Add cornell_flips with the flipped faces just in case. Refer to RayTr…

…acing/raytracing.github.io#602

src/main.rs

@@ -29,7 +29,7 @@ use color::Color;
 use hitable::{BVHNode, HitRecord, Hitable};
 #[allow(unused)] // Scene imports, only using one at a time
 use scenes::{
-    cornell, glass_spheres, metal_spheres, random_scene, simple_light_lambertian,
+    cornell, cornell_flips, glass_spheres, metal_spheres, random_scene, simple_light_lambertian,
     simple_light_perlin, two_perlin_spheres, two_spheres,
 };
 mod perlin;

src/material.rs

@@ -39,12 +39,20 @@ pub struct Lambertian {
 
 impl Material for Lambertian {
     fn scatter(&self, ray: &Ray, hit_record: &HitRecord, rng: ThreadRng) -> Option<(Ray, Color)> {
-        let target = hit_record.position + hit_record.normal + random_unit_vector(rng);
-        let scattered: Ray = Ray::new(hit_record.position, target - hit_record.position, ray.time);
-        let attenuation: Color = self
+        let scatter_direction: Vec3 = hit_record.normal + random_unit_vector(rng);
+        let scattered = Ray::new(hit_record.position, scatter_direction, ray.time);
+        let attenuation = self
             .albedo
             .color(hit_record.u, hit_record.v, hit_record.position);
         Some((scattered, attenuation))
+
+        // old backup
+        //     let target = hit_record.position + hit_record.normal + random_unit_vector(rng);
+        //     let scattered: Ray = Ray::new(hit_record.position, target - hit_record.position, ray.time);
+        //     let attenuation: Color = self
+        //         .albedo
+        //         .color(hit_record.u, hit_record.v, hit_record.position);
+        //     Some((scattered, attenuation))
     }
 }
 

src/scenes.rs

@@ -7,6 +7,7 @@ use crate::{
 use rand::prelude::*;
 
 pub mod cornell;
+pub mod cornell_flips;
 pub mod glass_spheres;
 pub mod metal_spheres;
 pub mod random_scene;

src/scenes/cornell_flips.rs

@@ -0,0 +1,102 @@
+use super::Scene;
+use crate::{
+    camera::Camera,
+    color::Color,
+    hitable::{FlipFace, HitableList},
+    material::{DiffuseLight, Lambertian, Material},
+    rect::{XYRect, XZRect, YZRect},
+    texture::SolidColor,
+    Float, Vec3, HEIGHT, WIDTH,
+};
+use rand::prelude::*;
+use std::sync::Arc;
+
+pub fn load(rng: ThreadRng) -> Scene {
+    let time_0: Float = 0.0;
+    let time_1: Float = 1.0;
+    let mut world: HitableList = HitableList::new();
+
+    let red = Lambertian::new(Arc::new(SolidColor::new(Color::new(0.65, 0.05, 0.05))));
+    let white: Arc<dyn Material> = Arc::new(Lambertian::new(Arc::new(SolidColor::new(
+        Color::new(0.73, 0.73, 0.73),
+    ))));
+    let green = Lambertian::new(Arc::new(SolidColor::new(Color::new(0.12, 0.45, 0.15))));
+    let light = DiffuseLight::new(Arc::new(SolidColor::new(Color::new(15.0, 15.0, 15.0))));
+
+    world
+        .hitables
+        .push(Arc::new(FlipFace::new(Arc::new(YZRect::new(
+            0.0,
+            555.0,
+            0.0,
+            555.0,
+            555.0,
+            Arc::new(green),
+        )))));
+    world.hitables.push(Arc::new(YZRect::new(
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        0.0,
+        Arc::new(red),
+    )));
+    world.hitables.push(Arc::new(XZRect::new(
+        213.0,
+        343.0,
+        227.0,
+        332.0,
+        554.0,
+        Arc::new(light),
+    )));
+    world
+        .hitables
+        .push(Arc::new(FlipFace::new(Arc::new(XZRect::new(
+            0.0,
+            555.0,
+            0.0,
+            555.0,
+            0.0,
+            Arc::clone(&white),
+        )))));
+    world.hitables.push(Arc::new(XZRect::new(
+        0.0,
+        555.0,
+        0.0,
+        555.0,
+        555.0,
+        Arc::clone(&white),
+    )));
+    world
+        .hitables
+        .push(Arc::new(FlipFace::new(Arc::new(XYRect::new(
+            0.0,
+            555.0,
+            0.0,
+            555.0,
+            555.0,
+            Arc::clone(&white),
+        )))));
+
+    let camera_position: Vec3 = Vec3::new(278.0, 278.0, -800.0);
+    let camera_target: Vec3 = Vec3::new(278.0, 278.0, 0.0);
+    let camera_up: Vec3 = Vec3::new(0.0, 1.0, 0.0);
+    let fov: Float = 40.0;
+    let aspect_ratio: Float = WIDTH as Float / HEIGHT as Float;
+    let aperture: Float = 0.0;
+    let focus_distance: Float = 10.0;
+    let camera = Camera::new(
+        camera_position,
+        camera_target,
+        camera_up,
+        fov,
+        aspect_ratio,
+        aperture,
+        focus_distance,
+        time_0,
+        time_1,
+    );
+
+    let background: Color = Color::new(0.0, 0.0, 0.0); // Black background = only lit by the light, no ambient
+    Scene::new(world, camera, time_0, time_1, background, rng)
+}