annotate base/RealTime.cpp @ 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.
*/

#include <iostream>

#if (__GNUC__ < 3)
#include <strstream>
#define stringstream strstream
#else
#include <sstream>
#endif

using std::cerr;
using std::endl;

#include "base/RealTime.h"

// A RealTime consists of two ints that must be at least 32 bits each.
// A signed 32-bit int can store values exceeding +/- 2 billion.  This
// means we can safely use our lower int for nanoseconds, as there are
// 1 billion nanoseconds in a second and we need to handle double that
// because of the implementations of addition etc that we use.
//
// The maximum valid RealTime on a 32-bit system is somewhere around
// 68 years: 999999999 nanoseconds longer than the classic Unix epoch.

#define ONE_BILLION 1000000000

RealTime::RealTime(int s, int n) :
    sec(s), nsec(n)
{
    if (sec == 0) {
	while (nsec <= -ONE_BILLION) { nsec += ONE_BILLION; --sec; }
	while (nsec >=  ONE_BILLION) { nsec -= ONE_BILLION; ++sec; }
    } else if (sec < 0) {
	while (nsec <= -ONE_BILLION) { nsec += ONE_BILLION; --sec; }
	while (nsec > 0)             { nsec -= ONE_BILLION; ++sec; }
    } else { 
	while (nsec >=  ONE_BILLION) { nsec -= ONE_BILLION; ++sec; }
	while (nsec < 0)             { nsec += ONE_BILLION; --sec; }
    }
}


std::ostream &operator<<(std::ostream &out, const RealTime &rt)
{
    if (rt < RealTime::zeroTime) {
	out << "-";
    } else {
	out << " ";
    }

    int s = (rt.sec < 0 ? -rt.sec : rt.sec);
    int n = (rt.nsec < 0 ? -rt.nsec : rt.nsec);

    out << s << ".";

    int nn(n);
    if (nn == 0) out << "00000000";
    else while (nn < (ONE_BILLION / 10)) {
	out << "0";
	nn *= 10;
    }
    
    out << n << "R";
    return out;
}

std::string
RealTime::toString() const
{
    std::stringstream out;
    out << *this;
    
#if (__GNUC__ < 3)
    out << std::ends;
#endif

    std::string s = out.str();

    // remove trailing R
    return s.substr(0, s.length() - 1);
}

std::string
RealTime::toText(bool fixedDp) const
{
    if (*this < RealTime::zeroTime) return "-" + (-*this).toText();

    std::stringstream out;

    if (sec >= 3600) {
	out << (sec / 3600) << ":";
    }

    if (sec >= 60) {
	out << (sec % 3600) / 60 << ":";
    }

    if (sec >= 10) {
	out << ((sec % 60) / 10);
    }

    out << (sec % 10);
    
    int ms = msec();

    if (ms != 0) {
	out << ".";
	out << (ms / 100);
	ms = ms % 100;
	if (ms != 0) {
	    out << (ms / 10);
	    ms = ms % 10;
	} else if (fixedDp) {
	    out << "0";
	}
	if (ms != 0) {
	    out << ms;
	} else if (fixedDp) {
	    out << "0";
	}
    } else if (fixedDp) {
	out << ".000";
    }
	
#if (__GNUC__ < 3)
    out << std::ends;
#endif

    std::string s = out.str();

    return s;
}


RealTime
RealTime::operator/(int d) const
{
    int secdiv = sec / d;
    int secrem = sec % d;

    double nsecdiv = (double(nsec) + ONE_BILLION * double(secrem)) / d;
    
    return RealTime(secdiv, int(nsecdiv + 0.5));
}

double 
RealTime::operator/(const RealTime &r) const
{
    double lTotal = double(sec) * ONE_BILLION + double(nsec);
    double rTotal = double(r.sec) * ONE_BILLION + double(r.nsec);
    
    if (rTotal == 0) return 0.0;
    else return lTotal/rTotal;
}

long
RealTime::realTime2Frame(const RealTime &time, unsigned int sampleRate)
{
    if (time < zeroTime) return -realTime2Frame(-time, sampleRate);

    // We like integers.  The last term is always zero unless the
    // sample rate is greater than 1MHz, but hell, you never know...

    long frame =
	time.sec * sampleRate +
	(time.msec() * sampleRate) / 1000 +
	((time.usec() - 1000 * time.msec()) * sampleRate) / 1000000 +
	((time.nsec - 1000 * time.usec()) * sampleRate) / 1000000000;

    return frame;
}

RealTime
RealTime::frame2RealTime(long frame, unsigned int sampleRate)
{
    if (frame < 0) return -frame2RealTime(-frame, sampleRate);

    RealTime rt;
    rt.sec = frame / long(sampleRate);
    frame -= rt.sec * long(sampleRate);
    rt.nsec = (int)(((float(frame) * 1000000) / long(sampleRate)) * 1000);
    return rt;
}

const RealTime RealTime::zeroTime(0,0);