ft (wip): random scene generation

src/camera.rs

@@ -1,6 +1,6 @@
 use std::f32::consts::PI;
 
-use log::{info, warn};
+use log::info;
 
 use crate::{
     objects::{hit::Hit, traits::Hittable},
@@ -129,7 +129,6 @@ impl Camera {
         if self.dirty {
             self.init()
         }
-        warn!("{}", format!("{self:#?}"));
 
         let mut imgbuf = image::ImageBuffer::new(self.image_width, self.image_height);
 

src/main.rs

@@ -10,39 +10,109 @@ use std::sync::Arc;
 use crate::camera::Camera;
 use crate::objects::materials::dielectric::Dielectric;
 use crate::objects::materials::lambertian::{Lambertian, Metal};
+use crate::objects::materials::traits::Material;
 use crate::objects::sphere::Sphere;
+use crate::objects::traits::Hittable;
 use crate::ray::Ray;
 use crate::vec3::Vec3;
 use dotenv::dotenv;
+use log::info;
 use pretty_env_logger;
+use rand::seq::IndexedRandom;
+use rand::RngExt;
+
+fn random_material() -> Arc<dyn Material> {
+    let mut rng = rand::rng();
+    let col = Vec3::new(rng.random(), rng.random(), rng.random());
+    match rng.random_range(0..3) {
+        0 => Arc::new(Lambertian::new(col, 1.)),
+        1 => Arc::new(Metal::new(col, 1., rng.random())),
+        2 => Arc::new(Dielectric::new(rng.random_range(0.3..1.9))),
+        _ => Arc::new(Metal::new(col, 0., rng.random())),
+    }
+}
+
+fn random_sphere_on_floor<T: Hittable>(
+    materials: &Vec<Arc<dyn Material>>,
+    existing: &Vec<T>,
+    max_size: f32,
+) -> Sphere {
+    let mut rng = rand::rng();
+    let r = rng.random_range(0.1..max_size);
+    let mut sphere = Sphere::xyz(
+        rng.random_range((-50.)..50.),
+        r,
+        rng.random_range((-50.)..50.),
+        r,
+        materials.choose(&mut rng).unwrap().clone(),
+    );
+
+    let mut isct = true;
+    let mut attempts_left = 49;
+    while isct && attempts_left > 0 {
+        isct = false;
+        for h in existing {
+            if h.inside(&h.closest_on_surface(sphere.center())) {
+                info!("Generating sphere failed, {} attempts left", attempts_left);
+                isct = true;
+                continue;
+            }
+        }
+        if isct {
+            sphere.set_center(Vec3::new(
+                rng.random_range(0.5..100.),
+                r,
+                rng.random_range(0.5..100.),
+            ));
+        }
+        attempts_left -= 1;
+    }
+    sphere
+}
 
 fn main() {
     dotenv().ok();
     pretty_env_logger::init();
 
     // setup objects
-    let blue = Arc::new(Metal::rgb(0.2, 0.4, 0.8, 1., 0.1));
-    let metal = Arc::new(Metal::rgb(0.7, 0.4, 0.2, 1., 0.1));
-    let ground = Arc::new(Lambertian::rgb(0.8, 0.8, 0., 1.0));
-    let center = Arc::new(Lambertian::rgb(0.1, 0.2, 0.5, 1.));
-    let left = Arc::new(Dielectric::new(1.5));
-    let bubble = Arc::new(Dielectric::new(1. / 1.5));
-    let right = Arc::new(Metal::rgb(0.8, 0.6, 0.2, 1., 1.0));
+    // let blue = Arc::new(Metal::rgb(0.2, 0.4, 0.8, 1., 0.1));
+    // let metal = Arc::new(Metal::rgb(0.7, 0.4, 0.2, 1., 0.1));
+    // let ground = Arc::new(Lambertian::rgb(0.8, 0.8, 0., 1.0));
+    // let center = Arc::new(Lambertian::rgb(0.1, 0.2, 0.5, 1.));
+    // let left = Arc::new(Dielectric::new(1.5));
+    // let bubble = Arc::new(Dielectric::new(1. / 1.5));
+    // let right = Arc::new(Metal::rgb(0.8, 0.6, 0.2, 1., 1.0));
+    //
+    // let mut world = vec![Sphere::xyz(0., 0.5, -0.8, 0.1, metal.clone())];
+    // world.push(Sphere::xyz(0., -100.5, -1., 100., ground.clone()));
+    // world.push(Sphere::xyz(0., 0., -1.2, 0.5, center.clone()));
+    // world.push(Sphere::xyz(-1., 0., -1.0, 0.5, left.clone()));
+    // world.push(Sphere::xyz(-1., 0., -1.0, 0.4, bubble.clone()));
+    // world.push(Sphere::xyz(1., 0., -1.0, 0.5, right.clone()));
+    // world.push(Sphere::xyz(0., 0.7, -0.4, 0.2, blue.clone()));
 
