Added materials

src/main.rs

@@ -2,69 +2,47 @@ mod image;
 mod object;
 mod render;
 mod vec3;
+mod material;
 
-use image::Image;
 use object::Sphere;
-use render::World;
+use render::{World,Camera};
-use vec3::{Point3, Ray, Vec3};
+use vec3::{Point3,Vec3};
+
+use material::{Metal,Lambertian,Material};
+
 
-use crate::vec3::Interval;
 
 fn main() {
     let aspect_ratio = 16.0 / 9.0;
     let image_width = 800;
-    let image_height = (image_width as f64 / aspect_ratio) as i32;
-
     let focal_length = 1.0;
     let viewport_height = 2.0;
-    let viewport_width = viewport_height * (image_width as f64 / image_height as f64);
     let camera_center = Point3::new(0.0, 0.0, 0.0);
 
-    let viewport_u = Vec3::new(viewport_width as f64, 0.0, 0.0);
-    let viewport_v = Vec3::new(0.0, -viewport_height as f64, 0.0);
 
-    let pixel_delta_u = viewport_u / image_width as f64;
+    let m = Lambertian::new(Vec3::new(0.5,0.5,0.5));
-    let pixel_delta_v = viewport_v / image_height as f64;
+    let b: Box <dyn Material> = Box::new(m);
+    let world_m = std::rc::Rc::new(b);
 
-    let viewport_upper_left = (camera_center.to_vec()
+    let m = Lambertian::new(Vec3::new(0.1, 0.2, 0.5));
-        - Vec3::new(0.0, 0.0, focal_length)
+    let b: Box <dyn Material> = Box::new(m);
-        - viewport_u / 2.0
+    let center_m = std::rc::Rc::new(b);
-        - viewport_v / 2.0)
-        .to_point();
 
-    let pixel00_loc = viewport_upper_left + ((pixel_delta_u + pixel_delta_v) * 0.5).to_point();
+    let m = Metal::new(Vec3::new(0.8, 0.8, 0.8), 0.3);
+    let b: Box <dyn Material> = Box::new(m);
+    let left_m = std::rc::Rc::new(b);
 
-    let mut img = Image::new(image_width, image_height);
 
+    let m = Metal::new(Vec3::new(0.8, 0.6, 0.2), 0.5);
+    let b: Box <dyn Material> = Box::new(m);
+    let right_m = std::rc::Rc::new(b);
+
+    let mut camera = Camera::new(aspect_ratio,image_width,focal_length,viewport_height,camera_center);
     let mut world = World::new();
-    world.add(Sphere::new(0.5, Point3::new(0.0, 0.0, -1.0)));
+    world.add(Sphere::new(0.5, Point3::new(0.0, 0.0, -1.0),center_m));
-    world.add(Sphere::new(100.0, Point3::new(0.0, -100.5, -1.0)));
+    world.add(Sphere::new(0.5, Point3::new(-1.0, 0.0, -1.0),left_m));
+    world.add(Sphere::new(0.5, Point3::new(1.0, 0.0, -1.0),right_m));
+    world.add(Sphere::new(100.0, Point3::new(0.0, -100.5, -1.0),world_m));
 
-    for y in 0..img.height {
+    camera.render(&world);
-        for x in 0..img.width {
-            if let Some(px) = img.get_pixel(x, y) {
-                let pixel_center = pixel00_loc
-                    + ((pixel_delta_u * x as f64) + (pixel_delta_v * y as f64)).to_point();
-                let ray_direction = (pixel_center - camera_center).to_vec();
-                let ray = Ray::new(camera_center, ray_direction);
-                let (r, g, b) = color_ray(ray);
-		let i = Interval::new(0.001,f64::INFINITY);
-                if let Some(hit) = world.hit(ray, i) {
-                    let (r,g,b) = hit.color();
-                    px.set_color(r,g,b);
-                } else {
-                    px.set_color(r, g, b);
-                }
-            } else {
-            }
-        }
-    }
-    img.save("./foo.ppm").unwrap();
-}
-
-fn color_ray(ray: Ray) -> (f64, f64, f64) {
-    let unit_direction = ray.direction().unit();
-    let a = 0.5 * unit_direction.y() + 1.0;
-    let b = 1.0 - a;
-    (b + 0.5 * a, b + 0.7 * a, b + 1.0 * a)
 }

