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use super::*;
/// Produce a shape that approximates an axis-aligned ellipse.
pub fn ellipse(size: Size, fill: Option<Paint>, stroke: Option<Stroke>) -> Shape {
// https://stackoverflow.com/a/2007782
let z = Abs::zero();
let rx = size.x / 2.0;
let ry = size.y / 2.0;
let m = 0.551784;
let mx = m * rx;
let my = m * ry;
let point = |x, y| Point::new(x + rx, y + ry);
let mut path = Path::new();
path.move_to(point(-rx, z));
path.cubic_to(point(-rx, -my), point(-mx, -ry), point(z, -ry));
path.cubic_to(point(mx, -ry), point(rx, -my), point(rx, z));
path.cubic_to(point(rx, my), point(mx, ry), point(z, ry));
path.cubic_to(point(-mx, ry), point(-rx, my), point(-rx, z));
Shape { geometry: Geometry::Path(path), stroke, fill }
}
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