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 <cassert>
#include <cstdint>

#include "residfp/residfp_defs.h"
#include "siddefs-fp.h"
#include "ExternalFilter.h"
#include "Filter.h"
#include "Voice.h"
#include "State.h"

namespace reSIDfp
{

class Filter;
class Filter6581;
class Filter8580;
class Resampler;

class SIDError
{
private:
    const char* message;

public:
    explicit SIDError(const char* msg) :
        message(msg) {}
    const char* getMessage() const { return message; }
};

class SID
{
    friend class State;

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;

    unsigned int offset_6581;

    ChipModel model;

    CombinedWaveforms cws;

    // Dac leakage
    double dacLeakage;

    uint8_t busValue;


    uint8_t paddleX = 0xff;
    uint8_t paddleY = 0xff;

    float envDAC[256];

    float oscDAC[4096];

    Params* p;

private:
    void ageBusValue(int n);

    void voiceSync(bool sync);

    inline void clockWaveGen()
    {
        voice[0].wave()->clock();
        voice[1].wave()->clock();
        voice[2].wave()->clock();
    }

    inline void clockEnvGen()
    {
        voice[0].envelope()->clock();
        voice[1].envelope()->clock();
        voice[2].envelope()->clock();
    }

    inline int32_t clockFilt()
    {
        uint16_t filtOutput = filter->clock(voice[0], voice[1], voice[2]);
        int32_t exFiltInput = static_cast<int32_t>(filtOutput) + INT16_MIN;
        return externalFilter.clock(exFiltInput);
    }

private:
    SID(const SID&) = delete;
    SID& operator=(const SID&) = delete;

public:
    SID();
    ~SID();

    void setChipModel(ChipModel model);

    ChipModel getChipModel() const { return model; }

    void setCombinedWaveforms(CombinedWaveforms cws);

    void reset();

    void input(int value);

    uint8_t peek(int offset) const;

    uint8_t read(int offset);

    void write(int offset, uint8_t value);

    void setSamplingParameters(
        double clockFrequency,
        SamplingMethod method,
        double samplingFrequency
    );

    int clock(unsigned int cycles, int16_t* buf);

    int clock(int16_t* buf, int bufSize);

    void clockDigital(unsigned int cycles);

    void clockSilent(unsigned int cycles);

    void setFilter6581Curve(double filterCurve);

    void setFilter6581Range(double adjustment);

    void setFilter8580Curve(double filterCurve);

    void enableFilter(bool enable);

    void enableOld6581caps(bool enable);

    void setPaddle(uint8_t x, uint8_t y);

    /*
     * Set the DAC leakage level.
     */
    void setDacLeakage(double level);

    /*
     * Set the 6581 wave offset.
     */
    void setOffset6581(double offset);

    /*
     * Set the DC-Blocker resistance.
     */
    void setDCBRes(double res);
};

} // namespace reSIDfp

#if RESIDFP_INLINING || defined(SID_CPP)

#include <algorithm>

#include "resample/Resampler.h"

namespace reSIDfp
{

RESIDFP_INLINE
void SID::ageBusValue(int n)
{
    if (likely(busValueTtl != 0))
    {
        busValueTtl -= n;

        if (unlikely(busValueTtl <= 0))
        {
            busValue = 0;
            busValueTtl = 0;
        }
    }
}

RESIDFP_INLINE
int SID::clock(unsigned int cycles, int16_t* buf)
{
    assert(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++)
            {
                clockWaveGen();
                clockEnvGen();

                int32_t output = clockFilt();
                if (unlikely(resampler->input(output)))
                {
                    buf[s++] = resampler->getOutput(scaleFactor);
                }
            }

            cycles -= delta_t;
            nextVoiceSync -= delta_t;
        }

        if (unlikely(nextVoiceSync == 0))
        {
            voiceSync(true);
        }
    }

    return s;
}

RESIDFP_INLINE
int SID::clock(int16_t* buf, int bufSize)
{
    assert(buf);
    assert(bufSize > 0);

    int cycles = 0;

    for (int s = 0; s < bufSize;)
    {
        unsigned int delta_t = nextVoiceSync;

        if (likely(delta_t > 0))
        {
            unsigned int i = 0;
            do
            {
                i++;
                clockWaveGen();
                clockEnvGen();

                int32_t output = clockFilt();
                if (unlikely(resampler->input(output)))
                {
                    buf[s++] = resampler->getOutput(scaleFactor);
                    if (unlikely(s == bufSize))
                    {
                        break;
                    }
                }
            }
            while (i < delta_t);

            cycles += i;
            nextVoiceSync -= i;
        }

        if (likely(nextVoiceSync == 0))
        {
            voiceSync(true);
        }
    }

    ageBusValue(cycles);

    return cycles;
}

} // namespace reSIDfp

#endif

#endif