Toy with different teapot scenes

.gitignore

@@ -3,3 +3,4 @@
 .idea
 *.iml
 .vscode/
+*.png

Cargo.lock

@@ -14,6 +14,17 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aae1277d39aeec15cb388266ecc24b11c80469deae6067e17a1a7aa9e5c1f234"
 
+[[package]]
+name = "ahash"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
+dependencies = [
+ "getrandom",
+ "once_cell",
+ "version_check",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@@ -324,6 +335,7 @@ dependencies = [
  "image",
  "rand",
  "rayon",
+ "tobj",
 ]
 
 [[package]]
@@ -332,6 +344,21 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
+[[package]]
+name = "tobj"
+version = "3.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "deacee3abcc4fd8ff3f0f7c08d4583ab51753ed1d5a3acacd6d5773f640c27d6"
+dependencies = [
+ "ahash",
+]
+
+[[package]]
+name = "version_check"
+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"

Cargo.toml

@@ -10,6 +10,7 @@ include = ["/src"]
 image = { version = "0.24.2", default-features = false, features=["png", "jpeg", "jpeg_rayon"] }
 rand = "0.8.5"
 rayon = "1.5.3"
+tobj = "3.2.3"
 
 [profile.release]
 debug = 1

src/aabb.rs

@@ -20,9 +20,7 @@ impl Default for Aabb {
 }
 
 impl Aabb {
-    pub fn hit(&self, ray: &Ray, t_min: f64, t_max: f64) -> bool {
-        let mut t_min = t_min;
-        let mut t_max = t_max;
+    pub fn hit(&self, ray: &Ray, mut t_min: f64, mut t_max: f64) -> bool {
         for a in 0..3 {
             let inv_d = 1.0 / ray.direction()[a];
             let mut t0 = (self.minimum[a] - ray.origin()[a]) * inv_d;
@@ -42,11 +40,11 @@ impl Aabb {
         let minimum = Point3::new(
             self.minimum.x().min(other.minimum.x()),
             self.minimum.y().min(other.minimum.y()),
-            self.minimum.y().min(other.minimum.z()));
+            self.minimum.z().min(other.minimum.z()));
         let maximum = Point3::new(
             self.maximum.x().max(other.maximum.x()),
             self.maximum.y().max(other.maximum.y()),
-            self.maximum.y().max(other.maximum.z()));
+            self.maximum.z().max(other.maximum.z()));
         Aabb {minimum, maximum}
     }
 }

src/bvh.rs

@@ -83,10 +83,7 @@ impl Hittable for BVH {
                 let hit_left = left.hit(ray, t_min, t_max);
                 if let Some(hl) = &hit_left { t_max = hl.t };
                 let hit_right = right.hit(ray, t_min, t_max);
-                match hit_left {
-                    Some(hit_left) => Some(hit_left),
-                    _ => hit_right
-                }
+                if hit_right.is_some() { hit_right } else { hit_left }
             }
         }
     }

