Filter6581.h

/*
 * This file is part of libsidplayfp, a SID player engine.
 *
 * Copyright 2011-2013 Leandro Nini <drfiemost@users.sourceforge.net>
 * Copyright 2007-2010 Antti Lankila
 * Copyright 2004,2010 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 FILTER6581_H
#define FILTER6581_H
 
#include "siddefs-fp.h"
 
#include <memory>
 
#include "Filter.h"
#include "FilterModelConfig.h"
 
namespace reSIDfp
{
 
class Integrator;
 
class Filter6581 : public Filter
{
private:
    unsigned short* currentGain;
 
    unsigned short* currentMixer;
 
    unsigned short* currentSummer;
 
    unsigned short* currentResonance;
 
    const unsigned short* f0_dac;
 
    unsigned short** mixer;
    unsigned short** summer;
    unsigned short** gain;
 
    int Vhp;
 
    int Vbp;
 
    int Vlp;
 
    int ve;
 
    const int voiceScaleS14;
    const int voiceDC;
 
    std::auto_ptr<Integrator> hpIntegrator;
 
    std::auto_ptr<Integrator> bpIntegrator;
 
public:
    Filter6581() :
        currentGain(0),
        currentMixer(0),
        currentSummer(0),
        currentResonance(0),
        f0_dac(FilterModelConfig::getInstance()->getDAC(0.5)),
        mixer(FilterModelConfig::getInstance()->getMixer()),
        summer(FilterModelConfig::getInstance()->getSummer()),
        gain(FilterModelConfig::getInstance()->getGain()),
        Vhp(0),
        Vbp(0),
        Vlp(0),
        ve(0),
        voiceScaleS14(FilterModelConfig::getInstance()->getVoiceScaleS14()),
        voiceDC(FilterModelConfig::getInstance()->getVoiceDC()),
        hpIntegrator(FilterModelConfig::getInstance()->buildIntegrator()),
        bpIntegrator(FilterModelConfig::getInstance()->buildIntegrator())
    {
        input(0);
    }
 
    ~Filter6581();
 
    int clock(int voice1, int voice2, int voice3);
 
    void input(int sample) { ve = (sample * voiceScaleS14 * 3 >> 10) + mixer[0][0]; }
 
    void updatedCenterFrequency();
 
    void updatedResonance() { currentResonance = gain[~res & 0xf]; }
 
    void updatedMixing();
 
public:
    void setFilterCurve(double curvePosition);
};
 
} // namespace reSIDfp
 
#if RESID_INLINING || defined(FILTER6581_CPP)
 
#include "Integrator.h"
 
namespace reSIDfp
{
 
RESID_INLINE
int Filter6581::clock(int voice1, int voice2, int voice3)
{
    voice1 = (voice1 * voiceScaleS14 >> 18) + voiceDC;
    voice2 = (voice2 * voiceScaleS14 >> 18) + voiceDC;
    voice3 = (voice3 * voiceScaleS14 >> 18) + voiceDC;
 
    int Vi = 0;
    int Vo = 0;
 
    (filt1 ? Vi : Vo) += voice1;
 
    (filt2 ? Vi : Vo) += voice2;
 
    // NB! Voice 3 is not silenced by voice3off if it is routed
    // through the filter.
    if (filt3)
    {
        Vi += voice3;
    }
    else if (!voice3off)
    {
        Vo += voice3;
    }
 
    (filtE ? Vi : Vo) += ve;
 
    const int oldVhp = Vhp;
    Vhp = currentSummer[currentResonance[Vbp] + Vlp + Vi];
    Vlp = bpIntegrator->solve(Vbp);
    Vbp = hpIntegrator->solve(oldVhp);
 
    if (lp)
    {
        Vo += Vlp;
    }
 
    if (bp)
    {
        Vo += Vbp;
    }
 
    if (hp)
    {
        Vo += Vhp;
    }
 
    return currentGain[currentMixer[Vo]] - (1 << 15);
}
 
} // namespace reSIDfp
 
#endif
 
#endif