scummvm/audio/softsynth/pcspk.h
2011-05-12 01:16:22 +02:00

85 lines
2.3 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef SOUND_SOFTSYNTH_PCSPK_H
#define SOUND_SOFTSYNTH_PCSPK_H
#include "audio/audiostream.h"
#include "common/mutex.h"
namespace Audio {
class PCSpeaker : public AudioStream {
public:
enum WaveForm {
kWaveFormSquare = 0,
kWaveFormSine,
kWaveFormSaw,
kWaveFormTriangle
};
PCSpeaker(int rate = 44100);
~PCSpeaker();
/** Play a note for length ms.
*
* If length is negative, play until told to stop.
*/
void play(WaveForm wave, int freq, int32 length);
/** Stop the currently playing note after delay ms. */
void stop(int32 delay = 0);
/** Adjust the volume. */
void setVolume(byte volume);
bool isPlaying() const;
int readBuffer(int16 *buffer, const int numSamples);
bool isStereo() const { return false; }
bool endOfData() const { return false; }
bool endOfStream() const { return false; }
int getRate() const { return _rate; }
protected:
Common::Mutex _mutex;
int _rate;
WaveForm _wave;
bool _playForever;
uint32 _oscLength;
uint32 _oscSamples;
uint32 _remainingSamples;
uint32 _mixedSamples;
byte _volume;
typedef int8 (*generatorFunc)(uint32, uint32);
static const generatorFunc generateWave[];
static int8 generateSquare(uint32 x, uint32 oscLength);
static int8 generateSine(uint32 x, uint32 oscLength);
static int8 generateSaw(uint32 x, uint32 oscLength);
static int8 generateTriangle(uint32 x, uint32 oscLength);
};
} // End of namespace Audio
#endif // SOUND_SOFTSYNTH_PCSPEAKER_H