Files
lmms/include/Instrument.h
2015-01-22 16:28:41 +01:00

145 lines
4.3 KiB
C++

/*
* Instrument.h - declaration of class Instrument, which provides a
* standard interface for all instrument plugins
*
* Copyright (c) 2005-2014 Tobias Doerffel <tobydox/at/users.sourceforge.net>
*
* This file is part of LMMS - http://lmms.io
*
* 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 (see COPYING); if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA.
*
*/
#ifndef INSTRUMENT_H
#define INSTRUMENT_H
#include <QString>
#include <QtGlobal>
#include "export.h"
#include "lmms_basics.h"
#include "MemoryManager.h"
#include "MidiTime.h"
#include "Plugin.h"
// forward-declarations
class InstrumentTrack;
class MidiEvent;
class NotePlayHandle;
class Track;
class EXPORT Instrument : public Plugin
{
MM_OPERATORS
public:
enum Flag
{
NoFlags = 0x00,
IsSingleStreamed = 0x01, /*! Instrument provides a single audio stream for all notes */
IsMidiBased = 0x02, /*! Instrument is controlled by MIDI events rather than NotePlayHandles */
IsNotBendable = 0x04, /*! Instrument can't react to pitch bend changes */
};
Q_DECLARE_FLAGS(Flags, Flag);
Instrument( InstrumentTrack * _instrument_track,
const Descriptor * _descriptor );
virtual ~Instrument();
// --------------------------------------------------------------------
// functions that can/should be re-implemented:
// --------------------------------------------------------------------
// if the plugin doesn't play each note, it can create an instrument-
// play-handle and re-implement this method, so that it mixes its
// output buffer only once per mixer-period
virtual void play( sampleFrame * _working_buffer );
// to be implemented by actual plugin
virtual void playNote( NotePlayHandle * /* _note_to_play */,
sampleFrame * /* _working_buf */ )
{
}
// needed for deleting plugin-specific-data of a note - plugin has to
// cast void-ptr so that the plugin-data is deleted properly
// (call of dtor if it's a class etc.)
virtual void deleteNotePluginData( NotePlayHandle * _note_to_play );
// Get number of sample-frames that should be used when playing beat
// (note with unspecified length)
// Per default this function returns 0. In this case, channel is using
// the length of the longest envelope (if one active).
virtual f_cnt_t beatLen( NotePlayHandle * _n ) const;
// some instruments need a certain number of release-frames even
// if no envelope is active - such instruments can re-implement this
// method for returning how many frames they at least like to have for
// release
virtual f_cnt_t desiredReleaseFrames() const
{
return 0;
}
virtual Flags flags() const
{
return NoFlags;
}
// sub-classes can re-implement this for receiving all incoming
// MIDI-events
inline virtual bool handleMidiEvent( const MidiEvent&, const MidiTime& = MidiTime(), f_cnt_t offset = 0 )
{
return true;
}
virtual QString fullDisplayName() const;
// --------------------------------------------------------------------
// provided functions:
// --------------------------------------------------------------------
// instantiate instrument-plugin with given name or return NULL
// on failure
static Instrument * instantiate( const QString & _plugin_name,
InstrumentTrack * _instrument_track );
virtual bool isFromTrack( const Track * _track ) const;
inline InstrumentTrack * instrumentTrack() const
{
return m_instrumentTrack;
}
protected:
// instruments may use this to apply a soft fade out at the end of
// notes - method does this only if really less or equal
// desiredReleaseFrames() frames are left
void applyRelease( sampleFrame * buf, const NotePlayHandle * _n );
private:
InstrumentTrack * m_instrumentTrack;
} ;
Q_DECLARE_OPERATORS_FOR_FLAGS(Instrument::Flags)
#endif