Failed to visualize cartpole in tutorial.py when setting gui: True

[swuuu]

Hi,

I'm trying to run the tutorial.py (i.e., python3 tutorial.py --algo ppo --task cartpole --overrides ./tutorial_configs/tutorial_ppo_cartpole.yaml --output_dir ./tutorial_models --tag tutorial_results/ppo --thread 1 --seed 22) with the GUI on. To enable the GUI, I have added gui: True under the task_config field in the tutorial_ppo_cartpole.yaml file. However, this is the error that I get:

I also didn't change the cartpole.py file and my PyBullet version is the same as the one in the requirements.txt.

Any help would be appreciated.

Thanks,
Stanley

[adamhall]

Hi @swuuu,

Thanks for the comment. I've seen this error before in other contexts and I'll see if I can reproduce it. It usually has to do with the fact that pybullet only allows one gui open at a time, so I suspect an environment is either not being closed properly, or multiple are being opened at once. Would you be able to reply with the OS you are using, and the conda and pip packages+versions you are using pip3 list or conda list , along with the full output?

Thanks :)

[swuuu]

Hi @adamhall,

Thanks for your help!
I'm using Ubuntu 20.04.4.
My packages are:

The full output is:

(safe) stanleyzqwu@Stanley-Ubuntu:~/Documents/McGill/COMP579/final-project/safe-control-gym/walkthroughs$ python3 tutorial.py --algo ppo --task cartpole --overrides ./tutorial_configs/tutorial_ppo_cartpole.yaml --output_dir ./tutorial_models --tag tutorial_results/ppo --thread 1 --seed 222
pybullet build time: Oct 11 2021 20:59:39
/home/stanleyzqwu/miniconda3/envs/safe/lib/python3.8/site-packages/gym/spaces/box.py:73: UserWarning: WARN: Box bound precision lowered by casting to float32
  logger.warn(
startThreads creating 1 threads.
starting thread 0
started thread 0 
argc=2
argv[0] = --unused
argv[1] = --start_demo_name=Physics Server
ExampleBrowserThreadFunc started
X11 functions dynamically loaded using dlopen/dlsym OK!
X11 functions dynamically loaded using dlopen/dlsym OK!
Creating context
Created GL 3.3 context
Direct GLX rendering context obtained
Making context current
GL_VENDOR=AMD
GL_RENDERER=Radeon RX 580 Series (POLARIS10, DRM 3.42.0, 5.15.0-69-generic, LLVM 12.0.0)
GL_VERSION=4.6 (Core Profile) Mesa 21.2.6
GL_SHADING_LANGUAGE_VERSION=4.60
pthread_getconcurrency()=0
Version = 4.6 (Core Profile) Mesa 21.2.6
Vendor = AMD
Renderer = Radeon RX 580 Series (POLARIS10, DRM 3.42.0, 5.15.0-69-generic, LLVM 12.0.0)
b3Printf: Selected demo: Physics Server
startThreads creating 1 threads.
starting thread 0
started thread 0 
MotionThreadFunc thread started
ven = AMD
@1=vertcat(x, x_dot, theta, theta_dot), (mac(mac((0.5*(@1-Xr)'),Q,zeros(1x4)),(@1-Xr),0)+(((0.5*(U-Ur))*R)*(U-Ur)))
ven = AMD
Traceback (most recent call last):
  File "tutorial.py", line 153, in <module>
    func(config)
  File "tutorial.py", line 35, in train
    control_agent = make(config.algo,
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 149, in make
    return registry.make(id, *args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 102, in make
    obj = spec.make(*args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 79, in make
    obj = cls(*args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/controllers/ppo/ppo.py", line 48, in __init__
    self.env = make_vec_envs(env_func, None, self.rollout_batch_size, self.num_workers, seed)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/envs/env_wrappers/vectorized_env/__init__.py", line 65, in make_vec_envs
    return DummyVecEnv(env_fns)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/envs/env_wrappers/vectorized_env/dummy_vec_env.py", line 20, in __init__
    self.envs = [fn() for fn in env_fns]
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/envs/env_wrappers/vectorized_env/dummy_vec_env.py", line 20, in <listcomp>
    self.envs = [fn() for fn in env_fns]
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/envs/env_wrappers/vectorized_env/__init__.py", line 33, in _thunk
    env = env_func(seed=e_seed, **env_config)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 149, in make
    return registry.make(id, *args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 102, in make
    obj = spec.make(*args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/utils/registration.py", line 79, in make
    obj = cls(*args, **kwargs)
  File "/home/stanleyzqwu/Documents/McGill/COMP579/final-project/safe-control-gym/safe_control_gym/envs/gym_control/cartpole.py", line 164, in __init__
    self.PYB_CLIENT = p.connect(p.GUI)
pybullet.error: Only one local in-process GUI/GUI_SERVER connection allowed. Use DIRECT connection mode or start a separate GUI physics server (ExampleBrowser, App_SharedMemoryPhysics_GUI, App_SharedMemoryPhysics_VR) and connect over SHARED_MEMORY, UDP or TCP instead.
numActiveThreads = 0
stopping threads
Thread with taskId 0 exiting
Thread TERMINATED
destroy semaphore
semaphore destroyed
destroy main semaphore
main semaphore destroyed
finished
numActiveThreads = 0
btShutDownExampleBrowser stopping threads
Thread with taskId 0 exiting
Thread TERMINATED
destroy semaphore
semaphore destroyed
destroy main semaphore
main semaphore destroyed