add brax env

problem/rl_env/brax_env.py

@@ -0,0 +1,45 @@
+from dataclasses import dataclass
+from typing import Callable
+
+import jax.numpy as jnp
+from brax import envs
+from core import State
+from .rl_jit import RLEnv, RLEnvConfig
+
+
+@dataclass(frozen=True)
+class BraxConfig(RLEnvConfig):
+    env_name: str = "ant"
+    backend: str = "generalized"
+
+    def __post_init__(self):
+        # TODO: Check if env_name is registered
+        # assert self.env_name in gymnax.registered_envs, f"Env {self.env_name} not registered"
+        pass
+
+
+class BraxEnv(RLEnv):
+    def __init__(self, config: BraxConfig = BraxConfig()):
+        super().__init__(config)
+        self.config = config
+        self.env = envs.create(env_name=config.env_name, backend=config.backend)
+
+    def env_step(self, randkey, env_state, action):
+        state = self.env.step(env_state, action)
+        return state.obs, state, state.reward, state.done.astype(jnp.bool_), state.info
+
+    def env_reset(self, randkey):
+        init_state = self.env.reset(randkey)
+        return init_state.obs, init_state
+
+    @property
+    def input_shape(self):
+        return (self.env.observation_size, )
+
+    @property
+    def output_shape(self):
+        return (self.env.action_size, )
+
+    def show(self, randkey, state: State, act_func: Callable, params):
+        # TODO
+        raise NotImplementedError("im busy! to de done!")