pathtracer: move rendering logic to 'render' module

pathtracer/src/lib.rs

@@ -11,6 +11,7 @@ pub type Point2D = nalgebra::Point2<f32>;
 pub mod core;
 pub mod light;
 pub mod material;
+pub mod render;
 pub mod scene;
 pub mod serialize;
 pub mod shape;

pathtracer/src/main.rs

@@ -1,3 +1,4 @@
+use pathtracer::render::Raytracer;
 use pathtracer::scene::Scene;
 use std::path::PathBuf;
 use structopt::StructOpt;
@@ -17,7 +18,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let f = std::fs::File::open(options.input)?;
 
     let scene: Scene = serde_yaml::from_reader(f)?;
-    let image = scene.render();
+    let image = Raytracer::new(scene).render();
 
     image.save(options.output)?;
     Ok(())

pathtracer/src/render/mod.rs

@@ -0,0 +1,6 @@
+//! Define the different kinds of renderers for use on a given scene.
+
+mod raytracer;
+pub use raytracer::*;
+
+pub(crate) mod utils;

pathtracer/src/render/raytracer.rs

@@ -0,0 +1,249 @@
+use super::utils::*;
+use crate::scene::{Object, Scene};
+use crate::{
+    core::{LightProperties, LinearColor, ReflTransEnum},
+    material::Material,
+    shape::Shape,
+    texture::Texture,
+    {Point, Vector},
+};
+use beevee::ray::Ray;
+use image::RgbImage;
+use nalgebra::Unit;
+use rand::prelude::thread_rng;
+use rand::Rng;
+
+/// Render the [`Scene`] using Raytracing.
+///
+/// [`Scene`]: ../scene/scene/struct.Scene.html
+pub struct Raytracer {
+    scene: Scene,
+}
+
+impl Raytracer {
+    /// Create a [`Raytracer`] renderer with the given [`Scene`]
+    ///
+    /// [`Raytracer`]: struct.Raytracer.html
+    /// [`Scene`]: ../scene/scene/struct.Scene.html
+    pub fn new(scene: Scene) -> Self {
+        Raytracer { scene }
+    }
+
+    /// Render the [`Scene`] using Raytracing.
+    ///
+    /// [`Scene`]: ../scene/scene/struct.Scene.html
+    pub fn render(&self) -> RgbImage {
+        let mut image = RgbImage::new(
+            self.scene.camera.film().width(),
+            self.scene.camera.film().height(),
+        );
+
+        let total = (image.width() * image.height()) as u64;
+        let pb = indicatif::ProgressBar::new(total);
+        pb.set_draw_delta(total / 10000);
+        pb.set_style(indicatif::ProgressStyle::default_bar().template(
+            "{spinner:.green} [{elapsed_precise}] [{wide_bar:.cyan/blue}] {percent:>3}%: {pos}/{len} pixels (ETA: {eta})",
+        ));
+
+        let pixel_func = if self.scene.aliasing_limit > 0 {
+            Self::anti_alias_pixel
+        } else {
+            Self::pixel
+        };
+
+        rayon::scope(|s| {
+            // FIXME(Bruno): it would go even faster to cut the image in blocks of rows, leading to
+            // better cache-line behaviour...
+            for (_, row) in image.enumerate_rows_mut() {
+                s.spawn(|_| {
+                    for (x, y, pixel) in row {
+                        *pixel = pixel_func(&self, x as f32, y as f32).into();
+                        pb.inc(1);
+                    }
+                })
+            }
+        });
+
+        pb.finish();
+        image
+    }
+
+    /// Get pixel color for (x, y) a pixel **coordinate**
+    fn pixel(&self, x: f32, y: f32) -> LinearColor {
+        let (x, y) = self.scene.camera.film().pixel_ratio(x, y);
+        let indices = RefractionInfo::with_index(self.scene.diffraction_index);
+        let ray = self.scene.camera.ray_with_ratio(x, y);
+        self.cast_ray(ray).map_or_else(
+            || self.scene.background.clone(),
+            |(t, obj)| {
+                self.color_at(
+                    ray.origin + ray.direction.as_ref() * t,
+                    obj,
+                    ray.direction,
+                    self.scene.reflection_limit,
+                    indices,
+                )
+            },
+        )
+    }
+
+    /// Get pixel color with anti-aliasing
+    fn anti_alias_pixel(&self, x: f32, y: f32) -> LinearColor {
+        let range = 0..self.scene.aliasing_limit;
+        let mut rng = thread_rng();
+        let acc: LinearColor = range
+            .map(|_| {
+                let random_x: f32 = rng.gen();
+                let random_y: f32 = rng.gen();
+                self.pixel(x + random_x, y + random_y)
+            })
+            .map(LinearColor::clamp)
+            .sum();
+        acc / self.scene.aliasing_limit as f32
+    }
+
+    fn cast_ray(&self, ray: Ray) -> Option<(f32, &Object)> {
+        self.scene.bvh.walk(&ray, &self.scene.objects)
+    }
+
+    fn color_at(
+        &self,
+        point: Point,
+        object: &Object,
+        incident_ray: Unit<Vector>,
+        reflection_limit: u32,
+        mut indices: RefractionInfo,
+    ) -> LinearColor {
+        let texel = object.shape.project_texel(&point);
+        let properties = object.material.properties(texel);
+        let object_color = object.texture.texel_color(texel);
+
+        let normal = object.shape.normal(&point);
+        let reflected_ray = reflected(incident_ray, normal);
+
