Scenes - ManimVTK

What is a Scene?

A Scene is the fundamental building block of ManimVTK. It’s a container for your animation that manages:

Mobjects (visual objects)
Animations (movements and transformations)
Camera (viewpoint and perspective)
Rendering (video output and VTK export)

Every ManimVTK animation starts with a scene class.

Basic Scene Structure

from manimvtk import *

class MyScene(Scene):
    def construct(self):
        # Your animation code goes here
        pass

Key components:

Import: from manimvtk import *
Class definition: Inherit from Scene
construct() method: Where you build your animation

The construct() Method

The construct() method is where all your animation logic lives:

class SimpleAnimation(Scene):
    def construct(self):
        # Create objects
        circle = Circle(radius=1, color=BLUE)
        
        # Add to scene
        self.add(circle)
        
        # Animate
        self.play(circle.animate.scale(2))
        
        # Wait
        self.wait()

The construct() method is called automatically when you render the scene

Scene Types

ManimVTK provides several scene types for different use cases:

Scene
ThreeDScene
MovingCameraScene
ZoomedScene

Basic 2D scene - Default scene type

class Basic2D(Scene):
    def construct(self):
        square = Square()
        self.play(Create(square))

Use for:

2D animations
Graphs and plots
Educational diagrams

3D scene with camera controls

class Basic3D(ThreeDScene):
    def construct(self):
        # Set camera angle
        self.set_camera_orientation(phi=60 * DEGREES, theta=30 * DEGREES)
        
        # Add 3D object
        sphere = Sphere()
        self.play(Create(sphere))

Use for:

3D visualizations
Surfaces and parametric objects
Scientific simulations

Scene with movable camera

class CameraMove(MovingCameraScene):
    def construct(self):
        square = Square()
        self.add(square)
        
        # Zoom in
        self.play(self.camera.frame.animate.scale(0.5))

Use for:

Zooming animations
Pan and scan effects
Focus on details

Scene with picture-in-picture zoom

class ZoomExample(ZoomedScene):
    def construct(self):
        # Main content
        dots = VGroup(*[Dot() for _ in range(10)]).arrange_in_grid()
        self.add(dots)
        
        # Create zoomed camera
        zoomed_camera = self.zoomed_camera
        # Activate zoom
        self.activate_zooming()

Use for:

Detail views
Magnification effects
Complex diagrams

Adding Objects to a Scene

Using add()

Instantly add objects without animation:

class AddExample(Scene):
    def construct(self):
        circle = Circle()
        square = Square()
        
        # Add instantly (no animation)
        self.add(circle, square)
        self.wait()

Using play()

Add objects with animation:

class PlayExample(Scene):
    def construct(self):
        circle = Circle()
        
        # Add with creation animation
        self.play(Create(circle))
        self.wait()

Adding Multiple Objects

class MultipleObjects(Scene):
    def construct(self):
        # Create a group
        shapes = VGroup(
            Circle(),
            Square(),
            Triangle()
        ).arrange(RIGHT, buff=1)
        
        # Add all at once
        self.play(Create(shapes))
        self.wait()

Scene Methods

Animation Control

play()

Play one or more animations:

self.play(Create(circle))
self.play(Transform(square, circle))

# Multiple animations simultaneously
self.play(
    Create(circle),
    FadeIn(text)
)

wait()

Pause the animation:

self.wait()  # Wait 1 second (default)
self.wait(2)  # Wait 2 seconds
self.wait(0.5)  # Wait 0.5 seconds

add()

Add objects without animation:

self.add(circle)
self.add(square, triangle)  # Multiple objects

remove()

Remove objects from scene:

self.remove(circle)
self.remove(square, triangle)

Camera Control (ThreeDScene)

set_camera_orientation()

Set the initial camera position:

self.set_camera_orientation(
    phi=60 * DEGREES,    # Vertical angle
    theta=30 * DEGREES,  # Horizontal angle
    distance=8           # Distance from origin
)

begin_ambient_camera_rotation()

Start continuous camera rotation:

self.begin_ambient_camera_rotation(rate=0.1)
self.wait(5)  # Rotate for 5 seconds
self.stop_ambient_camera_rotation()

move_camera()

Animate camera movement:

self.move_camera(
    phi=75 * DEGREES,
    theta=45 * DEGREES,
    run_time=2
)

Scene Lifecycle

Understanding the order of operations:

class LifecycleExample(Scene):
    def construct(self):
        # 1. Object creation
        circle = Circle()
        
        # 2. Add to scene (instant)
        self.add(circle)
        
        # 3. Animations
        self.play(circle.animate.scale(2))
        
        # 4. Wait/pause
        self.wait()
        
        # 5. More animations
        self.play(FadeOut(circle))
        
        # 6. Scene ends (automatic rendering)

Rendering process:

construct() method executes
Animations are recorded
Frames are generated
Video is encoded
VTK export (if requested)