src/material.rs

@@ -0,0 +1,92 @@
+use crate::vec3::{Ray,Vec3};
+use crate::object::HitRecord;
+
+use rand::prelude::*;
+
+
+pub struct Scatter {
+    pub attenuation: Vec3,
+    pub ray: Ray,
+}
+
+pub trait Material {
+    fn scatter(&self, r_in: &Ray, rec: &HitRecord, rng: &mut ThreadRng) -> Option<Scatter>;
+}
+
+
+#[derive(Clone, Copy)]
+pub struct Metal {
+    pub albedo: Vec3,
+    pub fuzz: f64,
+}
+
+impl Metal {
+    pub fn new(albedo: Vec3, f: f64) -> Self {
+        Self {
+            albedo,
+            fuzz: if f < 1.0 { f } else { 1.0 },
+        }
+    }
+}
+
+impl Material for Metal {
+    fn scatter(&self, r_in: &Ray, rec: &HitRecord, rng: &mut ThreadRng) -> Option<Scatter> {
+        let reflected = reflect(r_in.direction().unit(), rec.normal());
+        let scattered_ray = Ray::new(
+            rec.point(), 
+            reflected + random_in_unit_sphere(rng) * self.fuzz
+        );
+
+        if scattered_ray.direction().dot(rec.normal()) > 0.0 {
+            Some(Scatter {
+                attenuation: self.albedo,
+                ray: scattered_ray,
+            })
+        } else {
+            None
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub struct Lambertian {
+    pub albedo: Vec3,
+}
+
+
+impl Lambertian {
+    pub fn new(albedo: Vec3) -> Self {
+        Self {
+            albedo,
+        }
+    }
+}
+
+impl Material for Lambertian {
+    fn scatter(&self, _r_in: &Ray, rec: &HitRecord, rng: &mut ThreadRng) -> Option<Scatter> {
+        let target = rec.point().to_vec() + rec.normal() + random_in_unit_sphere(rng);
+        
+        Some(Scatter {
+            attenuation: self.albedo,
+            ray: Ray::new(rec.point(), target - rec.point().to_vec()),
+        })
+    }
+}
+
+
+fn reflect(v: Vec3, n: Vec3) -> Vec3 {
+    v - n * 2.0 * v.dot(n)
+}
+
+fn random_in_unit_sphere(rng: &mut ThreadRng) -> Vec3 {
+    loop {
+        let p = Vec3::new(
+            rng.random_range(-1.0..1.0),
+            rng.random_range(-1.0..1.0),
+            rng.random_range(-1.0..1.0),
+        );
+        if p.length_squared() < 1.0 {
+            return p;
+        }
+    }
+}

src/object.rs

@@ -1,49 +1,54 @@
 use crate::vec3::{Point3, Ray, Vec3, Interval};
+use crate::material::{Material,Scatter};
+
+use rand::prelude::*;
+
 
 pub trait Hittable {
     fn hit(&self, ray: Ray, interval:Interval) -> Option<HitRecord>;
 }
 
-#[derive(Clone, Copy)]
 pub struct HitRecord {
     point: Point3,
     normal: Vec3,
     root: f64,
     front_face: bool,
-    color: (f64,f64,f64)
+    material: std::rc::Rc<Box<dyn Material>>,
 }
 
 impl HitRecord {
-    pub fn normal(self) -> Vec3 {
+    pub fn normal(&self) -> Vec3 {
         self.normal
     }
 
-    pub fn point(self) -> Point3 {
+    pub fn point(&self) -> Point3 {
         self.point
     }
 
-    pub fn root(self) -> f64 {
+    pub fn root(&self) -> f64 {
         self.root
     }
 
-    pub fn color(self) -> (f64,f64,f64) {
-        self.color
-    }
-
     pub fn set_face_normal(&mut self, ray: Ray, norm: Vec3) {
         self.front_face = ray.direction().dot(norm) < 0.0;
         self.normal = if self.front_face { norm } else { norm * -1.0 };
     }
+
+    pub fn scatter(&self, r_in: &Ray, rng: &mut ThreadRng) -> Option<Scatter>{
+	self.material.scatter(r_in,&self,rng)
+    }
+
 }
 
 pub struct Sphere {
     radius: f64,
     center: Point3,
+    material: std::rc::Rc<Box<dyn Material>>
 }
 
 impl Sphere {
-    pub fn new(radius: f64, center: Point3) -> Self {
+    pub fn new(radius: f64, center: Point3, material:std::rc::Rc<Box<dyn Material>>) -> Self {
-        Sphere { radius, center }
+        Sphere { radius, center , material}
     }
 }
 
@@ -74,7 +79,7 @@ impl Hittable for Sphere {
             point,
             normal,
             front_face: false,
-	    color: (normal.x(),normal.y(),normal.z())
+	    material: self.material.clone()
         };
         tmp.set_face_normal(ray, normal);
         Some(tmp)

src/render.rs

@@ -1,5 +1,8 @@
 use crate::object::{HitRecord, Hittable};
-use crate::vec3::{Interval, Ray};
+use crate::vec3::{Interval, Ray, Vec3, Point3};
+use crate::image::Image;
+
+use rand::prelude::*;
 
 pub struct World {
     pub objects: Vec<Box<dyn Hittable>>,
@@ -7,26 +10,129 @@ pub struct World {
 
 impl World {
     pub fn new() -> Self {
-        World {
+	World {
-            objects: Vec::new(),
+	    objects: Vec::new(),
-        }
+	}
     }
 
     pub fn add(&mut self, object: impl Hittable + 'static) {
-        self.objects.push(Box::new(object));
+	self.objects.push(Box::new(object));
     }
 
     pub fn hit(&self, ray: Ray, interval:Interval) -> Option<HitRecord> {
-        let mut hit_anything = None;
+	let mut hit_anything = None;
-        let mut closest_so_far = interval.max();
+	let mut closest_so_far = interval.max();
 
