From 0fb53807c636872887a71d11c8ee009be42dc502 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tomasz=20K=C5=82ak?= <ext-lux-tk@ad.datcon.co.uk>
Date: Sun, 21 Feb 2021 12:14:23 +0100
Subject: [PATCH] ch 11 done

---
 src/camera.rs        | 26 ++++++++++++++------------
 src/hittable_list.rs |  4 ----
 src/main.rs          | 25 ++++++++++---------------
 src/material.rs      |  4 ++--
 4 files changed, 26 insertions(+), 33 deletions(-)

diff --git a/src/camera.rs b/src/camera.rs
index 397eaee..4b0db79 100644
--- a/src/camera.rs
+++ b/src/camera.rs
@@ -1,4 +1,4 @@
-use crate::{Point3, Ray, Vec3};
+use crate::{cross, degrees_to_radians, unit_vector, Point3, Ray, Vec3};
 
 pub struct Camera {
     origin: Point3,
@@ -8,17 +8,19 @@ pub struct Camera {
 }
 
 impl Camera {
-    pub fn new() -> Self {
-        let aspect_ratio = 16.0 / 9.0;
-        let viewport_height = 2.0;
+    pub fn new(lookfrom: Point3, lookat: Point3, vup: Vec3, vfov: f64, aspect_ratio: f64) -> Self {
+        let theta = degrees_to_radians(vfov);
+        let h = (theta / 2.0).tan();
+        let viewport_height = 2.0 * h;
         let viewport_width = aspect_ratio * viewport_height;
-        let focal_length = 1.0;
 
-        let origin = Point3::new(0., 0., 0.);
-        let horizontal = Vec3::new(viewport_width, 0.0, 0.0);
-        let vertical = Vec3::new(0.0, viewport_height, 0.0);
-        let lower_left_corner =
-            origin - horizontal / 2. - vertical / 2. - Vec3::new(0., 0., focal_length);
+        let w = unit_vector(lookfrom - lookat);
+        let u = unit_vector(cross(&vup, &w));
+        let v = cross(&w, &u);
+        let origin = lookfrom;
+        let horizontal = viewport_width * u;
+        let vertical = viewport_height * v;
+        let lower_left_corner = origin - horizontal / 2. - vertical / 2. - w;
         Self {
             origin,
             lower_left_corner,
@@ -27,10 +29,10 @@ impl Camera {
         }
     }
 
-    pub fn get_ray(&self, u: f64, v: f64) -> Ray {
+    pub fn get_ray(&self, s: f64, t: f64) -> Ray {
         return Ray::new(
             &self.origin,
-            &(self.lower_left_corner + u * self.horizontal + v * self.vertical - self.origin),
+            &(self.lower_left_corner + s * &self.horizontal + t * self.vertical - self.origin),
         );
     }
 }
diff --git a/src/hittable_list.rs b/src/hittable_list.rs
index d2e8d18..3f56661 100644
--- a/src/hittable_list.rs
+++ b/src/hittable_list.rs
@@ -12,10 +12,6 @@ impl HittableList {
         HittableList { objects: vec![] }
     }
 
-    pub fn clear(&mut self) {
-        self.objects.clear();
-    }
-
     pub fn add(&mut self, object: Arc<dyn Hittable>) {
         self.objects.push(object);
     }
diff --git a/src/main.rs b/src/main.rs
index 2a17317..2d8f0e6 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -24,19 +24,7 @@ use camera::*;
 mod material;
 use material::*;
 
-fn hit_sphere(center: &Point3, radius: f64, r: &Ray) -> f64 {
-    let oc = r.origin() - *center;
-    let a = r.direction().length_squared();
-    let half_b = dot(&oc, &r.direction());
-    let c = oc.length_squared() - radius * radius;
-    let discriminant = half_b * half_b - a * c;
-
-    if discriminant < 0.0 {
-        -1.0
-    } else {
-        (-half_b - discriminant.sqrt()) / a
-    }
-}
+pub use std::f64::consts::PI;
 
 fn ray_color(r: &Ray, world: &dyn Hittable, depth: isize) -> Color {
     // If we've exceeded the ray bounce limit, no more light is gathered.
@@ -60,7 +48,7 @@ fn main() {
 
     // Image
     let aspect_ratio = 16.0 / 9.0;
-    let image_width = 400;
+    // let image_width = 400;
     let image_width = 1000;
     // let image_width = 1600;
     let image_height = (image_width as f64 / aspect_ratio) as i32;
@@ -69,6 +57,7 @@ fn main() {
 
     // World
     let mut world = HittableList::empty();
+
     let material_ground: MaterialPtr = Arc::new(Lambertian::new(Color::new(0.8, 0.8, 0.0)));
     let material_center: MaterialPtr = Arc::new(Lambertian::new(Color::new(0.1, 0.2, 0.5)));
     let material_left: MaterialPtr = Arc::new(Dielectric::new(1.5));
@@ -101,7 +90,13 @@ fn main() {
     )));
 
     // Camera
-    let cam = Camera::new();
+    let cam = Camera::new(
+        Point3::new(-2., 2., 1.),
+        Point3::new(0., 0., -1.),
+        Point3::new(0., 1., 0.),
+        20.0,
+        aspect_ratio,
+    );
 
     // Render
 
diff --git a/src/material.rs b/src/material.rs
index d791b28..6b9f065 100644
--- a/src/material.rs
+++ b/src/material.rs
@@ -22,7 +22,7 @@ impl Lambertian {
 }
 
 impl Material for Lambertian {
-    fn scatter(&self, r_in: &Ray, rec: &HitRecord) -> Option<(Color, Ray)> {
+    fn scatter(&self, _r_in: &Ray, rec: &HitRecord) -> Option<(Color, Ray)> {
         let mut scatter_direction = rec.normal + random_unit_vector();
         // Catch degenerate scatter direction
         if scatter_direction.near_zero() {
@@ -84,7 +84,7 @@ impl Material for Dielectric {
     fn scatter(&self, r_in: &Ray, rec: &HitRecord) -> Option<(Color, Ray)> {
         let attenuation = Color::new(1.0, 1.0, 1.0);
         let refraction_ratio = if rec.front_face {
-            (1.0 / self.ir)
+            1.0 / self.ir
         } else {
             self.ir
         };
-- 
2.45.2