competitive/geometry/
circle.rs

1use super::{Approx, Ccwable, Complex, Float};
2
3#[derive(Clone, Debug, PartialEq)]
4pub struct Circle<T> {
5    c: Complex<T>,
6    r: T,
7}
8impl<T> Circle<T>
9where
10    T: Ccwable + Float,
11{
12    pub fn new(c: Complex<T>, r: T) -> Self {
13        Circle { c, r }
14    }
15    pub fn cross_circle(&self, other: &Self) -> Option<(Complex<T>, Complex<T>)> {
16        let d = (self.c - other.c).abs();
17        let rc = (d * d + self.r * self.r - other.r * other.r) / (d + d);
18        let rs2 = self.r * self.r - rc * rc;
19        if Approx(rs2) < Approx(T::zero()) {
20            return None;
21        }
22        let rs = rs2.abs().sqrt();
23        let diff = (other.c - self.c) / d;
24        Some((
25            self.c + diff * Complex::new(rc, rs),
26            self.c + diff * Complex::new(rc, -rs),
27        ))
28    }
29    pub fn contains_point(&self, p: Complex<T>) -> bool {
30        Approx((self.c - p).abs()) <= Approx(self.r)
31    }
32}
competitive/geometry/circle.rs

competitive/geometry/
circle.rs
