Struct ScalarEncoding 

pub struct ScalarEncoding {
    pub power: u8,
    pub root: u8,
    pub scale_bits: u32,
}

How a scalar is stored in the lanes of an output: stored = (value / scale)^(root / power), so the value is stored^(power / root) * scale (the scale given by its f32 bits). Power and root 1 are linear; power 2 a square root stored (a value kept in a perceptual range), 4 a fourth root; root 2 a square stored (a value the lighting takes the square root of).

Fields

power: u8

The power the stored value is raised to, to give the value over the scale: 1 for none, 2 for the square root stored, 4 for the fourth root. Never 0.

root: u8

The root taken of the stored value raised to power: 1 for none, 2 for the square stored. Never 0.

scale_bits: u32

The scale’s f32 bits (1.0 for none): bits so the encoding compares and hashes exactly; it is written as the number scale.

Implementations

impl ScalarEncoding

pub const LINEAR: Self

The value as it is (scale 1).

pub fn linear_over(scale: f32) -> Self

Stored as the value over scale, no power.

pub fn square_root_of(scale: f32) -> Self

Stored as the square root of the value over scale.

pub fn power_of(power: u8, scale: f32) -> Self

Stored as the powerth root of the value over scale (power 0 is taken as 1: no power).

pub fn square_of(scale: f32) -> Self

Stored as the square of the value over scale: the value is the stored one’s square root times scale.

pub fn decode(&self, stored: f32) -> f32

The value for a stored one (a root of a negative stored value is taken of 0).

impl ScalarEncoding

pub fn check(&self) -> Result<(), String>

Whether the encoding is one: a power and a root other than 0, and a finite scale.

Trait Implementations

impl Clone for ScalarEncoding

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ScalarEncoding

impl Debug for ScalarEncoding

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

Formats the value using the given formatter.

impl Eq for ScalarEncoding

impl Hash for ScalarEncoding

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for ScalarEncoding

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for ScalarEncoding

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ScalarEncoding