pub fn offset_edge(
p0: (f64, f64),
p1: (f64, f64),
distance: f64,
) -> ((f64, f64), (f64, f64))Expand description
Offsets a single directed edge segment by translating along its outward normal.
For a CCW-wound polygon, the outward normal of edge (p0 -> p1) points to
the right: (dy, -dx) normalized, then scaled by distance.