PyBullet RL Environment Rendering not consistently implemented

[avandekleut]

Some environments under pybullet_envs/bullet/ such as kukaCamGymEnv.py and raceCarGymEnv.py are missing declarations for self._cam_dist and other variables needed to call render(mode='rgb_array). In some cases, such as in cartpole_bullet.py this variable is declared locally inside of the render method. For other environments, they subclass MJCFBaseBulletEnv from pybullet_envs/env_bases.py which declares self._cam_dist and other variables as instance variables of the class.

[erwincoumans]

Thanks for the report. There is no activate development on those envs (lack of resources). If you care, you can create a small pull request.