Having problems with using the self.is_ball_owned_by_enemy() function

[vivekmishra369]

Hi,

I am using rcssserver-15.3.0. I tried running a sample game using two instances of the main.py file and used the agent_2.py as all my player clients. The clients throw an error " 'NoneType' object has no attribute 'distance' " in a few cases when the self.wm.is_ball_owned_by_enemy() method is invoked from the client methods like shall_move_to_ball(). This kills the client.

I want to know if I am doing something wrong or this is a known problem.

[kengz]

hmm haven't encountered that before, but that was over a year ago. A possibility is that whatever object that was called got deleted, hence becoming a None object, and when calling that <object>.distance it blows up.

Could you paste the terminal output when it throws the errors here? would help to pin that down

[vivekmishra369]

The following error message is thrown right before the player thread dies:

Exception in thread think_loop: Traceback (most recent call last): File "/usr/lib/python2.7/threading.py", line 810, in __bootstrap_inner self.run() File "/usr/lib/python2.7/threading.py", line 763, in run self.target(*self.args, **self.kwargs) File "/home/vivek/Desktop/robocup virtual/robocup-soccer-master/aigent/soccerpy/agent.py", line 219, in think_loop self.think() File "/home/vivek/Desktop/robocup virtual/robocup-soccer-master/aigent/agent_2.py", line 88, in think return self.decisionLoop() File "/home/vivek/Desktop/robocup virtual/robocup-soccer-master/aigent/agent_2.py", line 316, in decisionLoop ball_with_enemy = self.wm.is_ball_owned_by_enemy() File "/home/vivek/Desktop/robocup virtual/robocup-soccer-master/aigent/soccerpy/world_model.py", line 660, in is_ball_owned_by_enemy if p.side != self.side and self.euclidean_distance(self.get_object_absolute_coords(self.ball), self.get_object_absolute_coords(p)) < self.server_parameters.kickable_margin: File "/home/vivek/Desktop/robocup virtual/robocup-soccer-master/aigent/soccerpy/world_model.py", line 516, in get_object_absolute_coords if obj.distance is None: AttributeError: 'NoneType' object has no attribute 'distance'

For the time being, I am circumventing this problem by catching this error, I modified the method to the following:

` def is_ball_owned_by_enemy(self):

#Returns if the ball is in possession by the enemy team.

for p in self.players:

    # skip enemy and unknwon players

    try:

        if p.side != self.side and self.euclidean_distance(self.get_object_absolute_coords(self.ball), self.get_object_absolute_coords(p)) < self.server_parameters.kickable_margin:

            return True

    except Exception as e:

        print 'error in ball owned by enemy function : ',e

        continue

    else:
        continue

return False`

Thanks in advance.

[kengz]

ok u could change https://github.com/kengz/robocup-soccer/blob/master/aigent/soccerpy/world_model.py#L514 by replacing with

        # we can't calculate this without a distance to the object
        if obj is None or obj.distance is None:
            return None

[vivekmishra369]

Thanks