Struct ColorMatrix 

pub struct ColorMatrix {
    pub matrix: [[f32; 5]; 4],
}

A 4×5 colour transformation matrix.

Each output channel is:

out_R = m[0][0]*R + m[0][1]*G + m[0][2]*B + m[0][3]*A + m[0][4]
out_G = m[1][0]*R + m[1][1]*G + m[1][2]*B + m[1][3]*A + m[1][4]
out_B = m[2][0]*R + m[2][1]*G + m[2][2]*B + m[2][3]*A + m[2][4]
out_A = m[3][0]*R + m[3][1]*G + m[3][2]*B + m[3][3]*A + m[3][4]

Fields

matrix: [[f32; 5]; 4]

Row-major 4×5 matrix: rows are [R, G, B, A] output channels.

Implementations

impl ColorMatrix

pub fn identity() -> Self

Identity matrix — no change to colours.

pub fn brightness(factor: f32) -> Self

Scale all RGB channels by factor. Alpha is unchanged.

pub fn contrast(factor: f32) -> Self

Contrast adjustment around the midpoint 0.5.

A factor of 1.0 is a no-op; values above 1.0 increase contrast.

pub fn saturation(factor: f32) -> Self

Saturation adjustment.

Uses ITU-R BT.601 luma weights. factor = 0 → greyscale, factor = 1 → no change, factor > 1 → more saturated.

pub fn hue_rotate(degrees: f32) -> Self

Hue rotation by degrees.

Implemented as a rotation in the colour-opponent plane after projecting out the luminance axis (Hacker-level approximation suitable for real-time use).

pub fn invert() -> Self

Invert all RGB channels (1.0 - channel). Alpha is unchanged.

pub fn grayscale() -> Self

Greyscale conversion using ITU-R BT.601 luma weights.

pub fn sepia() -> Self

Sepia-tone matrix (classic film emulation).

pub fn apply(&self, pixel: Rgba) -> Rgba

Apply the matrix to a single pixel, clamping the result to [0, 1].

pub fn compose(&self, other: &ColorMatrix) -> ColorMatrix

Compose two matrices: self ∘ other (apply other first, then self).

The 4×5 matrices are augmented to 5×5 (with an implicit row [0,0,0,0,1]) for standard homogeneous composition, then the result is trimmed back to 4×5.

Trait Implementations

impl Clone for ColorMatrix

fn clone(&self) -> ColorMatrix

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ColorMatrix

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

Formats the value using the given formatter.

impl Copy for ColorMatrix