Working with Objects

• Object Types
• Tile Objects
• Text Objects
  • Text Object Attributes
• Point Objects
  • Custom Point Objects
• Dynamics

By default, vector objects are not shown when rendered in SKTiled. To enable them, set the SKTilemap.showObjects global attribute. This override has the advantage of allowing you to work in your Tiled scene with objects visible, but not see them in your game view. Note that the SKTilemap.showObjects property does not change the visibility of object groups, but rather affects the objects themselves. Text and tile objects are exempt from this function.

The SKTileObject class represents a vector object in a object group layer. SKTiled renders all Tiled object types:

• Rectangle
• Ellipse
• Polygon
• Polyline
• Point

SKTileObject objects are subclasses of SKShapeNode. Each object stores an array of points from which the path is drawn.

Object Type Property

Objects assigned a type in Tiled will retain that property in SKTiled, accessed with the optional SKTileObject.type property:

Objects assigned a type property can be queried from the parent SKObjectGroup, or the SKTilemap node:

// query objects from the layer
let emitterObjects = objectsGroup.getObjects(ofType: "Emitter")

// query objects from the map node
let allEmitterObjects = tilemap.getObjects(ofType: "Emitter", recursive: true)

The recursive argument is optional in both instances, and enabling it will search all object layers in the map, including nested layers.

Tile Objects

Tile objects are special object types that contain an optional globalID value. The corresponding tile texture(s) are rendered within the object’s bounding shape. Tile objects are

Objects added via the Insert Tile tool in Tiled will render as SKTileObject objects. You can also create a tile object manually via the SKObjectGroup.newTileObject(data:) method:

// add a tile object for global id 23
if let tileData = tilemap.getTileData(globalID: 23) {
    if let tileObject = objectGroup.newTileObject(data: tileData) {
        tileObject.position = objectGroup.pointForCoordinate(10, 5)
    }
}

If the tile data contains animated frames, the resulting object will also render as animated.

Text Objects

Text objects are objects that render text within the bounding shape. Basic formatting properties are supported via the TextObjectAttributes property. To change the text on the fly, all you need to do is change the object’s text property. The object will redraw automatically.

There are several ways to query text objects:

if let scoreObject = objectGroup.getObjects(withText: "SCORE").first {
    // update the rendered text
    scoreObject.text = "2000"
}

If you intend to update the text object dynamically, be mindful to draw the object in Tiled to the appropriate size to avoid text clipping.

Text Object Attributes

By default, text object attributes are translated from Tiled*. It is possible to change the text attributes via the SKTileObject.textAttributes property.

textObject.textAttributes.fontName = "Courier"
textObject.textAttributes.fontSize = 16
textObject.textAttributes.fontColor = .white
textObject.textAttributes.alignment.horizontal = .center

* text wrap attribute not currently supported.

Point Objects

Point objects are a special object type that represents a single point in the map. As such, it has no shape parameters and is really only useful as a reference point or an anchor for other nodes.

Custom Point Objects

The TilemapDelegate.customNodeForPointObject protocol method allows you to substitute a custom SKNode type for point objects matching a given type:

@objc public func customNodeForPointObject(ofType: String,
                                          attributes: [String : String],
                                          inLayer: String?) -> SKNode? {
    if (ofType == "light") {
        let light = SKLightNode()
        if let lightColor = attributes["lightColor"] {
            light.lightColor = SKColor(hexString: lightColor)
            return light
        }
    }
    return nil
}

The original point object is destroyed, but any custom attributes will be passed to this method, allowing you to map them to your custom objects.

Dynamics

You also have the option of enabling physics for each object, allowing them to react as dynamics bodies in your scene. Passing properties from Tiled allows you to easily create dynamic objects in your scenes. Here, a simple scene with one object group and five objects is loaded:

• shape objects are assigned a property of isDynamic = true
• floor objects are assigned a property of isCollider = true
• map properties contain a yGravity value of -9.8

Next: Tiled Properties - Index