Numerous small changes suggested by clippy

src/accumulation_buffer.rs

@@ -47,7 +47,7 @@ impl AccumulationBuffer {
         let buffer_colour_bias = &mut self.colour_bias_buffer[row][column];
         let buffer_weight = &mut self.weight_buffer[row][column];
         let buffer_weight_bias = &mut self.weight_bias_buffer[row][column];
-        let photon_colour = ColourXyz::from_photon(&photon);
+        let photon_colour = ColourXyz::from_photon(photon);
         let weight_sum_y = weight - *buffer_weight_bias;
         let weight_sum_t = *buffer_weight + weight_sum_y;
         *buffer_weight_bias = (weight_sum_t - *buffer_weight) - weight_sum_y;

src/camera.rs

@@ -101,7 +101,7 @@ pub fn partial_render_scene(
     let mut output_image_tile = AccumulationBuffer::new(tile.width(), tile.height());
     let image_sampler = ImageSampler::new(width, height, scene.camera_location);
     let integrator = SimpleRandomIntegrator {};
-    let sampler = Sampler { scene: &scene };
+    let sampler = Sampler { scene };
     for column in 0..tile.width() {
         for row in 0..tile.height() {
             let ray = image_sampler.ray_for_pixel(tile.start_row + row, tile.start_column + column);

src/colour/photon.rs

@@ -37,7 +37,7 @@ impl Photon {
     pub fn set_intensity(&self, intensity: f64) -> Photon {
         Photon {
             wavelength: self.wavelength,
-            intensity: intensity,
+            intensity,
         }
     }
 }

src/image.rs

@@ -1,4 +1,3 @@
-use std::convert::TryInto;
 use std::fs::File;
 use std::io::BufWriter;
 use std::path::Path;
@@ -20,7 +19,7 @@ impl ImageRgbU8 {
 
     pub fn get_colour(&self, row: usize, column: usize) -> ColourRgbU8 {
         ColourRgbU8 {
-            values: self.data[row][column].try_into().expect("Wrong length."),
+            values: self.data[row][column],
         }
     }
 
@@ -52,7 +51,7 @@ impl ImageRgbU8 {
 
     pub fn write_png(&self, filename: &Path) -> Result<(), std::io::Error> {
         let file = File::create(filename)?;
-        let ref mut file_buffer = BufWriter::new(file);
+        let file_buffer = &mut BufWriter::new(file);
 
         let mut encoder = png::Encoder::new(
             file_buffer,

src/integrators/simple_random_integrator.rs

@@ -34,7 +34,7 @@ impl Integrator for SimpleRandomIntegrator {
         let MaterialSampleResult {
             direction: w_o,
             pdf: w_o_pdf,
-        } = info.material.sample(&w_i, &photon);
+        } = info.material.sample(&w_i, photon);
         let world_space_w_o = bsdf_to_world_space * w_o;
         info.material.bsdf()(
             &w_o,
@@ -45,7 +45,7 @@ impl Integrator for SimpleRandomIntegrator {
                     photon.wavelength,
                 )),
                 Some(recursive_hit) => {
-                    self.integrate(&sampler, &recursive_hit, &photon, recursion_limit - 1)
+                    self.integrate(sampler, &recursive_hit, photon, recursion_limit - 1)
                 }
             }
             .scale_intensity(w_o_pdf)

src/integrators/whitted_integrator.rs

@@ -35,13 +35,13 @@ impl Integrator for WhittedIntegrator {
             .iter()
             .map(|light| {
                 match sampler.sample(&Ray::new(info.location, light.direction).bias(0.000_000_1)) {
-                    Some(_) => self.ambient_light.emit_photon(&photon),
+                    Some(_) => self.ambient_light.emit_photon(photon),
                     None => info.material.bsdf()(
                         &(world_to_bsdf_space * info.retro),
                         &(world_to_bsdf_space * light.direction),
                         &light
                             .spectrum
-                            .emit_photon(&photon)
+                            .emit_photon(photon)
                             .scale_intensity(light.direction.dot(&info.normal).abs()),
                     ),
                 }
@@ -49,7 +49,7 @@ impl Integrator for WhittedIntegrator {
             .chain(
                 [info
                     .material
-                    .sample(&(world_to_bsdf_space * info.retro), &photon)]
+                    .sample(&(world_to_bsdf_space * info.retro), photon)]
                 .iter()
                 .map(|MaterialSampleResult { direction, pdf: _ }| {
                     let world_space_direction = bsdf_to_world_space * direction;
@@ -62,9 +62,9 @@ impl Integrator for WhittedIntegrator {
                                     &(world_to_bsdf_space * info.retro),
                                     direction,
                                     &self.integrate(
-                                        &sampler,
+                                        sampler,
                                         &recursive_hit,
-                                        &photon,
+                                        photon,
                                         recursion_limit - 1,
                                     ),
                                 );

