pub fn hatch(
outline: &[Vec<Point2>],
spacing: f64,
angle: f64,
) -> Vec<(Point2, Point2)>Expand description
Hatch the section outline: parallel lines at angle, spacing apart,
clipped to the material by the even-odd rule.
The outline loops are taken as SectionView::outline hands them over
(outer loops and holes together), so a hole interrupts the hatching
exactly as it interrupts the material. Each returned pair is one hatch
stroke in the plane’s (x, y).