Fast Flash Pathfinding Example

[webgeek]

Not nextDirection, but the next tile you need to go to. The trick is that the array contains data you have to loop over an unknown number of times to get your final path. You couldn't realistically store every single path in an array as we are talking about a LOT of them. By using a 100% accurate pathfinding engine (Dijkstras in this case) then you only need to store what the next correct step should be. Make sense?

This way you are storing only gridWidth * gridHeight total pieces of data. You just use a simple algorithm to build any given path at runtime. All the hard work is done for you. In a 25x25 sized grid, you are storing 625*625 total entries (~390k). You are trading off memory usage for CPU load. For performance reasons, I keep these as raw numbers rather then a object references. It works great and is very fast and simple to implement once you get the array building properly.

The way to reduce memory load is to simply use many grids of different sizes laid on top of each other. This allows you to use small grids to get to waypoints of bigger grids.

Edit: BAD mistake on the numbers, sorry.