manim（manim 命令行）

Manim

Build mathematical animations programmatically using Python. Manim renders scenes to video files with precise control over every visual element.

Quick Start

from manim import *

class MyScene(Scene):
    def construct(self):
        # Create objects
        circle = Circle(color=BLUE)
        text = MathTex(r"e^{i\pi} + 1 = 0")

        # Animate
        self.play(Create(circle))
        self.play(Write(text))
        self.wait(1)
        self.play(FadeOut(circle, text))

Run with: manim -pql scene.py MyScene

Workflow

1. Define a Scene class inheriting from Scene (or ThreeDScene for 3D)
2. Implement construct() method
3. Create Mobjects (mathematical objects) - shapes, text, graphs
4. Animate with self.play() - use animation classes like Create, Transform, FadeIn
5. Render using CLI: manim -pqh scene.py SceneName

Core Concepts

Mobjects

All visible objects inherit from Mobject. Common types:

• Geometry: Circle, Square, Line, Arrow, Polygon
• Text: Text, MathTex, Tex
• Graphs: Axes, NumberPlane, FunctionGraph
• 3D: Sphere, Cube, ThreeDAxes
• Groups: VGroup to combine objects

Animations

Pass to self.play():

• Creation: Create, Write, FadeIn, GrowFromCenter
• Transform: Transform, ReplacementTransform, MoveToTarget
• Indication: Indicate, Flash, Circumscribe
• Removal: FadeOut, Uncreate

Positioning

obj.move_to(ORIGIN)          # Move to point
obj.shift(RIGHT * 2)         # Relative shift
obj.next_to(other, UP)       # Position relative to another
obj.align_to(other, LEFT)    # Align edge

Animation Parameters

self.play(Create(obj), run_time=2)           # Duration
self.play(Create(obj), rate_func=smooth)     # Easing
self.play(anim1, anim2)                       # Simultaneous
self.play(Succession(anim1, anim2))          # Sequential
self.play(LaggedStart(*anims, lag_ratio=0.5)) # Staggered

Common Patterns

Mathematical Equation

eq = MathTex(r"\int_0^1 x^2 \, dx = \frac{1}{3}")
self.play(Write(eq))

Function Graph

axes = Axes(x_range=[-3, 3], y_range=[-1, 5])
graph = axes.plot(lambda x: x**2, color=BLUE)
label = axes.get_graph_label(graph, label="x^2")
self.play(Create(axes), Create(graph), Write(label))

Value Tracking (Animated Numbers)

tracker = ValueTracker(0)
number = DecimalNumber(0).add_updater(
    lambda m: m.set_value(tracker.get_value())
)
self.add(number)
self.play(tracker.animate.set_value(10), run_time=2)

3D Scene

class My3D(ThreeDScene):
    def construct(self):
        axes = ThreeDAxes()
        sphere = Sphere()
        self.set_camera_orientation(phi=75*DEGREES, theta=45*DEGREES)
        self.play(Create(axes), Create(sphere))
        self.begin_ambient_camera_rotation(rate=0.2)
        self.wait(3)

Transform Between States

circle = Circle()
square = Square()
self.play(Create(circle))
self.play(Transform(circle, square))  # circle becomes square

CLI Reference

manim scene.py SceneName      # Render scene
manim -p scene.py SceneName   # Preview after render
manim -s scene.py SceneName   # Save last frame only

# Quality flags
-ql  # Low (480p @ 15fps)
-qm  # Medium (720p @ 30fps)
-qh  # High (1080p @ 60fps)
-qk  # 4K (2160p @ 60fps)

Key Gotchas

1. Transform mutates first object: After Transform(a, b), reference a (now looks like b), not b
2. Use ReplacementTransform to avoid confusion: replaces a with b in scene
3. Mobjects are mutable: Use .copy() to avoid unintended changes
4. LaTeX requires r prefix: MathTex(r"\frac{1}{2}") not MathTex("\frac{1}{2}")
5. 3D requires ThreeDScene: Regular Scene won't render 3D properly
6. self.add() is instant: Use self.play(FadeIn(...)) for animated appearance

References

• Full API (animations, mobjects, scenes, colors, constants): See references/api.md
• Quick lookup (tables, patterns, CLI): See references/quick-reference.md