Passing Python Kwargs to Godot Envrionment

docs/CUSTOM_ENV.md

@@ -196,6 +196,49 @@ https://user-images.githubusercontent.com/7275864/209363084-f91b2fcb-2042-494c-9
 
 https://user-images.githubusercontent.com/7275864/209363098-a6bee0a6-dc85-4b8d-b69a-d747bcf39635.mp4
 
+### Custom environments and additional arguments:
+
+> OBSERVATION 
+> 
+> The following example focuses on how to change the **starting_level** using additional command line arguments. \
+> You can also use command line arguments to: 
+> * change the **game_difficulty**  
+> * change the **starting_character** 
+> * load a custom **game_state**
+> * update any other variable before the game starts 
+
+Let's say you have a Godot Environment with multiple levels and want to set the **starting_level** before the simulation starts. All you need to do is to pass **starting_level** as an argument, when instantiating a `StableBaselinesGodotEnv` along with the value you want to pass to Godot and you're good to go. Here's an example in python:
+
+```python
+from godot_rl.wrappers.stable_baselines_wrapper import StableBaselinesGodotEnv
+
+# we set the starting_level as RainbowRoad
+env = StableBaselinesGodotEnv(
+        env_path=PATH_TO_ENVIRONMENT,
+        port=11008,
+        env_seed=42,
+        speedup=1,
+        starting_level="RainbowRoad"
+)
+```
+After running the script you'll see in the console something like:
+```bask
+getting command line arguments
+--port=11008
+--env_seed=42
+--speedup=1
+--starting_level=RainbowRoad
+```
+Which means that those variables got to the Godot Environment successfully. However, your environment needs to support handling those environments, prior to it being built. 
+
+You can access the environment variables though the **godot_rl_agents_plugin/sync.gd** script. You'll see there's a `args` variable that stores all the command line arguments your environment received from the python script. You can access **starting_level** by doing:
+```godot
+func get_starting_level():
+    return agrs.get("starting_level", None)
+```
+
+Then, you can use the returned value to set the starting level before the game begins.
+
 ## There’s more!
 
 We have only scratched the surface of what can be achieved with Godot RL Agents, the library includes custom sensors and cameras to enrich the information available to the agent. Take a look at the [examples](https://github.com/edbeeching/godot_rl_agents_examples) to find out more!

godot_rl/core/godot_env.py

@@ -31,6 +31,7 @@ def __init__(
         action_repeat: Optional[int] = None,
         speedup: Optional[int] = None,
         convert_action_space: bool = False,
+        **kwargs,
     ):
         """
         Initialize a new instance of GodotEnv
@@ -51,7 +52,16 @@ def __init__(
             env_path = self._set_platform_suffix(env_path)
 
             self.check_platform(env_path)
-            self._launch_env(env_path, port, show_window, framerate, seed, action_repeat, speedup)
+            self._launch_env(
+                env_path,
+                port,
+                show_window,
+                framerate,
+                seed,
+                action_repeat,
+                speedup,
+                **kwargs,
+            )
         else:
             print("No game binary has been provided, please press PLAY in the Godot editor")
 
@@ -277,7 +287,17 @@ def _close(self):
         print("exit was not clean, using atexit to close env")
         self.close()
 
-    def _launch_env(self, env_path, port, show_window, framerate, seed, action_repeat, speedup):
+    def _launch_env(
+        self,
+        env_path,
+        port,
+        show_window,
+        framerate,
+        seed,
+        action_repeat,
+        speedup,
+        **kwargs,
+    ):
         # --fixed-fps {framerate}
         path = convert_macos_path(env_path) if platform == "darwin" else env_path
 
@@ -291,6 +311,9 @@ def _launch_env(self, env_path, port, show_window, framerate, seed, action_repea
             launch_cmd += f" --action_repeat={action_repeat}"
         if speedup is not None:
             launch_cmd += f" --speedup={speedup}"
+        if len(kwargs) > 0:
+            for key, value in kwargs.items():
+                launch_cmd += f" --{key}={value}"
 
         launch_cmd = launch_cmd.split(" ")
         self.proc = subprocess.Popen(

godot_rl/wrappers/petting_zoo_wrapper.py

@@ -26,7 +26,7 @@ def env(render_mode=None):
 class GDRLPettingZooEnv(ParallelEnv):
     metadata = {"render_modes": ["human"], "name": "GDRLPettingZooEnv"}
 
-    def __init__(self, port=GodotEnv.DEFAULT_PORT, show_window=True, seed=0, config: Dict = {}):
+    def __init__(self, port=GodotEnv.DEFAULT_PORT, show_window=True, seed=0, config: Dict = None):
         """
         The init method takes in environment arguments and should define the following attributes:
         - possible_agents
@@ -38,15 +38,23 @@ def __init__(self, port=GodotEnv.DEFAULT_PORT, show_window=True, seed=0, config:
 
         These attributes should not be changed after initialization.
         """
+        config = config or {}  # initialize config as empty dict if None
+        extra_arguments = {
+            key: value
+            for key, value in config.items()
+            if key not in ["env_path", "show_window", "action_repeat", "speedup", "seed", "port"]
+        }
+
         # Initialize the Godot Env which we will wrap
         self.godot_env = GodotEnv(
-            env_path=config.get("env_path"),
-            show_window=config.get("show_window"),
-            action_repeat=config.get("action_repeat"),
-            speedup=config.get("speedup"),
+            env_path=config["env_path"],
+            show_window=show_window,
+            action_repeat=config["action_repeat"],
+            speedup=config["speedup"],
             convert_action_space=False,
             seed=seed,
             port=port,
+            **extra_arguments,
         )
 
         self.render_mode = None  # Controlled by the env
@@ -125,7 +133,7 @@ def step(self, actions):
         # Godot env have done = true. For agents that received no actions, we will set zeros instead for
         # compatibility.
         godot_actions = [
-            actions[agent] if agent in actions else np.zeros_like(self.action_spaces[agent_idx].sample())
+            (actions[agent] if agent in actions else np.zeros_like(self.action_spaces[agent_idx].sample()))
             for agent_idx, agent in enumerate(self.agents)
         ]
 

godot_rl/wrappers/ray_wrapper.py

@@ -13,19 +13,22 @@
 
 
 class RayVectorGodotEnv(VectorEnv):
-    def __init__(
-        self,
-        port=10008,
-        seed=0,
-        config=None,
-    ) -> None:
+    def __init__(self, port=10008, seed=0, config=None) -> None:
+        config = config or {}  # initialize config as empty dict if None
+        extra_arguments = {
+            key: value
+            for key, value in config.items()
+            if key not in ["env_path", "show_window", "action_repeat", "speedup", "seed", "port"]
+        }
+
         self._env = GodotEnv(
             env_path=config["env_path"],
             port=port,
             seed=seed,
             show_window=config["show_window"],
             action_repeat=config["action_repeat"],
             speedup=config["speedup"],
+            **extra_arguments,
         )
         super().__init__(
             observation_space=self._env.observation_space,