diff --git a/src/main.rs b/src/main.rs index c0e78b2..bc8e645 100644 --- a/src/main.rs +++ b/src/main.rs @@ -1,7 +1,7 @@ mod primitives; -mod renderer; mod scene; +mod renderer; use crate::primitives::Vec3; use crate::scene::{ @@ -46,11 +46,11 @@ fn main() { // Iterate lines, submitting them as tasks to the thread. println!("P3\n{} {}\n255", image.0, image.1); let context = renderer::RenderContext { - camera: cam, + camera: &scene.camera, image, max_depth, samples_per_pixel, - world, + world: scene.world, }; thread::scope(|s| { diff --git a/src/primitives.rs b/src/primitives.rs index dc165d7..d8ca0f9 100644 --- a/src/primitives.rs +++ b/src/primitives.rs @@ -17,6 +17,96 @@ use rand::Rng; use rand::rngs::SmallRng; use rand::distributions::Uniform; +pub type Vec2i = Vec2; +pub type Vec2f = Vec2; + +#[derive (Clone, Copy, PartialEq, PartialOrd, Debug)] +pub struct Vec2{ + pub x: T, + pub y: T, +} + + +impl Vec2 { + pub fn zero() -> Vec2 { + Vec2{ x: 0.0, y: 0.0 } + } + + pub fn ones() -> Vec2 { + Vec2{ x: 1.0, y: 1.0 } + } + + pub fn rand(srng: &mut SmallRng, distrib: Uniform) -> Vec2 { + Vec2 { x: srng.sample(distrib), y: srng.sample(distrib) } + } + +} + +impl Vec2 +where T: std::ops::Mul{ + pub fn new(x: T, y: T) -> Vec2 { + Vec2{x, y} + } +} + +impl Add for Vec2 +where T: std::ops::Add{ + type Output = Vec2; + fn add(self, other: Vec2) -> Vec2 { + Vec2 { x: self.x + other.x, y: self.y + other.y } + } +} + +impl Mul for Vec2 +where T: std::ops::Mul{ + type Output = Vec2; + fn mul(self, other: Vec2) -> Vec2 { + Vec2 { + x: self.x * other.x, + y: self.y * other.y + } + } +} + +impl Div for Vec2{ + type Output = Vec2; + fn div(self, other: f32) -> Vec2 { + Vec2 { + x: 1.0/other * self.x, + y: 1.0/other * self.y + } + } +} + +impl Div for Vec2{ + type Output = Vec2; + fn div(self, other: i32) -> Vec2 { + Vec2 { + x: self.x / other, + y: self.y / other + } + } +} + +impl Div> for Vec2 +where T: std::ops::Div{ + type Output = Vec2; + fn div(self, other: Vec2) -> Vec2 { + Vec2 { + x: self.x / other.x, + y: self.y / other.y + } + } +} + +impl Display for Vec2 +where T: Display { // nested type still needs to have Display + fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + let str = format!("{} {}", self.x, self.y); + fmt.write_str(&str) + } +} + #[derive(Copy, Clone, PartialEq, PartialOrd, Debug)] pub struct Vec3{ pub x: f32, @@ -308,6 +398,22 @@ pub struct Rect { pub h: i32, } +impl Rect{ + pub fn pos(&self) -> Vec2i { + Vec2i { + x: self.x, + y: self.y, + } + } + + pub fn size(&self) -> Vec2i { + Vec2i { + x: self.w - self.x, + y: self.h - self.y, + } + } +} + #[cfg(test)] mod test{ use super::*; diff --git a/src/renderer.rs b/src/renderer.rs index 43b0dc8..febf774 100644 --- a/src/renderer.rs +++ b/src/renderer.rs @@ -1,270 +1,121 @@ -use crate::primitives::{Vec3, Ray, Rect}; +use crate::primitives::{ + Vec2i, + Vec2f, + Vec3, + Ray, + Rect, +}; use crate::scene::{ - Camera, Hittable, + Scene, }; -use core::cmp::Ordering; -use std::thread; -use std::sync::mpsc; -use std::ops; -use rand::Rng; use rand::rngs::SmallRng; use rand::distributions::Uniform; -use itertools::Itertools; -// ================= -// Description parts -// ================= +const SKY_COLOR: Vec3 = Vec3 { x: 0.5, y: 0.7, z: 1.0}; -#[derive (Clone)] -pub struct RenderContext{ - pub image: (i32, i32), - pub samples_per_pixel: u32, - pub max_depth: u32, - pub world: Hittable, - pub camera: Camera, +struct Distrs{ + zero_one: Uniform, + one_one: Uniform, } -pub struct DistributionContianer { - pub distrib_zero_one: Uniform, - pub distrib_plusminus_one: Uniform, +struct RenderProperties { + samples: u32, // samples are averaged results over a pixel + bounces: u32, // bounces are how far the ray will travel (in hits not total distance) } -impl DistributionContianer { - fn new() -> Self { - DistributionContianer { - distrib_zero_one: Uniform::new(0.0, 1.0), - distrib_plusminus_one: Uniform::new(-1.0, 1.0), - } - } +fn to_uv(coord: Vec2i, img_size: Vec2i) -> Vec2f { + let u = (coord.x as f32) / ((img_size.x - 1) as f32); + let v = (coord.y as f32) / ((img_size.y - 1) as