maaaath :33

raytracer/src/buffer.rs

@@ -6,8 +6,8 @@ use alloc::vec::Vec;
 use uefi::Error;
 
 pub struct Buffer {
-    width: usize,
-    height: usize,
+    pub width: usize,
+    pub height: usize,
     pixels: Vec<BltPixel>,
 }
 
@@ -37,11 +37,7 @@ impl Buffer {
     }
 
     /// Update only a pixel to the framebuffer.
-    fn blit_pixel(
-        &self,
-        gop: &mut GraphicsOutput,
-        coords: (usize, usize),
-    ) -> Result<(), Error> {
+    fn blit_pixel(&self, gop: &mut GraphicsOutput, coords: (usize, usize)) -> Result<(), Error> {
         gop.blt(BltOp::BufferToVideo {
             buffer: &self.pixels,
             src: BltRegion::SubRectangle {

raytracer/src/main.rs

@@ -1,29 +1,28 @@
 #![no_main]
 #![no_std]
 
-
 mod buffer;
+mod ray;
+mod renderer;
 extern crate alloc;
 
+use crate::buffer::Buffer;
 use uefi::allocator::Allocator;
 use uefi::boot::ScopedProtocol;
 use uefi::prelude::*;
 use uefi::proto::console::gop::GraphicsOutput;
-use uefi::{boot, Result};
-use crate::buffer::Buffer;
+use uefi::{Result, boot};
 
 #[global_allocator]
 static ALLOCATOR: Allocator = uefi::allocator::Allocator;
 
 fn init_gop() -> Result<ScopedProtocol<GraphicsOutput>> {
-            // Open graphics output protocol.
+    // Open graphics output protocol.
     let gop_handle = boot::get_handle_for_protocol::<GraphicsOutput>()?;
     boot::open_protocol_exclusive::<GraphicsOutput>(gop_handle)
 }
 
-
-
-fn init_buffer(gop: &GraphicsOutput) -> Buffer{
+fn init_buffer(gop: &GraphicsOutput) -> Buffer {
     // Create a buffer to draw into.
     let (width, height) = gop.current_mode_info().resolution();
     Buffer::new(width, height)

raytracer/src/ray.rs

@@ -0,0 +1,58 @@
+use alloc::vec::Vec;
+use cgmath::{Matrix4, Vector3, Vector4, num_traits::Num};
+
+pub struct Ray<T> {
+    pub(crate) origin: Vector3<T>,
+    pub(crate) direction: Vector3<T>,
+}
+
+pub fn construct_primary_rays(
+    (width, height): (usize, usize),
+    (pixel_x_coord, pixel_y_coord): (usize, usize),
+    cam_to_world_matrix: &Matrix4<f32>,
+    focal_length: f32,
+    rays_per_pixel: usize,
+) -> Vec<Ray> {
+    let mut rays: Vec<Ray> = Vec::with_capacity(rays_per_pixel);
+
+    //generate all rays for this pixel and add them to the rays vector
+    for _ in 0..rays_per_pixel {
+        rays.push(generate_single_primary_ray(
+            (width, height),
+            cam_to_world_matrix,
+            focal_length,
+            pixel_x_coord,
+            pixel_y_coord,
+            //no noise
+            0.0f,
+            0.0f,
+        ));
+    }
+
+    rays
+}
+
+fn generate_single_primary_ray(
+    (buffer_width, buffer_height): (usize, usize),
+    cam_to_world_transform: &Matrix4<f32>,
+    focal_length: f32,
+    u: usize,
+    v: usize,
+    u_offset: f32,
+    v_offset: f32,
+) -> Ray {
+    //calculate the ray direction and translate it to world space
+    let direction_camera_space: Vector4<f32> = Vector4::new(
+        u as f32 - (buffer_width as f32 / 2.0) + u_offset,
+        v as f32 - (buffer_height as f32 / 2.0) + v_offset,
+        focal_length,
+        0.0,
+    );
+
+    let direction_world_space = cam_to_world_transform * direction_camera_space.normalize();
+
+    Ray {
+        origin: cam_to_world_transform.w.truncate(),
+        direction: direction_world_space.truncate().normalize(),
+    }
+}

raytracer/src/renderer.rs

@@ -0,0 +1,31 @@
+use alloc::vec::Vec;
+use cgmath::{Matrix4, Vector4, Zero};
+
+use crate::{
+    buffer::Buffer,
+    ray::{Ray, construct_primary_rays},
+};
+
+pub fn render(buffer: Buffer) {
+    let camera_matrix: Matrix4<f32> = Matrix4 {
+        x: Vector4::unit_x(),
+        y: Vector4::unit_y(),
+        z: Vector4::unit_z(),
+        w: Vector4::zero(),
+    };
+
+    let focal_length = 1.0f;
+
+    //this reeeeally wants to run in parallel…
+    (0..buffer.width).for_each(|x| {
+        (0..buffer.height).for_each(|y| {
+            let rays: Vec<Ray<f32>> = construct_primary_rays(
+                (buffer.width, buffer.height),
+                (x, y),
+                camera_matrix,
+                focal_length,
+                1,
+            );
+        });
+    });
+}