fading

class janim.anims.fading.Fade(item: Item, shift: Vect = array([0., 0., 0.]), scale: float = 1.0, *, about_point: Vect | None = None, about_edge: Vect = array([0., 0., 0.]), path_arc: float = 0, path_arc_axis: Vect = array([0., 0., 1.]), path_func: PathFunc = None, become_at_end: bool = False, root_only: bool = False, **kwargs)

基类：DataUpdater

FadeIn 和 FadeOut 的基类

class janim.anims.fading.FadeIn(item: Item, shift: Vect = array([0., 0., 0.]), scale: float = 1.0, *, about_point: Vect | None = None, about_edge: Vect = array([0., 0., 0.]), path_arc: float = 0, path_arc_axis: Vect = array([0., 0., 1.]), path_func: PathFunc = None, become_at_end: bool = False, root_only: bool = False, **kwargs)

基类：Fade

淡入

• 可以使用 shift 指定淡入位移

• 可以使用 scale 指定淡入缩放

FadeInExample

from janim.imports import *

class FadeInExample(Timeline):
    def construct(self):
        group = Group(
            Square(fill_alpha=0.5),
            Circle(fill_alpha=0.5),
            Text('Text', font_size=48),
            color=BLUE
        )
        group.points.arrange(buff=LARGE_BUFF)

        self.play(
            FadeIn(group),
            duration=2
        )

class janim.anims.fading.FadeOut(item: Item, shift: Vect = array([0., 0., 0.]), scale: float = 1.0, show_at_end: float = False, **kwargs)

基类：Fade

淡出

• 可以使用 shift 指定淡出位移

• 可以使用 scale 指定淡出缩放

FadeOutExample

from janim.imports import *

class FadeOutExample(Timeline):
    def construct(self):
        group = Group(
            Square(fill_alpha=0.5),
            Circle(fill_alpha=0.5),
            Text('Text', font_size=48),
            color=BLUE
        )
        group.points.arrange(buff=LARGE_BUFF)

        self.play(
            FadeOut(group),
            duration=2
        )

class janim.anims.fading.FadeInFromPoint(item: Item, point: Vect, **kwargs)

基类：FadeIn

FadeInFromPointExample

from janim.imports import *

class FadeInFromPointExample(Timeline):
    def construct(self):
        items = Group(
            Circle(),
            Circle(fill_alpha=1),
            Text('Text', font_size=48)
        )
        items.points.scale(1.5)
        items.points.arrange(RIGHT, buff=2)

        self.forward()
        self.play(
            *[FadeInFromPoint(item, UP*3) for item in items]
        )
        self.forward()

class janim.anims.fading.FadeOutToPoint(item: Item, point: Vect, **kwargs)

基类：FadeOut

FadeOutToPointExample

from janim.imports import *

class FadeOutToPointExample(Timeline):
    def construct(self):
        items = Group(
            Circle(),
            Circle(fill_alpha=1),
            Text('Text', font_size=48)
        ).show()
        items.points.scale(1.5)
        items.points.arrange(RIGHT, buff=2)

        self.forward()
        self.play(
            *[FadeOutToPoint(item, DOWN*3) for item in items]
        )
        self.forward()