furnace/src/engine/platform/c64.h

/**
 * Furnace Tracker - multi-system chiptune tracker
 * Copyright (C) 2021-2025 tildearrow and contributors
 *
 * 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 _C64_H
#define _C64_H

#include "../dispatch.h"
#include "../../fixedQueue.h"
#include "sound/c64/sid.h"
#include "sound/c64_fp/SID.h"
#include "sound/c64_d/dsid.h"

// TODO:
// - ex3 (special) unify with ex4 (gate/test)
// - ex4 (test) compatibility

class DivPlatformC64: public DivDispatch {
  struct Channel: public SharedChannel<signed char> {
    int prevFreq, testWhen;
    unsigned int audPos;
    int pcmPos, sample, pcmPeriod, pcmRate, pcmOut;
    unsigned char sweep, wave, attack, decay, sustain, release;
    short duty;
    bool sweepChanged, filter, setPos, pcm;
    bool resetMask, resetFilter, resetDuty, gate, ring, sync, test;
    short pw_slide;
    Channel():
      SharedChannel<signed char>(15),
      prevFreq(65535),
      testWhen(0),
      audPos(0),
      pcmPos(0),
      sample(-1),
      pcmPeriod(0),
      pcmRate(0),
      pcmOut(15),
      sweep(0),
      wave(0),
      attack(0),
      decay(0),
      sustain(0),
      release(0),
      duty(0),
      sweepChanged(false),
      filter(false),
      setPos(false),
      pcm(false),
      resetMask(false),
      resetFilter(false),
      resetDuty(false),
      gate(true),
      ring(false),
      sync(false),
      test(false),
      pw_slide(0) {}
  };
  Channel chan[4];
  DivDispatchOscBuffer* oscBuf[4];
  bool isMuted[4];
  float fakeLow[4];
  float fakeBand[4];
  float fakeCutTable[2048];
  struct QueuedWrite {
      unsigned char addr;
      unsigned char val;
      QueuedWrite(): addr(0), val(0) {}
      QueuedWrite(unsigned char a, unsigned char v): addr(a), val(v) {}
  };
  FixedQueue<QueuedWrite,128> writes;

  unsigned char filtControl, filtRes, vol;
  unsigned char writeOscBuf;
  unsigned char sidCore;
  int filtCut, resetTime, initResetTime;
  int pcmCycle, lineRate;
  short cutoff_slide;

  bool keyPriority, sidIs6581, needInitTables, no1EUpdate, multiplyRel, macroRace, noSoftPCM;
  unsigned char chanOrder[3];
  unsigned char testAD, testSR;

  SID* sid;
  reSIDfp::SID* sid_fp;
  struct SID_chip* sid_d;
  int coreQuality;
  unsigned char regPool[32];
  
  friend void putDispatchChip(void*,int);
  friend void putDispatchChan(void*,int,int);

  inline short runFakeFilter(unsigned char ch, int in);

  void processDAC(int sRate);
  void acquire_classic(short* bufL, short* bufR, size_t start, size_t len);
  void acquire_fp(short* bufL, short* bufR, size_t start, size_t len);

  void updateFilter();
  void updateVolume();
  public:
    void acquire(short** buf, size_t len);
    int dispatch(DivCommand c);
    void* getChanState(int chan);
    DivDispatchOscBuffer* getOscBuffer(int chan);
    unsigned char* getRegisterPool();
    int getRegisterPoolSize();
    void reset();
    void forceIns();
    void tick(bool sysTick=true);
    void muteChannel(int ch, bool mute);
    void setFlags(const DivConfig& flags);
    void notifyInsChange(int ins);
    bool getDCOffRequired();
    bool getWantPreNote();
    bool isVolGlobal();
    float getPostAmp();
    DivMacroInt* getChanMacroInt(int ch);
    void getPaired(int ch, std::vector<DivChannelPair>& ret);
    DivChannelModeHints getModeHints(int chan);
    void notifyInsDeletion(void* ins);
    void poke(unsigned int addr, unsigned short val);
    void poke(std::vector<DivRegWrite>& wlist);
    const char** getRegisterSheet();
    int init(DivEngine* parent, int channels, int sugRate, const DivConfig& flags);
    void setChipModel(bool is6581);
    void setCore(unsigned char which);
    void setCoreQuality(unsigned char q);
    void setSoftPCM(bool isSoft);
    void quit();
    ~DivPlatformC64();
};

#endif