Enum EaseFunction

#[non_exhaustive]
pub enum EaseFunction {
    Linear,
    QuadraticIn,
    QuadraticOut,
    QuadraticInOut,
    CubicIn,
    CubicOut,
    CubicInOut,
    QuarticIn,
    QuarticOut,
    QuarticInOut,
    QuinticIn,
    QuinticOut,
    QuinticInOut,
    SmoothStepIn,
    SmoothStepOut,
    SmoothStep,
    SmootherStepIn,
    SmootherStepOut,
    SmootherStep,
    SineIn,
    SineOut,
    SineInOut,
    CircularIn,
    CircularOut,
    CircularInOut,
    ExponentialIn,
    ExponentialOut,
    ExponentialInOut,
    ElasticIn,
    ElasticOut,
    ElasticInOut,
    BackIn,
    BackOut,
    BackInOut,
    BounceIn,
    BounceOut,
    BounceInOut,
    Steps(usize, JumpAt),
    Elastic(f32),
}

Available on crate feature curve only.

Curve functions over the unit interval, commonly used for easing transitions.

EaseFunction can be used on its own to interpolate between 0.0 and 1.0. It can also be combined with EasingCurve to interpolate between other intervals and types, including vectors and rotations.

Example

sample the smoothstep function at various points. This will return None if the parameter is outside the unit interval.

let f = EaseFunction::SmoothStep;

assert_eq!(f.sample(-1.0), None);
assert_eq!(f.sample(0.0), Some(0.0));
assert_eq!(f.sample(0.5), Some(0.5));
assert_eq!(f.sample(1.0), Some(1.0));
assert_eq!(f.sample(2.0), None);

sample_clamped will clamp the parameter to the unit interval, so it always returns a value.

assert_eq!(f.sample_clamped(-1.0), 0.0);
assert_eq!(f.sample_clamped(0.0), 0.0);
assert_eq!(f.sample_clamped(0.5), 0.5);
assert_eq!(f.sample_clamped(1.0), 1.0);
assert_eq!(f.sample_clamped(2.0), 1.0);

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Linear

f(t) = t

QuadraticIn

f(t) = t²

This is the Hermite interpolator for

• f(0) = 0
• f(1) = 1
• f′(0) = 0

QuadraticOut

f(t) = -(t * (t - 2.0))

This is the Hermite interpolator for

• f(0) = 0
• f(1) = 1
• f′(1) = 0

QuadraticInOut

Behaves as EaseFunction::QuadraticIn for t < 0.5 and as EaseFunction::QuadraticOut for t >= 0.5

A quadratic has too low of a degree to be both an InOut and C², so consider using at least a cubic (such as EaseFunction::SmoothStep) if you want the acceleration to be continuous.

CubicIn

f(t) = t³

This is the Hermite interpolator for

• f(0) = 0
• f(1) = 1
• f′(0) = 0
• f″(0) = 0

CubicOut

f(t) = (t - 1.0)³ + 1.0

CubicInOut

Behaves as EaseFunction::CubicIn for t < 0.5 and as EaseFunction::CubicOut for t >= 0.5

Due to this piecewise definition, this is only C¹ despite being a cubic: the acceleration jumps from +12 to -12 at t = ½.

Consider using EaseFunction::SmoothStep instead, which is also cubic, or EaseFunction::SmootherStep if you picked this because you wanted the acceleration at the endpoints to also be zero.

QuarticIn

f(t) = t⁴

QuarticOut

f(t) = (t - 1.0)³ * (1.0 - t) + 1.0

QuarticInOut

Behaves as EaseFunction::QuarticIn for t < 0.5 and as EaseFunction::QuarticOut for t >= 0.5

QuinticIn

f(t) = t⁵

QuinticOut

f(t) = (t - 1.0)⁵ + 1.0

QuinticInOut

Behaves as EaseFunction::QuinticIn for t < 0.5 and as EaseFunction::QuinticOut for t >= 0.5

Due to this piecewise definition, this is only C¹ despite being a quintic: the acceleration jumps from +40 to -40 at t = ½.

Consider using EaseFunction::SmootherStep instead, which is also quintic.

SmoothStepIn

Behaves as the first half of EaseFunction::SmoothStep.

This has f″(1) = 0, unlike EaseFunction::QuadraticIn which starts similarly.

SmoothStepOut

Behaves as the second half of EaseFunction::SmoothStep.

This has f″(0) = 0, unlike EaseFunction::QuadraticOut which ends similarly.

SmoothStep

f(t) = 2t³ + 3t²

This is the Hermite interpolator for

• f(0) = 0
• f(1) = 1
• f′(0) = 0
• f′(1) = 0

See also smoothstep in GLSL.

SmootherStepIn

Behaves as the first half of EaseFunction::SmootherStep.

This has f″(1) = 0, unlike EaseFunction::CubicIn which starts similarly.

SmootherStepOut

Behaves as the second half of EaseFunction::SmootherStep.

This has f″(0) = 0, unlike EaseFunction::CubicOut which ends similarly.

