SID.h

/*
 * This file is part of libsidplayfp, a SID player engine.
 *
 * Copyright 2011-2026 Leandro Nini <drfiemost@users.sourceforge.net>
 * Copyright 2007-2010 Antti Lankila
 * Copyright 2004 Dag Lem <resid@nimrod.no>
 *
 * 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 SIDFP_H
#define SIDFP_H
 
#include <memory>
#include <cstdint>
 
#include "residfp/residfp_defs.h"
#include "siddefs-fp.h"
#include "ExternalFilter.h"
#include "Voice.h"
 
namespace reSIDfp
{
 
class Filter;
class Filter6581;
class Filter8580;
class Resampler;
 
class SIDError
{
private:
    const char* message;
 
public:
    SIDError(const char* msg) :
        message(msg) {}
    const char* getMessage() const { return message; }
};
 
class SID
{
private:
    Filter* filter;
 
    Filter6581* const filter6581;
 
    Filter8580* const filter8580;
 
    std::unique_ptr<Resampler> resampler;
 
    ExternalFilter externalFilter;
 
    Voice voice[3];
 
    int scaleFactor;
 
    int busValueTtl;
 
    int modelTTL;
 
    unsigned int nextVoiceSync;
 
    ChipModel model;
 
    CombinedWaveforms cws;
 
    unsigned char busValue;
 
    float envDAC[256];
 
    float oscDAC[4096];
 
private:
    void ageBusValue(unsigned int n);
 
    void voiceSync(bool sync);
 
public:
    SID();
    ~SID();
 
    void setChipModel(ChipModel model);
 
    ChipModel getChipModel() const { return model; }
 
    void setCombinedWaveforms(CombinedWaveforms cws);
 
    void reset();
 
    void input(int value);
 
    unsigned char read(int offset);
 
    void write(int offset, unsigned char value);
 
    void setSamplingParameters(
        double clockFrequency,
        SamplingMethod method,
        double samplingFrequency
    );
 
    int clock(unsigned int cycles, short* buf);
 
    void clockSilent(unsigned int cycles);
 
    void setFilter6581Curve(double filterCurve);
 
    void setFilter6581Range ( double adjustment );
 
    void setFilter8580Curve(double filterCurve);
 
    void enableFilter(bool enable);
};
 
} // namespace reSIDfp
 
#if RESIDFP_INLINING || defined(SID_CPP)
 
#include <algorithm>
 
#include "Filter.h"
#include "resample/Resampler.h"
 
namespace reSIDfp
{
 
RESIDFP_INLINE
void SID::ageBusValue(unsigned int n)
{
    if (likely(busValueTtl != 0))
    {
        busValueTtl -= n;
 
        if (unlikely(busValueTtl <= 0))
        {
            busValue = 0;
            busValueTtl = 0;
        }
    }
}
 
RESIDFP_INLINE
int SID::clock(unsigned int cycles, short* buf)
{
    ageBusValue(cycles);
    int s = 0;
 
    while (cycles != 0)
    {
        unsigned int delta_t = std::min(nextVoiceSync, cycles);
 
        if (likely(delta_t > 0))
        {
            for (unsigned int i = 0; i < delta_t; i++)
            {
                // clock waveform generators
                voice[0].wave()->clock();
                voice[1].wave()->clock();
                voice[2].wave()->clock();
 
                // clock envelope generators
                voice[0].envelope()->clock();
                voice[1].envelope()->clock();
                voice[2].envelope()->clock();
 
                const int sidOutput = static_cast<int>(filter->clock(voice[0], voice[1], voice[2]));
                const int c64Output = externalFilter.clock(sidOutput + INT16_MIN);
                if (unlikely(resampler->input(c64Output)))
                {
                    buf[s++] = resampler->getOutput(scaleFactor);
                }
            }
 
            cycles -= delta_t;
            nextVoiceSync -= delta_t;
        }
 
        if (unlikely(nextVoiceSync == 0))
        {
            voiceSync(true);
        }
    }
 
    return s;
}
 
} // namespace reSIDfp
 
#endif
 
#endif