Move viewport management down into the engine and add suitable events. Cache initial...

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

diff --git a/koperkapel/scenes/base.py b/koperkapel/scenes/base.py
index 9bad13cd9f03b9e1d172c9c977ae575002a51c88..c6b8752d41de58893a8ac3174ace3f2b37b5c284 100644 (file)
--- a/koperkapel/scenes/base.py
+++ b/koperkapel/scenes/base.py
@@ -18,6 +18,7 @@ class Engine:
     def __init__(self, app, scene):
         self._app = app
         self._scene = scene
+        self._viewport = (0, 0)
 
     def _apply_events(self, events):
         if not events:
@@ -30,12 +31,20 @@ class Engine:
         self._scene = scene
         self._scene.enter()
 
+    def quit_game(self):
+        from pgzero.game import exit
+        exit()
+
+    def move_screen(self, offset):
+        self._viewport = (self._viewport[0] + offset[0],
+                            self._viewport[1] + offset[1])
+
     @apply_events
     def update(self, dt):
         return self._scene.update(dt)
 
     def draw(self):
-        self._scene.draw(self._app.screen)
+        self._scene.draw(self._app.screen, self._viewport)
 
     @apply_events
     def on_mouse_down(self, pos, button):
@@ -77,9 +86,43 @@ class ChangeSceneEvent(Event):
     ENGINE_METHOD = "change_scene"
 
 
+class QuitEvent(Event):
+    """ Quit the game. """
+
+    ENGINE_METHOD = "quit_game"
+
+
+class MoveViewportEvent(Event):
+    """ Change to a new scene. """
+
+    ENGINE_METHOD = "move_screen"
+
+
+class Actors:
+    """ A list of actors. """
+
+    def __init__(self):
+        self._actors = []
+
+    def add(self, actor):
+        self._actors.append(actor)
+        return actor
+
+    def remove(self, actor):
+        self._actors.remove(actor)
+        return actor
+
+    def draw(self, screen):
+        for actor in self._actors:
+            actor.draw()  # TODO: allow an option screen to be passed in
+
+
 class Scene:
     """ Base class for scenes. """
 
+    def __init__(self):
+        self.actors = Actors()
+
     def enter(self):
         pass
 
@@ -89,8 +132,9 @@ class Scene:
     def update(self, dt):
         pass
 
-    def draw(self, screen):
-        pass
+    def draw(self, screen, viewport):
+        screen.clear()
+        self.actors.draw(screen)
 
     def on_mouse_down(self, pos, button):
         pass