annotate base/RealTime.h @ 6:44bbf5793d84

* Rework handling of layer properties in file I/O -- we now get the individual
  layers to load and save them rather than doing it via generic property lists
  in the base class, so as to ensure we read and write meaningful values rather
  than generic int values requiring conversion.

/* -*- c-basic-offset: 4 -*-  vi:set ts=8 sts=4 sw=4: */

/*
    A waveform viewer and audio annotation editor.
    Chris Cannam, Queen Mary University of London, 2005-2006
    
    This is experimental software.  Not for distribution.
*/

/*
   This is a modified version of a source file from the 
   Rosegarden MIDI and audio sequencer and notation editor.
   This file copyright 2000-2005 Chris Cannam.
*/

#ifndef _REAL_TIME_H_
#define _REAL_TIME_H_

#include <iostream>
#include <string>

/**
 * RealTime represents time values to nanosecond precision
 * with accurate arithmetic and frame-rate conversion functions.
 */

struct RealTime
{
    int sec;
    int nsec;

    int usec() const { return nsec / 1000; }
    int msec() const { return nsec / 1000000; }

    RealTime(): sec(0), nsec(0) {}
    RealTime(int s, int n);

    RealTime(const RealTime &r) :
	sec(r.sec), nsec(r.nsec) { }

    RealTime &operator=(const RealTime &r) {
	sec = r.sec; nsec = r.nsec; return *this;
    }

    RealTime operator+(const RealTime &r) const {
	return RealTime(sec + r.sec, nsec + r.nsec);
    }
    RealTime operator-(const RealTime &r) const {
	return RealTime(sec - r.sec, nsec - r.nsec);
    }
    RealTime operator-() const {
	return RealTime(-sec, -nsec);
    }

    bool operator <(const RealTime &r) const {
	if (sec == r.sec) return nsec < r.nsec;
	else return sec < r.sec;
    }

    bool operator >(const RealTime &r) const {
	if (sec == r.sec) return nsec > r.nsec;
	else return sec > r.sec;
    }

    bool operator==(const RealTime &r) const {
        return (sec == r.sec && nsec == r.nsec);
    }
 
    bool operator!=(const RealTime &r) const {
        return !(r == *this);
    }
 
    bool operator>=(const RealTime &r) const {
        if (sec == r.sec) return nsec >= r.nsec;
        else return sec >= r.sec;
    }

    bool operator<=(const RealTime &r) const {
        if (sec == r.sec) return nsec <= r.nsec;
        else return sec <= r.sec;
    }

    RealTime operator/(int d) const;

    // Find the fractional difference between times
    //
    double operator/(const RealTime &r) const;

    // Return a human-readable debug-type string to full precision
    // (probably not a format to show to a user directly)
    // 
    std::string toString() const;

    // Return a user-readable string to the nearest millisecond
    // in a form like HH:MM:SS.mmm
    //
    std::string toText(bool fixedDp = false) const;

    // Convenience functions for handling sample frames
    //
    static long realTime2Frame(const RealTime &r, unsigned int sampleRate);
    static RealTime frame2RealTime(long frame, unsigned int sampleRate);

    static const RealTime zeroTime;
};

std::ostream &operator<<(std::ostream &out, const RealTime &rt);
    
#endif