用英语设置帧重绘速率

Question

我正试图在rust中使用glium制作一个游戏循环。我的目标是让屏幕每秒重绘60次。使用我现有的当前事件循环代码，只有当窗口大小发生变化时，才会重新绘制帧。我在glutin文档中读到，我需要在某个地方调用request_redraw，但我不确定如何/在哪里调用。这是我迄今为止的代码：

event_loop.run(move |event, _target, control_flow| match event {
Event::LoopDestroyed => return,
Event::WindowEvent {
window_id: _window_id,
event: winevent,
} => match winevent {
WindowEvent::Resized(physical_size) => display.gl_window().resize(physical_size),
WindowEvent::CloseRequested => {
*control_flow = ControlFlow::Exit;
}
_ => {}
},
Event::RedrawRequested(_window_id) => {
let mut target = display.draw();
target.clear_color_srgb(rng.gen(), rng.gen(), rng.gen(), 1.0);
target.finish().unwrap();
}
_ => {}
});

Answer 1

我以前从未使用过glium(有一段时间我一直在直接使用Vulkano制作一些图形应用程序(。然而，仔细阅读API，似乎可以通过一系列API从winit中获取窗口句柄。我在下面的代码中概述了它们。下面这样的东西应该对你有用。关键是从winit获取对Window句柄的访问权限。滚动WindowAPI，您应该看到以下内容：request_redraw。然后，您可以在事件处理程序周围插入游戏循环逻辑，如下所示：

use std::time::Instant;
use glium::Display;
use winit::event_loop::{EventLoop, ControlFlow};
use winit::event::{Event, WindowEvent};
use winit::window::Window;
const TARGET_FPS: u64 = 60;
/* ... some function for main loop ... */
let display: Display = ... /* glium Display instance */
event_loop.run(move |event, _target, control_flow| {
let start_time = Instant::now();
match event {
Event::WindowEvent { event: WindowEvent::CloseRequested, .. } => {
*control_flow = ControlFlow::Exit;
},
...
/*
* Process events here
*/
}
match *control_flow {
ControlFlow::Exit => (),
_ => {
/*
* Grab window handle from the display (untested - based on API)
*/
display.gl_window().window().request_redraw();
/*
* Below logic to attempt hitting TARGET_FPS.
* Basically, sleep for the rest of our milliseconds
*/
let elapsed_time = Instant::now().duration_since(start_time).as_millis() as u64;
let wait_millis = match 1000 / TARGET_FPS >= elapsed_time {
true => 1000 / TARGET_FPS - elapsed_time,
false => 0
};
let new_inst = start_time + std::time::Duration::from_millis(wait_millis);
*control_flow = ControlFlow::WaitUntil(new_inst);
}
}
});