Simple FPS Limit in Rust/Vulkano

60fps.rs

// I don't know if this is the "right" way to do this, or even a "not stupid" way to do this, but I couldn't
// find an idiomatic approach and I'm a noob at Vulkan and graphics programming in general, so I came up with this
// the only reason it was difficult is that I first had to learn how Rust likes doing timing, using Duration and Instant
// rather than just using a ms/ns timestamp integer as one might expect
fn main() {
    // [...] all your vulkan initialization stuff
    
    // this is the target FPS
    let fps = 60u32;
    // set up a Duration representing the frame interval
    let frame_interval = Duration::new(0, 1000000000u32/fps);
    // this is stored as an Instant, representing the current time from an arbitrary epoch
    let mut frame_start:Instant;
    // this is where we'll store the delta (time from beginning of frame to completing it)
    let mut frame_delta:Duration;
    
    // these are used to display fps, can omit them if you don't want to do that
    let mut frame_count_start = Instant::now(); 
    let mut frame_count = 0f64;
    let mut frame_count_elapsed:f64;
    
    // main render loop
    loop {
        frame_start = Instant::now();

        // ...
        // all your render loop stuff goes here
        // ...

        
        // calculate fps
        frame_count = frame_count + 1f64;
        frame_count_elapsed = frame_count_start.elapsed().as_secs() as f64 + (frame_count_start.elapsed().subsec_nanos() as f64 / 1000000000f64);
        // print fps to stdout
        print!("\rFPS: {:.2}", frame_count / frame_count_elapsed);
        
        // go to sleep for remainder of frame_interval
        frame_delta = frame_start.elapsed();
        if frame_delta < frame_interval {thread::sleep(frame_interval - frame_delta)};
    }