+        // FIXME: change this to averaged sampled rays instead of visiting every light ?
+        // Indeed the path-tracing algorithm is good for calculating the radiance at a point
+        // But it should be used for reflection and refraction too...
+        let lighting = self.illuminate(point, object_color, &properties, normal, reflected_ray);
+        if properties.refl_trans.is_none() {
+            // Avoid calculating reflection when not needed
+            return lighting;
+        }
+        let reflected = self.reflection(point, reflected_ray, reflection_limit, indices.clone());
+        // We can unwrap safely thanks to the check for None before
+        match properties.refl_trans.unwrap() {
+            ReflTransEnum::Transparency { coef, index } => {
+                // Calculate the refracted ray, if it was refracted, and mutate indices accordingly
+                refracted(incident_ray, normal, &mut indices, index).map_or_else(
+                    // Total reflection
+                    || reflected.clone(),
+                    // Refraction (refracted ray, amount of *reflection*)
+                    |(r, refl_t)| {
+                        let refracted = self.refraction(point, coef, r, reflection_limit, indices);
+                        let refr_light = refracted * (1. - refl_t) + reflected.clone() * refl_t;
+                        refr_light * coef + lighting * (1. - coef)
+                    },
+                )
+            }
+            ReflTransEnum::Reflectivity { coef } => reflected * coef + lighting * (1. - coef),
+        }
+    }
+
+    fn refraction(
+        &self,
+        point: Point,
+        transparency: f32,
+        refracted: Unit<Vector>,
+        reflection_limit: u32,
+        indices: RefractionInfo,
+    ) -> LinearColor {
+        if transparency > 1e-5 && reflection_limit > 0 {
+            let refraction_start = point + refracted.as_ref() * 0.001;
+            if let Some((t, obj)) = self.cast_ray(Ray::new(refraction_start, refracted)) {
+                let resulting_position = refraction_start + refracted.as_ref() * t;
+                let refracted = self.color_at(
+                    resulting_position,
+                    obj,
+                    refracted,
+                    reflection_limit - 1,
+                    indices,
+                );
+                return refracted * transparency;
+            }
+        }
+        LinearColor::black()
+    }
+
+    fn reflection(
+        &self,
+        point: Point,
+        reflected: Unit<Vector>,
+        reflection_limit: u32,
+        indices: RefractionInfo,
+    ) -> LinearColor {
+        if reflection_limit > 0 {
+            let reflection_start = point + reflected.as_ref() * 0.001;
+            if let Some((t, obj)) = self.cast_ray(Ray::new(reflection_start, reflected)) {
+                let resulting_position = reflection_start + reflected.as_ref() * t;
+                let color = self.color_at(
+                    resulting_position,
+                    obj,
+                    reflected,
+                    reflection_limit - 1,
+                    indices,
+                );
+                return color;
+            }
+        };
+        LinearColor::black()
+    }
+
+    fn illuminate(
+        &self,
+        point: Point,
+        object_color: LinearColor,
+        properties: &LightProperties,
+        normal: Unit<Vector>,
+        reflected: Unit<Vector>,
+    ) -> LinearColor {
+        let ambient = self.illuminate_ambient(object_color.clone());
+        let spatial = self.illuminate_spatial(point, properties, normal, reflected);
+        ambient + object_color * spatial
+    }
+
+    fn illuminate_ambient(&self, color: LinearColor) -> LinearColor {
+        self.scene
+            .lights
+            .ambient_lights_iter()
+            .map(|light| color.clone() * light.illumination(&Point::origin()))
+            .map(LinearColor::clamp)
+            .sum()
+    }
+
+    fn illuminate_spatial(
+        &self,
+        point: Point,
+        properties: &LightProperties,
+        normal: Unit<Vector>,
+        reflected: Unit<Vector>,
+    ) -> LinearColor {
+        self.scene
+            .lights
+            .spatial_lights_iter()
+            .map(|light| {
+                let (direction, t) = light.to_source(&point);
+                let light_ray = Ray::new(point + direction.as_ref() * 0.001, direction);
+                match self.cast_ray(light_ray) {
+                    // Take shadows into account
+                    Some((obstacle_t, _)) if obstacle_t < t => return LinearColor::black(),
+                    _ => {}
+                }
+                let lum = light.illumination(&point);
+                let diffused = properties.diffuse.clone() * normal.dot(&direction);
+                let specular = properties.specular.clone() * reflected.dot(&direction);
+                lum * (diffused + specular)
+            })
+            .map(LinearColor::clamp)
+            .sum()
+    }
+}