src/math/vec3.rs

@@ -93,7 +93,7 @@ impl Vec3 {
     }
 
     pub fn norm_squared(&self) -> f64 {
-        self.dot(&self)
+        self.dot(self)
     }
 
     pub fn norm(&self) -> f64 {
@@ -119,12 +119,10 @@ impl Vec3 {
             } else {
                 2
             }
+        } else if y < z {
+            1
         } else {
-            if y < z {
-                1
-            } else {
-                2
-            }
+            2
         }
     }
 

src/mesh.rs

@@ -47,16 +47,16 @@ mod wavefront_obj {
     ) -> Vec<Triangle> {
         if let Some(v0_index) = polygon.iter().next() {
             let (v0_vertex, v0_normal) =
-                get_vertex_and_normal(v0_index, &vertex_positions, &normal_positions);
+                get_vertex_and_normal(v0_index, &vertex_positions, normal_positions);
             polygon
                 .iter()
                 .skip(1)
                 .zip(polygon.iter().skip(2))
                 .map(|(v1_index, v2_index)| {
                     let (v1_vertex, v1_normal) =
-                        get_vertex_and_normal(v1_index, &vertex_positions, &normal_positions);
+                        get_vertex_and_normal(v1_index, vertex_positions, normal_positions);
                     let (v2_vertex, v2_normal) =
-                        get_vertex_and_normal(v2_index, &vertex_positions, &normal_positions);
+                        get_vertex_and_normal(v2_index, vertex_positions, normal_positions);
                     let vertices = [v0_vertex, v1_vertex, v2_vertex];
                     let normals = [v0_normal, v1_normal, v2_normal];
                     Triangle {

src/random_distributions/cosine_weighted_hemisphere.rs

@@ -4,6 +4,7 @@ use crate::math::Vec3;
 
 use super::{RandomDistribution, UnitDisc};
 
+#[derive(Default)]
 pub struct CosineWeightedHemisphere {
     unit_disc: UnitDisc,
 }

src/random_distributions/sky_light_pdf.rs

@@ -18,6 +18,12 @@ impl SkyLightPdf {
     }
 }
 
+impl Default for SkyLightPdf {
+    fn default() -> SkyLightPdf {
+        SkyLightPdf::new()
+    }
+}
+
 impl RandomDistribution<Vec3> for SkyLightPdf {
     fn value(&self) -> Vec3 {
         let mut rng = thread_rng();

src/random_distributions/uniform_hemisphere.rs

@@ -7,6 +7,7 @@ use crate::math::Vec3;
 
 use super::RandomDistribution;
 
+#[derive(Default)]
 pub struct UniformHemisphere {}
 
 impl UniformHemisphere {

src/random_distributions/unit_disc.rs

@@ -9,6 +9,12 @@ pub struct UnitDisc {
     square_distribution: UniformSquare,
 }
 
+impl Default for UnitDisc {
+    fn default() -> UnitDisc {
+        UnitDisc::new()
+    }
+}
+
 impl UnitDisc {
     pub fn new() -> UnitDisc {
         let square_distribution = UniformSquare::new(Vec2::new(-1.0, -1.0), 2.0);

src/raycasting/bounding_volume_hierarchy.rs

@@ -92,24 +92,24 @@ fn closest_intersection(
 }
 
 impl Intersect for BoundingVolumeHierarchy {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo> {
         match self {
             BoundingVolumeHierarchy::Node {
                 bounds,
                 left,
                 right,
             } => {
-                if bounds.intersect(&ray) {
-                    closest_intersection(left.intersect(&ray), right.intersect(&ray))
+                if bounds.intersect(ray) {
+                    closest_intersection(left.intersect(ray), right.intersect(ray))
                 } else {
                     None
                 }
             }
             BoundingVolumeHierarchy::Leaf { bounds, primitives } => {
-                if bounds.intersect(&ray) {
+                if bounds.intersect(ray) {
                     primitives
                         .iter()
-                        .map(|elem| elem.intersect(&ray))
+                        .map(|elem| elem.intersect(ray))
                         .fold(None, closest_intersection)
                 } else {
                     None

src/raycasting/mod.rs

@@ -100,7 +100,7 @@ pub struct IntersectionInfo {
 /// intersected with a [Ray](Ray)
 pub trait Intersect: Send + Sync {
     /// Test if the ray intersects the object, and return information about the object and intersection.
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo>;
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo>;
 }
 
