Porting from GodotPorting from Godot

Legacy eases carry the names of Godot’s transitions and draw the same curves, so a ported tween moves as it did with Godot’s Tween. For most families, the composable In and Out flags draw them too.

Examples use using Godot; and using tweens.gd; in a Node method, with targets inside the scene tree.

Examples use the global Tweens class in a node script, with targets inside the scene tree.

Port a tween

Join the transition and the ease into one name: TransitionType.Elastic with EaseType.Out becomes EaseType.ElasticOut.

Godot's Tween

var tween = sprite.CreateTween();
tween.TweenProperty(sprite, "position", new Vector2(400, 180), 0.8)
    .SetTrans(Tween.TransitionType.Elastic)
    .SetEase(Tween.EaseType.Out);

tweens.gd

sprite.TweenPosition((400, 180), 0.8, EaseType.ElasticOut);

Godot eases in and out by default

A Godot tween that sets only the transition uses EaseType.InOut, so SetTrans(Tween.TransitionType.Sine) alone ports to EaseType.SineInOut. tweens.gd defaults to Linear.

Join the transition and the ease into one name: TRANS_ELASTIC with EASE_OUT becomes Tweens.Ease.ELASTIC_OUT.

Godot's Tween

var tween := sprite.create_tween()
tween.set_trans(Tween.TRANS_ELASTIC)
tween.set_ease(Tween.EASE_OUT)
tween.tween_property(sprite, "position", Vector2(400, 180), 0.8)

tweens.gd

var arrive := Tweens.position_2d([400, 180], 0.8, Tweens.Ease.ELASTIC_OUT)

Tweens.play(sprite, arrive)

Godot eases in and out by default

A Godot tween that sets only the transition uses EASE_IN_OUT, so set_trans(Tween.TRANS_SINE) alone ports to Tweens.Ease.SINE_IN_OUT. tweens.gd defaults to LINEAR.

Legacy eases

Legacy names

EaseType.SineIn, EaseType.BounceOut: Godot’s transition and ease in one name, with Godot’s curve. Use them to port motion unchanged.

In and Out flags

In.Sine, Out.Cubic, InOut.Back10: mix families, choose overshoot strength, and tune the join. Use them for new motion.

Each Godot transition has a legacy name per ease. Where a flag draws the same curve, either works:

Godot transition	Legacy names	Same curve with flags
Linear	Linear	InOut.Linear
Sine	SineIn, SineOut, SineInOut	In.Sine, Out.Sine, InOut.Sine
Quad	QuadIn, QuadOut, QuadInOut	In.Quad, Out.Quad, InOut.Quad
Cubic	CubicIn, CubicOut, CubicInOut	In.Cubic, Out.Cubic, InOut.Cubic
Quart	QuartIn, QuartOut, QuartInOut	In.Quart, Out.Quart, InOut.Quart
Quint	QuintIn, QuintOut, QuintInOut	In.Quint, Out.Quint, InOut.Quint
Expo	ExpoIn, ExpoOut, ExpoInOut	In.Expo, Out.Expo, InOut.Expo
Circ	CircIn, CircOut, CircInOut	In.Circ, Out.Circ, InOut.Circ
Back	BackIn, BackOut, BackInOut	In.Back10, Out.Back10, InOut.Back10
Elastic	ElasticIn, ElasticOut, ElasticInOut	None
Bounce	BounceIn, BounceOut, BounceInOut	None
Spring	None	None; see Spring and out-in

• Flags measure overshoot as a share of the range, so Godot’s Back is Back10. Elastic and Bounce flags are calibrated the same way; only their legacy names keep Godot’s shapes, such as EaseType.BounceOut’s 25% first rebound.
• Expo matches to within 0.1% of the range: Godot offsets its Expo curves slightly.
• Don’t combine legacy names with flags.
• EaseType.Linear, zero, is the default.

Legacy names

Tweens.Ease.SINE_IN, Tweens.Ease.BOUNCE_OUT: Godot’s transition and ease in one name, with Godot’s curve. Use them to port motion unchanged.

In and Out flags

In.SINE, Out.CUBIC, InOut.BACK10: mix families, choose overshoot strength, and tune the join. Use them for new motion.

Each Godot transition has a legacy name per ease in Tweens.Ease. Where a flag draws the same curve, either works:

Godot transition	Legacy names	Same curve with flags
TRANS_LINEAR	LINEAR	InOut.LINEAR
TRANS_SINE	SINE_IN, SINE_OUT, SINE_IN_OUT	In.SINE, Out.SINE, InOut.SINE
TRANS_QUAD	QUAD_IN, QUAD_OUT, QUAD_IN_OUT	In.QUAD, Out.QUAD, InOut.QUAD
TRANS_CUBIC	CUBIC_IN, CUBIC_OUT, CUBIC_IN_OUT	In.CUBIC, Out.CUBIC, InOut.CUBIC
TRANS_QUART	QUART_IN, QUART_OUT, QUART_IN_OUT	In.QUART, Out.QUART, InOut.QUART
TRANS_QUINT	QUINT_IN, QUINT_OUT, QUINT_IN_OUT	In.QUINT, Out.QUINT, InOut.QUINT
TRANS_EXPO	EXPO_IN, EXPO_OUT, EXPO_IN_OUT	In.EXPO, Out.EXPO, InOut.EXPO
TRANS_CIRC	CIRC_IN, CIRC_OUT, CIRC_IN_OUT	In.CIRC, Out.CIRC, InOut.CIRC
TRANS_BACK	BACK_IN, BACK_OUT, BACK_IN_OUT	In.BACK10, Out.BACK10, InOut.BACK10
TRANS_ELASTIC	ELASTIC_IN, ELASTIC_OUT, ELASTIC_IN_OUT	None
TRANS_BOUNCE	BOUNCE_IN, BOUNCE_OUT, BOUNCE_IN_OUT	None
TRANS_SPRING	None	None; see Spring and out-in

• Flags measure overshoot as a share of the range, so Godot’s Back is BACK10. Elastic and Bounce flags are calibrated the same way; only their legacy names keep Godot’s shapes, such as Tweens.Ease.BOUNCE_OUT’s 25% first rebound.
• Expo matches to within 0.1% of the range: Godot offsets its Expo curves slightly.
• Don’t combine legacy names with flags.
• Tweens.Ease.LINEAR, zero, is the default.

Spring and out-in

tweens.gd has no Spring transition and no out-in ease. To keep these curves, let Godot sample them in an ease function:

var arrive = new Tweens.Position2D((400, 180), 0.8)
{
    EaseFunction = t => Tween.InterpolateValue(0f, 1f, t, 1,
        Tween.TransitionType.Spring, Tween.EaseType.Out).AsSingle(),
};

sprite.Tween(arrive);

Tween.InterpolateValue samples any transition and ease, including Tween.EaseType.OutIn.

var arrive := Tweens.position_2d([400, 180], 0.8)
arrive.ease_function = func(t: float) -> float:
    return Tween.interpolate_value(0.0, 1.0, t, 1.0, Tween.TRANS_SPRING, Tween.EASE_OUT)

Tweens.play(sprite, arrive)

Tween.interpolate_value() samples any transition and ease, including Tween.EASE_OUT_IN.

Coming from Godot's TweenPort loops, delays, callbacks, and signals.

Easing playgroundCompare every family and mix an In with a different Out.

The easing reference lists every flag, and Functions explains ease functions.

Coming from Godot's TweenPort loops, delays, callbacks, and signals.

Easing playgroundCompare every family and mix an In with a different Out.

The easing reference lists every flag, and Functions explains ease functions.