extern crate instant;
use instant::Instant;
use std::{collections::VecDeque, time::Duration};
#[derive(Debug)]
pub struct FPSCounter {
last_second_frames: VecDeque<Instant>,
}
impl Default for FPSCounter {
fn default() -> Self {
FPSCounter::new()
}
}
impl FPSCounter {
pub fn new() -> FPSCounter {
FPSCounter {
last_second_frames: VecDeque::with_capacity(128),
}
}
pub fn tick(&mut self) -> usize {
let now = Instant::now();
let a_second_ago = now - Duration::from_secs(1);
while self
.last_second_frames
.front()
.map_or(false, |t| *t < a_second_ago)
{
self.last_second_frames.pop_front();
}
self.last_second_frames.push_back(now);
self.last_second_frames.len()
}
}