src/constant_medium.rs

@@ -0,0 +1,88 @@
+use std::sync::Arc;
+use crate::{Aabb, Color, Material, Ray, Vec3};
+use crate::hittable::{HitRecord, Hittable};
+use crate::isotropic::Isotropic;
+use crate::texture::Texture;
+
+/*
+#[derive(Clone, Copy)]
+pub struct HitRecord<'material> {
+    pub point: Point3,
+    pub normal: Vec3,
+    pub t: f64,
+    pub u: f64,
+    pub v: f64,
+    pub front_face: bool,
+    pub material: &'material Arc<Material>
+}
+ */
+
+pub struct ConstantMedium<H: Hittable> {
+    boundary: H,
+    phase_function: Arc<Material>,
+    neg_inv_density: f64
+}
+
+impl<H: Hittable,> ConstantMedium<H> {
+    pub fn new(boundary: H, phase_function: Arc<Material>, density: f64) -> Self {
+        Self {
+            boundary,
+            phase_function,
+            neg_inv_density: -1.0 / density
+        }
+    }
+    pub fn textured(boundary: H, texture: Arc<dyn Texture>, density: f64) -> Self {
+        Self {
+            boundary,
+            phase_function: Arc::new(Material::Isotropic(Isotropic::from(texture))),
+            neg_inv_density: -1.0 / density
+        }
+    }
+    pub fn colored(boundary: H, color: Color, density: f64) -> Self {
+        Self {
+            boundary,
+            phase_function: Arc::new(Material::Isotropic(Isotropic::from(color))),
+            neg_inv_density: -1.0 / density
+        }
+    }
+}
+
+impl<H: Hittable>Hittable for ConstantMedium<H>{
+    fn hit(&self, ray: &Ray, t_min: f64, t_max: f64) -> Option<HitRecord> {
+        let rec1 = self.boundary.hit(ray, f64::NEG_INFINITY, f64::INFINITY);
+        if rec1.is_none() {
+            return None;
+        }
+        let mut rec1 = rec1.unwrap();
+
+        let rec2 = self.boundary.hit(ray, rec1.t+0.0001, f64::INFINITY);
+        if rec2.is_none() {
+            return None;
+        }
+        let mut rec2 = rec2.unwrap();
+        if rec1.t < t_min { rec1.t = t_min; }
+        if rec2.t > t_max { rec2.t = t_max; }
+        if rec1.t > rec2.t { return None; }
+        if rec1.t < t_min { rec1.t = 0.0; }
+
+        let ray_length = ray.direction().length();
+        let distance_inside_boundary = (rec2.t - rec1.t) * ray_length;
+        let hit_distance = self.neg_inv_density * rand::random::<f64>().ln();
+
+        if hit_distance > distance_inside_boundary { return None; }
+        let t = rec1.t + hit_distance / ray_length;
+        Some(HitRecord {
+            point: ray.at(t),
+            normal: Vec3::new(1.0, 0.0, 0.0), // arbitrary
+            t,
+            u: 0.0,
+            v: 0.0,
+            front_face: true, // also arbitrary
+            material: &self.phase_function
+        })
+    }
+
+    fn bounding_box(&self, time0: f64, time1: f64) -> Option<Aabb> {
+        self.boundary.bounding_box(time0, time1)
+    }
+}

src/image_texture.rs

@@ -1,11 +1,4 @@
-/*
-        let img = image::open("tests/images/jpg/progressive/cat.jpg").unwrap();
-        let rgnbi = img.into_rgb8();
-        rgnbi.get_pixel(0, 0);
-        rgnbi.
-
- */
-use image::{Pixel, RgbImage};
+use image::{RgbImage};
 use crate::{Color, Point3};
 use crate::texture::Texture;
 

src/isotropic.rs

@@ -0,0 +1,33 @@
+use std::sync::Arc;
+use crate::hittable::HitRecord;
+use crate::{Color, Ray, Vec3};
+use crate::texture::{SolidColor, Texture};
+
+pub struct Isotropic {
+    pub albedo: Arc<dyn Texture>
+}
+
+impl Isotropic {
+    pub fn scatter(&self, ray: &Ray, hit_record: &HitRecord) -> Option<(Option<Ray>, Color)> {
+        Some((
+            Some(
+                Ray::new(
+                hit_record.point,
+                Vec3::random_in_unit_sphere(),
+                ray.time())),
+            self.albedo.value(hit_record.u, hit_record.v, &hit_record.point)
+        ))
+    }
+}
+
+impl From<Color> for Isotropic {
+    fn from(albedo: Color) -> Self {
+        let texture = SolidColor::from(albedo);
+        Isotropic { albedo: Arc::new(texture) }
+    }
+}
+impl From<Arc<dyn Texture>> for Isotropic {
+    fn from(albedo: Arc<dyn Texture>) -> Self {
+        Isotropic { albedo }
+    }
+}

