sdl_rand_pix.rs

use std::process;
use std::thread;
use std::time::Duration;

use rand::Rng;

use sdl2::event::Event;
use sdl2::pixels::PixelFormatEnum;

const WIDTH: usize = 256;
const HEIGHT: usize = 240;

pub fn main() {
    let sdl_context = sdl2::init().unwrap();
    let video_subsystem = sdl_context.video().unwrap();

    let window = video_subsystem.window("NESTY", (WIDTH * 2) as u32, (HEIGHT * 2) as u32)
        .position_centered()
        .build()
        .unwrap();

    let mut canvas = window.into_canvas().build().unwrap();
    let texture_creator = canvas.texture_creator();

    let mut texture = texture_creator
        .create_texture_streaming(PixelFormatEnum::RGB24, WIDTH as u32, HEIGHT as u32)
        .unwrap();

    let mut pixels = [0 as u8; WIDTH * HEIGHT * 3];
    let mut rng = rand::thread_rng();

    let mut event_pump = sdl_context.event_pump().unwrap();

    loop {
        for event in event_pump.poll_iter() {
            match event {
                Event::Quit { .. } => process::exit(0),
                _ => {}
            }
        }

        for y in 0..HEIGHT {
            for x in 0..WIDTH {
                let offset = y * WIDTH * 3 + x * 3;
                pixels[offset    ] = rng.gen::<u8>();
                pixels[offset + 1] = rng.gen::<u8>();
                pixels[offset + 2] = rng.gen::<u8>();
            }
        }

        texture.update(None, &pixels, WIDTH * 3).unwrap();
        canvas.copy(&texture, None, None).unwrap();
        canvas.present();

        thread::sleep(Duration::from_millis(17));
    }
}