pathtracer/src/scene/mod.rs

@@ -1,4 +1,4 @@
-//! Rendering logic
+//! Desciption of the scene.
 
 pub mod light_aggregate;
 pub use light_aggregate::*;
@@ -11,5 +11,3 @@ pub use object::*;
 
 pub mod scene;
 pub use scene::*;
-
-pub(crate) mod utils;

pathtracer/src/scene/scene.rs

@@ -1,32 +1,22 @@
-//! Scene rendering logic
+//! Scene representation.
 
-use super::{light_aggregate::LightAggregate, mesh::Mesh, object::Object, utils::*};
+use super::{LightAggregate, Mesh, Object};
-use crate::{
+use crate::core::{Camera, LinearColor};
-    core::{Camera, LightProperties, LinearColor, ReflTransEnum},
+use beevee::bvh::BVH;
-    material::Material,
-    shape::Shape,
-    texture::Texture,
-    {Point, Vector},
-};
-use beevee::{bvh::BVH, ray::Ray};
-use image::RgbImage;
-use nalgebra::Unit;
-use rand::prelude::thread_rng;
-use rand::Rng;
 use serde::Deserialize;
 
 /// Represent the scene being rendered.
 #[serde(from = "SerializedScene")]
 #[derive(Debug, PartialEq, Deserialize)]
 pub struct Scene {
-    camera: Camera,
+    pub(crate) camera: Camera,
-    lights: LightAggregate,
+    pub(crate) lights: LightAggregate,
-    objects: Vec<Object>,
+    pub(crate) objects: Vec<Object>,
-    bvh: BVH,
+    pub(crate) bvh: BVH,
-    background: LinearColor,
+    pub(crate) background: LinearColor,
-    aliasing_limit: u32,
+    pub(crate) aliasing_limit: u32,
-    reflection_limit: u32,
+    pub(crate) reflection_limit: u32,
-    diffraction_index: f32,
+    pub(crate) diffraction_index: f32,
 }
 