src/main.rs

@@ -11,14 +11,18 @@ use rand::distributions::{Distribution, Uniform};
 use rayon::iter::{IntoParallelIterator, ParallelIterator};
 use crate::material::{Dielectric, DiffuseLight, Lambertian, Material, Metal};
 use crate::aabb::Aabb;
+use crate::bvh::BVH;
+use crate::constant_medium::ConstantMedium;
 use crate::cuboid::Cuboid;
 use crate::image_texture::ImageTexture;
 use crate::noise::NoiseTexture;
+use crate::obj::obj_to_hitable;
 use crate::perlin::Perlin;
 use crate::texture::CheckerTexture;
 use crate::rect::{Plane, Rect2D};
 use crate::rotate_y::RotateY;
 use crate::translate::Translate;
+use crate::triangle::Triangle;
 
 mod vec3;
 mod ray;
@@ -36,10 +40,14 @@ mod rect;
 mod cuboid;
 mod translate;
 mod rotate_y;
+mod constant_medium;
+mod isotropic;
+mod obj;
+mod triangle;
 
 // Image
 const DEFAULT_ASPECT_RATIO: f64 = 3.0 / 2.0;
-const IMAGE_WIDTH: usize = 400;
+const IMAGE_WIDTH: usize = 300;
 const SAMPLES_PER_PIXEL: i32 = 100;
 const MAX_DEPTH: i32 = 50;
 
@@ -49,6 +57,66 @@ struct Scene {
     pub background: Color
 }
 
+fn obj(path: &str) -> Scene {
+    let object = obj_to_hitable(&std::path::Path::new(path));
+    print!("Object hitbox: {:#?}", object.bounding_box(0.0, 1.0));
+
+    let difflight = Arc::new(Material::white_light(4.0));
+
+    let world: HittableList = vec![
+        object,
+        Arc::new(Rect2D::new(
+        Plane::XZ,
+        -2.0,
+        2.0,
+        -2.0,
+        2.0,
+        10.0,
+        difflight.clone()
+    )),
+        Arc::new(Sphere::new(
+            Point3::new(-5.0, 5.0, 0.0),
+        1.0,
+        difflight.clone()
+    )),
+        Arc::new(Sphere::new(
+            Point3::new(0.6, 3.5, -0.6),
+        0.4,
+        Arc::new(Material::Metal(Metal::new(Color::new(1.0, 0.0, 0.0), 0.2)))
+    )),
+        Arc::new(Sphere::new(
+            Point3::new(1.7, 0.4, 1.7),
+        0.4,
+        Arc::new(Material::solid(0.2, 0.2, 0.8))
+    )),
+        Arc::new(Sphere::new(
+        Point3::new(0.0, 300.0, 0.0),
+        300.0,
+        Arc::new(Material::Lambertian(Lambertian::textured(Arc::new(NoiseTexture { noise: Perlin::new(), scale: 0.1 }))))
+    ))];
+
+    let look_from = Point3::new(8.0, 10.0, 8.0);
+    let look_at = Point3::new(0.0, 1.0, 0.0);
+    let focus_dist = 2.0;
+
+    let cam = Camera::new(
+        look_from,
+        look_at,
+        Vec3::new(0.0, 1.0, 0.0),
+        1.0,
+        30.0,
+        0.0,
+        focus_dist,
+        0.0,
+        1.0);
+
+    Scene {
+        world,
+        cam,
+        background: Color::default()
+    }
+}
+
 fn cornell_box() -> Scene {
     let mut world:HittableList = Vec::new();
     let red = Material::Lambertian(
@@ -117,6 +185,7 @@ fn cornell_box() -> Scene {
     )));
 
     // Boxes
+
     let rotated1 = RotateY::new(
         Cuboid::new(
             Point3::new(0.0, 0.0, 0.0),
@@ -144,6 +213,131 @@ fn cornell_box() -> Scene {
     );
     world.push(Arc::new(box2));
 
