tabakrolletjie/engine.py

   1 """ Engine for moving controll scenes and tranistions between them.
   2 """
   3
   4 import pygame.display
   5 import pygame.event
   6 import pygame.time
   7
   8 import pygame.locals as pgl
   9
  10 from .constants import FPS
  11 from .events import QuitEvent, SceneChangeEvent
  12
  13
  14 class Engine(object):
  15     def __init__(self, screen, gamestate):
  16         self._screen = screen
  17         self._gamestate = gamestate
  18         self._scene = None
  19
  20     def set_scene(self, scene):
  21         if self._scene is not None:
  22             self._scene.exit(self._gamestate)
  23         self._scene = scene
  24         if scene is not None:
  25             self._scene.enter(self._gamestate)
  26
  27     def run(self):
  28         clock = pygame.time.Clock()
  29
  30         while True:
  31             events = pygame.event.get()
  32             for ev in events:
  33                 if QuitEvent.matches(ev) or ev.type == pgl.QUIT:
  34                     self.set_scene(None)
  35                     return
  36                 elif SceneChangeEvent.matches(ev):
  37                     self.set_scene(ev.scene)
  38                 else:
  39                     self._scene.event(ev, self._gamestate)
  40
  41             self._scene.render(self._screen, self._gamestate)
  42             pygame.display.flip()
  43             clock.tick(FPS)