-        for object in &self.objects {
+	for object in &self.objects {
 	    let i = Interval::new(interval.min(),closest_so_far);
-            if let Some(record) = object.hit(ray, i) {
+	    if let Some(record) = object.hit(ray, i) {
-                closest_so_far = record.root();
+		closest_so_far = record.root();
-                hit_anything = Some(record);
+		hit_anything = Some(record);
-            }
+	    }
-        }
+	}
-        hit_anything
+	hit_anything
     }
 }
+
+
+pub struct Camera {
+    img: Image,
+    pixel00_loc: Point3,
+    camera_center: Point3,
+    pixel_delta_u: Vec3,
+    pixel_delta_v: Vec3
+}
+
+impl Camera {
+    pub fn new(aspect_ratio:f64,image_width: i32, focal_length:f64, viewport_height:f64, camera_center: Point3) -> Self{
+
+	let image_height = (image_width as f64 / aspect_ratio) as i32;
+
+	let viewport_width = viewport_height * (image_width as f64 / image_height as f64);
+
+	let viewport_u = Vec3::new(viewport_width as f64, 0.0, 0.0);
+	let viewport_v = Vec3::new(0.0, -viewport_height as f64, 0.0);
+
+	let pixel_delta_u = viewport_u / image_width as f64;
+	let pixel_delta_v = viewport_v / image_height as f64;
+
+	let viewport_upper_left = (camera_center.to_vec()
+				   - Vec3::new(0.0, 0.0, focal_length)
+				   - viewport_u / 2.0
+				   - viewport_v / 2.0).to_point();
+
+	let pixel00_loc = viewport_upper_left + ((pixel_delta_u + pixel_delta_v) * 0.5).to_point();
+
+	let img = Image::new(image_width, image_height);
+	Self{img,pixel00_loc,camera_center,pixel_delta_u,pixel_delta_v}
+    }
+
+
+    pub fn render(&mut self, world: &World){
+	let mut rng:ThreadRng = rand::rng();
+	for y in 0..self.img.height {
+	    for x in 0..self.img.width {
+		let (mut r,mut g,mut b) = (0.0,0.0,0.0);
+		let num_samples=10.0;
+		let depth=10;
+		for _ in 0..num_samples as i32{
+		    let ray = self.get_ray(x,y,&mut rng);
+		    let (tr,tg,tb)= trace(ray, &world,depth,&mut rng);
+		    r+= tr;
+		    g+= tg;
+		    b+= tb;
+		}
+		r /= num_samples;
+		g /= num_samples;
+		b /= num_samples;
+
+		r = r.clamp(0.0,1.0).sqrt();
+		g = g.clamp(0.0,1.0).sqrt();
+		b = b.clamp(0.0,1.0).sqrt();
+		if let Some(px) = self.img.get_pixel(x,y){
+		    px.set_color(r,g,b);
+		} else{/*ignore*/}
+	    }
+	}
+	self.img.save("./foo.ppm").unwrap();
+    }
+
+    fn get_ray(&self, x:i32,y:i32,rng:&mut ThreadRng) -> Ray{
+	let offset = 0.005;
+	let rnd_vec = Vec3::new(rng.random_range(-offset..offset),rng.random_range(-offset..offset),0.0);
+	let pixel_center = self.pixel00_loc
+	    + ((self.pixel_delta_u * (x as f64 + rnd_vec.x())) + (self.pixel_delta_v * (y as f64 + rnd_vec.y()))).to_point();
+	let ray_direction = (pixel_center - self.camera_center).to_vec();
+	Ray::new(self.camera_center, ray_direction)//+rnd_vec)
+    }
+
+}
+
+fn trace(ray: Ray, world: &World, depth: i32, rng: &mut ThreadRng) -> (f64, f64, f64) {
+    let i = Interval::new(0.001, f64::INFINITY);
+    if depth <= 0 {
+	return (0.0, 0.0, 0.0);
+    }
+
+    if let Some(hit) = world.hit(ray, i) {
+	if let Some(scatter_record) = hit.scatter(&ray, rng) {
+	    let (tr, tg, tb) = trace(scatter_record.ray, world, depth - 1, rng);
+	    let r = scatter_record.attenuation.x() * tr;
+	    let g = scatter_record.attenuation.y() * tg;
+	    let b = scatter_record.attenuation.z() * tb;
+
+	    return (r, g, b);
+	} else {
+	    return (0.0, 0.0, 0.0);
+	}
+    } else {
+	color_ray(ray)
+    }
+}
+
+fn color_ray(ray: Ray) -> (f64, f64, f64) {
+    let unit_direction = ray.direction().unit();
+    let a = 0.5 * unit_direction.y() + 1.0;
+    let b = 1.0 - a;
+    (b + 0.5 * a, b + 0.7 * a, b + 1.0 * a)
+}