From c90f94780253c70ec89ce1f7695dabf7017b7b14 Mon Sep 17 00:00:00 2001
From: Umut Ucak <umutucak@proton.me>
Date: Thu, 5 Oct 2023 17:09:10 +0200
Subject: [PATCH] Multiwalker dead variable removal + macOS pygame fix (#1107)

---
 pettingzoo/classic/connect_four/connect_four.py | 1 +
 pettingzoo/sisl/multiwalker/multiwalker.py      | 6 ++++--
 pettingzoo/sisl/multiwalker/multiwalker_base.py | 9 +++------
 pettingzoo/sisl/pursuit/pursuit_base.py         | 3 ++-
 pettingzoo/sisl/waterworld/waterworld_base.py   | 3 ++-
 5 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/pettingzoo/classic/connect_four/connect_four.py b/pettingzoo/classic/connect_four/connect_four.py
index 5aa637930..e2a2390e9 100644
--- a/pettingzoo/classic/connect_four/connect_four.py
+++ b/pettingzoo/classic/connect_four/connect_four.py
@@ -283,6 +283,7 @@ def render(self):
                 )
 
         if self.render_mode == "human":
+            pygame.event.pump()
             pygame.display.update()
             self.clock.tick(self.metadata["render_fps"])
 
diff --git a/pettingzoo/sisl/multiwalker/multiwalker.py b/pettingzoo/sisl/multiwalker/multiwalker.py
index b398268e9..839b6152e 100644
--- a/pettingzoo/sisl/multiwalker/multiwalker.py
+++ b/pettingzoo/sisl/multiwalker/multiwalker.py
@@ -151,9 +151,11 @@ def __init__(self, *args, **kwargs):
         EzPickle.__init__(self, *args, **kwargs)
         self.env = _env(*args, **kwargs)
         self.render_mode = self.env.render_mode
-        self.agents = ["walker_" + str(r) for r in range(self.env.num_agents)]
+        self.agents = ["walker_" + str(r) for r in range(self.env.n_walkers)]
         self.possible_agents = self.agents[:]
-        self.agent_name_mapping = dict(zip(self.agents, list(range(self.num_agents))))
+        self.agent_name_mapping = dict(
+            zip(self.agents, list(range(self.env.n_walkers)))
+        )
         self._agent_selector = agent_selector(self.agents)
         # spaces
         self.action_spaces = dict(zip(self.agents, self.env.action_space))
diff --git a/pettingzoo/sisl/multiwalker/multiwalker_base.py b/pettingzoo/sisl/multiwalker/multiwalker_base.py
index 3ff961237..3da9a1260 100644
--- a/pettingzoo/sisl/multiwalker/multiwalker_base.py
+++ b/pettingzoo/sisl/multiwalker/multiwalker_base.py
@@ -333,7 +333,6 @@ def __init__(
         self._seed()
         self.setup()
         self.screen = None
-        self.agent_list = list(range(self.n_walkers))
         self.last_rewards = [0 for _ in range(self.n_walkers)]
         self.last_dones = [False for _ in range(self.n_walkers)]
         self.last_obs = [None for _ in range(self.n_walkers)]
@@ -359,15 +358,12 @@ def setup(self):
             BipedalWalker(self.world, init_x=sx, init_y=init_y, seed=self.seed_val)
             for sx in self.start_x
         ]
-        self.num_agents = len(self.walkers)
         self.observation_space = [agent.observation_space for agent in self.walkers]
         self.action_space = [agent.action_space for agent in self.walkers]
 
         self.package_scale = self.n_walkers / 1.75
         self.package_length = PACKAGE_LENGTH / SCALE * self.package_scale
 
-        self.total_agents = self.n_walkers
-
         self.prev_shaping = np.zeros(self.n_walkers)
         self.prev_package_shaping = 0.0
 
@@ -534,7 +530,7 @@ def get_last_rewards(self):
         )
 
     def get_last_dones(self):
-        return dict(zip(self.agent_list, self.last_dones))
+        return dict(zip(list(range(self.n_walkers)), self.last_dones))
 
     def get_last_obs(self):
         return dict(
@@ -692,7 +688,8 @@ def render(self, close=False):
         self.surf = pygame.transform.flip(self.surf, False, True)
         self.screen.blit(self.surf, (-self.scroll * render_scale - offset, 0))
         if self.render_mode == "human":
-            pygame.display.flip()
+            pygame.event.pump()
+            pygame.display.update()
         elif self.render_mode == "rgb_array":
             return np.transpose(
                 np.array(pygame.surfarray.pixels3d(self.screen)), axes=(1, 0, 2)
diff --git a/pettingzoo/sisl/pursuit/pursuit_base.py b/pettingzoo/sisl/pursuit/pursuit_base.py
index 7b31d1fa1..8ba3be943 100644
--- a/pettingzoo/sisl/pursuit/pursuit_base.py
+++ b/pettingzoo/sisl/pursuit/pursuit_base.py
@@ -417,7 +417,8 @@ def render(self):
         new_observation = np.copy(observation)
         del observation
         if self.render_mode == "human":
-            pygame.display.flip()
+            pygame.event.pump()
+            pygame.display.update()
         return (
             np.transpose(new_observation, axes=(1, 0, 2))
             if self.render_mode == "rgb_array"
diff --git a/pettingzoo/sisl/waterworld/waterworld_base.py b/pettingzoo/sisl/waterworld/waterworld_base.py
index d2a53a1e0..00cfbacb1 100644
--- a/pettingzoo/sisl/waterworld/waterworld_base.py
+++ b/pettingzoo/sisl/waterworld/waterworld_base.py
@@ -741,7 +741,8 @@ def render(self):
         del observation
 
         if self.render_mode == "human":
-            pygame.display.flip()
+            pygame.event.pump()
+            pygame.display.update()
         return (
             np.transpose(new_observation, axes=(1, 0, 2))
             if self.render_mode == "rgb_array"