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qzdoom/libraries/oplsynth/OPL3.cpp
Christoph Oelckers d3df422031 - made the OPL synth backend a separate library.
2019-09-26 20:06:39 +02:00

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/*
* File: OPL3.java
* Software implementation of the Yamaha YMF262 sound generator.
* Copyright (C) 2008 Robson Cozendey <robson@cozendey.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* One of the objectives of this emulator is to stimulate further research in the
* OPL3 chip emulation. There was an explicit effort in making no optimizations,
* and making the code as legible as possible, so that a new programmer
* interested in modify and improve upon it could do so more easily.
* This emulator's main body of information was taken from reverse engineering of
* the OPL3 chip, from the YMF262 Datasheet and from the OPL3 section in the
* YMF278b Application's Manual,
* together with the vibrato table information, eighth waveform parameter
* information and feedback averaging information provided in MAME's YMF262 and
* YM3812 emulators, by Jarek Burczynski and Tatsuyuki Satoh.
* This emulator has a high degree of accuracy, and most of music files sound
* almost identical, exception made in some games which uses specific parts of
* the rhythm section. In this respect, some parts of the rhythm mode are still
* only an approximation of the real chip.
* The other thing to note is that this emulator was done through recordings of
* the SB16 DAC, so it has not bitwise precision. Additional equipment should be
* used to verify the samples directly from the chip, and allow this exact
* per-sample correspondence. As a good side-effect, since this emulator uses
* floating point and has a more fine-grained envelope generator, it can produce
* sometimes a crystal-clear, denser kind of OPL3 sound that, because of that,
* may be useful for creating new music.
*
* Version 1.0.6
*
*/
#include <math.h>
#include <stdlib.h>
#include <limits>
#include "opl.h"
#include "opl3_Float.h"
#define VOLUME_MUL 0.3333
static const double OPL_PI = 3.14159265358979323846; // matches value in gcc v2 math.h
namespace JavaOPL3
{
class Operator;
static inline double StripIntPart(double num)
{
#if 0
double dontcare;
return modf(num, &dontcare);
#else
return num - xs_RoundToInt(num);
#endif
}
//
// Channels
//
class Channel
{
protected:
double feedback[2];
int fnuml, fnumh, kon, block, fb, cha, chb, cnt;
// Factor to convert between normalized amplitude to normalized
// radians. The amplitude maximum is equivalent to 8*Pi radians.
#define toPhase (4.f)
public:
int channelBaseAddress;
double leftPan, rightPan;
Channel (int baseAddress, double startvol);
virtual ~Channel() {}
void update_2_KON1_BLOCK3_FNUMH2(class OPL3 *OPL3);
void update_FNUML8(class OPL3 *OPL3);
void update_CHD1_CHC1_CHB1_CHA1_FB3_CNT1(class OPL3 *OPL3);
void updateChannel(class OPL3 *OPL3);
void updatePan(class OPL3 *OPL3);
virtual double getChannelOutput(class OPL3 *OPL3) = 0;
virtual void keyOn() = 0;
virtual void keyOff() = 0;
virtual void updateOperators(class OPL3 *OPL3) = 0;
};
class Channel2op : public Channel
{
public:
Operator *op1, *op2;
Channel2op (int baseAddress, double startvol, Operator *o1, Operator *o2);
double getChannelOutput(class OPL3 *OPL3);
void keyOn();
void keyOff();
void updateOperators(class OPL3 *OPL3);
};
class Channel4op : public Channel
{
public:
Operator *op1, *op2, *op3, *op4;
Channel4op (int baseAddress, double startvol, Operator *o1, Operator *o2, Operator *o3, Operator *o4);
double getChannelOutput(class OPL3 *OPL3);
void keyOn();
void keyOff();
void updateOperators(class OPL3 *OPL3);
};
// There's just one instance of this class, that fills the eventual gaps in the Channel array;
class DisabledChannel : public Channel
{
public:
DisabledChannel() : Channel(0, 0) { }
double getChannelOutput(class OPL3 *OPL3) { return 0; }
void keyOn() { }
void keyOff() { }
void updateOperators(class OPL3 *OPL3) { }
};
//
// Envelope Generator
//
class EnvelopeGenerator
{
public:
enum Stage {ATTACK,DECAY,SUSTAIN,RELEASE,OFF};
Stage stage;
int actualAttackRate, actualDecayRate, actualReleaseRate;
double xAttackIncrement, xMinimumInAttack;
double dBdecayIncrement;
double dBreleaseIncrement;