Configuration

In Scene Class

class ConfiguredScene(Scene):
    def construct(self):
        # Access config
        print(f"Frame rate: {config.frame_rate}")
        print(f"Resolution: {config.pixel_width}x{config.pixel_height}")
        
        # Your animation
        circle = Circle()
        self.play(Create(circle))

Via Command Line

# Set quality
manimvtk -qh scene.py MyScene  # High quality

# Set frame rate
manimvtk -r 60 scene.py MyScene  # 60 fps

# Set resolution
manimvtk --resolution 1920,1080 scene.py MyScene

Via Config File

Create manim.cfg:

[CLI]
quality = high
frame_rate = 60
background_color = BLACK

Common Patterns

Simple Animation

class SimplePattern(Scene):
    def construct(self):
        # Create → Animate → Remove
        obj = Circle()
        self.play(Create(obj))
        self.play(obj.animate.shift(RIGHT))
        self.play(FadeOut(obj))

Sequential Animations

class Sequential(Scene):
    def construct(self):
        objs = VGroup(*[Circle() for _ in range(3)])
        objs.arrange(RIGHT, buff=1)
        
        # Animate one by one
        for obj in objs:
            self.play(Create(obj))
        self.wait()

Simultaneous Animations

class Simultaneous(Scene):
    def construct(self):
        c1 = Circle().shift(LEFT)
        c2 = Circle().shift(RIGHT)
        
        # Both at the same time
        self.play(
            Create(c1),
            Create(c2)
        )

Build Up and Transform

class BuildAndTransform(Scene):
    def construct(self):
        # Build up
        circle = Circle()
        self.play(Create(circle))
        
        # Transform
        square = Square()
        self.play(Transform(circle, square))
        
        # Continue with transformed object
        self.play(circle.animate.rotate(PI/4))

Best Practices

Keep construct() organized

Break complex scenes into helper methods:

class OrganizedScene(Scene):
    def construct(self):
        self.intro()
        self.main_content()
        self.outro()
    
    def intro(self):
        title = Text("Introduction")
        self.play(Write(title))
        self.wait()
        self.play(FadeOut(title))
    
    def main_content(self):
        # Main animation logic
        pass
    
    def outro(self):
        # Closing
        pass

Use descriptive names

# Good
class QuadraticFunction(Scene):
    pass

# Avoid
class Test1(Scene):
    pass

Add wait() for clarity

Give viewers time to process:

self.play(Create(important_diagram))
self.wait(2)  # Let viewers see it
self.play(FadeOut(important_diagram))

Reuse objects

# Efficient
circle = Circle()
self.play(Create(circle))
self.play(circle.animate.shift(RIGHT))

# Less efficient
circle1 = Circle()
self.play(Create(circle1))
circle2 = circle1.copy().shift(RIGHT)
self.play(Transform(circle1, circle2))

Debugging Scenes

Print Debug Info

class DebugScene(Scene):
    def construct(self):
        circle = Circle()
        
        # Debug output
        print(f"Circle center: {circle.get_center()}")
        print(f"Circle color: {circle.get_color()}")
        
        self.add(circle)

Preview Frames

# Save last frame only (fast)
manimvtk -s scene.py MyScene

# Save all frames
manimvtk --save_sections scene.py MyScene

Use Lower Quality for Testing

# Fast preview
manimvtk -ql scene.py MyScene

# Final render
manimvtk -qh scene.py MyScene

Next Steps

Mobjects

Learn about creating and manipulating objects

Animations

Master animation techniques

Cameras

Control camera movement and perspective

Examples

Browse example scenes

​What is a Scene?

​Basic Scene Structure

​The construct() Method

​Scene Types

​Adding Objects to a Scene

​Using add()

​Using play()

​Adding Multiple Objects

​Scene Methods

​Animation Control

​Camera Control (ThreeDScene)

​Scene Lifecycle

​Configuration

​In Scene Class

​Via Command Line

​Via Config File

​Common Patterns

​Simple Animation

​Sequential Animations

​Simultaneous Animations

​Build Up and Transform

​Best Practices

​Debugging Scenes

​Print Debug Info

​Preview Frames

​Use Lower Quality for Testing

​Next Steps

Mobjects

Animations

Cameras

Examples

What is a Scene?

Basic Scene Structure

The construct() Method

Scene Types

Adding Objects to a Scene

Using add()

Using play()

Adding Multiple Objects

Scene Methods

Animation Control

Camera Control (ThreeDScene)

Scene Lifecycle

Configuration

In Scene Class

Via Command Line

Via Config File

Common Patterns

Simple Animation

Sequential Animations

Simultaneous Animations

Build Up and Transform

Best Practices

Debugging Scenes

Print Debug Info

Preview Frames

Use Lower Quality for Testing

Next Steps