Creating maps and tileset for a 2d java game

Question

I'm not a completly beginner to java, so I decided to write a map loader and a tileset loader myself instead of using a tilemap editor like Tiled. I'm using Slick & LWJGL for my game.

The plan was to load every map and tileset from external files. When creating a new map, you'd be able to assign tilesets to your map which define the tiles used to paint the map.

I've already written a tileset loader which creates tiles from an external file. For example:

0|floor|tiles/floor.png;

is a tile where id=0, floor means the player in the game would be able to walk on that tile, tiles/floor.png is the texture of the tile.

The tiles are stored in an array in the tileset class.

But I don't know how to create the map loader. Example for a map:

1, 1, 1, 1, 1;

1, 0, 0, 0, 1;

1, 0, 2, 0, 1;

etc. The numbers symbolize the id's of the tiles.

Is there any way to realize my plans? Or is there a better way?

Thanks in advance.

PS: Sorry for my english, I'm no native speaker.

---

My current solution:

public void createTiles() {
    for(int y = 0; y < map.length; y++) {
        for(int x = 0; x < map[y].length; x++) {
            for(int i = 0; i < tileSets.length; i++) {
                for(int j = 0; j < tileSets[i].tiles.length; j++) {
                    if(map[y][x] == j) {
                        Tile tile = new Tile(tileSets[i].tiles[j].texture, x, y, xOff, yOff, tileSets[i].tiles[j].isWall);
                        tileList.add(tile);
                    }
                }
            }
        }
    }
}

Answer 1

Usually you use a 2D array of map tiles for this; and simply you assign them an ID. Then you can simply iterate over the tiles and draw the specific tile.

Usually, you can compute this similarly as such: x = tileID % tilesetWidth y = tileID / tilesetWidth;

Then, your source rectangle is simply (x, y, tileWidth, tileHeight)

Answer 2

You're on the right track! You'd want to iterate through your map (which is almost aways a 2D Array) and for each tile in the 2D Array do something similar to the pseudocode below;

for (int tileY = 0; tileY < map.length; ++tileY) {
    for (int tileX = 0; tileX < map[tileY].length; ++tileX) {
        switch (map[tileX][tileY]) {
            case 0:
                tile.setImage(someTileImage1.png);
                tile.setSomeOtherProperty(true);
                break;
            case 1:
                tile.setImage(someTileImage2.png);
                tile.setSomeOtherProperty(true);
                break;
            etc...
            default
                break;
        }
    }
}

the case statements representing each type of tile you can have in your map.

That said, it's sometimes good to be lazy (I mean that in a good way :) ). Why not make use of a great tile editor like Tiled and just setup a map loader to parse the Tiled generated XML or JSON file? You know the old saying, don't reinvent the wheel, but I can respect if you'd really like to know how exactly that wheel is created!