f32); + Vec2f::new(u, v) } -// ============= -// Drawing Parts -// ============= - -fn render_line(y: i32, small_rng: &mut SmallRng, context: RenderContext, distr: &DistributionContianer) -> Vec { - //TODO: Ensure that the compiler hoists the distribution's out as constants - // else, do so manually - (0..context.image.0).map(|x| { - sample_pixel(x, y, small_rng, &context, distr) - }).collect() -} - -fn ray_color(r: Ray, world: &Hittable, depth: u32, srng: &mut SmallRng, distrib: Uniform ) -> Vec3 { - // recursion depth guard +fn ray_color( + r: Ray, surface: &Hittable, depth: u32, + rng: &mut SmallRng, + distr: &Distrs, +) -> Vec3 { + // recursion guard if depth == 0 { return Vec3::zero(); } - - if let Some(rec) = world.hit(r, 0.001, f32::INFINITY){ + + // cast a ray, interrogate hit record + if let Some(record) = surface.hit(r, 0.001, f32::INFINITY){ let mut scattered = Ray { orig: Vec3::zero(), - dir: Vec3::zero() + dir: Vec3::zero(), }; let mut attenuation = Vec3::zero(); - if rec.material.scatter(r, &rec, &mut attenuation, &mut scattered, srng) { - return attenuation * ray_color(scattered, world, depth-1, srng, distrib); - }; - } + if record.material.scatter( + r, + &record, + &mut attenuation, + &mut scattered, + rng + ) { + return attenuation * ray_color( + scattered, surface, depth-1, rng, distr + ); + } + } // TODO: explicit else block + // Rust gets angry about the inner if{} block because it evaluates to () + // when the else path is taken. This is a problem for a function + // that returns Vec3 and not (). - let unitdir = Vec3::as_unit(r.dir); - let t = 0.5 * (unitdir.y + 1.0); - return Vec3::ones() * (1.0 - t) + Vec3::new(0.5, 0.7, 1.0) * t + { // when nothing is struck, return sky color + let unitdir = Vec3::as_unit(r.dir); + let t = 0.5 * (unitdir.y + 1.0); + return Vec3::ones() * (1.0 - t) + SKY_COLOR * t + } } -fn sample_pixel(x: i32, y: i32, small_rng: &mut SmallRng, context: &RenderContext, distr: &DistributionContianer) -> Vec3{ - (0..context.samples_per_pixel).into_iter().fold( +fn sample_pixel( + coord: Vec2i, // location in image/screen space + scene: &Scene, // scene we're drawing + render_props: &RenderProperties, + img_size: Vec2i, + // Supplied by the execution environment (the thread) + rng: &mut SmallRng, + dist: &Distrs, +) -> Vec3{ + (0..render_props.samples) + .fold( Vec3::zero(), - |color, _sample| { - let u = ((x as f32) + small_rng.sample(distr.distrib_zero_one)) / ((context.image.0 - 1) as f32); - let v = ((y as f32) + small_rng.sample(distr.distrib_zero_one)) / ((context.image.1 - 1) as f32); - let ray = context.camera.get_ray(u, v, small_rng); - color + ray_color(ray, &context.world, context.max_depth, small_rng, distr.distrib_plusminus_one) + |color, _sample| -> Vec3 { + let uv = to_uv(coord, img_size); + let ray = scene.camera.get_ray(uv.x, uv.y, rng); + color + ray_color(ray, &scene.world, render_props.bounces, rng, dist) } ) } -// =============== -// Execution parts -// =============== - -/* Iterable that produces pixels left-to-right, top-to-bottom. - * `Tile`s represent the render space, not the finished image. - * There is no internal pixel buffer - */ - -type TileCursorIter = itertools::Product, ops::Range>; - struct Tile { bounds: Rect, - context: RenderContext, - small_rng: SmallRng, - rand_distr: DistributionContianer, - cursor: TileCursorIter, + pixels: Vec, } -impl Tile{ - fn new( - bounds: Rect, - context: RenderContext, - small_rng: SmallRng, - rand_distr: DistributionContianer - ) -> Self - { - Tile { bounds, context, small_rng, rand_distr, - cursor: (bounds.x..(bounds.x + bounds.w)) - .cartesian_product(bounds.y..