added camera movement && a nice bokeh

src/camera.rs

@@ -7,29 +7,48 @@ pub struct Camera {
     lower_left_corner: Point3,
     horizontal: Vec3,
     vertical: Vec3,
+    u: Vec3,
+    v: Vec3,
+    w: Vec3,
+    lens_radius: f64,    
 }
 
 impl Camera {
-    pub fn new(vfov: f64, aspect_ratio: f64) -> Self {
+    pub fn new(
+        lookfrom: Point3,
+        lookat: Point3,
+        vup: Vec3,
+        vfov: f64,
+        aspect_ratio: f64,
+        apeture: f64,
+        focus_dist: f64,
+    ) -> Self {
         let theta = degrees_to_radians(vfov);
         let h = f64::tan(theta/2.0);
         let viewport_height = 2.0 * h;
         let viewport_width = aspect_ratio * viewport_height;
 
-        let focal_length = 1.0;
-        
-        let origin = Point3::new(0.0, 0.0, 0.0);
-        let horizontal = Vec3::new(viewport_width, 0.0, 0.0);
-        let vertical = Vec3::new(0.0, viewport_width, 0.0);
-        let lower_left_corner = origin - horizontal / 2.0 - vertical / 2.0 - Vec3::new(0.0, 0.0, focal_length);
+        let w = (lookfrom - lookat).unit_vector();
+        let u = (vup.cross(&w)).unit_vector();
+        let v = w.cross(&u);
 
-        Camera { origin, lower_left_corner, horizontal, vertical}
+        let origin = lookfrom;
+        let horizontal = focus_dist * viewport_width * u;
+        let vertical = focus_dist * viewport_height * v;
+        let lower_left_corner = origin - horizontal/2.0 - vertical/2.0 - focus_dist * w;
+
+        let lens_radius = apeture / 2.0;
+
+        Camera { origin, lower_left_corner, horizontal, vertical, u, v, w, lens_radius}
     }
 
-    pub fn get_ray(&self, u: f64, v: f64) -> Ray {
+    pub fn get_ray(&self, s: f64, t: f64) -> Ray {
+        let rd = self.lens_radius * random_in_unit_disk();
+        let offset = self.u * rd.x() + self.v * rd.y();
+
         Ray {
             origin: self.origin,
-            direction: self.lower_left_corner + u * self.horizontal + v * self.vertical - self.origin
+            direction: self.lower_left_corner + s*self.horizontal + t*self.vertical - self.origin - offset
         }
     }
 }

src/main.rs

@@ -58,7 +58,7 @@ fn main() {
     static MATERIAL_GROUND: Lambertian = Lambertian::new(Color::new(0.3, 0.8, 0.0));
     static MATERIAL_CENTER: Lambertian = Lambertian::new(Color::new(0.1, 0.2, 0.5));
     static MATERIAL_LEFT: Dielectric = Dielectric::new(1.5);
-    static MATERIAL_RIGHT: Metal = Metal::new(Color::new(0.8, 0.6, 0.2), 0.3);
+    static MATERIAL_RIGHT: Metal = Metal::new(Color::new(0.8, 0.6, 0.2), 0.0);
 
     world.add(Box::new(Sphere::new(Point3::new(0.0, -100.5, -1.0), 100.0, &MATERIAL_GROUND)));
     world.add(Box::new(Sphere::new(Point3::new(0.0, 0.0, -1.0), 0.5, &MATERIAL_CENTER)));
@@ -66,7 +66,20 @@ fn main() {
     world.add(Box::new(Sphere::new(Point3::new(1.0, 0.0, -1.0), 0.5, &MATERIAL_RIGHT)));
 
     // Camera
-    let cam = Camera::new(90.0, aspect_ratio);
+    let lookfrom = Point3::new(-2.0, 2.0, 1.0);
+    let lookat = Point3::new(0.0, 0.0, -1.0);
+    let vup = Vec3::new(0.0, 1.0, 0.0);
+    let dist_to_focus = (lookfrom-lookat).length_squared();
+
+    let cam = Camera::new(
+        lookfrom,
+        lookat,
+        vup,
+        30.0,
+        aspect_ratio,
+        0.0,
+        dist_to_focus
+    );
 
     // Render
     //let mut rng = rand::thread_rng();

src/vec3.rs

@@ -45,9 +45,9 @@ impl Vec3 {
     pub fn cross(&self, rhs: &Self) -> Self {
         Self {
             elements: [
-                self.y() * rhs.z() + self.z() * rhs.y(),
-                self.z() * rhs.x() + self.x() * rhs.z(),
-                self.x() * rhs.y() + self.y() * rhs.x()
+                self.y() * rhs.z() - self.z() * rhs.y(),
+                self.z() * rhs.x() - self.x() * rhs.z(),
+                self.x() * rhs.y() - self.y() * rhs.x()
             ]
         }
     }
@@ -247,4 +247,14 @@ pub fn refract(uv: &Vec3, n: &Vec3, etai_over_etat: f64) -> Vec3 {
     let r_out_parallel = -f64::sqrt(f64::abs(1.0 - r_out_perp.length_squared())) * *n;
     
     r_out_perp + r_out_parallel
+}
+
+pub fn random_in_unit_disk() -> Vec3 {
+    loop {
+        let p = Vec3::new(random_range_f64(-1.0, 1.0), random_range_f64(-1.0, 1.0), 0.0);
+        if p.length_squared() >= 1.0 {
+            continue;
+        }
+        return p;
+    }
 }