X-Git-Url: https://git.ctpug.org.za/?a=blobdiff_plain;f=koperkapel%2Fscenes%2Fbase.py;h=aa30be492baa518327975e8d5a96377dc88e3935;hb=4e59ab6a38bba2eccd59cee633dc4fd391c12100;hp=859f816e6359249e8dfbdc61e36f24b4699fcc44;hpb=8631d4fcb6dbc05c0f8f8283f1740ef6ca835ed1;p=koperkapel.git

diff --git a/koperkapel/scenes/base.py b/koperkapel/scenes/base.py
index 859f816..aa30be4 100644
--- a/koperkapel/scenes/base.py
+++ b/koperkapel/scenes/base.py
@@ -1,44 +1,152 @@
 """ Scene utilities. """
 
+import functools
+
+
+def apply_events(f):
+    """ Decorator that applies events to an engine. """
+    @functools.wraps(f)
+    def wrap(self, *args, **kw):
+        events = f(self, *args, **kw)
+        self._apply_events(events)
+    return wrap
+
 
 class Engine:
-    """ A holder for game state. """
+    """ A holder for game state & scene management.
+        """
 
-    def __init__(self, app, scene):
+    def __init__(self, app, scene, world):
         self._app = app
         self._scene = scene
+        self._world = world
+        self._viewport = (0, 0)
+
+    def _apply_events(self, events):
+        if not events:
+            return
+        for ev in events:
+            ev.apply(self)
+
+    def change_scene(self, scene):
+        self._apply_events(self._scene.exit(self._world))
+        self._scene = scene
+        self._apply_events(self._scene.enter(self._world))
+
+    def change_world(self, *args, **kw):
+        self._world.apply_event(*args, **kw)
+
+    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):
-        self._scene.update(dt)
+        return self._scene.update(self._world, 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):
-        self._scene.on_mouse_down(pos, button)
+        return self._scene.on_mouse_down(pos, button)
 
+    @apply_events
     def on_mouse_up(self, pos, button):
-        self._scene.on_mouse_up(pos, button)
+        return self._scene.on_mouse_up(pos, button)
 
+    @apply_events
     def on_key_down(self, key, mod, unicode):
-        self._scene.on_key_down(key, mod, unicode)
+        return self._scene.on_key_down(key, mod, unicode)
 
+    @apply_events
     def on_key_up(self, key, mod):
-        self._scene.on_key_up(key, mod)
+        return self._scene.on_key_up(key, mod)
 
+    @apply_events
     def on_music_end(self):
-        self._scene.on_music_end()
+        return self._scene.on_music_end()
+
+
+class Event:
+    """ Base class for events. """
+
+    ENGINE_METHOD = "unknown_event"
+
+    def __init__(self, *args, **kw):
+        self._args = args
+        self._kw = kw
+
+    def apply(self, engine):
+        getattr(engine, self.ENGINE_METHOD)(*self._args, **self._kw)
+
+
+class ChangeSceneEvent(Event):
+    """ Change to a new scene. """
+
+    ENGINE_METHOD = "change_scene"
+
+
+class WorldEvent(Event):
+    """ Be a hero. Change the world. """
+
+    ENGINE_METHOD = "change_world"
+
+
+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 update(self, dt):
+    def __init__(self):
+        self.actors = Actors()
+
+    def enter(self, world):
         pass
 
-    def draw(self, screen):
+    def exit(self, world):
+        pass
+
+    def update(self, world, dt):
         pass
 
+    def draw(self, screen, viewport):
+        screen.clear()
+        self.actors.draw(screen)
+
     def on_mouse_down(self, pos, button):
         pass