Pathfinding.js – Visualizations and Playground | Hacker News Reader

Pathfinding.js – Visualizations and Playground

qiao.github.io

186 pointsmromnia20 comments

and then there's this awesome thing:

https://anvaka.github.io/ngraph.path.demo/

If anyone has a tougher path planning problem and needs a better heuristic, I wrote an article a few years ago that might help: http://razorcode.net/articles/vehicle-path-planning.html

Thanks for writing this article! Would you mind if I share it in WeeklyRobotics(https://weeklyrobotics.com/) next week?

Feel free, it exists to be read. And you just gained a subscriber.

This is a very useful tool and helped me understand Jump Point Search for a hobby project, which as it turns out is significantly faster than A* for certain use cases.

Are there any path finding algorithms for orthogonal grids optimized for frequent changes in the environment, particularly moving opponents in a game where you can't predict their next move with certainty? A* and friends do well at finding shortest paths between a start and a goal, but what if the obstacles change after you start along that path?

How does this A* work. It seems almost "intelligent"!!

It just keeps exploring locations adjacent to locations it's already explored.

It chooses the next location by whatever one has the lowest "length of best known path to get there + estimate for distance to goal". The estimate for distance to goal is usually something like "distance as the crow flies".

Here's a fantastic intro from Red Blob Games: https://www.redblobgames.com/pathfinding/a-star/introduction...

I was surprised at how much slower the Jump Point Search variants were than vanilla A-star. I thought it was meant to be an order-of-magnitude optimisation over A-star?

Also, any idea what the 'Trace' algorithm at the bottom is? It seems significantly faster/more efficient than the others but I can't find it in the github repo and the live version of the library is minified.

Edit: Ugh, how do I escape an asterisk? >.<

This is so fun, wasted probably 30 min building mazes.

Several years old, but still awesome.

Does anyone know what the "Trace" algorithm does? I can't find anything on Google.

The last commit on the repo https://github.com/qiao/PathFinding.js/blob/master/visual/in...

says "Remove Trace finder as it is the same as BestFirstFinder"

For me it hangs on IDA*

otherwise mighty well done!

Ideas to add:

- a short description of the algorithm

- zoom out

+ knight tour

It's not hanging, it just takes a bit before it gets going. I had to wait about 30 seconds before the IDA* visualization started running.

Also thought IDA* hanged. An indicator indicating initialization would be helpful (didn't see one).

Indicators that indicate are of the best kind.

Joke aside: kudos on turning a perceived frustration into a feature fix. I wouldn't have thought about that.

Look, I was merely trying to give the author more information by verifying your observation. Your remark to me seems reasonable only if the author can see how many upvotes/downvotes a certain comment has. I don't know if he can.

A faster way to find paths on grids http://mikolalysenko.github.io/l1-path-finder/www/

This is a great demo !!! Very interesting. It allowed me to select the appropriate algorithm for a specific purpose.

I love this, useful for teaching purposes!

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