ft: 5,6.1: sphere class + normals

src/main.rs

@@ -1,16 +1,40 @@
 #![feature(core_float_math)]
 
+mod objects;
 mod ray;
 mod vec3;
 
+use core::f32;
 use std::cmp::max;
 
+use crate::objects::hit::Hit;
+use crate::objects::sphere::Sphere;
+use crate::objects::traits::{Hittable, Normal};
 use crate::ray::Ray;
 use crate::vec3::{Colour, Vec3};
 use log::info;
 use pretty_env_logger;
 
-fn ray_colour(r: &Ray) -> Colour {
+fn ray_colour<T>(hittables: &Vec<T>, r: &Ray) -> Colour
+where
+    T: Hittable + Normal,
+{
+    let mut closest: Option<Hit> = None;
+    for hittable in hittables {
+        if let Some(hit) = hittable.hit(r) {
+            // hit happens in front of camera and is closer than closest
+            if *hit.t() > 0. && (closest.is_none() || closest.as_ref().unwrap().t() > hit.t()) {
+                closest = Some(hit);
+            }
+        }
+    }
+
+    if let Some(hit) = closest {
+        let n = hit.n();
+        return 0.5 * Colour::new(n.x() + 1., n.y() + 1., n.z() + 1.);
+    }
+
+    // background
     let unit_dir = r.dir().get_unit();
     let a = 0.5 * (unit_dir.y() + 1.);
 
@@ -19,8 +43,8 @@ fn ray_colour(r: &Ray) -> Colour {
 
 fn main() {
     // use structs so rust-analyzer can provide lsp
-    let v = Vec3::new(255., 0., 255.);
-    let _ = Ray::new(v.clone(), v.clone());
+    let s = Sphere::new(Vec3::new(0., 0., -1.), 0.5);
+    let objects = vec![s];
 
     pretty_env_logger::init();
 
@@ -56,7 +80,7 @@ fn main() {
             let r = Ray::new(camera_center, ray_dir);
 
             let pixel = imgbuf.get_pixel_mut(i, j);
-            *pixel = ray_colour(&r).output();
+            *pixel = ray_colour(&objects, &r).output();
         }
     }