Minor optimization

src/main.rs

@@ -18,11 +18,28 @@ mod view;
 use view::View;
 
 fn main() {
-    let input_data = [Triangle::new(
+    let input_data = [
+        Triangle::new(
             vec3(0.0, 0.0, 0.0),
             vec3(1.0, 0.0, 0.0),
             vec3(1.0, 1.0, 0.0),
-    )];
+        ),
+        Triangle::new(
+            vec3(1.0, 1.0, 0.0),
+            vec3(0.0, 1.0, 0.0),
+            vec3(0.0, 0.0, 0.0),
+        ),
+        Triangle::new(
+            vec3(1.0, 1.0, 0.0),
+            vec3(2.0, 1.0, 0.0),
+            vec3(2.0, 2.0, 0.0),
+        ),
+        Triangle::new(
+            vec3(2.0, 2.0, 0.0),
+            vec3(1.0, 2.0, 0.0),
+            vec3(1.0, 1.0, 0.0),
+        ),
+    ];
 
     let view = View {
         position: vec3(0.0, -4.0, 4.0),
@@ -31,6 +48,8 @@ fn main() {
         fov: 45.0,
     };
 
+    let debug_ray = Ray::primary_ray(640.0, 360.0, 1280.0, 720.0, &view);
+
     debug_raytracer(1280, 720, &view, &input_data);
 }
 
@@ -95,12 +114,12 @@ fn look_at_test(eye: Vector3<f32>, center: Vector3<f32>, up: Vector3<f32>) -> Ma
 fn debug_raytracer(dim_x: u32, dim_y: u32, view: &View, data: &[Triangle]) {
     let mut imgbuf = ImageBuffer::new(dim_x, dim_y);
 
-    for (x, y, pixel) in imgbuf.enumerate_pixels_mut() {
-        let ray = Ray::primary_ray(x, y, dim_x, dim_y, view);
-
     let acceleration_data = create_acceleration_data(data);
 
-        let color = pixel_color(&ray, data, acceleration_data);
+    for (x, y, pixel) in imgbuf.enumerate_pixels_mut() {
+        let ray = Ray::primary_ray(x as f32, y as f32, dim_x as f32, dim_y as f32, view);
+
+        let color = pixel_color(&ray, data, &acceleration_data);
 
         *pixel = image::Rgb([f_to_u(color.x), f_to_u(color.y), f_to_u(color.z)]);
     }
@@ -157,7 +176,7 @@ fn create_acceleration_data(input_data: &[Triangle]) -> Vec<AABB> {
     acceleration_data
 }
 
-fn pixel_color(ray: &Ray, data: &[Triangle], acceleration_data: Vec<AABB>) -> Vector3<f32> {
+fn pixel_color(ray: &Ray, data: &[Triangle], acceleration_data: &Vec<AABB>) -> Vector3<f32> {
     let mut final_color = vec3(0.0, 1.0, 0.0);
     let mut closest_value = MAX;
     let mut closest_index = -1;

src/ray.rs

@@ -25,17 +25,23 @@ impl Ray {
         }
     }
 
-    pub fn primary_ray(x: u32, y: u32, dim_y: u32, dim_x: u32, view: &View) -> Ray {
+    pub fn primary_ray(x: f32, y: f32, dim_x: f32, dim_y: f32, view: &View) -> Ray {
-        let aspect_ratio = dim_x as f32 / dim_y as f32;
+        let aspect_ratio = dim_x / dim_y;
 
-        let uv = vec2(x as f32, y as f32);
+        let uv = vec2((x + 0.5) / dim_x, (y + 0.5) / dim_y);
 
         let (up, right) = view.axises();
 
         let trans = 2.0 * uv - vec2(1.0, 1.0);
-        let mut dir = view.look_at + right * trans.x + up * trans.y;
+        let raw_dir = view.look_at + right * trans.x + up * trans.y;
-        dir = vec3(dir.x * aspect_ratio, dir.y, dir.z * aspect_ratio);
 
-        return Self::new(view.position, dir.normalize());
+        let dir = vec3(
+            raw_dir.x * aspect_ratio,
+            raw_dir.y,
+            raw_dir.z * aspect_ratio,
+        )
+        .normalize();
+
+        return Self::new(view.position, dir);
     }
 }