softbuffer/examples/fruit.rs

use image::GenericImageView;
use std::num::NonZeroU32;
use winit::event::{Event, WindowEvent};
use winit::event_loop::{ControlFlow, EventLoop};
use winit::window::WindowBuilder;

fn main() {
    //see fruit.jpg.license for the license of fruit.jpg
    let fruit = image::load_from_memory(include_bytes!("fruit.jpg")).unwrap();

    let event_loop = EventLoop::new();
    let window = WindowBuilder::new()
        .with_inner_size(winit::dpi::PhysicalSize::new(fruit.width(), fruit.height()))
        .build(&event_loop)
        .unwrap();

    #[cfg(target_arch = "wasm32")]
    {
        use winit::platform::web::WindowExtWebSys;

        web_sys::window()
            .unwrap()
            .document()
            .unwrap()
            .body()
            .unwrap()
            .append_child(&window.canvas())
            .unwrap();
    }

    let context = unsafe { softbuffer::Context::new(&window) }.unwrap();
    let mut surface = unsafe { softbuffer::Surface::new(&context, &window) }.unwrap();

    event_loop.run(move |event, _, control_flow| {
        *control_flow = ControlFlow::Wait;

        match event {
            Event::RedrawRequested(window_id) if window_id == window.id() => {
                surface
                    .resize(
                        NonZeroU32::new(fruit.width()).unwrap(),
                        NonZeroU32::new(fruit.height()).unwrap(),
                    )
                    .unwrap();

                let mut buffer = surface.buffer_mut().unwrap();
                let width = fruit.width() as usize;
                for (x, y, pixel) in fruit.pixels() {
                    let red = pixel.0[0] as u32;
                    let green = pixel.0[1] as u32;
                    let blue = pixel.0[2] as u32;

                    let color = blue | (green << 8) | (red << 16);
                    buffer[y as usize * width + x as usize] = color;
                }

                buffer.present().unwrap();
            }
            Event::WindowEvent {
                event: WindowEvent::CloseRequested,
                window_id,
            } if window_id == window.id() => {
                *control_flow = ControlFlow::Exit;
            }
            _ => {}
        }
    });
}