parry2d/transformation/to_polyline/
round_convex_polygon_to_polyline.rs

1use crate::math::Vector2;
2use crate::shape::RoundConvexPolygon;
3use crate::transformation::utils;
4use alloc::{vec, vec::Vec};
5
6impl RoundConvexPolygon {
7    /// Discretize the boundary of this round convex polygon as a polygonal line.
8    pub fn to_polyline(&self, border_subdivs: u32) -> Vec<Vector2> {
9        let mut out_vtx = vec![];
10        let pts = self.inner_shape.points();
11        let ns = self.inner_shape.normals();
12        let br = self.border_radius;
13
14        out_vtx.push(pts[0] + *ns.last().unwrap() * br);
15
16        for ia in 0..pts.len() - 1 {
17            let ib = ia + 1;
18
19            let arc_start = *out_vtx.last().unwrap();
20            let arc_end = pts[ia] + ns[ia] * br;
21            utils::push_arc(pts[ia], arc_start, arc_end, border_subdivs, &mut out_vtx);
22            out_vtx.push(arc_end);
23            out_vtx.push(pts[ib] + ns[ia] * br);
24        }
25
26        let arc_center = *pts.last().unwrap();
27        let arc_start = *out_vtx.last().unwrap();
28        let arc_end = arc_center + *ns.last().unwrap() * br;
29        utils::push_arc(arc_center, arc_start, arc_end, border_subdivs, &mut out_vtx);
30        out_vtx.push(arc_end);
31
32        out_vtx
33    }
34}