Topic: Multi-Dimensional Arrays in AS (Page 1 of 1)

hi all,
Motivated by the 20 liner compeition in the DHTML/JS forum i've set about trying to create my own landscape/heighfield rotater thing. I come from a C programming background and i thought it'd be pretty easy to just attach a load of movie clips to the stage and put them all (well references to them) into a 2d array so i could call back to them with ease for the moving and the jiggery pokery.

This is what i think sets up a 2d array called point_set, pretty strange syntax a mon avis...

point_set = new Array;

point_set = [[],[]];

then as i attach the clips i do this:

vertex = attachMovie("mcPoint", "n"+total, total);

		point_set[[i],[j]] = vertex;

where total is just a simple counter var.

So far so good, but when i try and use the old nested for loops to actually reference parts of point_set, like this:

onEnterFrame = function()

{



	for (j=0; j<height; j++)

	{

		for (i=0; i<width; i++)

		{

			node = point_set[[i],[j]];

                       // rest of the function...

i only manage to get teh end five. The concept of the end is a bit weird due to the screen co-ords being annoyingly offset instead of nice carteisan.

The .fla is here, its not very elegant so far but you never know. The actual rotation is pretty amusing too, still i should be able to sort that out.

I've never coded an ActionScript myself, but I'm I thought the syntax for multi-dimensionnal arrays in AS was the same as in JS, C, C++, ... that is :

node = point_set[ [], [] ]

	for (j=0; j<height; j++)

	{

		for (i=0; i<width; i++)

		{

			node = point_set[[i],[j]];

                       // rest of the function...

		}

	}

Are you sure, that the fact that you can access the last 5 items is not due to the fact that Flash allows the use of a "bastardized" syntax that actually only let you access the first item ( sub-array ) of the first dimension of your array ?

Just my 0.02?

I think your syntax is close but not quite there.
I think it should be node=point_set[i][j];

in other words, the "j" element of the "i" element of the array "point_set".

You might still use the [[...],[...]]; syntax to create the multidimensional array, but not to refer to a specific value in the set.

Poi's right to suppose that it's essentially the same as JavaScript, since they share a common ECMAScript lineage.

Take a glance at
http://www.macromedia.com/support/flash/ts/documents/twodarray.htm
and
http://actionscript-toolbox.com/arrayobject2.php

Gosh! I should write code after a 4hours sleep and a full day of work. I obvsiouly thought node=point_set[ i ][ j ]; to access the elements of the array and sub arrays



(Edited by poi on 07-13-2004 10:13)

yeah well i think i was writing it like that, i assumed that was how it worked just from c knowledge. but i think i was trying to create the array by like:

Array1 = new ARRAY;

Array1 = [][];

and it didn't like that at all, i guess i moved to what seemed to be the correct syntax not thinking it would be a mix. Oh how complicated these 'new' languages are.

THanks for the help guys.

yeah well i think i was writing it like that, i assumed that was how it worked just from c knowledge. but i think i was trying to create the array by like:

Array1 = new ARRAY;

Array1 = [][];

and it didn't like that at all, i guess i moved to what seemed to be the correct syntax not thinking it would be a mix. Oh how complicated these 'new' languages are.

THanks for the help guys.