Moved more of animation cleanup handling to the animations themselves

animation/animation.py

@@ -118,8 +118,11 @@ class Animation(object):
     def is_remover(self):
         return self.remover
 
-    def clean_up(self):
+    def clean_up(self, surrounding_scene = None):
         self.update(1)
+        if self.is_remover() and surrounding_scene is not None:
+            surrounding_scene.remove(self.mobject)
+        return self
 
 
 def sync_animation_run_times_and_rate_funcs(*animations, **kwargs):

animation/transform.py

@@ -55,6 +55,12 @@ class Transform(Animation):
         submob.interpolate(start, end, alpha, self.path_func)
         return self
 
+    def clean_up(self, surrounding_scene = None):
+        Animation.clean_up(self, surrounding_scene)
+        if self.replace_mobject_with_target_in_scene and surrounding_scene is not None:
+            surrounding_scene.remove(self.mobject)
+            surrounding_scene.add(self.original_target_mobject)
+
 class ReplacementTransform(Transform):
     CONFIG = {
         "replace_mobject_with_target_in_scene" : True,
@@ -147,7 +153,8 @@ class FadeOut(Transform):
             target.set_fill(opacity = 0)
         Transform.__init__(self, mobject, target, **kwargs)
 
-    def clean_up(self):
+    def clean_up(self, surrounding_scene = None):
+        Transform.clean_up(self, surrounding_scene)
         self.update(0)
 
 class FadeIn(Transform):

scene/scene.py

@@ -17,7 +17,7 @@ from tk_scene import TkSceneRoot
 from mobject import Mobject, VMobject
 from animation import Animation
 from animation.animation import sync_animation_run_times_and_rate_funcs
-from animation.transform import MoveToTarget, Transform
+from animation.transform import MoveToTarget
 
 class Scene(object):
     CONFIG = {
@@ -142,6 +142,20 @@ class Scene(object):
             lambda m : m not in mobjects_to_remove,
             self.mobjects
         )
+        self.remove_mobjects_without_family_on_screen()
+        return self
+
+    def remove_mobjects_without_family_on_screen(self):
+        def should_keep(mobject):
+            if mobject.get_num_points() > 0:
+                return True
+            num_family_members_among_mobjects = sum([
+                submob in self.mobjects
+                for submob in mobject.submobject_family()
+            ])
+            return num_family_members_among_mobjects > 1
+
+        self.mobjects = filter(should_keep, self.mobjects)
         return self
 
     def bring_to_front(self, *mobjects):
@@ -266,13 +280,7 @@ class Scene(object):
 
     def clean_up_animations(self, *animations):
         for animation in animations:
-            animation.clean_up()
-            if animation.is_remover():
-                self.remove(animation.mobject)
-            if isinstance(animation, Transform) :
-                if animation.replace_mobject_with_target_in_scene:
-                    self.remove(animation.mobject)
-                    self.add(animation.original_target_mobject)
+            animation.clean_up(self)
         return self
 
     def get_mobjects_from_last_animation(self):

topics/characters.py

@@ -329,6 +329,7 @@ class RemovePiCreatureBubble(AnimationGroup):
     CONFIG = {
         "target_mode" : "plain",
         "look_at_arg" : None,
+        "remover" : True,
     }
     def __init__(self, pi_creature, **kwargs):
         assert hasattr(pi_creature, "bubble")
@@ -346,9 +347,12 @@ class RemovePiCreatureBubble(AnimationGroup):
             FadeOut(pi_creature.bubble.content),
         )
 
-    def clean_up(self):
-        AnimationGroup.clean_up(self)
+    def clean_up(self, surrounding_scene = None):
+        AnimationGroup.clean_up(self, surrounding_scene)
         self.pi_creature.bubble = None
+        if surrounding_scene is not None:
+            surrounding_scene.add(self.pi_creature)
+
     
 
 class PiCreatureScene(Scene):