Rendering of CartPoleVectorEnv is broken

[TimSchneider42]

Describe the bug

Hi,

the rendering of CartPoleVectorEnv is broken in two places:

1. In line 548, self.clock is assigned instead of self.clocks
2. In line 561, self.state is used instead of state

Because of these two bugs, CartPoleVectorEnv.render() throws exceptions. I will create a PR in a moment.

Best,
Tim

Code example

No response

System info

No response

Additional context

No response

Checklist

• I have checked that there is no similar issue in the repo

[TimSchneider42]

Just noticed that I overlooked #872, which addresses this issue already but still needs a pull request. Apologies for the duplication! Should I close this issue in favor of #872?

[pseudo-rnd-thoughts]

Thanks, for the issue. My proposal was to actually not contain "human" rendering in the custom vector environment as this is difficult to maintain.
Rather, we should have a wrappers.vector.HumanRendering for which all "human" vector rendering is computed through.
This still requires rgb array rendering in the vector environment but this feels like a simpler solution for most vector environments.

Thoughts @TimSchneider42 and maybe @Kallinteris-Andreas or @RedTachyon

[TimSchneider42]

I like the idea of solving human rendering with a wrapper. At least in this case, I expect it to be easier to implement and maintain, since the rgb_array image simply gets rendered by pygame.

[pseudo-rnd-thoughts]

Agreed. I have been thinking about how to implement the vector human rendering but I haven't come to a satisfactory general solution.
If you have any idea, I would love to hear them

[TimSchneider42]

I think for most environments we could simply render in "rgb_array" mode and then have the wrapper you proposed render all of them side by side in a single window with pygame. For more sophisticated environments, like this one, though, there should still be an option for custom rendering solutions, like just showing the simulator interface without having to render RGB images.

In general, I think that human rendering should be detached from RGB rendering in the API. I just wrote a small proposal about that in #1010.

[RogerJL]

Can this be closed now?

[TimSchneider42]

Yes, it is fixed