Remove duplicate items

[LinZezh1]

Motivation

In the Animation class, the get_all_mobjects_to_update method would cause duplicate Mobjects to be returned, and update was performed on all of them.

Proposed changes

Add items = list(set(items)) in the get_all_mobjects_to_update method of the Animation class to achieve the purpose of removing duplicate items.

Code and test

class AnimationIssue(ThreeDScene):

    def construct(self) -> None:
        day_texture = "https://upload.wikimedia.org/wikipedia/commons/thumb/4/4d/Whole_world_-_land_and_oceans.jpg/1280px-Whole_world_-_land_and_oceans.jpg"
        night_texture = "https://upload.wikimedia.org/wikipedia/commons/thumb/b/ba/The_earth_at_night.jpg/1280px-The_earth_at_night.jpg"
        sphere = Sphere(radius=RADIUS)

        surface = TexturedSurface(sphere, day_texture, night_texture)
        always_rotate(surface)
        self.play(FadeIn(surface, run_time=2))
        self.wait(3)

After running the above code, the Earth in the video will first rotate quickly and then decelerate. This is due to the get_all_mobjects_to_update method (TransForm.get_all_mobjects) in the Animation class returning duplicate mobjects(TransForm.get_all_mobjects.target_copy).

default.mp4

Therefore, I used the set function in the get_all_mobjects_to_update method of the Animation class to remove duplicate mobjects, which prevented the issue from occurring(fixed video)

default.mp4