in gym/envs/box2d/car_racing.py [0:0]
def _render(self, mode: str):
assert mode in self.metadata["render_modes"]
pygame.font.init()
if self.screen is None and mode == "human":
pygame.init()
pygame.display.init()
self.screen = pygame.display.set_mode((WINDOW_W, WINDOW_H))
if self.clock is None:
self.clock = pygame.time.Clock()
if "t" not in self.__dict__:
return # reset() not called yet
self.surf = pygame.Surface((WINDOW_W, WINDOW_H))
assert self.car is not None
# computing transformations
angle = -self.car.hull.angle
# Animating first second zoom.
zoom = 0.1 * SCALE * max(1 - self.t, 0) + ZOOM * SCALE * min(self.t, 1)
scroll_x = -(self.car.hull.position[0]) * zoom
scroll_y = -(self.car.hull.position[1]) * zoom
trans = pygame.math.Vector2((scroll_x, scroll_y)).rotate_rad(angle)
trans = (WINDOW_W / 2 + trans[0], WINDOW_H / 4 + trans[1])
self._render_road(zoom, trans, angle)
self.car.draw(
self.surf,
zoom,
trans,
angle,
mode not in ["state_pixels_list", "state_pixels"],
)
self.surf = pygame.transform.flip(self.surf, False, True)
# showing stats
self._render_indicators(WINDOW_W, WINDOW_H)
font = pygame.font.Font(pygame.font.get_default_font(), 42)
text = font.render("%04i" % self.reward, True, (255, 255, 255), (0, 0, 0))
text_rect = text.get_rect()
text_rect.center = (60, WINDOW_H - WINDOW_H * 2.5 / 40.0)
self.surf.blit(text, text_rect)
if mode == "human":
pygame.event.pump()
self.clock.tick(self.metadata["render_fps"])
assert self.screen is not None
self.screen.fill(0)
self.screen.blit(self.surf, (0, 0))
pygame.display.flip()
if mode == "rgb_array":
return self._create_image_array(self.surf, (VIDEO_W, VIDEO_H))
elif mode == "state_pixels":
return self._create_image_array(self.surf, (STATE_W, STATE_H))
else:
return self.isopen