root/trunk/libjdkmidi/trunk/include/jdkmidi/tempo.h

/*
 *  libjdkmidi-2004 C++ Class Library for MIDI
 *
 *  Copyright (C) 2004  J.D. Koftinoff Software, Ltd.
 *  www.jdkoftinoff.com
 *  jeffk@jdkoftinoff.com
 *
 *  *** RELEASED UNDER THE GNU GENERAL PUBLIC LICENSE (GPL) April 27, 2004 ***
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
/*
** Copyright 1986 to 1998 By J.D. Koftinoff Software, Ltd.
**
** All rights reserved.
**
** No one may duplicate this source code in any form for any reason
** without the written permission given by J.D. Koftinoff Software, Ltd.
**
*/

#ifndef JDKMIDI_TEMPO_H
#define JDKMIDI_TEMPO_H

//
// This class makes it easy to deal with Tempos as fixed point
// numbers.
//
// The actual tempo is stored times 256 for 1/256 bpm accuracy.
//
// The default operator int() etc., automatically convert the
// fixed point number so the value is in normal beats per minutes.
//
//

#include "jdkmidi/midi.h"

namespace jdkmidi
{

  class  MIDITempo
  {
    public:
      MIDITempo()
      {
        tempo=120<<8;
      }
      MIDITempo ( int a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      MIDITempo ( unsigned int a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      MIDITempo ( long a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      MIDITempo ( unsigned long a )
      {
        tempo=a << 8;
      }
      MIDITempo ( float a )
      {
        tempo= ( unsigned long ) ( a*256.0 );
      }
      MIDITempo ( const MIDITempo &a )
      {
        tempo=a.GetFullTempo();
      }
      
      operator short ()
      {
        return ( short ) ( ( tempo+0x80 ) >>8 );
      }
      operator unsigned short ()
      {
        return ( unsigned short ) ( ( tempo+0x80 ) >>8 );
      }
      
      operator int ()
      {
        return ( int ) ( ( tempo+0x80 ) >>8 );
      }
      operator unsigned int ()
      {
        return ( unsigned int ) ( ( tempo+0x80 ) >>8 );
      }
      operator long ()
      {
        return ( long ) ( ( tempo+0x80 ) >>8 );
      }
      operator unsigned long ()
      {
        return ( unsigned long ) ( ( tempo+0x80 ) >>8 );
      }
      operator float ()
      {
        return ( float ) tempo / 256.0f;
      }
      void operator = ( unsigned short a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      void operator = ( short a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      
      void operator = ( unsigned int a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      void operator = ( int a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      void operator = ( unsigned long a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      void operator = ( long a )
      {
        tempo= ( unsigned long ) a << 8;
      }
      
      void operator = ( float a )
      {
        tempo= ( unsigned long ) ( a*256.0 );
      }
      
      unsigned long GetFullTempo() const
      {
        return tempo;
      }
      void SetFullTempo ( unsigned long v )
      {
        tempo=v;
      }
      
      unsigned long GetMIDIFileTempo()
      {
        if ( tempo ) return ( 60000000L/256 ) /tempo;
        else
          return ( 60000000L/256 ) / ( 120*256 );
      }
      
    protected:
      unsigned long tempo;
  };
  
}

#endif