+    let look_from = Point3::new(278.0, 278.0, -800.0);
+    let look_at = Point3::new(278.0, 278.0, 0.0);
+    let focus_dist = 2.0;
+
+    let cam = Camera::new(
+        look_from,
+        look_at,
+        Vec3::new(0.0, 1.0, 0.0),
+        1.0,
+        40.0,
+        0.0,
+        focus_dist,
+        0.0,
+        1.0);
+
+    Scene {
+        world,
+        cam,
+        background: Color::default()
+    }
+}
+
+fn cornell_box_smoke() -> Scene {
+    let mut world:HittableList = Vec::new();
+    let red = Material::Lambertian(
+        Lambertian::from(Color::new(0.65, 0.05, 0.05)));
+    let white = Arc::new(Material::Lambertian(
+        Lambertian::from(Color::new(0.73, 0.73, 0.73))));
+    let green = Material::Lambertian(
+        Lambertian::from(Color::new(0.12, 0.45, 0.15)));
+    let light = Material::DiffuseLight(
+        DiffuseLight::from(Color::new(7.0, 7.0, 7.0)));
+
+    // Walls
+    world.push(Arc::new(Rect2D::new(
+        Plane::YZ,
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        555.0,
+        Arc::new(green)
+    )));
+    world.push(Arc::new(Rect2D::new(
+        Plane::YZ,
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        0.0,
+        Arc::new(red)
+    )));
+    world.push(Arc::new(Rect2D::new(
+        Plane::XZ,
+        113.0,
+        443.0,
+        127.0,
+        432.0,
+        554.0,
+        Arc::new(light)
+    )));
+    world.push(Arc::new(Rect2D::new(
+        Plane::XZ,
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        0.0,
+        white.clone()
+    )));
+    world.push(Arc::new(Rect2D::new(
+        Plane::XZ,
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        555.0,
+        white.clone()
+    )));
+    world.push(Arc::new(Rect2D::new(
+        Plane::XY,
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        555.0,
+        white.clone()
+    )));
+
+    // Boxes
+
+    let rotated1 = RotateY::new(
+        Cuboid::new(
+            Point3::new(0.0, 0.0, 0.0),
+            Point3::new(165.0, 330.0, 165.0),
+            white.clone()
+        ),
+        15.0
+    );
+    let box1 = Translate::new(
+        rotated1,
+        Vec3::new(265.0, 0.0, 295.0)
+    );
+    let medium1 = ConstantMedium::colored(
+        box1,
+        Color::new(0.0, 0.0, 0.0),
+        0.01);
+    world.push(Arc::new(medium1));
+    let rotated2 = RotateY::new(
+        Cuboid::new(
+            Point3::new(0.0, 0.0, 0.0),
+            Point3::new(165.0, 165.0, 165.0),
+            white.clone()
+        ),
+        -18.0
+    );
+    let box2 = Translate::new(
+        rotated2,
+        Vec3::new(130.0,0.0,65.0)
+    );
+    let medium2 = ConstantMedium::colored(
+        box2,
+        Color::new(1.0, 1.0, 1.0),
+        0.01);
+    world.push(Arc::new(medium2));
 
     let look_from = Point3::new(278.0, 278.0, -800.0);
     let look_at = Point3::new(278.0, 278.0, 0.0);
@@ -474,9 +668,176 @@ fn random_scene() -> Scene {
     }
 }
 
