Question

I’m implementing a version of the A* path-finding algorithm in Javascript. To preserve my sanity, I’m using a pseudo-multi-dimensional array (i.e. nested arrays). If you aren’t familiar with A*, one step is checking the surrounding nodes of an “open” node.

How can I pass the location of the “open” node and check adjacent nodes in my array? Shouldn’t array locations be first-class?

function checknode (node) //Such as [5,2]
{
     if(array[node+1][node]==something) //In this case [6,2]

}

Yeah, I know I could pass the x and y coordinates as seperate arguments, like so:

function checknode (nodex, nodey)
{
     if(array[nodex+1][nodey]==something)
}

But the implications this has as far as my code is concerned is undesirable.

EDIT: Basically, I’m wondering if the location of an item of an array (5,2) can be passed into my function and manipulated.

Answer 1

You can make a composite value (using an object) that contains the two coordinates. That way you can pass it as a single parameter:

function checknode(node) {
  if (array[node.x + 1][node.y] == something) //In this case [6,2]
}

Example call:

checknode({ x: 5, y: 2 });