Updates documentation with instructions for H1 demo (#330)

# Description

Adds instructions for manipulating H1 humanoid demo and fixes some
documentation issues in changelog.

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## Type of change

- This change requires a documentation update

## Screenshots

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## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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docs/source/overview/showroom.rst

@@ -191,3 +191,19 @@ A few quick showroom scripts to run and checkout:
    .. image:: ../_static/demos/h1_locomotion.jpg
       :width: 100%
       :alt: H1 locomotion in Isaac Lab
+
+   This is an interactive demo that can be run using the mouse and keyboard.
+   To enter third-person perspective, click on a humanoid character in the scene.
+   Once entered into third-person view, the humanoid can be controlled by keyboard using:
+
+   * ``UP``: go forward
+   * ``LEFT``: turn left
+   * ``RIGHT``: turn right
+   * ``DOWN``: stop
+   * ``C``: switch between third-person and perspective views
+   * ``ESC``: exit current third-person view
+
+   If a misclick happens outside of the humanoid bodies when selecting a humanoid,
+   a message is printed to console indicating the error, such as
+   ``The selected prim was not a H1 robot`` or
+   ``Multiple prims are selected. Please only select one!``.

scripts/demos/h1_locomotion.py

@@ -86,6 +86,7 @@ class H1RoughDemo:
         # create envionrment
         env_cfg = H1RoughEnvCfg_PLAY()
         env_cfg.scene.num_envs = 25
+        env_cfg.episode_length_s = 1000000
         env_cfg.curriculum = None
         env_cfg.commands.base_velocity.ranges.lin_vel_x = (0.0, 1.0)
         env_cfg.commands.base_velocity.ranges.heading = (-1.0, 1.0)

source/isaaclab/docs/CHANGELOG.rst

@@ -341,8 +341,8 @@ Added
 ~~~~~~~~~~~~~~~~~~~~
 
 Added
-
 ^^^^^
+
 * Refactored retargeting code from Se3Handtracking class into separate modules for better modularity
 * Added scaffolding for developing additional retargeters (e.g. dex)