Enum ShadingGradient 

pub enum ShadingGradient {
    Axial {
        coords: [f32; 4],
        extend: [bool; 2],
        stops: Vec<Rgba>,
    },
    Radial {
        coords: [f32; 6],
        extend: [bool; 2],
        stops: Vec<Rgba>,
    },
    FunctionBased {
        domain: [f32; 4],
        matrix: Transform2D,
        grid: (usize, usize),
        samples: Vec<Rgba>,
    },
}

Evaluated geometry + sampled colour for a Type 1–3 shading (§8.7.4.5.2–4). The colour function is sampled at a fixed resolution so a downstream rasteriser sees concrete RGB stops rather than an abstract function object; the geometry (axis / circles / domain rectangle) and Extend flags are carried so the consumer can map a device-space point to its parametric value.

Variants

Axial

Type 2 (axial) shading (§8.7.4.5.3): a colour blend along the linear axis from (x0, y0) to (x1, y1).

Fields

coords: [f32; 4]

Axis endpoints [x0, y0, x1, y1] (Coords) in target space.

extend: [bool; 2]

Extend flags [before, after] (§8.7.4.5.3).

stops: Vec<Rgba>

Colour stops sampled uniformly across the Domain [t0, t1], from t0 (first) to t1 (last).

Radial

Type 3 (radial) shading (§8.7.4.5.4): a colour blend between the circle (x0, y0, r0) and (x1, y1, r1).

Fields

coords: [f32; 6]

Circle parameters [x0, y0, r0, x1, y1, r1] (Coords).

extend: [bool; 2]

Extend flags [before, after] (§8.7.4.5.4).

stops: Vec<Rgba>

Colour stops sampled uniformly across the Domain [t0, t1], from the starting circle (s = 0) to the ending circle (s = 1).

FunctionBased

Type 1 (function-based) shading (§8.7.4.5.2): the colour at every point of the Domain rectangle is the value of a 2-in / n-out function. Sampled onto a uniform grid over the domain.

Fields

domain: [f32; 4]

Domain rectangle [xmin, xmax, ymin, ymax] (Domain).

matrix: Transform2D

Matrix mapping the domain rectangle into target space.

grid: (usize, usize)

Grid width / height (samples per axis).

samples: Vec<Rgba>

grid.0 × grid.1 sampled colours, row-major with the first (x) axis varying fastest; sample (i, j) at index j * grid.0 + i corresponds to domain point (xmin + i·dx, ymin + j·dy).

Trait Implementations

impl Clone for ShadingGradient

fn clone(&self) -> ShadingGradient

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ShadingGradient

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

Formats the value using the given formatter.

impl PartialEq for ShadingGradient

fn eq(&self, other: &ShadingGradient) -> 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 StructuralPartialEq for ShadingGradient