Struct DrawExtent 

pub struct DrawExtent {
    pub total_len: f32,
    pub in_frame_len: f32,
}

How much of the drawn segment length landed inside the render target, summed over one LineRenderer::draw call (Plan 0069, ADR-0083).

Pixel coverage cannot see an over-scaled figure: a comb roots every bar on a shared baseline and a corona roots every spoke at a centre, so clipping the tips costs a rounding error of lit pixels and the statistic goes the wrong way. Length does see it — a bar that overshoots loses in-frame length in exact proportion to the overshoot.

Length, not area. The stroke’s width and the ADR-0041 join extensions are not counted, so a thick stroke leaving the frame is under-counted. That is the right measure for overshoot and a poor one for anything else.

Arcs count too (Plan 0087 Phase 2). An ArcInstance contributes its own arc length, |sweep| * radius, to both sums. This is a correctness obligation of the arc primitive rather than a feature: an arc contributing nothing would shrink the denominator, and every arc-drawing preset would read better-framed than it is — the more so as the primitive replaces whole motifs, where the missing length is most of the figure.

Fields

total_len: f32

World-space length of every segment actually drawn (post view transform).

in_frame_len: f32

The share of that length lying inside [-aspect, aspect] x [-1, 1].

Implementations

impl DrawExtent

pub fn fraction(self) -> Option<f32>

The in-frame fraction — exactly 1.0 when nothing was clipped, exactly 0.0 when the whole figure is outside.

None when nothing was drawn at all: that is a 0/0, and inventing a number for it is what made Plan 0058’s table print inf. “Nothing drawn” is the total case and core/tests/sanity.rs is its instrument, not this one.

Trait Implementations

impl Clone for DrawExtent

fn clone(&self) -> DrawExtent

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DrawExtent

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

Formats the value using the given formatter.

impl Default for DrawExtent

fn default() -> DrawExtent

Returns the “default value” for a type.

impl PartialEq for DrawExtent

fn eq(&self, other: &DrawExtent) -> 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 Copy for DrawExtent

impl StructuralPartialEq for DrawExtent