 /// A geometric object that can be intersected with a ray

src/raycasting/plane.rs

@@ -46,7 +46,7 @@ impl Plane {
 }*/
 
 impl Intersect for Plane {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo> {
         let ray_direction_dot_plane_normal = ray.direction.dot(&self.normal);
         let point_on_plane = self.normal * self.distance_from_origin;
         let point_on_plane_minus_ray_origin_dot_normal =

src/raycasting/sphere.rs

@@ -37,7 +37,7 @@ impl Sphere {
 }*/
 
 impl Intersect for Sphere {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect<'a>(&'_ self, ray: &Ray) -> Option<IntersectionInfo> {
         let r_o = ray.origin;
         let centre_coords = self.centre;
         let a = ray

src/raycasting/triangle.rs

@@ -33,7 +33,7 @@ pub struct Triangle {
 }*/
 
 impl Intersect for Triangle {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo> {
         let translation = -ray.origin;
         let indices = indices_with_index_of_largest_element_last(&ray.direction);
         let permuted_ray_direction = permute_vector_elements(&ray.direction, &indices);
@@ -126,7 +126,7 @@ fn is_valid_permutation(indices: &[usize; 3]) -> bool {
 }
 
 fn permute_vector_elements(v: &Vec3, indices: &[usize; 3]) -> Vec3 {
-    debug_assert!(is_valid_permutation(&indices));
+    debug_assert!(is_valid_permutation(indices));
     Vec3::new(v[indices[0]], v[indices[1]], v[indices[2]])
 }
 

src/raycasting/vec_aggregate.rs

@@ -9,9 +9,9 @@ impl HasBoundingBox for Vec<Box<dyn Primitive>> {
 }
 
 impl Intersect for Vec<Box<dyn Primitive>> {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo> {
         self.iter()
-            .flat_map(|primitive| primitive.intersect(&ray))
+            .flat_map(|primitive| primitive.intersect(ray))
             .min_by(
                 |a, b| match PartialOrd::partial_cmp(&a.distance, &b.distance) {
                     None => std::cmp::Ordering::Less,
@@ -32,9 +32,9 @@ impl HasBoundingBox for Vec<Box<dyn Aggregate>> {
 }
 
 impl Intersect for Vec<Box<dyn Aggregate>> {
-    fn intersect<'a>(&'a self, ray: &Ray) -> Option<IntersectionInfo> {
+    fn intersect(&self, ray: &Ray) -> Option<IntersectionInfo> {
         self.iter()
-            .flat_map(|aggregate| aggregate.intersect(&ray))
+            .flat_map(|aggregate| aggregate.intersect(ray))
             .min_by(
                 |a, b| match PartialOrd::partial_cmp(&a.distance, &b.distance) {
                     None => std::cmp::Ordering::Less,

src/sampler.rs

@@ -10,7 +10,7 @@ impl<'a> Sampler<'a> {
         self.scene
             .objects
             .iter()
-            .flat_map(|object| object.intersect(&ray))
+            .flat_map(|object| object.intersect(ray))
             .min_by(
                 |a, b| match PartialOrd::partial_cmp(&a.distance, &b.distance) {
                     None => std::cmp::Ordering::Less,

src/util/binary_tree.rs

@@ -1,5 +1,4 @@
-pub enum BinaryTree<Value, LeafValue>
-{
+pub enum BinaryTree<Value, LeafValue> {
     Branch {
         value: Value,
         left: Box<Self>,
@@ -11,8 +10,7 @@ pub enum BinaryTree<Value, LeafValue>
     None,
 }
 
-impl<Value, LeafValue> BinaryTree<Value, LeafValue>
-{
+impl<Value, LeafValue> BinaryTree<Value, LeafValue> {
     pub fn count_leaves(&self) -> usize {
         match self {
             Self::Branch {

src/util/polyhedra.rs

@@ -7,7 +7,7 @@ use crate::raycasting::{Primitive, Triangle};
 use std::sync::Arc;
 
 pub fn triangulate_polygon(
-    vertices: &Vec<Vec3>,
+    vertices: &[Vec3],
     normal: &Vec3,
     material: Arc<dyn Material>,
 ) -> Vec<Arc<dyn Primitive>> {
@@ -124,7 +124,7 @@ pub fn generate_dodecahedron(
         .iter()
         .flat_map(|face| {
             let normal = (face[1] - face[0]).cross(&(face[2] - face[1]));
-            let transformed_face = face.iter().map(|v| centre + v * scale).collect();
+            let transformed_face: Vec<_> = face.iter().map(|v| centre + v * scale).collect();
             triangulate_polygon(&transformed_face, &normal, Arc::clone(&material))
         })
         .collect()