Manim

数学动画制作

开始

启动新项目

manim init project manim-project --default

更改main.py

from manim import *


class CreateCircle(Scene):
    def construct(self):
        circle = Circle()  
        circle.set_fill(PINK, opacity=0.5)  
        self.play(Create(circle))  

渲染

manim -pql main.py

Scene

Manim的画布类

Manim的场景一般都需要继承这个类所有的动画必须impl它的construct方法

class MyScene(Scene):
	def construct(self):
		self.play(Write(Text("Hello World!")))

方法

play: 播放动画
pause: 暂停
wait: 停止

Mobject

可以显示的基础类它的点的类型是numpy.ndarray

简单的形状 Circle Arrow Rectangle 都是Mobject

默认情况下 Mobject创建的地方都是屏幕中心在构建时可以使用移动的函数进行平移

方法

add(Mobject): 添加子Mobject
remove(Mobject): 删除子Mobject
shift(vec): 按照指定向量平移

LEFT UP RIGHT DOWN是四个垂直方向的向量

circle = Circle()
square = Square()
triangle = Triangle()

circle.shift(LEFT)
square.shift(UP)
triangle.shift(RIGHT)

move_to(vec): 将中心移动Mobject到某个 Point3D 点。
next_to(mobject,vec): 放在object旁边的vec方向

circle = Circle()
square = Square()
triangle = Triangle()
		
circle.move_to(LEFT * 2)
square.next_to(circle, LEFT)
triangle.align_to(circle, LEFT)

self.add(circle, square, triangle)
self.wait(1)

set_fill(color=None,opacity=none,family=True): 设置图形的填充颜色和不透明度

family=True时子Mobject也会应用

set_troke(color=None,width,opacity): 设置边框

对象

Text

文本对象

Do

点对象

Circle

圆

Square

正方形

Rectangle

菱形

Axes

坐标轴

Axes(x_range,y_range,x_length,y_length)

变换函数

Transform(m1,m2)

m1变形m2

FadeIn(m)

淡入

FadeOut(m)

淡出

Rotate(m,angle)

就地旋转

ScaleInPlace(m,factor)

就地缩放

GrowFromCenter(m)

从中心长出来

GrowArrow(m)

画箭头

ShowCreation(m)

手绘

示例

泰勒展开

import math
from manim import *

class DrawSin(Scene):
    def construct(self):
        # 创建坐标轴
        axes = Axes(
            x_range=[-10, 10, 1],   # x轴范围
            y_range=[-10, 10, 1],  # y轴范围
            x_length=8,
            y_length=8,
            tips=False,
        )
        plane = NumberPlane()
        self.play(Create(plane))

        sin_curve = axes.plot(lambda x: np.sin(x), color=BLUE)


        self.play(Create(axes))
        self.play(Write(sin_curve))
        self.wait(1)

        one = axes.plot(lambda x: x,color=PINK)
        self.play(Write(one))
        self.wait(0.5)

        two = axes.plot(lambda x: x - x**3 /6,color=PINK)
        self.play(ReplacementTransform(one,two))
        self.wait(0.5)

        three = axes.plot(lambda x: x - x**3 /6 + x**5/120,color=PINK)
        self.play(ReplacementTransform(two,three))
        self.wait(0.5)