annotate base/RealTime.h @ 492:23945cdd7161

* Update RDF query stuff again so as to set up a temporary datastore
  each time we want to query over an rdf file, instead of using rasqal
  against the file.  Seems the only way to avoid threading and storage
  management issues when trying to load from a single-source file and
  perform queries against our main datastore at the same time.  Maybe.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

/*
   This is a modified version of a source file from the 
   Rosegarden MIDI and audio sequencer and notation editor.
   This file copyright 2000-2006 Chris Cannam.
*/

#ifndef _REAL_TIME_H_
#define _REAL_TIME_H_

#include <iostream>
#include <string>

struct timeval;


/**
 * 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) { }

    static RealTime fromSeconds(double sec);
    static RealTime fromMilliseconds(int msec);
    static RealTime fromTimeval(const struct timeval &);
    static RealTime fromXsdDuration(std::string xsdd);

    double toDouble() const;

    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 m) const;
    RealTime operator/(int d) const;

    RealTime operator*(double m) const;
    RealTime operator/(double d) const;

    /**
     * Return the ratio of two 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).  If align
     * is true, prepend " " to the start of positive values so that
     * they line up with negative ones (which start with "-").
     */ 
    std::string toString(bool align = false) const;

    /**
     * Convert a string as obtained from toString back to a RealTime
     * object.
     */
    static RealTime fromString(std::string);

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

    /**
     * Return a user-readable string to the nearest second, in a form
     * like "6s" (for less than a minute) or "2:21" (for more).
     */
    std::string toSecText() const;

    /**
     * Convert a RealTime into a sample frame at the given sample rate.
     */
    static long realTime2Frame(const RealTime &r, unsigned int sampleRate);

    /**
     * Convert a sample frame at the given sample rate into a RealTime.
     */
    static RealTime frame2RealTime(long frame, unsigned int sampleRate);

    static const RealTime zeroTime;
};

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