Class: Homotopy

Defined in: animation/movement/Homotopy.ts:112

General homotopy animation that transforms every point on a mobject using a function f(x, y, z, t) => [x', y', z'] where t goes from 0 to 1.

Extends

• Animation

Constructors

Constructor

new Homotopy(mobject, options): Homotopy

Defined in: animation/movement/Homotopy.ts:125

Parameters

mobject

Mobject

options

HomotopyOptions

Returns

Homotopy

Overrides

Animation.constructor

Properties

_hasBegun

protected _hasBegun: boolean = false

Defined in: animation/Animation.ts:49

Track if begin() has been called

Inherited from

Animation._hasBegun

---

_isFinished

protected _isFinished: boolean = false

Defined in: animation/Animation.ts:46

Whether the animation has finished

Inherited from

Animation._isFinished

---

_startTime

protected _startTime: number = null

Defined in: animation/Animation.ts:43

Time when the animation started (set by Timeline)

Inherited from

Animation._startTime

---

duration

readonly duration: number

Defined in: animation/Animation.ts:37

Duration of the animation in seconds

Inherited from

Animation.duration

---

homotopyFunc

readonly homotopyFunc: HomotopyFunction

Defined in: animation/movement/Homotopy.ts:114

The homotopy function

---

mobject

readonly mobject: Mobject

Defined in: animation/Animation.ts:34

The mobject being animated

Inherited from

Animation.mobject

---

rateFunc

readonly rateFunc: RateFunction

Defined in: animation/Animation.ts:40

Rate function controlling the animation's pacing

Inherited from

Animation.rateFunc

---

remover

remover: boolean = false

Defined in: animation/Animation.ts:55

If true, the scene will remove this mobject after the animation finishes. Used by FadeOut (like Python manim's remover=True).

Inherited from

Animation.remover

Accessors

startTime

Get Signature

get startTime(): number

Defined in: animation/Animation.ts:220

Get the start time of this animation (set by Timeline)

Returns

number

Set Signature

set startTime(time): void

Defined in: animation/Animation.ts:227

Set the start time of this animation (used by Timeline)

Parameters

time

number

Returns

void

Inherited from

Animation.startTime

Methods

begin()

begin(): void

Defined in: animation/movement/Homotopy.ts:133

Store the original points at animation start

Returns

void

Overrides

Animation.begin

---

cleanUpFromScene()

cleanUpFromScene(scene): void

Defined in: animation/Animation.ts:141

Hook called by Scene after the animation finishes, before the next play(). Default: removes mobject if remover is set (FadeOut, Write({remover:true})). Override for animations that need to mutate scene membership — e.g. ReplacementTransform swaps source for target.

Parameters

scene

AnimationScene

Returns

void

Inherited from

Animation.cleanUpFromScene

---

finish()

finish(): void

Defined in: animation/movement/Homotopy.ts:182

Ensure the final state is exact

Returns

void

Overrides

Animation.finish

---

interpolate()

interpolate(alpha): void

Defined in: animation/movement/Homotopy.ts:155

Apply the homotopy at the given progress value.

The function is evaluated in WORLD space: stored points are local, so each is lifted through the world matrix before the call and pushed back through its inverse afterwards. For an untransformed mobject world === local, so this reduces to the plain transform.

Parameters

alpha

number

Returns

void

Overrides

Animation.interpolate

---

isFinished()

isFinished(): boolean

Defined in: animation/Animation.ts:181

Check if the animation has finished

Returns

boolean

Inherited from

Animation.isFinished

---

reset()

reset(): void

Defined in: animation/Animation.ts:190

Reset the animation to its initial state. Restores the mobject to its pre-animation visual state so that re-seeking (especially backward) produces correct results.

Returns

void

Inherited from

Animation.reset

---

update()

update(_dt, currentTime): void

Defined in: animation/Animation.ts:158

Update the animation for the current frame.

Parameters

_dt

number

Time delta since last frame (unused, but available for subclasses)

currentTime

number

Current time in the timeline

Returns

void

Inherited from

Animation.update