double attenuation, totalLevel, sustainLevel;
double x, envelope;
public:
EnvelopeGenerator();
void setActualSustainLevel(int sl);
void setTotalLevel(int tl);
void setAtennuation(int f_number, int block, int ksl);
void setActualAttackRate(int attackRate, int ksr, int keyScaleNumber);
void setActualDecayRate(int decayRate, int ksr, int keyScaleNumber);
void setActualReleaseRate(int releaseRate, int ksr, int keyScaleNumber);
private:
int calculateActualRate(int rate, int ksr, int keyScaleNumber);
public:
double getEnvelope(OPL3 *OPL3, int egt, int am);
void keyOn();
void keyOff();
private:
static double dBtoX(double dB);
static double percentageToDB(double percentage);
static double percentageToX(double percentage);
};
//
// Phase Generator
//
class PhaseGenerator {
double phase, phaseIncrement;
public:
PhaseGenerator();
void setFrequency(int f_number, int block, int mult);
double getPhase(class OPL3 *OPL3, int vib);
void keyOn();
};
//
// Operators
//
class Operator
{
public:
PhaseGenerator phaseGenerator;
EnvelopeGenerator envelopeGenerator;
double envelope, phase;
int operatorBaseAddress;
int am, vib, ksr, egt, mult, ksl, tl, ar, dr, sl, rr, ws;
int keyScaleNumber, f_number, block;
static const double noModulator;
public:
Operator(int baseAddress);
void update_AM1_VIB1_EGT1_KSR1_MULT4(class OPL3 *OPL3);
void update_KSL2_TL6(class OPL3 *OPL3);
void update_AR4_DR4(class OPL3 *OPL3);
void update_SL4_RR4(class OPL3 *OPL3);
void update_5_WS3(class OPL3 *OPL3);
double getOperatorOutput(class OPL3 *OPL3, double modulator);
void keyOn();
void keyOff();
void updateOperator(class OPL3 *OPL3, int ksn, int f_num, int blk);
protected:
double getOutput(double modulator, double outputPhase, double *waveform);
};
//
// Rhythm
//
// The getOperatorOutput() method in TopCymbalOperator, HighHatOperator and SnareDrumOperator
// were made through purely empyrical reverse engineering of the OPL3 output.
class RhythmChannel : public Channel2op
{
public:
RhythmChannel(int baseAddress, double startvol, Operator *o1, Operator *o2)
: Channel2op(baseAddress, startvol, o1, o2)
{ }
double getChannelOutput(class OPL3 *OPL3);
// Rhythm channels are always running,
// only the envelope is activated by the user.
void keyOn() { }
void keyOff() { }
};
class HighHatSnareDrumChannel : public RhythmChannel {
static const int highHatSnareDrumChannelBaseAddress = 7;
public:
HighHatSnareDrumChannel(double startvol, Operator *o1, Operator *o2)
: RhythmChannel(highHatSnareDrumChannelBaseAddress, startvol, o1, o2)
{ }
};
class TomTomTopCymbalChannel : public RhythmChannel {
static const int tomTomTopCymbalChannelBaseAddress = 8;
public:
TomTomTopCymbalChannel(double startvol, Operator *o1, Operator *o2)
: RhythmChannel(tomTomTopCymbalChannelBaseAddress, startvol, o1, o2)
{ }
};
class TopCymbalOperator : public Operator {
static const int topCymbalOperatorBaseAddress = 0x15;
public:
TopCymbalOperator(int baseAddress);
TopCymbalOperator();
double getOperatorOutput(class OPL3 *OPL3, double modulator);
double getOperatorOutput(class OPL3 *OPL3, double modulator, double externalPhase);
};
class HighHatOperator : public TopCymbalOperator {
static const int highHatOperatorBaseAddress = 0x11;
public:
HighHatOperator();
double getOperatorOutput(class OPL3 *OPL3, double modulator);
};
class SnareDrumOperator : public Operator {
static const int snareDrumOperatorBaseAddress = 0x14;
public:
SnareDrumOperator();
double getOperatorOutput(class OPL3 *OPL3, double modulator);
};
class TomTomOperator : public Operator {
static const int tomTomOperatorBaseAddress = 0x12;
public:
TomTomOperator() : Operator(tomTomOperatorBaseAddress) { }
};
class BassDrumChannel : public Channel2op {
static const int bassDrumChannelBaseAddress = 6;
static const int op1BaseAddress = 0x10;
static const int op2BaseAddress = 0x13;
Operator my_op1, my_op2;
public:
BassDrumChannel(double startvol);
double getChannelOutput(class OPL3 *OPL3);
// Key ON and OFF are unused in rhythm channels.
void keyOn() { }
void keyOff() { }
};
//
// OPl3 Data
//
struct OPL3DataStruct
{
public:
// OPL3-wide registers offsets:
static const int
_1_NTS1_6_Offset = 0x08,
DAM1_DVB1_RYT1_BD1_SD1_TOM1_TC1_HH1_Offset = 0xBD,
_7_NEW1_Offset = 0x105,
_2_CONNECTIONSEL6_Offset = 0x104;
// The OPL3 tremolo repetition rate is 3.7 Hz.
