, start following with his right hand.

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> It is a popular algorithm, especially because it's stateless, but it only works if the maze is simply connected, so a simple loop can cause it to fail.

If we’re talking about mazes where the entrance and exit are both on the perimeter wall, those points must be connected by that wall and the algorithm is guaranteed to be successful.

I think GP meant if there's an island in the middle, it won't work following that. But if you start from the entrance, it's fine.

Also, the exit or entrance shouldn't be on that island in the middle. Bridges/tunnels connecting different points will also mess it up.

It's a good algorithm within some very specific constraints.

All of those things are conveniently excluded by the architectural constraint of using live hegdes as the construction medium: the maze must be planar, and the entrance and exit need to be at the outside to allow access. You can have secondary desinations in the interior that aren’t reachable this way, though.

The hedge maze needn't be planar though, that's a faulty assumption. See Honey Pot Hill Orchard's hedge maze for a counterexample: https://www.honeypothill.com/

The trick used in the github issue cited by the other reply is a similar idea, but the change in y axis value is applied to the exit rather than throughout the maze, via a tunnel from the center.

I'm not sure exactly what you're saying here, but if you're saying that the proposed algorithm will work for all mazes in RCT2, I think you're wrong: https://github.com/OpenRCT2/OpenRCT2/pull/12546#issuecomment...

If the entrance were, the exit necessarily would be too; so it would work. (The island would be a corner of the maze, you'd just walk in, then left/right (according to hand) and out.

How does one get to the island by keeping one hand on a wall? Wouldn't an island just be equivalent to a big empty area?

As I said 'if you start from the entrance, it's fine'. The comment up thread that I interpreted that way (it wasn't my own) was in reply to a comment that sounded like you could start anywhere (e.g. attempt the maze in the right spirit and then give up and put your hand on any wall), not just at the entrance.

Very true and thanks for clarifying.

there is exactly an example of that in the github comment thread.

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