How do i initialize and use a Texture Array? LibGDX

Question

First of all, I am new to Java and LibGDX..

What I am trying to do is Load my texture images into an array so that I can reference them in my drawing code by number, rather than by name. I am drawing a tile map.

Instead of this:

tile1 = new Texture(Gdx.files.internal("grass.png"));
tile2 = new Texture(Gdx.files.internal("dirttile.png"));
tile3 = new Texture(Gdx.files.internal("watertile.png"));

I would like it to be more like:

tile[1] = new Texture(Gdx.files.internal("grass.png"));
tile[2] = new Texture(Gdx.files.internal("dirttile.png"));
tile[3] = new Texture(Gdx.files.internal("watertile.png"));

..so that later I can draw them by which tile I need..such as

tileType = worldMap[i][j]; //will be an int number
batch.draw(tile[tileType], tileX, tileY);

I can't figure out how to initialize array and load textures into it though in order to do this, without getting errors.

---

Basically I need to draw my map based on numbers I have in a tile map like this:

 int worldMap[][] = {
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,3,3,3,1,1,1,1 } ,
            { 1,1,1,3,3,3,1,1,1,1 } ,
            { 1,1,1,3,3,3,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
            { 1,1,1,1,1,1,1,1,1,1 } ,
    };

I need to draw the map tile based on the numbers in that map... 1 = grass 2 = dirt 3 = water etc.... Still no luck getting the array working.

Answer 1

You can initialize tile1, tile2 and tile3 and then you can add them to Array.

tile1 = new Texture(Gdx.files.internal("grass.png"));
tile2 = new Texture(Gdx.files.internal("dirttile.png"));
tile3 = new Texture(Gdx.files.internal("watertile.png"));

Here is how you will initialize Array:

Texture[] tile = {tile1, tile2, tile3};

Answer 2

Having a list of textures in an array is not a great idea. What if you decide to put them into a texture atlas later (which is generally more efficient than loading a bunch of files)? What if you change the order of a file in the middle? You'll have to re-order a bunch of your data.

A more flexible approach would be to keep not just a flat file name or index, but a combination of the two; perhaps in a simple class, or a hash:

class Tile {
    private String filename;
    private int index;
}

// or ...

// filename => index
Map<String, int> textureIndicies = new HashMap<String, int>(); 

In any case, about your original problem: I suggest you use a dynamic class like ArrayList here instead of a flat array. Why?

• Easier to add and remove images from it
• Easy to get the element at a particular index
• Approximately the same average runtime performance as an array

The choice is yours, though, with what approach you go with.