Some minor changes

[Jialn]

Some minor changes like using action_space.sample() instead of np.random(action.shape), use np.clip instead of min(max()), etc.

[Jialn]

Also added rendering mode "rgb_array". Since gzclient might not be always opening, and we can not directly access user camera of gzclient in gzserver, this mode is done by inserting a camera to the world.

The default view pose is like below. User can set view point by setting pose of "self._rendering_camera" in "env.step()" .

[emailweixu]

Does alf.trainer.on_policy_trainer.play() generate right video from this?

[emailweixu]

It seems that you need to add metadata like this so the video can be captured: https://github.com/bulletphysics/bullet3/blob/0aaae872451a69d0c93b0c8ed818667de4ad5653/examples/pybullet/gym/pybullet_envs/env_bases.py#L16

[Jialn]

It seems that you need to add metadata like this so the video can be captured: https://github.com/bulletphysics/bullet3/blob/0aaae872451a69d0c93b0c8ed818667de4ad5653/examples/pybullet/gym/pybullet_envs/env_bases.py#L16

OK， I'll add it.

[Jialn]

Because the rendered image has no grid, and the yellow texture in texture_ground_plane draws too much attention, I changed the yellow texture to grey texture with 1m x 1m grid:

[Jialn]

the default view point, this also suits for icubwalk: PR2 has been set to a closer camera pos simple navi:

[emailweixu]

Do the model trained with the previous ground plane texture work with the new ground texture?

[emailweixu]

And since the ground texture is changed. Perhaps we should update the videos in README.md