#define tremoloFrequency (3.7)
static const int tremoloTableLength = (int)(OPL_SAMPLE_RATE/tremoloFrequency);
static const int vibratoTableLength = 8192;
OPL3DataStruct()
{
loadVibratoTable();
loadTremoloTable();
}
// The first array is used when DVB=0 and the second array is used when DVB=1.
double vibratoTable[2][vibratoTableLength];
// First array used when AM = 0 and second array used when AM = 1.
double tremoloTable[2][tremoloTableLength];
static double calculateIncrement(double begin, double end, double period) {
return (end-begin)/OPL_SAMPLE_RATE * (1/period);
}
private:
void loadVibratoTable();
void loadTremoloTable();
};
//
// Channel Data
//
struct ChannelData
{
static const int
_2_KON1_BLOCK3_FNUMH2_Offset = 0xB0,
FNUML8_Offset = 0xA0,
CHD1_CHC1_CHB1_CHA1_FB3_CNT1_Offset = 0xC0;
// Feedback rate in fractions of 2*Pi, normalized to (0,1):
// 0, Pi/16, Pi/8, Pi/4, Pi/2, Pi, 2*Pi, 4*Pi turns to be:
static const float feedback[8];
};
const float ChannelData::feedback[8] = {0,1/32.f,1/16.f,1/8.f,1/4.f,1/2.f,1,2};
//
// Operator Data
//
struct OperatorDataStruct
{
static const int
AM1_VIB1_EGT1_KSR1_MULT4_Offset = 0x20,
KSL2_TL6_Offset = 0x40,
AR4_DR4_Offset = 0x60,
SL4_RR4_Offset = 0x80,
_5_WS3_Offset = 0xE0;
enum type {NO_MODULATION, CARRIER, FEEDBACK};
static const int waveLength = 1024;
static const float multTable[16];
static const float ksl3dBtable[16][8];
//OPL3 has eight waveforms:
double waveforms[8][waveLength];
#define MIN_DB (-120.0)
#define DB_TABLE_RES (4.0)
#define DB_TABLE_SIZE (int)(-MIN_DB * DB_TABLE_RES)
double dbpow[DB_TABLE_SIZE];
#define ATTACK_MIN (-5.0)
#define ATTACK_MAX (8.0)
#define ATTACK_RES (0.03125)
#define ATTACK_TABLE_SIZE (int)((ATTACK_MAX - ATTACK_MIN) / ATTACK_RES)
double attackTable[ATTACK_TABLE_SIZE];
OperatorDataStruct()
{
loadWaveforms();
loaddBPowTable();
loadAttackTable();
}
static double log2(double x) {
return log(x)/log(2.0);
}
private:
void loadWaveforms();
void loaddBPowTable();
void loadAttackTable();
};
const float OperatorDataStruct::multTable[16] = {0.5,1,2,3,4,5,6,7,8,9,10,10,12,12,15,15};
const float OperatorDataStruct::ksl3dBtable[16][8] = {
{0,0,0,0,0,0,0,0},
{0,0,0,0,0,-3,-6,-9},
{0,0,0,0,-3,-6,-9,-12},
{0,0,0, -1.875, -4.875, -7.875, -10.875, -13.875},
{0,0,0,-3,-6,-9,-12,-15},
{0,0, -1.125, -4.125, -7.125, -10.125, -13.125, -16.125},
{0,0, -1.875, -4.875, -7.875, -10.875, -13.875, -16.875},
{0,0, -2.625, -5.625, -8.625, -11.625, -14.625, -17.625},
{0,0,-3,-6,-9,-12,-15,-18},
{0, -0.750, -3.750, -6.750, -9.750, -12.750, -15.750, -18.750},
{0, -1.125, -4.125, -7.125, -10.125, -13.125, -16.125, -19.125},
{0, -1.500, -4.500, -7.500, -10.500, -13.500, -16.500, -19.500},
{0, -1.875, -4.875, -7.875, -10.875, -13.875, -16.875, -19.875},
{0, -2.250, -5.250, -8.250, -11.250, -14.250, -17.250, -20.250},
{0, -2.625, -5.625, -8.625, -11.625, -14.625, -17.625, -20.625},
{0,-3,-6,-9,-12,-15,-18,-21}
};
//
// Envelope Generator Data
//
namespace EnvelopeGeneratorData
{
static const double MUGEN = std::numeric_limits<double>::infinity();
// This table is indexed by the value of Operator.ksr
// and the value of ChannelRegister.keyScaleNumber.
