rust-sdl2/examples/renderer-target.rs

extern crate sdl2;

use sdl2::event::Event;
use sdl2::keyboard::Keycode;
use sdl2::pixels::{Color, PixelFormatEnum};
use sdl2::rect::{Point, Rect};

fn main() {
    let sdl_context = sdl2::init().unwrap();
    let video_subsystem = sdl_context.video().unwrap();
    let window = video_subsystem
        .window("rust-sdl2 resource-manager demo", 800, 600)
        .position_centered()
        .build()
        .unwrap();
    let mut canvas = window.into_canvas().software().build().unwrap();
    let creator = canvas.texture_creator();
    let mut texture = creator
        .create_texture_target(PixelFormatEnum::RGBA8888, 400, 300)
        .unwrap();

    let mut angle = 0.0;

    'mainloop: loop {
        for event in sdl_context.event_pump().unwrap().poll_iter() {
            match event {
                Event::KeyDown { keycode: Some(Keycode::Escape), .. } |
                Event::Quit { .. } => break 'mainloop,
                _ => {}
            }
        }
        angle = (angle + 0.5) % 360.;
        canvas.with_texture_canvas(&mut texture, |texture_canvas| {
            texture_canvas.clear();
            texture_canvas.set_draw_color(Color::RGBA(255, 0, 0, 255));
            texture_canvas.fill_rect(Rect::new(0, 0, 400, 300)).unwrap();
        }).unwrap();
        canvas.set_draw_color(Color::RGBA(0, 0, 0, 255));
        let dst = Some(Rect::new(0, 0, 400, 300));
        canvas.clear();
        canvas
            .copy_ex(&texture,
                     None,
                     dst,
                     angle,
                     Some(Point::new(400, 300)),
                     false,
                     false)
            .unwrap();
        canvas.present();
    }
}