+fn next_week_final() -> Scene {
+    let ground = Arc::new(
+        Material::Lambertian(Lambertian::from(Color::new(0.48, 0.84, 0.53))));
+    let boxes_per_side = 20;
+    let mut rng = rand::thread_rng();
+    let box_range = Uniform::from(1.0..101.0);
+    let mut boxes1: HittableList = Vec::with_capacity(boxes_per_side*boxes_per_side);
+    for i in 0..boxes_per_side {
+        for j in 0..boxes_per_side {
+            let w = 100.0;
+            let x0 = -1000.0 + (i as f64)*w;
+            let z0 = -1000.0 + (j as f64)*w;
+            let y0 = 0.0;
+            let x1 = x0 + w;
+            let y1 = box_range.sample(&mut rng);
+            let z1 = z0 + w;
+            boxes1.push(Arc::new(Cuboid::new(
+                Vec3::new(x0, y0, z0),
+                Vec3::new(x1, y1, z1),
+                ground.clone()
+            )));
+        }
+    }
+
+    let mut world: HittableList = Vec::new();
+    world.push(Arc::new(BVH::new(boxes1, 0.0, 1.0)));
+
+    let light = Arc::new(
+        Material::DiffuseLight(DiffuseLight::from(Color::new(7.0, 7.0, 7.0))));
+    world.push(Arc::new(Rect2D::new(
+        Plane::XZ,
+        123.0,
+        423.0,
+        147.0,
+        412.0,
+        554.0,
+        light
+    )));
+
+    // Moving Sphere
+    let moving_sphere_material = Arc::new(
+        Material::Lambertian(Lambertian::from(Color::new(0.7, 0.3, 0.1))));
+    let center1 = Point3::new(400.0, 400.0, 200.0);
+    world.push(Arc::new(MovableSphere::new(
+        center1,
+        center1 + Vec3::new(30.0, 0.0, 0.0),
+        50.0,
+        moving_sphere_material,
+        0.0,
+        1.0
+    )));
+
+    let glass = Arc::new(Material::Dielectric(Dielectric::new(1.5)));
+
+    // Glass
+    world.push(Arc::new(Sphere::new(
+        Point3::new(260.0, 150.0, 45.0),
+        50.0,
+        glass.clone()
+    )));
+
+    // Metal sphere
+    world.push(Arc::new(Sphere::new(
+        Point3::new(0.0, 150.0, 145.0),
+        50.0,
+        Arc::new(
+            Material::Metal(Metal::new(Color::new(0.8, 0.8, 0.9), 1.0)))
+    )));
+    let boundary = Sphere::new(
+        Point3::new(360.0, 150.0, 145.0),
+        70.0,
+        glass.clone()
+    );
+    let boundary_clone = Sphere::new(
+        Point3::new(360.0, 150.0, 145.0),
+        70.0,
+        glass.clone()
+    );
+    world.push(Arc::new(boundary_clone));
+    world.push(Arc::new(
+        ConstantMedium::colored(
+            boundary,
+            Color::new(0.2, 0.4, 0.9),
+            0.2)));
+    let boundary = Sphere::new(
+        Point3::new(0.0, 0.0, 0.0),
+        5000.0,
+        glass.clone()
+    );
+    world.push(Arc::new(
+        ConstantMedium::colored(
+            boundary,
+            Color::new(1.0, 1.0, 1.0),
+            0.0001)));
+
+    // Earth
+    let earth_material = Arc::new(Material::Lambertian(
+        Lambertian::textured(
+            Arc::new(ImageTexture::new("textures/earthmap.jpg")))));
+    world.push(Arc::new(Sphere::new(
+        Point3::new(400.0, 200.0, 400.0),
+        100.0,
+        earth_material
+    )));
+
+    // Gray sphere
+    let pertext = Arc::new(Material::Lambertian(Lambertian::textured(
+        Arc::new(NoiseTexture {
+            noise: Perlin::new(),
+            scale: 0.1
+        }))));
+    world.push(Arc::new(Sphere::new(
+        Point3::new(220.0, 280.0, 300.0),
+        80.0,
+        pertext
+    )));
+
+    let ns = 1000;
+    let mut boxes2: HittableList = Vec::with_capacity(ns);
+    let white = Arc::new(Material::Lambertian(
+        Lambertian::from(Color::new(0.73, 0.73, 0.73))));
+
+
+    for _i in 0..ns {
+        let sphere = Sphere::new(
+            Point3::random(0.0, 165.0),
+            10.0,
+            white.clone()
+        );
+        boxes2.push(Arc::new(sphere));
+    }
+    world.push(
+        Arc::new(
+            Translate::new(
+                RotateY::new(
+                    BVH::new(boxes2, 0.0, 1.0),
+                    15.0
+                ),
+                Vec3::new(-100.0, 270.0, 395.0)
+            )
+        )
+    );
+
+
+    let look_from = Point3::new(478.0, 278.0, -600.0);
+    let look_at = Point3::new(278.0, 278.0, 0.0);
+    let focus_dist = 2.0;
+
+    let cam = Camera::new(
+        look_from,
+        look_at,
+        Vec3::new(0.0, 1.0, 0.0),
+        1.0,
+        40.0,
+        0.0,
+        focus_dist,
+        0.0,
+        1.0);
+
+    Scene {
+        world,
+        cam,
+        background: Color::default()
+    }
+}
+
 fn main() {
+    rayon::ThreadPoolBuilder::new().num_threads(1).build_global().unwrap(); // Enable, to reduce load
     // World
-    let scene: u8 = 5;
+    let scene: u8 = 8;
     let scene_setup = match scene {
         0 => two_spheres(),
         1 => two_perlin_spheres(),
@@ -484,6 +845,9 @@ fn main() {
         3 => sun(),
         4 => simple_light(),
         5 => cornell_box(),
+        6 => cornell_box_smoke(),
+        7 => next_week_final(),
+        8 => obj("teapot.obj"),
         _ => random_scene(),
     };
 
