added emitting material and 2nd example render

README.md

@@ -2,3 +2,4 @@
 ![Build](https://git.veltko.de/plexx-dev/raychel-rs/actions/workflows/build.yml/badge.svg?branch=main&event=push&style=flat-square)
 ### quick and dirty multithreaded raymarcher using the awesome [_Ray Tracing in One Weekend_](https://raytracing.github.io/books/RayTracingInOneWeekend.html) Book Series
 ![Example Scene](example.png)
+![Example Dark Scene](example_dark.png)

src/camera.rs

@@ -73,21 +73,24 @@ impl Camera {
         }
 
         if let Some(rec) = world.hit(&r, 0.001, f64::INFINITY) {
+            let emitted = rec.material.emitted();
             let mut scattered = Ray::new_empty();
             let mut attenuation = Color::new_empty();
 
             if rec
                 .material
-                .scatter(r, rec, &mut attenuation, &mut scattered)
+                .scatter(r, rec.clone(), &mut attenuation, &mut scattered)
             {
-                return attenuation * Self::ray_color(&self, scattered, world, depth - 1);
+                return emitted + attenuation * self.ray_color(scattered, world, depth - 1);
+            } else {
+                return emitted;
             }
-            return Color::new_empty();
         }
 
-        let unit_direction: Vec3 = r.direction().unit_vector();
-        let t = 0.5 * (unit_direction.y() + 1.0);
-
-        ((1.0 - t) * Color::new(1.0, 1.0, 1.0)) + (t * Color::new(0.5, 0.7, 1.0))
+        // Sky background
+        // let unit_direction: Vec3 = r.direction().unit_vector();
+        // let t = 0.5 * (unit_direction.y() + 1.0);
+        //((1.0 - t) * Color::new(1.0, 1.0, 1.0)) + (t * Color::new(0.5, 0.7, 1.0))
+        Color::new_empty()
     }
 }

src/color.rs

@@ -1,6 +1,8 @@
-use crate::{vec3::*, rtweekend::clamp};
+use image::Rgb;
 
-pub fn get_scaled_color_components(c: Color, samples_per_pixel: i32) -> (u8, u8, u8) {
+use crate::{rtweekend::clamp, vec3::*};
+
+pub fn get_scaled_color_components(c: Color, samples_per_pixel: i32) -> Rgb<u8> {
     let r = c.x();
     let g = c.y();
     let b = c.z();
@@ -11,9 +13,9 @@ pub fn get_scaled_color_components(c: Color, samples_per_pixel: i32) -> (u8, u8,
     let g = (scale * g).sqrt();
     let b = (scale * b).sqrt();
 
-    (
+    Rgb([
         (255.0 * clamp(r, 0.0, 1.0)) as u8,
         (255.0 * clamp(g, 0.0, 1.0)) as u8,
         (255.0 * clamp(b, 0.0, 1.0)) as u8,
-    )
-}
+    ])
+}

src/main.rs

@@ -10,7 +10,7 @@ pub mod vec3;
 
 use std::{f64, thread::available_parallelism};
 
-use image::{Pixel, RgbImage};
+use image::RgbImage;
 use indicatif::{ProgressBar, ProgressStyle};
 use rayon::prelude::*;
 
@@ -74,6 +74,13 @@ fn random_scene(aspect_ratio: f64) -> (Camera, HittableList) {
         }
     }
 
+    let material0  = Light::new(Color::new(15., 15., 15.));
+    world.add(Box::new(Sphere::new(
+        Point3::new(-1.0, 1.0, 0.0),
+        1.0,
+        Box::new(material0),
+    )));
+
     let material1: Dielectric = Dielectric::new(1.5);
     world.add(Box::new(Sphere::new(
         Point3::new(0.0, 1.0, 0.0),
@@ -159,15 +166,15 @@ fn three_balls_scene(aspect_ratio: f64) -> (Camera, HittableList) {
     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 = 10.0; //(lookfrom - lookat).length_squared();
-    let vfov = 20.0;
+    let dist_to_focus = (lookfrom - lookat).length();
+    let focal_length_mm = 20.0;
     let defocus_angle = 0.0;
 
     let cam = Camera::new(
         lookfrom,
         lookat,
         vup,
-        vfov,
+        focal_length_mm,
         aspect_ratio,
         defocus_angle,
         dist_to_focus,
@@ -181,10 +188,9 @@ fn main() {
     let aspect_ratio: f64 = 16. / 9.;
     let image_width: i32 = 1920;
     let image_height: i32 = (image_width as f64 / aspect_ratio as f64) as i32;
-    let samples_per_pixel: i32 = 200;
+    let samples_per_pixel: i32 = 400;
     let max_depth: i32 = 10;
 
-    // Camera and World
     let (cam, world) = random_scene(aspect_ratio);
 
     let num_threads: usize = match available_parallelism() {
@@ -226,11 +232,7 @@ fn main() {
                 pixel_color += cam.ray_color(r, &world, max_depth);
             }
 
-            let (ir, ig, ib) = get_scaled_color_components(pixel_color, samples_per_pixel);
-
-            pixel.channels_mut()[0] = ir;
-            pixel.channels_mut()[1] = ig;
-            pixel.channels_mut()[2] = ib;
+            *pixel = get_scaled_color_components(pixel_color, samples_per_pixel);
 
             bar.inc(1);
         });
@@ -239,6 +241,3 @@ fn main() {
 
     img_buffer.save("render.png").unwrap();
 }
-
-// print!("\r{} %", progress);
-// let _ = stdout().flush();

src/material.rs

@@ -16,6 +16,10 @@ use crate::vec3::{random_unit_vector, reflect, refract, Color};
 */
 
 pub trait Material: Send + Sync {
+    fn emitted(&self) -> Color {
+        Color::new(0.0, 0.0, 0.0)
+    }
+
     fn scatter(
         &self,
         r_in: Ray,
@@ -134,3 +138,29 @@ impl Material for Dielectric {
         true
     }
 }
+
+pub struct Light {
+    emit: Color
+}
+
+impl Light {
+    pub const fn new(emit: Color) -> Self {
+        Light { emit }
+    }
+}
+
+impl Material for Light {
+    fn scatter(
+        &self,
+        _r_in: Ray,
+        _rec: HitRecord,
+        _attenuation: &mut Color,
+        _scattered: &mut Ray,
+    ) -> bool {
+        false // Light sources dont scatter rays
+    }
+
+    fn emitted(&self) -> Color {
+        self.emit
+    }
+}