extern crate cgmath;
use cgmath::*;
use std::num::Float;
#[test]
fn test_intersection() {
let sphere = Sphere {center: Point3::new(0f64,0f64,0f64), radius: 1f64};
let r0 = Ray::new(Point3::new(0f64, 0f64, 5f64), Vector3::new(0f64, 0f64, -5f64).normalize());
let r1 = Ray::new(Point3::new(1f64.cos(), 0f64, 5f64), Vector3::new(0f64, 0f64, -5f64).normalize());
let r2 = Ray::new(Point3::new(1f64, 0f64, 5f64), Vector3::new(0f64, 0f64, -5f64).normalize());
let r3 = Ray::new(Point3::new(2f64, 0f64, 5f64), Vector3::new(0f64, 0f64, -5f64).normalize());
assert_eq!((sphere,r0).intersection(), Some(Point3::new(0f64, 0f64, 1f64)));
assert!((sphere,r1).intersection().unwrap().approx_eq( &Point3::new(1f64.cos(), 0f64, 1f64.sin()) ));
assert_eq!((sphere,r2).intersection(), Some(Point3::new(1f64, 0f64, 0f64)));
assert_eq!((sphere,r3).intersection(), None);
}