Add close. Fix rendering to conform with gym

fancy_gym/envs/mujoco/air_hockey/air_hockey_env_wrapper.py

@@ -7,8 +7,6 @@ from fancy_gym.envs.mujoco.air_hockey import position_control_wrapper as positio
 from fancy_gym.envs.mujoco.air_hockey.utils import robot_to_world
 from mushroom_rl.core import Environment
 
-MAX_EPISODE_STEPS_AIRHOCKEY = 45000 # For a tournament env, the game can last up to 15 minutes
-
 class AirHockeyEnv(Environment):
     metadata = {"render_modes": ["human"], "render_fps": 60}
 
@@ -84,6 +82,8 @@ class AirHockeyEnv(Environment):
         self.env_info['env_name'] = self.env_name
 
         self.render_mode = render_mode
+        self.render_human_active = False
+
         super().__init__(self.base_env.info)
 
     def step(self, action):
@@ -111,10 +111,14 @@ class AirHockeyEnv(Environment):
 
         if self.env_info['env_name'] == "tournament":
             obs = np.array(np.split(obs, 2))
+        
+        if self.render_human_active:
+            self.base_env.render()
+
         return obs, reward, done, False, info
 
     def render(self):
-        self.base_env.render()
+        self.render_human_active = True
 
     def reset(self, seed=None, options={}):
         self.base_env.seed(seed)
@@ -146,6 +150,9 @@ class AirHockeyEnv(Environment):
     @property
     def unwrapped(self):
         return self
+    
+    def close(self):
+        return
 
 
 if __name__ == "__main__":