add docs for dynamics, rendering, custom example

docs/src/usage/customized_usage.rst

@@ -7,10 +7,6 @@ For a basic usage example, see :ref:`basic_usage`.
 
 The environment also provides options for customization.
 
-Custom Map
-------------
-Work in progress on how to add a custom map.
-
 Random Track Generator
 -----------------------
 
@@ -35,6 +31,10 @@ For example, to generate 3 random maps and store them in the directory `custom_m
 	python examples/random_trackgen.py --seed 42 --n-maps 3 --outdir custom_maps
 
 
-.. image:: ../../../../src/assets/random_trackgen.png
+.. image:: /assets/random_trackgen.png
 	:width: 800
-	:align: center
+	:align: center
+
+Custom Map
+------------
+Work in progress on how to add a custom map.

docs/src/usage/dynamics.rst

@@ -1,6 +1,50 @@
-_dynamics:
+.. _dynamics:
 
-Dynamics
+Vehicle Dynamics
 =====================
 
-Work in progress.
+The vehicle dynamics are modeled using a single-track model, as in [AlKM17]_.
+
+We support two vehicle dynamics models:
+- Kinematic Single-Track Model (`ks`): Simpler model that considers only the kinematics of the vehicle, i.e., the position, orientation, and velocity, ignoring the forces that act on the vehicle.
+- Single-Track Model (`st`): More complex model that considers the forces that act on the vehicle, such as the tire forces.
+
+Despite the fact that the single-track model is a simplified model, it is able to capture the
+tire slip effects on the slip angle, which is important for accurate simulation at the physical
+limits of the vehicle.
+
+
+Dynamics Configuration
+----------------------
+The environment comes with a *default* dynamics model, which can be changed using the environment configuration.
+
+The dynamics model can be configured at the environment creation:
+
+.. code:: python
+
+    import gymnasium as gym
+
+    env = gym.make(
+		"f110_gym:f110-v0",
+		config={
+			"model": "ks"
+		})
+    obs, infos = env.reset()
+
+or after the environment creation:
+
+.. code:: python
+
+    import gymnasium as gym
+
+    env = gym.make("f110_gym:f110-v0")
+    env.configure({
+        "model": "ks",
+    })
+    obs, infos = env.reset()
+
+
+
+.. rubric:: References
+
+.. [AlKM17] Althoff, M.; Koschi, M.; Manzinger, S..: CommonRoad: Composable benchmarks for motion planning on roads. In: 2017 IEEE Intelligent Vehicles Symposium (IV). IEEE, 2017.

docs/src/usage/rendering.rst

@@ -3,4 +3,66 @@
 Rendering
 =====================
 
-Work in progress.
+The environment rendering is done with `pygame`.
+
+As by default in gymnasium environments,
+there are multiple rendering modes available:
+
+- `human`: for real-time rendering with `pygame`;
+
+- `rgb_array`: for collecting the current frame as a numpy array;
+
+- `rgb_array_list`: for collecting multiple frames into a list. This is useful to generate smooth videos when using frame-skipping.
+
+Additionally, for fast rendering and debugging, we add:
+
+- `human-fast`: faster-than-real-time rendering. Up to 10x faster based on the host machine.
+
+Rendering Configuration
+------------------------
+
+The user can customize the rendering mode with the `rendering_mode` parameter in the environment configuration.
+
+.. code:: python
+
+    import gymnasium as gym
+
+    env = gym.make(
+        "f110_gym:f110-v0",
+        render_mode="human-fast",
+    )
+    obs, infos = env.reset()
+    done = False
+
+    while not done:
+        action = env.action_space.sample()
+        obs, reward, done, infos = env.step(action)
+        env.render()
+
+
+.. note::
+    When rendering in `human` mode,
+    the user can interact to change the agent to focus on by pressing the left/right/middle mouse button,
+    as described by the instructions diplayed in the top of the window.
+
+Parameter Configuration
+-----------------------
+
+The user can customize the rendering parameters in the `f1tenth_gym.rendering/rendering.yaml` file:
+
+- `window_size`: width and height of the window in pixels
+
+- `focus_on`: agent id to focus on (e.g., `agent_0`) or `null` for map view
+
+- `zoom_in_factor`: zoom in factor. 1.0 is no zoom, >1.0 is zoom in, <1.0 is zoom out
+
+- `show_wheels`: it toggles the visualization of the vehicle wheels
+
+- `car_tickness`: thickness of the car border
+
+- `show_info`: it toggles the visualization of the instruction text
+
+- `vehicle_palette`: cyclic list of colors for the vehicles (e.g., first agent takes the first color, second agent takes the second color, etc. and then it starts again from the first color)
+
+
+