SmootherStep

f(t) = 6t⁵ - 15t⁴ + 10t³

This is the Hermite interpolator for

• f(0) = 0
• f(1) = 1
• f′(0) = 0
• f′(1) = 0
• f″(0) = 0
• f″(1) = 0

SineIn

f(t) = 1.0 - cos(t * π / 2.0)

SineOut

f(t) = sin(t * π / 2.0)

SineInOut

Behaves as EaseFunction::SineIn for t < 0.5 and as EaseFunction::SineOut for t >= 0.5

CircularIn

f(t) = 1.0 - sqrt(1.0 - t²)

CircularOut

f(t) = sqrt((2.0 - t) * t)

CircularInOut

Behaves as EaseFunction::CircularIn for t < 0.5 and as EaseFunction::CircularOut for t >= 0.5

ExponentialIn

f(t) ≈ 2.0^(10.0 * (t - 1.0))

The precise definition adjusts it slightly so it hits both (0, 0) and (1, 1): f(t) = 2.0^(10.0 * t - A) - B, where A = log₂(2¹⁰-1) and B = 1/(2¹⁰-1).

ExponentialOut

f(t) ≈ 1.0 - 2.0^(-10.0 * t)

As with EaseFunction::ExponentialIn, the precise definition adjusts it slightly

ExponentialInOut

Behaves as EaseFunction::ExponentialIn for t < 0.5 and as EaseFunction::ExponentialOut for t >= 0.5

ElasticIn

f(t) = -2.0^(10.0 * t - 10.0) * sin((t * 10.0 - 10.75) * 2.0 * π / 3.0)

ElasticOut

f(t) = 2.0^(-10.0 * t) * sin((t * 10.0 - 0.75) * 2.0 * π / 3.0) + 1.0

ElasticInOut

Behaves as EaseFunction::ElasticIn for t < 0.5 and as EaseFunction::ElasticOut for t >= 0.5

BackIn

f(t) = 2.70158 * t³ - 1.70158 * t²

BackOut

f(t) = 1.0 + 2.70158 * (t - 1.0)³ - 1.70158 * (t - 1.0)²

BackInOut

Behaves as EaseFunction::BackIn for t < 0.5 and as EaseFunction::BackOut for t >= 0.5

BounceIn

bouncy at the start!

BounceOut

bouncy at the end!

BounceInOut

Behaves as EaseFunction::BounceIn for t < 0.5 and as EaseFunction::BounceOut for t >= 0.5

Steps(usize, JumpAt)

n steps connecting the start and the end. Jumping behavior is customizable via JumpAt. See JumpAt for all the options and visual examples.

Elastic(f32)

f(omega,t) = 1 - (1 - t)²(2sin(omega * t) / omega + cos(omega * t)), parametrized by omega

Trait Implementations

impl Clone for EaseFunction

fn clone(&self) -> EaseFunction

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Curve<f32> for EaseFunction

fn domain(&self) -> Interval

The interval over which this curve is parametrized.

fn sample_unchecked(&self, t: f32) -> f32

Sample a point on this curve at the parameter value t, extracting the associated value. This is the unchecked version of sampling, which should only be used if the sample time t is already known to lie within the curve’s domain.

fn sample(&self, t: f32) -> Option<T>

Sample a point on this curve at the parameter value t, returning None if the point is outside of the curve’s domain.

fn sample_clamped(&self, t: f32) -> T

Sample a point on this curve at the parameter value t, clamping t to lie inside the domain of the curve.

impl Debug for EaseFunction

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for EaseFunction

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Enum for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn field(&self, __name_param: &str) -> Option<&dyn PartialReflect>

Returns a reference to the value of the field (in the current variant) with the given name.

fn field_at(&self, __index_param: usize) -> Option<&dyn PartialReflect>

Returns a reference to the value of the field (in the current variant) at the given index.

fn field_mut(&mut self, __name_param: &str) -> Option<&mut dyn PartialReflect>

Returns a mutable reference to the value of the field (in the current variant) with the given name.

fn field_at_mut( &mut self, __index_param: usize, ) -> Option<&mut dyn PartialReflect>

Returns a mutable reference to the value of the field (in the current variant) at the given index.

fn index_of(&self, __name_param: &str) -> Option<usize>

Returns the index of the field (in the current variant) with the given name.

fn name_at(&self, __index_param: usize) -> Option<&str>

Returns the name of the field (in the current variant) with the given index.

fn iter_fields(&self) -> VariantFieldIter<'_>

Returns an iterator over the values of the current variant’s fields.

fn field_len(&self) -> usize

Returns the number of fields in the current variant.

fn variant_name(&self) -> &str

The name of the current variant.

fn variant_index(&self) -> usize

The index of the current variant.

fn variant_type(&self) -> VariantType

The type of the current variant.

fn to_dynamic_enum(&self) -> DynamicEnum

Creates a new DynamicEnum from this enum.

fn clone_dynamic(&self) -> DynamicEnum

👎Deprecated since 0.16.0: use to_dynamic_enum instead

fn is_variant(&self, variant_type: VariantType) -> bool

Returns true if the current variant’s type matches the given one.

fn variant_path(&self) -> String

Returns the full path to the current variant.

