1 """ Scene utilities. """
7 """ Decorator that applies events to an engine. """
9 def wrap(self, *args, **kw):
10 events = f(self, *args, **kw)
11 self._apply_events(events)
16 """ A holder for game state & scene management.
19 def __init__(self, app, scene, world):
23 self._update_vehicle = False
25 def _apply_events(self, events):
31 def change_scene(self, scene):
32 self._apply_events(self._scene.exit(self._world.proxy()))
34 self._apply_events(self._scene.enter(self._world.proxy()))
36 def change_world(self, *args, **kw):
37 self._world.apply_event(*args, **kw)
40 from pgzero.game import exit
43 def move_screen(self, offset):
44 self._scene.move_screen(offset)
47 self._world.add_new_roach()
51 return self._scene.update(self._world.proxy(), self, dt)
54 self._scene.draw(self._app.screen)
57 def on_mouse_down(self, pos, button):
58 return self._scene.on_mouse_down(pos, button)
61 def on_mouse_up(self, pos, button):
62 return self._scene.on_mouse_up(pos, button)
65 def on_key_down(self, key, mod, unicode):
66 return self._scene.on_key_down(key, mod, unicode)
69 def on_key_up(self, key, mod):
70 return self._scene.on_key_up(key, mod)
73 def on_music_end(self):
74 return self._scene.on_music_end()
78 """ Base class for events. """
80 ENGINE_METHOD = "unknown_event"
82 def __init__(self, *args, **kw):
86 def apply(self, engine):
87 getattr(engine, self.ENGINE_METHOD)(*self._args, **self._kw)
90 class ChangeSceneEvent(Event):
91 """ Change to a new scene. """
93 ENGINE_METHOD = "change_scene"
96 class WorldEvent(Event):
97 """ Be a hero. Change the world. """
99 ENGINE_METHOD = "change_world"
102 class QuitEvent(Event):
103 """ Quit the game. """
105 ENGINE_METHOD = "quit_game"
108 class MoveViewportEvent(Event):
109 """ Change to a new scene. """
111 ENGINE_METHOD = "move_screen"
113 class AddRoachEvent(Event):
114 """ Change to a new scene. """
116 ENGINE_METHOD = "add_roach"
120 """ A single layer of actors. """
122 def __init__(self, name):
127 return iter(self.actors)
129 def __getitem__(self, i):
130 return self.actors[i]
133 return len(self.actors)
135 def add(self, actor):
136 self.actors.append(actor)
142 def remove(self, actor):
143 self.actors.remove(actor)
148 """ Layers of actors.
150 Actors may be rendered in different layers. Layers with lower levels
151 are rendered lower than layers with higher ones.
155 self._ordered_layers = []
157 self.add_layer("default", 0)
159 def __getattr__(self, name):
160 return self._layers[name]
162 def add_layer(self, name, level):
163 layer = self._layers[name] = Layer(name)
164 self._ordered_layers.append((level, name))
165 self._ordered_layers.sort()
168 def add(self, actor, layer="default"):
169 return self._layers[layer].add(actor)
171 def remove(self, actor, layer="default"):
172 return self._layers[layer].remove(actor)
174 def draw(self, screen):
175 for lvl, name in self._ordered_layers:
176 for actor in self._layers[name]:
177 # actor.draw doesn't allow blitting to anything other than
179 screen.blit(actor._surf, actor.topleft)
182 def defer_to_update(f):
183 """ Defers a function until the next update run. """
185 def wrapper(self, *args, **kw):
186 self._deferred_updates.append((f, args, kw))
191 """ Base class for scenes. """
194 self.actors = Actors()
195 self.viewport = (0, 0)
196 self._deferred_updates = []
198 def move_screen(self, offset):
199 self.viewport = (self.viewport[0] + offset[0],
200 self.viewport[1] + offset[1])
202 def calc_offset(self, x, y):
203 """ Return a position offset by the viewport. """
204 return x - self.viewport[0], y - self.viewport[1]
206 def enter(self, world):
209 def exit(self, world):
212 def update(self, world, engine, dt):
213 deferred_updates, self._deferred_updates = self._deferred_updates, []
214 for f, args, kw in deferred_updates:
215 f(self, world, *args, **kw)
217 def draw(self, screen):
219 self.actors.draw(screen)
221 def on_mouse_down(self, pos, button):
224 def on_mouse_up(self, pos, button):
227 def on_key_down(self, key, mod, unicode):
230 def on_key_up(self, key, mod):
233 def on_music_end(self):