 impl Scene {
@@ -85,217 +75,6 @@ impl Scene {
             diffraction_index,
         }
     }
-
-    /// Render the scene into an image.
-    pub fn render(&self) -> RgbImage {
-        let mut image = RgbImage::new(self.camera.film().width(), self.camera.film().height());
-
-        let total = (image.width() * image.height()) as u64;
-        let pb = indicatif::ProgressBar::new(total);
-        pb.set_draw_delta(total / 10000);
-        pb.set_style(indicatif::ProgressStyle::default_bar().template(
-            "{spinner:.green} [{elapsed_precise}] [{wide_bar:.cyan/blue}] {percent:>3}%: {pos}/{len} pixels (ETA: {eta})",
-        ));
-
-        let pixel_func = if self.aliasing_limit > 0 {
-            Self::anti_alias_pixel
-        } else {
-            Self::pixel
-        };
-
-        rayon::scope(|s| {
-            // FIXME(Bruno): it would go even faster to cut the image in blocks of rows, leading to
-            // better cache-line behaviour...
-            for (_, row) in image.enumerate_rows_mut() {
-                s.spawn(|_| {
-                    for (x, y, pixel) in row {
-                        *pixel = pixel_func(&self, x as f32, y as f32).into();
-                        pb.inc(1);
-                    }
-                })
-            }
-        });
-
-        pb.finish();
-        image
-    }
-
-    /// Get pixel color for (x, y) a pixel **coordinate**
-    fn pixel(&self, x: f32, y: f32) -> LinearColor {
-        let (x, y) = self.camera.film().pixel_ratio(x, y);
-        let indices = RefractionInfo::with_index(self.diffraction_index);
-        let ray = self.camera.ray_with_ratio(x, y);
-        self.cast_ray(ray).map_or_else(
-            || self.background.clone(),
-            |(t, obj)| {
-                self.color_at(
-                    ray.origin + ray.direction.as_ref() * t,
-                    obj,
-                    ray.direction,
-                    self.reflection_limit,
-                    indices,
-                )
-            },
-        )
-    }
-
-    /// Get pixel color with anti-aliasing
-    fn anti_alias_pixel(&self, x: f32, y: f32) -> LinearColor {
-        let range = 0..self.aliasing_limit;
-        let mut rng = thread_rng();
-        let acc: LinearColor = range
-            .map(|_| {
-                let random_x: f32 = rng.gen();
-                let random_y: f32 = rng.gen();
-                self.pixel(x + random_x, y + random_y)
-            })
-            .map(LinearColor::clamp)
-            .sum();
-        acc / self.aliasing_limit as f32
-    }
-
-    fn cast_ray(&self, ray: Ray) -> Option<(f32, &Object)> {
-        self.bvh.walk(&ray, &self.objects)
-    }
-
-    fn color_at(
-        &self,
-        point: Point,
-        object: &Object,
-        incident_ray: Unit<Vector>,
-        reflection_limit: u32,
-        mut indices: RefractionInfo,
-    ) -> LinearColor {
-        let texel = object.shape.project_texel(&point);
-        let properties = object.material.properties(texel);
-        let object_color = object.texture.texel_color(texel);
-
-        let normal = object.shape.normal(&point);
-        let reflected_ray = reflected(incident_ray, normal);
-
-        // FIXME: change this to averaged sampled rays instead of visiting every light ?
-        // Indeed the path-tracing algorithm is good for calculating the radiance at a point
-        // But it should be used for reflection and refraction too...
-        let lighting = self.illuminate(point, object_color, &properties, normal, reflected_ray);
-        if properties.refl_trans.is_none() {
-            // Avoid calculating reflection when not needed
-            return lighting;
-        }
-        let reflected = self.reflection(point, reflected_ray, reflection_limit, indices.clone());
-        // We can unwrap safely thanks to the check for None before
-        match properties.refl_trans.unwrap() {
-            ReflTransEnum::Transparency { coef, index } => {
-                // Calculate the refracted ray, if it was refracted, and mutate indices accordingly
-                refracted(incident_ray, normal, &mut indices, index).map_or_else(
