Have Transform only copy target_mobject if it must

manimlib/animation/fading.py

@@ -36,7 +36,7 @@ class Fade(Transform):
 
 class FadeIn(Fade):
     def create_target(self) -> Mobject:
-        return self.mobject
+        return self.mobject.copy()
 
     def create_starting_mobject(self) -> Mobject:
         start = super().create_starting_mobject()

manimlib/animation/growing.py

@@ -26,7 +26,7 @@ class GrowFromPoint(Transform):
         super().__init__(mobject, **kwargs)
 
     def create_target(self) -> Mobject:
-        return self.mobject
+        return self.mobject.copy()
 
     def create_starting_mobject(self) -> Mobject:
         start = super().create_starting_mobject()

manimlib/animation/transform.py

@@ -54,12 +54,16 @@ class Transform(Animation):
     def begin(self) -> None:
         self.target_mobject = self.create_target()
         self.check_target_mobject_validity()
-        # Use a copy of target_mobject for the align_data_and_family
-        # call so that the actual target_mobject stays
-        # preserved, since calling allign_data will potentially
-        # change the structure of both arguments
-        self.target_copy = self.target_mobject.copy()
-        self.mobject.align_data_and_family(self.target_copy)
+
+        if self.mobject.is_aligned_with(self.target_mobject):
+            self.target_copy = self.target_mobject
+        else:
+            # Use a copy of target_mobject for the align_data_and_family
+            # call so that the actual target_mobject stays
+            # preserved, since calling align_data will potentially
+            # change the structure of both arguments
+            self.target_copy = self.target_mobject.copy()
+            self.mobject.align_data_and_family(self.target_copy)
         super().begin()
         if not self.mobject.has_updaters:
             self.mobject.lock_matching_data(

manimlib/mobject/mobject.py

@@ -1672,6 +1672,16 @@ class Mobject(object):
 
     # Alignment
 
+    def is_aligned_with(self, mobject: Mobject) -> bool:
+        if len(self.data) != len(mobject.data):
+            return False
+        if len(self.submobjects) != len(mobject.submobjects):
+            return False
+        return all(
+            sm1.is_aligned_with(sm2)
+            for sm1, sm2 in zip(self.submobjects, mobject.submobjects)
+        )
+
     def align_data_and_family(self, mobject: Mobject) -> Self:
         self.align_family(mobject)
         self.align_data(mobject)