cog/Frameworks/libsidplay/sidplay-residfp-code/.svn/pristine/91/91e380da18e1ed37aa253da5c6e...

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/*
* This file is part of libsidplayfp, a SID player engine.
*
* Copyright 2011-2014 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 "sidcxx11.h"
#include <stdint.h>
#include <cstdlib>
#include <vector>
class sidemu;
/**
* This class implements the mixer.
*/
class Mixer
{
public:
/// Maximum number of supported SIDs (mono and stereo)
static const unsigned int MAX_SIDS = 2;
private:
typedef short (Mixer::*mixer_func_t)() const;
public:
/**
* Maximum allowed volume, must be a power of 2.
*/
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;
}
// Mono mixing
short mono_OneChip() const { return static_cast<short>(m_iSamples[0]); }
short mono_TwoChips() const { return static_cast<short>((m_iSamples[0] + m_iSamples[1]) / 2); }
short mono_ThreeChips() const { return static_cast<short>((m_iSamples[0] + m_iSamples[1] + m_iSamples[2]) / 3); }
// Stereo mixing
short stereo_OneChip() const { return static_cast<short>(m_iSamples[0]); }
short stereo_ch1_TwoChips() const { return static_cast<short>(m_iSamples[0]); }
short stereo_ch2_TwoChips() const { return static_cast<short>(m_iSamples[1]); }
short stereo_ch1_ThreeChips() const { return static_cast<short>((m_iSamples[0] + m_iSamples[1]) / 2); }
short stereo_ch2_ThreeChips() const { return static_cast<short>((m_iSamples[1] + m_iSamples[2]) / 2); }
public:
/**
* Create a new mixer.
*
* @param context event context
*/
Mixer() :
oldRandomValue(0),
m_fastForwardFactor(1),
m_sampleCount(0),
m_stereo(false)
{
m_mix.push_back(&Mixer::mono_OneChip);
}
/**
* Do the mixing.
*/
void doMix();
/**
* This clocks the SIDs to the present moment, if they aren't already.
*/
void clockChips();
/**
* Reset sidemu buffer position discarding produced samples.
*/
void resetBufs();
/**
* Prepare for mixing cycle.
*
* @param buffer output buffer
* @param count size of the buffer in samples
*/
void begin(short *buffer, uint_least32_t count);
/**
* Remove all SIDs from the mixer.
*/
void clearSids();
/**
* Add a SID to the mixer.
*
* @param chip the sid emu to add
*/
void addSid(sidemu *chip);
/**
* Get a SID to the mixer.
*
* @param i the number of the SID to get
* @return a pointer to the requested sid emu or 0 if not found
*/
sidemu* getSid(unsigned int i) const { return (i < m_chips.size()) ? m_chips[i] : nullptr; }
/**
* Set the fast forward ratio.
*
* @param ff the fast forward ratio, from 1 to 32
* @return true if parameter is valid, false otherwise
*/
bool setFastForward(int ff);
/**
* Set mixing volumes, from 0 to #VOLUME_MAX.
*
* @param left volume for left or mono channel
* @param right volume for right channel in stereo mode
*/
void setVolume(int_least32_t left, int_least32_t right);
/**
* Set mixing mode.
*
* @param stereo true for stereo mode, false for mono
*/
void setStereo(bool stereo);
/**
* Check if the buffer have been filled.
*/
bool notFinished() const { return m_sampleIndex != m_sampleCount; }
/**
* Get the number of samples generated up to now.
*/
uint_least32_t samplesGenerated() const { return m_sampleIndex; }
};
#endif // MIXER_H