mixer.h
/*
* This file is part of libsidplayfp, a SID player engine.
*
* Copyright 2011-2015 Leandro Nini <drfiemost@users.sourceforge.net>
* Copyright 2007-2010 Antti Lankila
* Copyright (C) 2000 Simon White
*
* 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 MIXER_H
#define MIXER_H
#include <stdint.h>
#include <cstdlib>
#include <vector>
class sidemu;
class Mixer
{
public:
static const unsigned int MAX_SIDS = 3;
static const int_least32_t SCALE_FACTOR = 1 << 16;
static const int_least32_t C1 = static_cast<int_least32_t>(1.0 / (1.0 + 0.7071067812) * SCALE_FACTOR);
static const int_least32_t C2 = static_cast<int_least32_t>(0.7071067812 / (1.0 + 0.7071067812) * SCALE_FACTOR);
private:
typedef int_least32_t (Mixer::*mixer_func_t)() const;
public:
static const int_least32_t VOLUME_MAX = 1024;
private:
std::vector<sidemu*> m_chips;
std::vector<short*> m_buffers;
std::vector<int_least32_t> m_iSamples;
std::vector<int_least32_t> m_volume;
std::vector<mixer_func_t> m_mix;
int oldRandomValue;
int m_fastForwardFactor;
// Mixer settings
short *m_sampleBuffer;
uint_least32_t m_sampleCount;
uint_least32_t m_sampleIndex;
bool m_stereo;
private:
void updateParams();
int triangularDithering()
{
const int prevValue = oldRandomValue;
oldRandomValue = rand() & (VOLUME_MAX-1);
return oldRandomValue - prevValue;
}
/*
* Channel matrix
*
* C1
* L 1.0
* R 1.0
*
* C1 C2
* L 1.0 0.0
* R 0.0 1.0
*
* C1 C2 C3
* L 1/1.707 0.707/1.707 0.0
* R 0.0 0.707/1.707 1/1.707
*/
// Mono mixing
int_least32_t mono_OneChip() const { return m_iSamples[0]; }
int_least32_t mono_TwoChips() const { return (m_iSamples[0] + m_iSamples[1]) / 2; }
int_least32_t mono_ThreeChips() const { return (m_iSamples[0] + m_iSamples[1] + m_iSamples[2]) / 3; }
// Stereo mixing
int_least32_t stereo_OneChip() const { return m_iSamples[0]; }
int_least32_t stereo_ch1_TwoChips() const { return m_iSamples[0]; }
int_least32_t stereo_ch2_TwoChips() const { return m_iSamples[1]; }
int_least32_t stereo_ch1_ThreeChips() const { return (C1*m_iSamples[0] + C2*m_iSamples[1]) / SCALE_FACTOR; }
int_least32_t stereo_ch2_ThreeChips() const { return (C2*m_iSamples[1] + C1*m_iSamples[2]) / SCALE_FACTOR; }
public:
Mixer() :
oldRandomValue(0),
m_fastForwardFactor(1),
m_sampleCount(0),
m_stereo(false)
{
m_mix.push_back(&Mixer::mono_OneChip);
}
void doMix();
void clockChips();
void resetBufs();
void begin(short *buffer, uint_least32_t count);
void clearSids();
void addSid(sidemu *chip);
sidemu* getSid(unsigned int i) const { return (i < m_chips.size()) ? m_chips[i] : 0; }
bool setFastForward(int ff);
void setVolume(int_least32_t left, int_least32_t right);
void setStereo(bool stereo);
bool notFinished() const { return m_sampleIndex != m_sampleCount; }
uint_least32_t samplesGenerated() const { return m_sampleIndex; }
};
#endif // MIXER_H
Mixer::MAX_SIDS
static const unsigned int MAX_SIDS
Maximum number of supported SIDs.
Definition: mixer.h:41
Mixer::clockChips
void clockChips()
Definition: mixer.cpp:59
Mixer::VOLUME_MAX
static const int_least32_t VOLUME_MAX
Maximum allowed volume, must be a power of 2.
Definition: mixer.h:52
Mixer
Definition: mixer.h:37
Mixer::setStereo
void setStereo(bool stereo)
Definition: mixer.cpp:170
sidemu
Definition: sidemu.h:39
Mixer::notFinished
bool notFinished() const
Definition: mixer.h:196
Mixer::setFastForward
bool setFastForward(int ff)
Definition: mixer.cpp:182
Mixer::setVolume
void setVolume(int_least32_t left, int_least32_t right)
Definition: mixer.cpp:191
Mixer::samplesGenerated
uint_least32_t samplesGenerated() const
Definition: mixer.h:201
Mixer::doMix
void doMix()
Definition: mixer.cpp:69
Mixer::Mixer
Mixer()
Definition: mixer.h:118
Mixer::addSid
void addSid(sidemu *chip)
Definition: mixer.cpp:156
Mixer::getSid
sidemu * getSid(unsigned int i) const
Definition: mixer.h:168
Mixer::clearSids
void clearSids()
Definition: mixer.cpp:150
Mixer::begin
void begin(short *buffer, uint_least32_t count)
Definition: mixer.cpp:125
Mixer::resetBufs
void resetBufs()
Definition: mixer.cpp:64