Merge branch 'master' of ctpug.org.za:koperkapel

[koperkapel.git] / koperkapel / scenes / base.py

diff --git a/koperkapel/scenes/base.py b/koperkapel/scenes/base.py
index d0b9a951ae16c57e20e279560f54fd9ab8a7b7a4..47891a6582784613cf4f12ae81415e32be097d53 100644 (file)
--- a/koperkapel/scenes/base.py
+++ b/koperkapel/scenes/base.py
@@ -109,34 +109,61 @@ class MoveViewportEvent(Event):
     ENGINE_METHOD = "move_screen"
 
 
+class Layer:
+    """ A single layer of actors. """
+
+    def __init__(self, name):
+        self.name = name
+        self.actors = []
+
+    def __iter__(self):
+        return iter(self.actors)
+
+    def __getitem__(self, i):
+        return self.actors[i]
+
+    def __len__(self):
+        return len(self.actors)
+
+    def add(self, actor):
+        self.actors.append(actor)
+        return actor
+
+    def remove(self, actor):
+        self.actors.remove(actor)
+        return actor
+
+
 class Actors:
-    """ A list of actors.
+    """ Layers of actors.
 
     Actors may be rendered in different layers. Layers with lower levels
     are rendered lower than layers with higher ones.
     """
 
     def __init__(self):
-        self._layer_order = []
+        self._ordered_layers = []
         self._layers = {}
         self.add_layer("default", 0)
 
+    def __getattr__(self, name):
+        return self._layers[name]
+
     def add_layer(self, name, level):
-        self._layer_order.append((level, name))
-        self._layer_order.sort()
-        self._layers[name] = []
+        layer = self._layers[name] = Layer(name)
+        self._ordered_layers.append((level, name))
+        self._ordered_layers.sort()
+        return layer
 
     def add(self, actor, layer="default"):
-        self._layers[layer].append(actor)
-        return actor
+        return self._layers[layer].add(actor)
 
     def remove(self, actor, layer="default"):
-        self._layers[layer].remove(actor)
-        return actor
+        return self._layers[layer].remove(actor)
 
     def draw(self, screen):
-        for lvl, layer in self._layer_order:
-            for actor in self._layers[layer]:
+        for lvl, name in self._ordered_layers:
+            for actor in self._layers[name]:
                 actor.draw()  # TODO: allow an option screen to be passed in