Struct ArcGeometry 

pub struct ArcGeometry {
    pub center: Point,
    pub inner_radius: f32,
    pub outer_radius: f32,
    pub start_angle: f32,
    pub sweep_angle: f32,
    pub cap: StrokeCap,
}

A resolved circular band between two radii, limited to an angular sweep.

Both a stroked arc and a filled annular sector lower to this single form:

• stroked arc — inner = radius - width/2, outer = radius + width/2, ends shaped by the stroke’s StrokeCap;
• filled annular sector — inner/outer as given, always butt (flat radial) ends.

Values are normalized on construction: sweep_angle is non-negative and at most TAU, outer_radius >= inner_radius >= 0, and non-finite inputs collapse to a degenerate geometry (see ArcGeometry::is_degenerate).

Fields

center: Point

inner_radius: f32

outer_radius: f32

start_angle: f32

Normalized to [0, TAU).

sweep_angle: f32

Normalized to [0, TAU].

cap: StrokeCap

Implementations

impl ArcGeometry

pub fn new( center: Point, inner_radius: f32, outer_radius: f32, start_angle: f32, sweep_angle: f32, cap: StrokeCap, ) -> Self

Normalizing constructor. Never panics and never stores a NaN.

pub fn mid_radius(&self) -> f32

Radius of the band’s centerline (ra in the analytic arc SDF).

pub fn half_thickness(&self) -> f32

Half the band thickness (rb in the analytic arc SDF). Also the radius of a round cap and the projection distance of a square cap.

pub fn is_degenerate(&self) -> bool

True when the band encloses no area and therefore must not be emitted.

pub fn contains_angle(&self, angle: f32) -> bool

True when angle lies inside [start, start + sweep] (mod TAU).

pub fn scaled_about(&self, center: Point, scale: f32) -> Self

Scales radii and translates the center. Angles are unchanged, so this is only valid for a uniform (non-mirroring) scale.

pub fn bounds(&self) -> Rect

Tight axis-aligned bounding box of the rendered band, caps included.

The box is the union of

• the two radial ends (inner and outer radius, extended for round/square caps), and
• the outer-radius point at every axis direction (0, 90, 180, 270 degrees) that the sweep actually crosses.

Sampling only the endpoints would be wrong for any sweep that crosses an axis: a 0..270 degree sweep reaches center.x + outer and center.x - outer even though neither endpoint does.

Trait Implementations

impl Clone for ArcGeometry

fn clone(&self) -> ArcGeometry

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ArcGeometry

impl Debug for ArcGeometry

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

Formats the value using the given formatter.

impl PartialEq for ArcGeometry

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ArcGeometry