Sprite源代码

class Sprite(object):
    def __init__(self, *groups):
        self.__g = {} # The groups the sprite is in
        if groups:
            self.add(*groups)

    def add(self, *groups):
        has = self.__g.__contains__
        for group in groups:
            if hasattr(group, '_spritegroup'):
                if not has(group):
                    group.add_internal(self)
                    self.add_internal(group)
            else:
                self.add(*group)

    def remove(self, *groups):
        has = self.__g.__contains__
        for group in groups:
            if hasattr(group, '_spritegroup'):
                if has(group):
                    group.remove_internal(self)
                    self.remove_internal(group)
            else:
                self.remove(*group)

    def add_internal(self, group):
        self.__g[group] = 0

    def remove_internal(self, group):
        del self.__g[group]

    def update(self, *args):
        pass

    def kill(self):
        for c in self.__g:
            c.remove_internal(self)
        self.__g.clear()

    def groups(self):
        return list(self.__g)

    def alive(self):
        return truth(self.__g)

    def __repr__(self):
        return "<%s sprite(in %d groups)>" % (self.__class__.__name__, len(self.__g))