-    let mut world = vec![Sphere::xyz(0., 0.5, -0.8, 0.1, metal.clone())];
-    world.push(Sphere::xyz(0., -100.5, -1., 100., ground.clone()));
-    world.push(Sphere::xyz(0., 0., -1.2, 0.5, center.clone()));
-    world.push(Sphere::xyz(-1., 0., -1.0, 0.5, left.clone()));
-    world.push(Sphere::xyz(-1., 0., -1.0, 0.4, bubble.clone()));
-    world.push(Sphere::xyz(1., 0., -1.0, 0.5, right.clone()));
-    world.push(Sphere::xyz(0., 0.7, -0.4, 0.2, blue.clone()));
+    let mut materials: Vec<Arc<dyn Material>> = vec![Arc::new(Lambertian::rgb(0.1, 0.2, 0.6, 1.))];
+    for i in 0..15 {
+        info!("Generating {}th material.", i + 1);
+        materials.push(random_material());
+    }
 
-    let mut c = Camera::new(400, 300);
-    // let mut c = Camera::new(1920, 1080);
-    c.set_fov(20.);
-    c.set_anti_alias_rate(2);
-    c.set_max_depth(90);
-    c.set_look_from(Vec3::new(-2., 2., 1.));
-    c.set_look_at(Vec3::new(0., 0., -1.));
+    let mut world = vec![Sphere::xyz(0., -1000.5, -1., 1000., materials[0].clone())];
+    for i in 0..40 {
+        info!("Generating {}th sphere.", i + 1);
+        world.push(random_sphere_on_floor(
+            &materials,
+            &world,
+            (i + 1) as f32 / 3.,
+        ));
+    }
+
+    // let mut c = Camera::new(400, 300);
+    let mut c = Camera::new(1920, 1080);
+    c.set_fov(90.);
+    c.set_anti_alias_rate(6);
+    c.set_max_depth(100);
+    c.set_look_from(Vec3::new(-60., 10., 1.));
+    c.set_look_at(Vec3::new(0., 0., 0.));
     c.render(&world);
 }

src/objects/sphere.rs

@@ -29,6 +29,16 @@ impl Sphere {
             material: mat,
         }
     }
+
+    pub fn center(&self) -> &Vec3 {
+        &self.center
+    }
+
+    pub fn set_center(&mut self, center: Vec3) {
+        if self.center != center {
+            self.center = center;
+        }
+    }
 }
 
 impl Hittable for Sphere {
@@ -60,4 +70,12 @@ impl Hittable for Sphere {
     fn normal_at(&self, p: &Vec3) -> Vec3 {
         (*p - self.center).get_unit()
     }
+
+    fn inside(&self, p: &Vec3) -> bool {
+        (*p - self.center).length() < self.radius
+    }
+
+    fn closest_on_surface(&self, p: &Vec3) -> Vec3 {
+        self.normal_at(p) * self.radius
+    }
 }

src/objects/traits.rs

@@ -5,4 +5,7 @@ use crate::Vec3;
 pub trait Hittable {
     fn hit(&self, r: &Ray) -> Option<Hit>;
     fn normal_at(&self, p: &Vec3) -> Vec3;
+    // fn intersect<H: Hittable>(&self, o: &H) -> bool;
+    fn inside(&self, p: &Vec3) -> bool;
+    fn closest_on_surface(&self, p: &Vec3) -> Vec3;
 }