@@ -493,6 +857,7 @@ fn main() {
     let image_height: usize = (IMAGE_WIDTH as f64 / scene_setup.cam.aspect_ratio()) as usize;
     let mut pixels = vec![0; IMAGE_WIDTH * image_height * 3];
     let bands: Vec<(usize, &mut [u8])> = pixels.chunks_mut(3).enumerate().collect();
+
     let count = Mutex::new(0);
     bands.into_par_iter().for_each(|(i, pixel)| {
         let row = image_height - (i / IMAGE_WIDTH) - 1;
@@ -523,26 +888,3 @@ fn main() {
     PNG::write("imc.png", &pixels, IMAGE_WIDTH, image_height).expect("Error writing image: {}");
     eprintln!("\nDone. Time: {}ms", start.elapsed().as_millis());
 }
-
-fn world_bounding_box(time0: f64, time1: f64, world: &HittableList) -> Option<Aabb> {
-    if world.is_empty() {
-        return None;
-    }
-    let mut is_first = true;
-    let mut output_box: Aabb = Aabb {
-        minimum: Point3::default(),
-        maximum: Point3::default()
-    };
-    for object in world {
-        if let Some(bb) = object.bounding_box(time0, time1) {
-            output_box = match is_first {
-                true => bb,
-                false => output_box.surrounding(&bb)
-            };
-            is_first = false;
-        } else {
-            return None;
-        }
-    }
-    Some(output_box)
-}

src/material.rs

@@ -2,6 +2,7 @@ use std::sync::Arc;
 use rand::Rng;
 use crate::hittable::HitRecord;
 use crate::{Color, Point3, Ray, Vec3};
+use crate::isotropic::Isotropic;
 use crate::texture::{SolidColor, Texture};
 
 pub trait Scatterable {
@@ -13,12 +14,25 @@ pub enum Material {
     Lambertian(Lambertian),
     Metal(Metal),
     Dielectric(Dielectric),
-    DiffuseLight(DiffuseLight)
+    DiffuseLight(DiffuseLight),
+    Isotropic(Isotropic)
 }
 
 impl Default for Material {
     fn default() -> Self {
-        Material::Lambertian(Lambertian::from(Color::default()))
+        Material::solid(0.8, 0.8, 0.8)
+    }
+}
+
+impl Material {
+    pub fn solid(r: f64, g: f64, b: f64) -> Self {
+        Material::Lambertian(Lambertian::from(Color::new(r, g, b)))
+    }
+    pub fn light(r: f64, g: f64, b: f64) -> Self {
+        Material::DiffuseLight(DiffuseLight::from(Color::new(r, g, b)))
+    }
+    pub fn white_light(brightness: f64) -> Self {
+        Material::DiffuseLight(DiffuseLight::from(Color::new(brightness, brightness, brightness)))
     }
 }
 
