Windows2003-3790/multimedia/directx/dmusic/dmstyle/timesig.h
2020-09-30 16:53:55 +02:00

181 lines
3.7 KiB
C++

//+-------------------------------------------------------------------------
//
// Microsoft Windows
//
// Copyright (c) 1998-1999 Microsoft Corporation
//
// File: timesig.h
//
//--------------------------------------------------------------------------
// TimeSig.h : time signature stuff
#ifndef __TIME_CONVERT__
#define __TIME_CONVERT__
#include "dmusici.h"
#include "dmusicf.h"
#include "score.h"
#include "debug.h"
struct DirectMusicTimeSig
{
// Time signatures define how many beats per measure, which note receives
// the beat, and the grid resolution.
DirectMusicTimeSig() : m_bBeatsPerMeasure(0), m_bBeat(0), m_wGridsPerBeat(0) { }
DirectMusicTimeSig(BYTE bBPM, BYTE bBeat, WORD wGPB) :
m_bBeatsPerMeasure(bBPM),
m_bBeat(bBeat),
m_wGridsPerBeat(wGPB)
{ }
DirectMusicTimeSig(DMUS_TIMESIGNATURE& TSE) :
m_bBeatsPerMeasure(TSE.bBeatsPerMeasure),
m_bBeat(TSE.bBeat),
m_wGridsPerBeat(TSE.wGridsPerBeat)
{ }
operator DMUS_TIMESIGNATURE()
{
DMUS_TIMESIGNATURE TSE;
TSE.bBeatsPerMeasure = m_bBeatsPerMeasure;
TSE.bBeat = m_bBeat;
TSE.wGridsPerBeat = m_wGridsPerBeat;
TSE.mtTime = 0;
return TSE;
}
MUSIC_TIME ClocksPerBeat()
{
if (m_bBeat)
{
return DMUS_PPQ * 4 / m_bBeat;
}
else
{
return 0;
}
}
MUSIC_TIME FloorBeat(MUSIC_TIME mtTime)
{ MUSIC_TIME mtOneBeat = ClocksPerBeat();
return (!mtOneBeat || mtTime < mtOneBeat) ? 0 : (mtTime - (mtTime % mtOneBeat));
}
MUSIC_TIME CeilingBeat(MUSIC_TIME mtTime)
{ return OnBeat(mtTime) ? mtTime : (FloorBeat(mtTime) + ClocksPerBeat());
}
BOOL OnBeat(MUSIC_TIME mtTime)
{ MUSIC_TIME mtOneBeat = ClocksPerBeat();
return (!mtOneBeat) ? FALSE : !(mtTime % mtOneBeat);
}
MUSIC_TIME GridsToMeasure(WORD wGrid)
{
if (m_wGridsPerBeat && m_bBeatsPerMeasure)
{
return (wGrid / m_wGridsPerBeat) / m_bBeatsPerMeasure;
}
else
{
return 0;
}
}
MUSIC_TIME GridsToBeat(WORD wGrid)
{
if (m_wGridsPerBeat && m_bBeatsPerMeasure)
{
return (wGrid / m_wGridsPerBeat) % m_bBeatsPerMeasure;
}
else
{
return 0;
}
}
MUSIC_TIME GridOffset(WORD wGrid)
{
if (m_wGridsPerBeat)
{
return wGrid - ((wGrid / m_wGridsPerBeat) * m_wGridsPerBeat);
}
else
{
return 0;
}
}
MUSIC_TIME ClocksPerGrid()
{
if (m_wGridsPerBeat)
{
return ClocksPerBeat() / m_wGridsPerBeat;
}
else
{
return 0;
}
}
MUSIC_TIME ClocksPerMeasure()
{
return ClocksPerBeat() * m_bBeatsPerMeasure;
}
MUSIC_TIME ClocksToMeasure(DWORD dwTotalClocks)
{
MUSIC_TIME mtCPM = ClocksPerMeasure();
if (mtCPM)
{
return (dwTotalClocks / mtCPM);
}
else
{
return 0;
}
}
MUSIC_TIME ClocksToBeat(DWORD dwTotalClocks)
{
MUSIC_TIME mtCPB = ClocksPerBeat();
if (mtCPB)
{
return dwTotalClocks / mtCPB;
}
else
{
return 0;
}
}
MUSIC_TIME MeasureAndBeatToClocks(WORD wMeasure, BYTE bBeat)
{
return ClocksPerMeasure() * wMeasure + (ClocksPerBeat() * bBeat);
}
MUSIC_TIME GridToClocks(WORD wGrid)
{
if (m_wGridsPerBeat)
{
return (ClocksPerBeat() * (wGrid / m_wGridsPerBeat)) + (ClocksPerGrid() * (wGrid % m_wGridsPerBeat));
}
else
{
return ClocksPerGrid() * wGrid;
}
}
BYTE m_bBeatsPerMeasure; // beats per measure (top of time sig)
BYTE m_bBeat; // what note receives the beat (bottom of time sig.)
// we can assume that 0 means 256th note
WORD m_wGridsPerBeat; // grids per beat
};
// Convert old clocks to new clocks
template <class T>
inline T ConvertTime(T oldTime)
{ return (T)((DMUS_PPQ / PPQN) * oldTime); }
#endif