Function test_render

tests/test_vec_envs.py:592–657

(vec_env_class)

@pytest.mark.parametrize("vec_env_class", VEC_ENV_CLASSES)
def test_render(vec_env_class):
    # Skip if no X-Server
    if not os.environ.get("DISPLAY"):
        pytest.skip("No X-Server")

    env_id = "Pendulum-v1"
    # DummyVecEnv human render is currently
    # buggy because of gym:
    # https://github.com/carlosluis/stable-baselines3/pull/3#issuecomment-1356863808
    n_envs = 2
    # Human render
    vec_env = make_vec_env(
        env_id,
        n_envs,
        vec_env_cls=vec_env_class,
        env_kwargs=dict(render_mode="human"),
    )

    vec_env.reset()
    vec_env.render()

    with pytest.warns(UserWarning):
        vec_env.render("rgb_array")

    with pytest.warns(UserWarning):
        vec_env.render(mode="blah")

    for _ in range(10):
        vec_env.step([vec_env.action_space.sample() for _ in range(n_envs)])
        vec_env.render()

    vec_env.close()
    # rgb_array render, which allows human_render
    # thanks to OpenCV
    vec_env = make_vec_env(
        env_id,
        n_envs,
        vec_env_cls=vec_env_class,
        env_kwargs=dict(render_mode="rgb_array"),
    )

    vec_env.reset()
    with warnings.catch_warnings(record=True) as record:
        vec_env.render()
        vec_env.render("rgb_array")
        vec_env.render(mode="human")

    # No warnings for using human mode
    assert len(record) == 0

    with pytest.warns(UserWarning):
        vec_env.render(mode="blah")

    for _ in range(10):
        vec_env.step([vec_env.action_space.sample() for _ in range(n_envs)])
        vec_env.render()

    # Check that it still works with vec env wrapper