Programming

Instantly hide or remove a Manim mobject in Python

Make a Manim mobject vanish instantly in Manim Python: clear updaters, call Scene.remove(obj), or set_opacity(0). Tips for non-animated hiding and cleanup.

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How can I make a Manim mobject disappear instantly (without any animation) when calling a method on it?

Example:

python
# utils.py
class mobject(VMobject): # it is also fine if it inherits from Mobject
 def disappear(self):
 # code here
 pass

# test.py
from utils import *

class test(Scene):
 def construct(self):
 m = mobject()
 self.add(m)
 m.disappear() # it should disappear instantly without any animation

How should disappear() be implemented so that the mobject is removed or hidden from the scene immediately when called? Are there recommended approaches or best practices (for example, removing the mobject from the scene, setting opacity, or other methods) to achieve an instant, non-animated disappearance in Manim?

In manim (manim python), the instant, non‑animated way to make a mobject vanish is to remove it from the Scene with Scene.remove(m) or, if you just need a quick visual hide, set the mobject’s opacity to 0 and clear its updaters. If you want a mobject method disappear() you can implement it to clear updaters, optionally call scene.remove(self) when a Scene is supplied, and fall back to self.set_opacity(0) when no Scene reference is available.

Contents

Instant disappearance in a manim Scene

Want the object gone immediately? Do it at the Scene level. The canonical, immediate (non-animated) approach is to call Scene.remove(m), which updates the Scene’s internal mobjects and foreground lists and makes the object stop being rendered or considered for future animations. See the Scene reference and the building blocks tutorial for the simple pattern of add/remove in construct().

Example (preferred, simplest):

python
class Test(Scene):
 def construct(self):
 m = mobject()
 self.add(m)
 # instant, non-animated removal:
 self.remove(m)

Notes:

  • Removing at the Scene level frees the renderer from drawing the object and prevents later animations from operating on it.
  • A “remover” animation like FadeOut will also remove the object after the animation finishes, but that is an animation — not instantaneous unless you explicitly use a 0-second play (generally unnecessary). See the FadeOut docs.

Implementing disappear() on a Mobject — manim documentation

If you prefer an API that calls a method on the mobject itself, give that method the option to accept the current Scene (recommended). Inside that method you should:

  • Clear updaters so the object can’t be re-created or changed by a running updater.
  • Optionally remove it from the Scene (best when you want it gone for good).
  • Optionally set opacity to 0 as a fallback (instant visual hide, but the object stays in the Scene’s lists).

Example implementation:

python
# utils.py
from manim import VMobject

class mobject(VMobject):
 def disappear(self, scene=None):
 # Stop any updaters so the object doesn't reappear
 self.clear_updaters()
 # Immediately hide visually (fallback if no Scene is provided)
 self.set_opacity(0)
 # If a Scene is supplied, remove the mobject from it (recommended)
 if scene is not None:
 scene.remove(self)

Usage options in your Scene:

python
class Test(Scene):
 def construct(self):
 m = mobject()
 self.add(m)

 # Option A (recommended): remove at the scene level
 self.remove(m)

 # Option B: call the object's method and pass the scene
 # m.disappear(self)

References: Mobject methods like set_opacity and the updater API are documented in the Mobject reference. The tutorial shows add/remove usage in context: building blocks tutorial.

Hide vs Remove: opacity vs scene.remove

Which technique should you use?

  • set_opacity(0) (hide)

  • Pros: Instant visual disappearance, simple, easy to bring back with set_opacity(1).

  • Cons: The mobject remains in Scene.mobjects and still consumes memory; it may still be targeted by future animations or affect layout calculations.

  • Use when you plan to reuse the object, or for a quick toggle.

  • scene.remove(m) (remove)

  • Pros: Removes the mobject from the scene’s lists so it won’t be drawn or animated any more; better for cleanup and memory.

  • Cons: If you want it back, you must re-add it to the Scene (self.add(m)).

  • Use when the object is truly done.

Important: clearing updaters is critical if the object has any updaters; otherwise an updater could redraw or mutate the object after you hide/remove it. Mobject updaters can be managed via the methods shown in the Mobject reference.

Practical examples and best practices

  • Recommended pattern: do removal at the Scene level unless the object owns the lifecycle and you explicitly pass the Scene into the method. It keeps responsibilities clear: Scene manages which mobjects are present; mobjects manage their visual state.

  • Example: immediate hide and reuse later

python
m.set_opacity(0) # instant hide
# ... later
m.set_opacity(1) # show again
  • Example: remove after a transform
    If you transform one object into another and the original remains, remove it after the animation:
python
self.play(ReplacementTransform(sq, ci))
self.remove(sq)

Community threads often show this pattern when Transform/ReplacementTransform leaves unexpected objects — see an example discussion on Reddit: https://www.reddit.com/r/manim/comments/zooszo/remove_object_after_using_transform/

  • Avoid hacks: trying to auto-discover the “current Scene” from inside a Mobject (stack inspection, globals) is brittle. Explicitly pass the Scene when needed.

  • Clean references: if the mobject holds large Python objects or references, set those attributes to None after removal to help GC.

Troubleshooting and gotchas

  • “I called m.disappear() but it’s still visible.”
    Likely causes: an updater re-drew it, or you used Mobject.remove (which removes submobjects) instead of Scene.remove. Solution: call self.clear_updaters() and use scene.remove(m) from the Scene.

  • “Transform left the original object behind.”
    Use ReplacementTransform for a one-to-one replacement, and/or remove the source object after the animation ends.

  • “I hid it with set_opacity(0) but performance still degrades.”
    Hiding doesn’t free resources — remove the mobject from the Scene if you need to reclaim memory or avoid processing.

  • “I want zero-latency removal inside construct() without extra play() calls.”
    Use self.remove(m) inside construct. That executes immediately and does not allocate animation frames.

Sources

Conclusion

For an instant, non-animated disappearance in manim, remove the mobject at the Scene level with Scene.remove(m) (best for cleanup) or clear updaters and set_opacity(0) for an immediate visual hide. If you implement disappear() on the mobject, accept an optional Scene argument and prefer calling scene.remove(self) after clearing updaters—otherwise use set_opacity(0) as a fallback.

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Instantly hide or remove a Manim mobject in Python