Put a pixel on the screen with Rust!

Cargo.toml

[package]
name = "pixel"
version = "0.1.0"
edition = "2021"

[dependencies]
sdl2 = { version = "0.34.5", features = ["bundled"] }

main.rs

use sdl2::{event::Event, keyboard::Keycode, pixels::Color};

const WIDTH: u32 = 800;
const HEIGHT: u32 = 600;
const PIXEL_SIZE: u32 = 1;

fn main() -> Result<(), String> {
    let sdl_context = sdl2::init()?;
    let video_subsystem = sdl_context.video()?;

    let window = video_subsystem
        .window("SDL2 Green Pixel", WIDTH, HEIGHT)
        .position_centered()
        .build()
        .map_err(|e| e.to_string())?;

    let mut canvas = window.into_canvas().build().map_err(|e| e.to_string())?;

    let mut event_pump = sdl_context.event_pump()?;

    'running: loop {
        for event in event_pump.poll_iter() {
            match event {
                Event::Quit { .. }
                | Event::KeyDown {
                    keycode: Some(Keycode::Escape),
                    ..
                } => break 'running,
                _ => {}
            }
        }

        canvas.set_draw_color(Color::RGB(0, 0, 0));
        canvas.clear();

        canvas.set_draw_color(Color::RGB(0, 255, 0));
        canvas.fill_rect(sdl2::rect::Rect::new(
            (WIDTH / 2) as i32,
            (HEIGHT / 2) as i32,
            PIXEL_SIZE,
            PIXEL_SIZE,
        ))?;

        canvas.present();

        ::std::thread::sleep(::std::time::Duration::new(0, 1_000_000_000u32 / 60));
    }

    Ok(())
}