Add bundle

src/play_clj/core.clj

@@ -27,7 +27,7 @@
            [com.badlogic.gdx.scenes.scene2d.utils ActorGestureListener Align
             ChangeListener ClickListener DragListener FocusListener]
            [com.badlogic.gdx.utils ScreenUtils Timer$Task]
-           [play_clj.entities ShapeEntity]))
+           [play_clj.entities BundleEntity ShapeEntity]))
 
 (load "core_basics")
 (load "core_cameras")

src/play_clj/core_utils.clj

@@ -7,6 +7,16 @@
   [& body]
   `(app! :post-runnable (fn [] ~@body)))
 
+(defn bundle
+  "Returns an entity containing other entities. This is a useful way to keep
+related entities together. They will be drawn in the order they appear in the
+internal :entities vector.
+
+    (bundle (shape :filled) (texture \"image.png\"))
+    (assoc (bundle) :entities [])"
+  [& entities]
+  (BundleEntity. entities))
+
 (defn screenshot!
   "Captures a screenshot and either returns it as a `pixmap` or saves it to the
 specified path.

src/play_clj/entities.clj

@@ -73,3 +73,8 @@
     (.begin object type)
     (draw!)
     (.end object)))
+
+(defrecord BundleEntity [entities] Entity
+  (draw-entity! [{:keys [entities]} screen batch]
+    (doseq [e entities]
+      (draw-entity! e screen batch))))