static long long timestamp()
    {
        //From http://gamedev.stackexchange.com/questions/26759/best-way-to-get-elapsed-time-in-miliseconds-in-windows
        static LARGE_INTEGER s_frequency;
        static BOOL s_use_qpc = QueryPerformanceFrequency(&s_frequency);
        if (s_use_qpc)
        {
            LARGE_INTEGER now;
            QueryPerformanceCounter(&now);
            return (1000LL * now.QuadPart) / s_frequency.QuadPart;
        }
        else
        {
            return GetTickCount();
        }
    }