(bounds.y + bounds.h) +impl Tile { + pub fn render_line( + bounds: Rect, y: i32, // bounding rect and line + scene: &Scene, + properties: &RenderProperties, + rng: &mut SmallRng, distr: &Distrs // rng utils + ) -> Self { + let pixels = (0..bounds.w) + .map ( |x| -> Vec3{ + sample_pixel( + Vec2i{x, y}, + scene, + properties, + bounds.size(), + rng, + distr ) - } - + }) + .collect(); + Self { bounds, pixels } } } - -impl Iterator for Tile { - type Item = Vec3; - fn next(&mut self) -> Option { - if let Some((x, y)) = self.cursor.next(){ - Some(sample_pixel( - x, y, - &mut self.small_rng, - &self.context, - &self.rand_distr, - )) - } else { - None - } - } -} - - - -#[derive (Clone)] -pub enum RenderCommand{ - Stop, - Line { line_num: i32, context: RenderContext }, -} - -pub struct RenderResult { - pub line_num: i32, - pub line: Vec, -} - -impl Ord for RenderResult { - fn cmp(&self, other: &Self) -> Ordering { - if self.line_num > other.line_num { - Ordering::Less - } else if self.line_num < other.line_num { - Ordering::Greater - } else { - Ordering::Equal - } - } -} - -impl PartialOrd for RenderResult { - fn partial_cmp(&self, other: &Self) -> Option { - Some(self.cmp(other)) - } -} - -impl PartialEq for RenderResult { - fn eq(&self, other: &Self) -> bool { - self.line_num == other.line_num - } -} - -impl Eq for RenderResult {} - -/* - * The dispatcher will hold a list of threads, and a list of command input channels to match. - * Helper functions exist to input jobs serially, and then dispatch them to an open thread. - * - * Since receivers can be matched to several senders, the input end of the result channel will - * be cloned and given to each of the threads. - * TODO: Consider holding a copy of the render_tx end in case threads exit early and need to - * be restored. - */ -pub struct Dispatcher{ - handles: Vec>, - command_transmitters: Vec>, - next_to_feed: usize, // gonna do a round-robin style dispatch, ig. -} - -impl Dispatcher { - pub fn new(srng: &SmallRng, num_threads: usize) -> (Dispatcher, mpsc::Receiver ) { - let mut handles = Vec::new(); - let mut command_transmitters = Vec::>::new(); - - let (render_tx, render_rx) = mpsc::sync_channel::(1); - - for _ in 0..num_threads { - // create new command tx/rx pairs. Store tx in the list, give rx to the thread. - let (command_tx, command_rx) = mpsc::sync_channel::(1); - // TODO: Pick appropriate command queue depth (or make it controllable, even) - - - let mut srng = srng.clone(); - let threads_result_tx = render_tx.clone(); - let distribs = DistributionContianer::new(); - let thread_handle = thread::spawn(move || { - while let Ok(job) = command_rx.recv() { - match job { - RenderCommand::Stop => { - break; - } - RenderCommand::Line { line_num, context } => { - let line = render_line(line_num, &mut srng, context, &distribs); - let result = RenderResult { line_num, line }; - threads_result_tx.send(result).unwrap(); - } - } - } - }); - handles.push(thread_handle); - command_transmitters.push(command_tx); - } - // finally, stash everything in the Dispatcher struct and return. - ( - Dispatcher{ - handles, - command_transmitters, - next_to_feed: 0, - }, - render_rx - ) - } - - //TODO: Reconsider round-robin dispatch - // When passing the message to threads which are still busy, this function - // will block (it's a sync_channel). While blocked, other threads could - // become available and left idle. - pub fn submit_job(&mut self, command: RenderCommand) -> Result<(), mpsc::SendError> { - // Stop command is special. We'll broadcast it to all threads. - if let RenderCommand::Stop = command { - for channel in &self.command_transmitters { - return channel.send(command.clone()); - } - } - - // Check that `next_to_feed` is in-bounds, and then insert. - // index is post-incremented with this function call. - - // wrap when at length (0-indexed so last valid index is len-1) - if self.next_to_feed == self.handles.len() { - self.next_to_feed = 0; - } else if self.next_to_feed > self.handles.len() { - panic!("How the hell did a +=1 skip past the maximum allowed size?"); - } - - match self.command_transmitters.get(self.next_to_feed){ - Some(target) => target.send(command).unwrap(), - None => panic!("oh god oh fuck"), - } - self.next_to_feed += 1; - Ok(()) - } -} - diff --git a/src/scene.rs b/src/scene.rs index eb984a0..17a9432 100644 --- a/src/scene.rs +++ b/src/scene.rs @@ -169,7 +169,6 @@ pub fn degrees_to_radians(degrees: f32) -> f32 { degrees * std::f32::consts::PI / 180.0 } -#[derive (Clone, Copy)] pub struct Camera { origin: Vec3, lower_left_corner: Vec3,