fn get_represented_enum_info(&self) -> Option<&'static EnumInfo>

Will return None if TypeInfo is not available.

impl FromReflect for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn from_reflect(__param0: &dyn PartialReflect) -> Option<Self>

Constructs a concrete instance of Self from a reflected value.

fn take_from_reflect( reflect: Box<dyn PartialReflect>, ) -> Result<Self, Box<dyn PartialReflect>>

Attempts to downcast the given value to Self using, constructing the value using from_reflect if that fails.

impl GetTypeRegistration for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn get_type_registration() -> TypeRegistration

Returns the default TypeRegistration for this type.

fn register_type_dependencies(registry: &mut TypeRegistry)

Registers other types needed by this type.

impl PartialEq for EaseFunction

fn eq(&self, other: &EaseFunction) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialReflect for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn get_represented_type_info(&self) -> Option<&'static TypeInfo>

Returns the TypeInfo of the type represented by this value.

fn try_apply( &mut self, __value_param: &dyn PartialReflect, ) -> Result<(), ApplyError>

Tries to apply a reflected value to this value.

fn reflect_kind(&self) -> ReflectKind

Returns a zero-sized enumeration of “kinds” of type.

fn reflect_ref(&self) -> ReflectRef<'_>

Returns an immutable enumeration of “kinds” of type.

fn reflect_mut(&mut self) -> ReflectMut<'_>

Returns a mutable enumeration of “kinds” of type.

fn reflect_owned(self: Box<Self>) -> ReflectOwned

Returns an owned enumeration of “kinds” of type.

fn try_into_reflect( self: Box<Self>, ) -> Result<Box<dyn Reflect>, Box<dyn PartialReflect>>

Attempts to cast this type to a boxed, fully-reflected value.

fn try_as_reflect(&self) -> Option<&dyn Reflect>

Attempts to cast this type to a fully-reflected value.

fn try_as_reflect_mut(&mut self) -> Option<&mut dyn Reflect>

Attempts to cast this type to a mutable, fully-reflected value.

fn into_partial_reflect(self: Box<Self>) -> Box<dyn PartialReflect>

Casts this type to a boxed, reflected value.

fn as_partial_reflect(&self) -> &dyn PartialReflect

Casts this type to a reflected value.

fn as_partial_reflect_mut(&mut self) -> &mut dyn PartialReflect

Casts this type to a mutable, reflected value.

fn reflect_hash(&self) -> Option<u64>

Returns a hash of the value (which includes the type).

fn reflect_partial_eq(&self, value: &dyn PartialReflect) -> Option<bool>

Returns a “partial equality” comparison result.

fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError>

Attempts to clone Self using reflection.

fn apply(&mut self, value: &(dyn PartialReflect + 'static))

Applies a reflected value to this value.

fn clone_value(&self) -> Box<dyn PartialReflect>

👎Deprecated since 0.16.0: to clone reflected values, prefer using reflect_clone. To convert reflected values to dynamic ones, use to_dynamic.

Clones Self into its dynamic representation.

fn to_dynamic(&self) -> Box<dyn PartialReflect>

Converts this reflected value into its dynamic representation based on its kind.

fn debug(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Debug formatter for the value.

fn is_dynamic(&self) -> bool

Indicates whether or not this type is a dynamic type.

impl Reflect for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn into_any(self: Box<Self>) -> Box<dyn Any>

Returns the value as a Box<dyn Any>.

fn as_any(&self) -> &dyn Any

Returns the value as a &dyn Any.

fn as_any_mut(&mut self) -> &mut dyn Any

Returns the value as a &mut dyn Any.

fn into_reflect(self: Box<Self>) -> Box<dyn Reflect>

Casts this type to a boxed, fully-reflected value.

fn as_reflect(&self) -> &dyn Reflect

Casts this type to a fully-reflected value.

fn as_reflect_mut(&mut self) -> &mut dyn Reflect

Casts this type to a mutable, fully-reflected value.

fn set(&mut self, value: Box<dyn Reflect>) -> Result<(), Box<dyn Reflect>>

Performs a type-checked assignment of a reflected value to this value.

impl Serialize for EaseFunction

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl TypePath for EaseFunction

where EaseFunction: Any + Send + Sync,

fn type_path() -> &'static str

Returns the fully qualified path of the underlying type.

fn short_type_path() -> &'static str

Returns a short, pretty-print enabled path to the type.

fn type_ident() -> Option<&'static str>

Returns the name of the type, or None if it is anonymous.

fn crate_name() -> Option<&'static str>

Returns the name of the crate the type is in, or None if it is anonymous.

fn module_path() -> Option<&'static str>

Returns the path to the module the type is in, or None if it is anonymous.

impl Typed for EaseFunction

where EaseFunction: Any + Send + Sync, usize: FromReflect + TypePath + MaybeTyped + RegisterForReflection, JumpAt: FromReflect + TypePath + MaybeTyped + RegisterForReflection, f32: FromReflect + TypePath + MaybeTyped + RegisterForReflection,

fn type_info() -> &'static TypeInfo

Returns the compile-time info for the underlying type.

impl Copy for EaseFunction

impl StructuralPartialEq for EaseFunction