Pythagoras tree: Difference between revisions

let rg = |step| lvl.wrapping_mul(step).wrapping_add(80 - step * 2);

let g = Group::new().set("fill", format!("#{:02X}{:02X}18", rg(20), rg(30))); // level color

let v = (b.0 - a.0, b.1 - a.1);

let [c, d, w] = [a, b, v].map(|p| (p.0 + v.1, p.1 - v.0));