use references to hittables for hittablelist

Author: Jeremy5909

src/hittable.rs

@@ -9,15 +9,6 @@ pub struct HitRecord {
 	pub front_face: bool,
 }
 impl HitRecord {
-	// pub fn new() -> Self {
-	// 	HitRecord{
-	// 		p: Point3::new(0.0, 0.0, 0.0),
-	// 		normal: Vec3::new(0.0, 0.0, 0.0),
-	// 		t: 0.0,
-	// 		front_face: false,
-	// 		mat: None,
-	// 	}
-	// }
 	pub fn set_face_normal(&mut self, r: &Ray, outward_normal: &Vec3) {
 		self.front_face = dot(*r.dir(), *outward_normal) < 0.0;
 		self.normal = if self.front_face {*outward_normal} else {-*outward_normal}

src/hittable_list.rs

@@ -1,17 +1,17 @@
 use crate::{hittable::{HitRecord, Hittable}, interval::Interval};
 
-pub struct HittableList {
-	objects: Vec<Box<dyn Hittable>>,
+pub struct HittableList<'a> {
+	objects: Vec<&'a dyn Hittable>,
 }
-impl HittableList {
+impl<'a> HittableList<'a> {
 	pub fn new() -> Self {
 		HittableList{objects: Vec::new()}
 	}
-	pub fn add(&mut self, object: Box<dyn Hittable>) {
+	pub fn add(&mut self, object: &'a dyn Hittable) {
 		self.objects.push(object);
 	}
 }
-impl Hittable for HittableList {
+impl<'a> Hittable for HittableList<'a> {
 	fn hit(&self, r: &crate::ray::Ray, ray_t: Interval, rec: &mut HitRecord) -> bool {
 		let mut temp_rec = HitRecord::default();
 		let mut hit_anything = false;

src/main.rs

@@ -27,10 +27,10 @@ fn main() {
     let left = Sphere::new(Point3::new(-1.0, 0.0, -1.0), 0.5, Box::new(left));
     let right = Sphere::new(Point3::new(1.0, 0.0, -1.0), 0.5, Box::new(right));
 
-    world.add(Box::new(ground));
-    world.add(Box::new(center));
-    world.add(Box::new(left));
-    world.add(Box::new(right));
+    world.add(&ground);
+    world.add(&center);
+    world.add(&left);
+    world.add(&right);
 
     let mut cam = Camera::new(16.0/9.0, 400);
     cam.samples_per_pixel = 100;