@@ -28,7 +42,8 @@ impl Scatterable for Material {
             Material::Lambertian(l) => l.scatter(ray, hit_record),
             Material::Metal(m) => m.scatter(ray, hit_record),
             Material::Dielectric(d) => d.scatter(ray, hit_record),
-            Material::DiffuseLight(l) => l.scatter(ray, hit_record)
+            Material::DiffuseLight(l) => l.scatter(ray, hit_record),
+            Material::Isotropic(i) => i.scatter(ray, hit_record)
         }
     }
     fn emitted(&self, u: f64, v: f64, point: &Point3) -> Color {

src/obj.rs

@@ -0,0 +1,51 @@
+use std::path::Path;
+use std::sync::Arc;
+use tobj::LoadOptions;
+use crate::{BVH, Color, Dielectric, HittableList, HittableObject, Lambertian, Material, Point3, Vec3};
+use crate::hittable::Hittable;
+use crate::triangle::Triangle;
+
+pub fn obj_to_hitable(path: &Path) -> HittableObject {
+    let mut lo = LoadOptions::default();
+    lo.triangulate = true;
+    let (models, materials) = tobj::load_obj(path, &lo)
+        .unwrap();
+
+    let default_mat: Arc<Material> = Arc::new(
+        Material::Dielectric(
+            Dielectric::new(1.5)
+        )
+    );
+    let mut triangles: HittableList = Vec::with_capacity(models.len());
+    for model in models {
+        let mesh = model.mesh;
+        for f in 0..mesh.indices.len() / 3 {
+            let i0 = mesh.indices[3 * f] as usize;
+            let i1 = mesh.indices[3 * f + 1] as usize;
+            let i2 = mesh.indices[3 * f + 2] as usize;
+            let v0 = Point3::new(
+                mesh.positions[i0 * 3] as f64,
+                mesh.positions[i0 * 3 + 1] as f64,
+                mesh.positions[i0 * 3 + 2] as f64);
+            let v1 = Point3::new(
+                mesh.positions[i1 * 3] as f64,
+                mesh.positions[i1 * 3 + 1] as f64,
+                mesh.positions[i1 * 3 + 2] as f64);
+            let v2 = Point3::new(
+                mesh.positions[i2 * 3] as f64,
+                mesh.positions[i2 * 3 + 1] as f64,
+                mesh.positions[i2 * 3 + 2] as f64);
+            let triangle = if mesh.normals.len() <= i0 * 3 + 2 {
+                Triangle::without_normal(v0, v1, v2, default_mat.clone())
+            } else {
+                let normal = Vec3::new(
+                    mesh.normals[i0 * 3] as f64,
+                    mesh.normals[i0 * 3 + 1] as f64,
+                    mesh.normals[i0 * 3 + 2] as f64);
+                Triangle::new(v0, v1, v2, normal, default_mat.clone())
+            };
+            triangles.push(Arc::new(triangle));
+        }
+    }
+    Arc::new(BVH::new(triangles, 0.0, 1.0))
+}

