sleeper.cpp

sleeper.cpp

#include <chrono>
#include <iostream>
#include <thread>
#include <atomic>
#include <cmath>
#include <vector>
#include <algorithm>

using namespace std;
using namespace std::chrono;

int main()
{
    atomic_int thingy = 0;
    atomic<chrono::time_point<chrono::high_resolution_clock>> sent = chrono::high_resolution_clock::now();

    thread runner([&thingy, &sent] {
        int localThingy = 0;
        std::vector<double> waitsPerFrame;
        waitsPerFrame.reserve(1000);

        while(1)
        {
            waitsPerFrame.clear();

            while(localThingy > thingy.load())
            {
                //this_thread::yield();
                this_thread::sleep_for(1ms);

                auto received = chrono::high_resolution_clock::now();
                waitsPerFrame.push_back(chrono::duration_cast<chrono::microseconds>(received - sent.load()).count() / 1000.0);
            }

            static int t = 0;
            t++;
            if(t % 60 == 0)
            {
                cout << "latency range: " << *min_element(waitsPerFrame.begin(), waitsPerFrame.end()) << " ms to ";
                cout << *max_element(waitsPerFrame.begin(), waitsPerFrame.end()) << " ms" << endl;
            }

            localThingy++;
            //cout << "doing things at 60 fps" << endl;
        }
    });

    while(1)
    {
        sent = chrono::high_resolution_clock::now();
        thingy++;

        int usec = (int)round((1.0 / 60) * 1000000);
        std::this_thread::sleep_until(steady_clock::now() + microseconds(usec));
    }
    return 0;
}