def init(screen_size):
screen = init_screen(screen_size)
images = {}
images['star0'] = pygame.image.load('img/star0.png')
images['star0'].set_colorkey((0, 0, 0))
images['star1'] = pygame.image.load('img/star0.png')
images['star1'].set_colorkey((0, 0, 0))
images['star0yellow'] = colored_copy(images['star0'], (0, 255, 255, 0))
sim = Simulation()
sim.draw_stars(images, screen)
return screen, images, sim