src/translate.rs

@@ -18,31 +18,17 @@ impl<H: Hittable> Hittable for Translate<H> {
             ray.origin() - self.offset,
             ray.direction(),
             ray.time());
-        match &self.hittable.hit(&moved_ray, t_min, t_max) {
-            Some(hit_record) => {
-                let mut hr = HitRecord {
-                    point: hit_record.point,
-                    material: hit_record.material,
-                    front_face: hit_record.front_face, // Maybe need to calc normal and front_face again?
-                    normal: hit_record.normal,
-                    t: hit_record.t,
-                    u: hit_record.u,
-                    v: hit_record.v
-                };
-                hr.normalized(ray);
-                Some(hr)
-            }
-            _ => None
-        }
+        self.hittable.hit(&moved_ray, t_min, t_max).map(|mut hr| {
+            hr.point += self.offset;
+            hr
+        })
     }
 
     fn bounding_box(&self, time0: f64, time1: f64) -> Option<Aabb> {
-        match &self.hittable.bounding_box(time0, time1) {
-            Some(bounding_box) => Some(Aabb {
-                minimum: bounding_box.minimum + self.offset,
-                maximum: bounding_box.maximum + self.offset,
-            }),
-            _ => None
-        }
+        self.hittable.bounding_box(time0, time1).map(|mut b| {
+            b.minimum += self.offset;
+            b.maximum += self.offset;
+            b
+        })
     }
 }

src/triangle.rs

@@ -0,0 +1,78 @@
+use std::sync::Arc;
+use crate::hittable::{HitRecord, Hittable};
+use crate::{Aabb, Material, Point3, Ray, Vec3};
+//https://github.com/perliedman/raytracing-in-one-weekend/blob/master/src/geometry/triangle.rs
+
+pub struct Triangle {
+    a: Point3,
+    b: Point3,
+    c: Point3,
+    normal: Vec3,
+    material: Arc<Material>,
+}
+
+impl Triangle {
+    pub fn new(a: Point3, b: Point3, c: Point3, normal: Vec3, material: Arc<Material>, ) -> Self {
+        Self { a, b, c, normal, material  }
+    }
+    pub fn without_normal(a: Point3, b: Point3, c: Point3, material: Arc<Material>, ) -> Self {
+        let normal = (b - a).cross(&(c - a));
+        Self { a, b, c, normal, material  }
+    }
+}
+
+impl Hittable for Triangle {
+    fn hit(&self, ray: &Ray, t_min: f64, t_max: f64) -> Option<HitRecord> {
+        let ab = self.b - self.a;
+        let ac = self.c - self.a;
+        let pvec = ray.direction().cross(&ac);
+        let det = ab.dot(&pvec);
+        if det.abs() < 1e-4 {
+            return None;
+        }
+        let inv_det = 1.0 / det;
+        let tvec = ray.origin() - self.a;
+        let u = tvec.dot(&pvec) * inv_det;
+        if u < 0.0 || u > 1.0 {
+            return None;
+        }
+
+        let qvec = tvec.cross(&ab);
+        let v = ray.direction().dot(&qvec) * inv_det;
+        if v < 0.0 || u + v > 1.0 {
+            return None;
+        }
+
+        match ac.dot(&qvec) * inv_det {
+            t if t < t_min || t > t_max => None,
+            t => {
+                let mut rec = HitRecord {
+                    point: ray.at(t),
+                    normal: self.normal,
+                    t,
+                    u,
+                    v,
+                    front_face: true,
+                    material: &self.material
+                };
+                rec.normalized(ray);
+                Some(rec)
+            }
+        }
+    }
+
+    fn bounding_box(&self, _time0: f64, _time1: f64) -> Option<Aabb> {
+        Some(Aabb {
+            minimum: Point3::new(
+                self.a.x().min(self.b.x()).min(self.c.x()),
+                self.a.y().min(self.b.y()).min(self.c.y()),
+                self.a.z().min(self.b.z()).min(self.c.z()),
+            ),
+            maximum: Point3::new(
+                self.a.x().max(self.b.x()).max(self.c.x()),
+                self.a.y().max(self.b.y()).max(self.c.y()),
+                self.a.z().max(self.b.z()).max(self.c.z()),
+            ),
+        })
+    }
+}