tabakrolletjie/obstacles.py

   1 """ Obstacles for light and space mould. """
   2
   3 import pymunk
   4 import pymunk.pygame_util
   5 import pygame.draw
   6
   7 from .constants import OBSTACLE_CATEGORY
   8
   9 OBSTACLE_FILTER = pymunk.ShapeFilter(categories=OBSTACLE_CATEGORY)
  10
  11
  12 class ObstacleManager(object):
  13     """ Manages a set of obstacles. """
  14
  15     def __init__(self, space, gamestate):
  16         self._space = space
  17         self._obstacles = [
  18             BaseObstacle.load(cfg) for cfg in gamestate.station["obstacles"]]
  19         for obs in self._obstacles:
  20             obs.add(self._space)
  21
  22     def render(self, surface):
  23         for obs in self._obstacles:
  24             obs.render(surface)
  25
  26
  27 class BaseObstacle(object):
  28     def __init__(self):
  29         self.body = pymunk.Body(0, 0, pymunk.body.Body.STATIC)
  30         self.shapes = []
  31
  32     def add(self, space):
  33         if self.body.space is not None:
  34             space.remove(self.body, *self.body.shapes)
  35         for shape in self.shapes:
  36             shape.filter = OBSTACLE_FILTER
  37         space.add(self.body, *self.shapes)
  38
  39     def render(self, surface):
  40         raise NotImplementedError("Obstacles should implement .render().")
  41
  42     @classmethod
  43     def load(cls, config):
  44         kw = config.copy()
  45         obstacle_type = kw.pop("type")
  46         [obstacle_class] = [
  47             c for c in cls.__subclasses__()
  48             if c.__name__.lower() == obstacle_type]
  49         return obstacle_class(**kw)
  50
  51
  52 class Wall(BaseObstacle):
  53
  54     def __init__(self, vertices):
  55         super(Wall, self).__init__()
  56         self.shapes.append(pymunk.Poly(self.body, vertices))
  57
  58     def render(self, surface):
  59         for shape in self.shapes:
  60             pygame_poly = [
  61                 pymunk.pygame_util.to_pygame(v, surface) for v in
  62                 shape.get_vertices()]
  63             pygame.draw.polygon(surface, (0, 0, 0), pygame_poly)