From eb7f1e21a31ca2620cc10b8a0d01cf5df888030e Mon Sep 17 00:00:00 2001
From: Grant Sanderson <grant@3blue1brown.com>
Date: Fri, 8 Feb 2019 16:50:48 -0800
Subject: [PATCH] Fixed Succession to work when animations share a mobject

---
 manimlib/animation/composition.py | 32 +++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/manimlib/animation/composition.py b/manimlib/animation/composition.py
index a585c2d5..8c7f5b2a 100644
--- a/manimlib/animation/composition.py
+++ b/manimlib/animation/composition.py
@@ -2,8 +2,10 @@ import numpy as np
 
 from manimlib.animation.animation import Animation
 from manimlib.mobject.mobject import Group
+from manimlib.utils.bezier import integer_interpolate
 from manimlib.utils.bezier import interpolate
 from manimlib.utils.config_ops import digest_config
+from manimlib.utils.iterables import remove_list_redundancies
 from manimlib.utils.rate_functions import linear
 from manimlib.utils.rate_functions import squish_rate_func
 
@@ -13,7 +15,7 @@ class AnimationGroup(Animation):
         # If None, this defaults to the sum of all
         # internal animations
         "run_time": None,
-        "rate_functions": linear,
+        "rate_func": linear,
         # If 0, all animations are played at once.
         # If 1, all are played successively.
         # If >0 and <1, they start at lagged times
@@ -23,7 +25,9 @@ class AnimationGroup(Animation):
 
     def __init__(self, *animations, **kwargs):
         self.animations = animations
-        self.group = Group(*[anim.mobject for anim in animations])
+        self.group = Group(*remove_list_redundancies(
+            [anim.mobject for anim in animations]
+        ))
         Animation.__init__(self, self.group, **kwargs)
         self.init_run_time()
 
@@ -97,6 +101,30 @@ class Succession(AnimationGroup):
         "lag_ratio": 1,
     }
 
+    def __init__(self, *animations, **kwargs):
+        self.active_animation = animations[0]
+        super().__init__(*animations, **kwargs)
+
+    def begin(self):
+        self.active_animation.begin()
+
+    def finish(self):
+        self.active_animation.finish()
+
+    def update_mobjects(self, dt):
+        self.active_animation.update_mobjects(dt)
+
+    def interpolate(self, alpha):
+        index, subalpha = integer_interpolate(
+            0, len(self.animations), alpha
+        )
+        animation = self.animations[index]
+        if animation is not self.active_animation:
+            self.active_animation.finish()
+            animation.begin()
+            self.active_animation = animation
+        animation.interpolate(subalpha)
+
 
 class LaggedStart(AnimationGroup):
     CONFIG = {