-                    // Total reflection
-                    || reflected.clone(),
-                    // Refraction (refracted ray, amount of *reflection*)
-                    |(r, refl_t)| {
-                        let refracted = self.refraction(point, coef, r, reflection_limit, indices);
-                        let refr_light = refracted * (1. - refl_t) + reflected.clone() * refl_t;
-                        refr_light * coef + lighting * (1. - coef)
-                    },
-                )
-            }
-            ReflTransEnum::Reflectivity { coef } => reflected * coef + lighting * (1. - coef),
-        }
-    }
-
-    fn refraction(
-        &self,
-        point: Point,
-        transparency: f32,
-        refracted: Unit<Vector>,
-        reflection_limit: u32,
-        indices: RefractionInfo,
-    ) -> LinearColor {
-        if transparency > 1e-5 && reflection_limit > 0 {
-            let refraction_start = point + refracted.as_ref() * 0.001;
-            if let Some((t, obj)) = self.cast_ray(Ray::new(refraction_start, refracted)) {
-                let resulting_position = refraction_start + refracted.as_ref() * t;
-                let refracted = self.color_at(
-                    resulting_position,
-                    obj,
-                    refracted,
-                    reflection_limit - 1,
-                    indices,
-                );
-                return refracted * transparency;
-            }
-        }
-        LinearColor::black()
-    }
-
-    fn reflection(
-        &self,
-        point: Point,
-        reflected: Unit<Vector>,
-        reflection_limit: u32,
-        indices: RefractionInfo,
-    ) -> LinearColor {
-        if reflection_limit > 0 {
-            let reflection_start = point + reflected.as_ref() * 0.001;
-            if let Some((t, obj)) = self.cast_ray(Ray::new(reflection_start, reflected)) {
-                let resulting_position = reflection_start + reflected.as_ref() * t;
-                let color = self.color_at(
-                    resulting_position,
-                    obj,
-                    reflected,
-                    reflection_limit - 1,
-                    indices,
-                );
-                return color;
-            }
-        };
-        LinearColor::black()
-    }
-
-    fn illuminate(
-        &self,
-        point: Point,
-        object_color: LinearColor,
-        properties: &LightProperties,
-        normal: Unit<Vector>,
-        reflected: Unit<Vector>,
-    ) -> LinearColor {
-        let ambient = self.illuminate_ambient(object_color.clone());
-        let spatial = self.illuminate_spatial(point, properties, normal, reflected);
-        ambient + object_color * spatial
-    }
-
-    fn illuminate_ambient(&self, color: LinearColor) -> LinearColor {
-        self.lights
-            .ambient_lights_iter()
-            .map(|light| color.clone() * light.illumination(&Point::origin()))
-            .map(LinearColor::clamp)
-            .sum()
-    }
-
-    fn illuminate_spatial(
-        &self,
-        point: Point,
-        properties: &LightProperties,
-        normal: Unit<Vector>,
-        reflected: Unit<Vector>,
-    ) -> LinearColor {
-        self.lights
-            .spatial_lights_iter()
-            .map(|light| {
-                let (direction, t) = light.to_source(&point);
-                let light_ray = Ray::new(point + 0.001 * direction.as_ref(), direction);
-                match self.cast_ray(light_ray) {
-                    // Take shadows into account
-                    Some((obstacle_t, _)) if obstacle_t < t => return LinearColor::black(),
-                    _ => {}
-                }
-                let lum = light.illumination(&point);
-                let diffused = properties.diffuse.clone() * normal.dot(&direction);
-                let specular = properties.specular.clone() * reflected.dot(&direction);
-                lum * (diffused + specular)
-            })
-            .map(LinearColor::clamp)
-            .sum()
-    }
 }
 
 #[derive(Debug, PartialEq, Deserialize)]