/* This class is intended to be used in a loop as a simple method of limiting the loop to
 * a certain number of iterations per second. Usually, that would be video at 30 frames per
 * second.
 *
 * while( true ) {
 *    rate_limiter lim(0.033);
 *    // grab a frame of video and process it
 * }
 */
#include <boost/thread/thread.hpp>
#include <iostream>

#include "rate_limiter.h"


rate_limiter::rate_limiter( float secs ) : m_secs(secs)
{
    boost::xtime_get(&xt, boost::TIME_UTC);
    int sec_part = static_cast<int>(secs);
//        std::cout << xt.sec << "  " << xt.nsec << std::endl;
    xt.sec += sec_part;
    xt.nsec += (m_secs - static_cast<float>(sec_part)) * 1000000000.0;
//        std::cout << secs << "  " << sec_part << "  " << (m_secs - sec_part) << std::endl;
//        std::cout << xt.sec << "  " << xt.nsec << std::endl;
}

rate_limiter::~rate_limiter()
{
    boost::thread::sleep(xt);
}

#ifdef TEST_RATE_LIMITER
int main( int argc, char *argv[] )
{
    if( argc > 1 )
    {
        rate_limiter outer(0.5); // this one should have no effect, since the inner loop should take more than 0.5 seconds
        for( int x = 30; x > 0; --x )
            rate_limiter blah(0.033);
    }
    return 0;
}
#endif