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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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 TOWNS_PC98_FMSYNTH_H
#define TOWNS_PC98_FMSYNTH_H
#include "audio/audiostream.h"
#include "audio/mixer.h"
#include "common/mutex.h"
#include "common/func.h"
#include "common/array.h"
#ifdef __DS__
/* This disables the rhythm channel when emulating the PC-98 type 86 sound card.
* The only purpose is code size reduction for certain backends.
* At the moment the only games which make use of the rhythm channel are the
* (very rare) PC-98 versions of Legend of Kyrandia 2 and Lands of Lore. Music will
* still be okay, just missing a couple of rhythm instruments.
*/
#define DISABLE_PC98_RHYTHM_CHANNEL
#endif
/* Experimental code for emulation of the chip's busy flag wait cycle.
* Explanation:
* Before attempting a port write a client application would usually read the chip's
* busy flag and remain in a loop until the flag is cleared. This does not work with
* an emulator that is on the same thread as the client code (the busy flag will never
* clear). Instead, I emulate a wait cycle by withholding (enqueueing) incoming register
* writes for the duration of the wait cycle.
* For now I have disabled this with an #ifdef since I haven't seen any impact on the
* sound.
*/
//#define ENABLE_SNDTOWNS98_WAITCYCLES
class TownsPC98_FmSynthOperator;
class TownsPC98_FmSynthSquareWaveSource;
#ifndef DISABLE_PC98_RHYTHM_CHANNEL
class TownsPC98_FmSynthPercussionSource;
#endif
enum EnvelopeState {
kEnvReady = 0,
kEnvAttacking,
kEnvDecaying,
kEnvSustaining,
kEnvReleasing
};
class TownsPC98_FmSynth : public Audio::AudioStream {
public:
enum EmuType {
kTypeTowns = 0,
kType26 = 1,
kType86 = 2
};
TownsPC98_FmSynth(Audio::Mixer *mixer, EmuType type);
virtual ~TownsPC98_FmSynth();
virtual bool init();
virtual void reset();
void writeReg(uint8 part, uint8 regAddress, uint8 value);
uint8 readReg(uint8 part, uint8 regAddress);
// AudioStream interface
int readBuffer(int16 *buffer, const int numSamples);
bool isStereo() const;
bool endOfData() const;
int getRate() const;
protected:
void deinit();
// Implement this in your inherited class if your driver generates
// additional output that has to be inserted into the buffer.
virtual void nextTickEx(int32 *buffer, uint32 bufferSize) {}
virtual void timerCallbackA() = 0;
virtual void timerCallbackB() = 0;
// The audio driver can store and apply two different volume settings
// (usually for music and sound effects). The channel mask will determine
// which channels get effected by which setting. The first bits will be
// the normal fm channels, the next bits the ssg channels and the final
// bit the rhythm channel.
void setVolumeIntern(int volA, int volB);
void setVolumeChannelMasks(int channelMaskA, int channelMaskB);
// This allows to balance out the fm/ssg levels.
void setLevelSSG(int vol);
const int _numChan;
const int _numSSG;
const bool _hasPercussion;
Common::Mutex _mutex;
private:
void generateTables();
void writeRegInternal(uint8 part, uint8 regAddress, uint8 value);
void nextTick(int32 *buffer, uint32 bufferSize);
#ifdef ENABLE_SNDTOWNS98_WAITCYCLES
void startWaitCycle();
#endif
struct ChanInternal {
ChanInternal();
~ChanInternal();
void ampModSensitivity(uint32 value) {
ampModSvty = (1 << (3 - value)) - (((value >> 1) & 1) | (value & 1));
}
void frqModSensitivity(uint32 value) {
frqModSvty = value << 5;
}
void fbClear() {
feedbuf[0] = feedbuf[1] = feedbuf[2] = 0;
}
bool enableLeft;
bool enableRight;
bool updateEnvelopeParameters;
int32 feedbuf[3];
uint8 algorithm;
uint32 ampModSvty;
uint32 frqModSvty;
TownsPC98_FmSynthOperator *opr[4];
};
TownsPC98_FmSynthSquareWaveSource *_ssg;
#ifndef DISABLE_PC98_RHYTHM_CHANNEL
TownsPC98_FmSynthPercussionSource *_prc;
#endif
ChanInternal *_chanInternal;
uint8 *_oprRates;
uint8 *_oprRateshift;
uint8 *_oprAttackDecay;
uint32 *_oprFrq;
uint32 *_oprSinTbl;
int32 *_oprLevelOut;
int32 *_oprDetune;
typedef Common::Functor0Mem<void, TownsPC98_FmSynth> ChipTimerProc;
ChipTimerProc *_timerProcIdle;
ChipTimerProc *_timerProcA;
ChipTimerProc *_timerProcB;
void idleTimerCallback() {}
struct ChipTimer {
bool enabled;
uint16 value;
int32 smpTillCb;
uint32 smpTillCbRem;
int32 smpPerCb;
uint32 smpPerCbRem;
ChipTimerProc *cb;
};
ChipTimer _timers[2];
int _volMaskA, _volMaskB;
uint16 _volumeA, _volumeB;
int32 *_renderBuffer;
int _renderBufferSize;
int _numPending;
int _offsPending;
int _rateScale;
int _outRateMult;
int _rateConvCnt;
float _predSmpCount;
const int _internalRate;
const int _outputRate;
#ifdef ENABLE_SNDTOWNS98_WAITCYCLES
int _waitCycleRemainder;
const int _samplesPerWaitCycle;
struct RegEntry {
RegEntry(uint8 p, uint8 r, uint8 v) : part(p), reg(r), val(v) {}
uint8 part;
uint8 reg;
uint8 val;
};
Common::Array<RegEntry> _waitCycleElapsedWrites;
#endif
uint8 _registers[255][2];
Audio::Mixer *_mixer;
Audio::SoundHandle _soundHandle;
#ifndef DISABLE_PC98_RHYTHM_CHANNEL
static const uint8 _percussionData[];
#endif
static const uint32 _adtStat[];
static const uint8 _detSrc[];
static const int _ssgTables[];
bool _ready;
};
#endif
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