如果没有数据等待,从mpsc :: channel抓取数据而不锁定它

时间:2016-04-05 13:09:57

标签: multithreading asynchronous rust

我正在Rust写一个小游戏来学习多线程。我得到的代码包含两个循环,一个包含逻辑,一个包含渲染,如下所示:

let (t1_entity_in, t1_entity_out) = mpsc::channel(); // ommited type definitions

let (t1_event_in, t1_event_out) = mpsc::channel();

let entity = Entity::new(20,20);

std::thread::spawn(move || {
     let window = Window::new(1280,720);
     loop {
         // waits until parent send data
         let entity = t1_entity_out.recv().unwrap();
         window.draw(entity);
         window.flip();
         let events = window.get_events();
         // parent starts working
     }
});

'event_loop: loop {
    // do stuff to the entity
    t1_entity_in.send(entity.clone());
    // thread 1 starts workinng

    // waits until thread 1 sends data
    let events = t1_event_out.recv().unwrap(); // [1]
    // thread 1 sent data, continues.
    for event in events {
        if event.type == event::QUIT { 
            break 'event_loop;
        }
    }
}

此代码有效,但它的行为与单线程的行为相同。我想要的行为是在标记为[1]的行,如果有一个事件迭代器在等待,那么就得到它,但是如果没有,那就给我一个None并继续。我该怎么做?

1 个答案:

答案 0 :(得分:2)

我认为你需要try_recv()

let events = match t1_event_out.try_recv() {
    Ok(events) => events,
    Err(TryRecvError::Empty) => continue,
    Err(TryRecvError::Disconnected) => break,
};