![\"\"](\"http:\/\/www.pixnbgames.com\/blog\/wp-content\/uploads\/2017\/11\/Captura-de-pantalla-2017-11-22-a-las-23.20.38-1024x612.png\")
<\/p>\n
Now supose the main character is walking on the scene. One of the things we have to do is to detect collides with the scene. A simple approach to do it could be to check whether the position the character is occupied by a tile or it’s empty. The problem of doing it with our example is that we have in the same layer the elements which the character would collide with (ground, water), and other decoration elements which wouldn’t collide with character (bush, house). So if we use this approach to detect collisions, the character will also collide with the decoration elements.<\/p>\n
A solution to the posed issue is to split our scene in several layers: a main layer with the colliding elements, and as much layers as needed to decorate the scene.<\/p>\n
![\"\"](\"http:\/\/www.pixnbgames.com\/blog\/wp-content\/uploads\/2017\/11\/map_layers.png\")
<\/p>\n
Furthermore…<\/h4>\n
I have pointed the collision detection as the problem of using a single layer, but this has not be like this, because we can use another collision system (hardness map, physics engine, …). Nevertheless, other advantage we get using several layers better organization of our project resources or assets<\/em>. We can have decoration tileset that we can use on several maps, although the main tileset of the scene changes, for example.<\/p>\n Next we will see how to use several layers and tilesets in our game scene maps.<\/p>\n <\/p>\n To continue with the example, I will create a second tileset, with tiles of 16×16 pixels, where I will draw som aditional decoration elements. This file is called decoration.png<\/em><\/strong>, and it’s stored on the same path of the map. This is the decoration.png<\/em> tileset:<\/p>\n <\/p>\n Next, we make the following changes on the map level.tmx<\/em>:<\/p>\n This is the result after modifications:<\/p>\n All used layers are \u00abTile layers<\/em>\u00ab, that allows us to draw the scene from the tilesets.<\/p>\n As libGDX<\/em> official doc says, we can use many layers as we need, but on each layer we only use one tileset<\/strong>. If not, the drawing performance will decrease a lot.<\/p>\n <\/p>\n To follow with the example, you can use the project we create on the previous article<\/a> or you can create a new project. In my caso, I will clone the project using my cloning tool<\/a>:<\/p>\n <\/p>\n libGDX<\/em> give us functions to handle and draw whole maps, and also to do it for one or more isolated layers.<\/p>\n To get the layers of a map, we can use its name or its index of the layers list (first index is 0). The class that represents a layer created with Tiled Map Editor<\/em> is The layer which contains the ground (\u00abterrain<\/em>\u00ab) will be stored in an When working with layer’s indices, the order of the elements in the array matters. This is, the order in the array establishes the drawing order of the layers<\/em>. In this caso, when the array Layers drawing, same to map drawing, is made with an object of the class Seeing the method At last, say that decoration layers are drawed before terrain layer so that the terrain layer is over the decoration.<\/p>\n <\/p>\n You can get the example project from my GitHub<\/em> repository<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":" I will explain in this post why and how to use several layers on our maps. It’s a bit long post, so I will try to organize concepts in a clear way. If you have any doubt or suggestion, use Seguir leyendo How to use libGDX + Tiled: several layers<\/span>Several tilesets<\/h3>\n
![\"\"](\"http:\/\/www.pixnbgames.com\/blog\/wp-content\/uploads\/2017\/11\/background.png\")
<\/p>\nModifying map<\/h3>\n
\n
![\"\"](\"http:\/\/www.pixnbgames.com\/blog\/wp-content\/uploads\/2017\/11\/Captura-de-pantalla-2017-11-26-a-las-22.14.15-1024x531.png\")
<\/p>\nKeep in mind<\/h4>\n
Crate a new project<\/h3>\n
![\"\"](\"http:\/\/www.pixnbgames.com\/blog\/wp-content\/uploads\/2017\/11\/clonar-proyecto-1024x465.png\")
<\/p>\nHandling layers in libGDX<\/h3>\n
Getting layers<\/h4>\n
TiledMapTileLayer<\/code>. In this example we will use these two methods.<\/p>\nTiledMapTileLayer<\/code> object, because this will be usefull to work with it in the future. On the other hand, for the rest of layers we use an array of integers called decorationLayersIndices<\/code>, where we set the indices of the layers \u00abdecoration<\/em>\u00bb and \u00abbackground<\/em>\u00ab.<\/p>\n...\r\npublic class MyGdxTiledGame extends ApplicationAdapter {\r\n ...\r\n private TiledMap map;\r\n private TiledMapTileLayer terrainLayer;\r\n private int[] decorationLayersIndices;\r\n ...\r\n @Override\r\n public void create () {\r\n ...\r\n \/\/ Reading map layers\r\n MapLayers mapLayers = map.getLayers();\r\n terrainLayer = (TiledMapTileLayer) mapLayers.get(\"terrain\");\r\n decorationLayersIndices = new int[] {\r\n mapLayers.getIndex(\"decoration\"),\r\n mapLayers.getIndex(\"background\")\r\n };\r\n ...\r\n }\r\n ...\r\n}\r\n<\/pre>\ndecorationLayersIndices<\/code> is drawed, first is drawed the \u00abdecoration<\/em>\u00bb layer and then the \u00abbackground<\/em>\u00bb layer over the first one.<\/p>\nDrawing layers<\/h4>\n
OrthogonalTiledMapRenderer<\/code>. See how to do it<\/p>\npublic class MyGdxTiledGame extends ApplicationAdapter {\r\n ...\r\n private OrthogonalTiledMapRenderer renderer;\r\n ...\r\n @Override\r\n public void create () {\r\n ...\r\n \/\/ Instantiation of the render for the map object\r\n renderer = new OrthogonalTiledMapRenderer(map);\r\n }\r\n\r\n @Override\r\n public void render () {\r\n \/\/ Clear screen\r\n Gdx.gl.glClearColor(.5f, .7f, .9f, 1);\r\n Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);\r\n\r\n \/\/ Update the camera\r\n camera.update();\r\n renderer.setView(camera);\r\n \r\n \/\/ Rendering\r\n renderer.render(decorationLayersIndices);\r\n renderer.getBatch().begin();\r\n renderer.renderTileLayer(terrainLayer);\r\n renderer.getBatch().end();\r\n }\r\n ...\r\n}\r\n<\/pre>\nImportant<\/h4>\n
render()<\/code> of the example, we can see differences between draw a TiledMapTileLayer<\/code> object and draw layer using its indices. In case of the TiledMapTileLayer<\/code> object its needed to start the drawing batch before to draw, and end the batch at finish drawing.<\/p>\nSource code<\/h3>\n