use std::fmt::Debug;

#[derive(Debug)]
struct Sphere ();

#[derive(Debug)]
struct Cube {
    size: f32,
}

#[derive(Debug)]
struct Intersection<'a> {
    t: f32,
    obj: &'a Shape
}

#[derive(Debug)]
struct Intersections<'a> (Vec<Intersection<'a>>);


trait Shape: Debug {
    fn intersects(&self, ray: f32) -> Intersections;
}

impl Shape for Sphere {
    fn intersects(&self, ray: f32) -> Intersections {
        return Intersections(vec![Intersection{
            t: ray,
            obj: self
        }])
    }
}

impl Shape for Cube {
    fn intersects(&self, ray: f32) -> Intersections {
        return Intersections(vec![Intersection{
            t: ray,
            obj: self
        }])
    }
}

fn main() {
    let mut v = Sphere().intersects(2.).0;
    v.append( & mut Cube {size: 1.}.intersects(3.).0);
    println!("{:?}", Intersections(v));
}