static const int rateOffset[2][16] = {
{0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3},
{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}
};
// These attack periods in miliseconds were taken from the YMF278B manual.
// The attack actual rates range from 0 to 63, with different data for
// 0%-100% and for 10%-90%:
static const double attackTimeValuesTable[64][2] = {
{MUGEN,MUGEN}, {MUGEN,MUGEN}, {MUGEN,MUGEN}, {MUGEN,MUGEN},
{2826.24,1482.75}, {2252.80,1155.07}, {1884.16,991.23}, {1597.44,868.35},
{1413.12,741.38}, {1126.40,577.54}, {942.08,495.62}, {798.72,434.18},
{706.56,370.69}, {563.20,288.77}, {471.04,247.81}, {399.36,217.09},
{353.28,185.34}, {281.60,144.38}, {235.52,123.90}, {199.68,108.54},
{176.76,92.67}, {140.80,72.19}, {117.76,61.95}, {99.84,54.27},
{88.32,46.34}, {70.40,36.10}, {58.88,30.98}, {49.92,27.14},
{44.16,23.17}, {35.20,18.05}, {29.44,15.49}, {24.96,13.57},
{22.08,11.58}, {17.60,9.02}, {14.72,7.74}, {12.48,6.78},
{11.04,5.79}, {8.80,4.51}, {7.36,3.87}, {6.24,3.39},
{5.52,2.90}, {4.40,2.26}, {3.68,1.94}, {3.12,1.70},
{2.76,1.45}, {2.20,1.13}, {1.84,0.97}, {1.56,0.85},
{1.40,0.73}, {1.12,0.61}, {0.92,0.49}, {0.80,0.43},
{0.70,0.37}, {0.56,0.31}, {0.46,0.26}, {0.42,0.22},
{0.38,0.19}, {0.30,0.14}, {0.24,0.11}, {0.20,0.11},
{0.00,0.00}, {0.00,0.00}, {0.00,0.00}, {0.00,0.00}
};
// These decay and release periods in milliseconds were taken from the YMF278B manual.
// The rate index range from 0 to 63, with different data for
// 0%-100% and for 10%-90%:
static const double decayAndReleaseTimeValuesTable[64][2] = {
{MUGEN,MUGEN}, {MUGEN,MUGEN}, {MUGEN,MUGEN}, {MUGEN,MUGEN},
{39280.64,8212.48}, {31416.32,6574.08}, {26173.44,5509.12}, {22446.08,4730.88},
{19640.32,4106.24}, {15708.16,3287.04}, {13086.72,2754.56}, {11223.04,2365.44},
{9820.16,2053.12}, {7854.08,1643.52}, {6543.36,1377.28}, {5611.52,1182.72},
{4910.08,1026.56}, {3927.04,821.76}, {3271.68,688.64}, {2805.76,591.36},
{2455.04,513.28}, {1936.52,410.88}, {1635.84,344.34}, {1402.88,295.68},
{1227.52,256.64}, {981.76,205.44}, {817.92,172.16}, {701.44,147.84},
{613.76,128.32}, {490.88,102.72}, {488.96,86.08}, {350.72,73.92},
{306.88,64.16}, {245.44,51.36}, {204.48,43.04}, {175.36,36.96},
{153.44,32.08}, {122.72,25.68}, {102.24,21.52}, {87.68,18.48},
{76.72,16.04}, {61.36,12.84}, {51.12,10.76}, {43.84,9.24},
{38.36,8.02}, {30.68,6.42}, {25.56,5.38}, {21.92,4.62},
{19.20,4.02}, {15.36,3.22}, {12.80,2.68}, {10.96,2.32},
{9.60,2.02}, {7.68,1.62}, {6.40,1.35}, {5.48,1.15},
{4.80,1.01}, {3.84,0.81}, {3.20,0.69}, {2.74,0.58},
{2.40,0.51}, {2.40,0.51}, {2.40,0.51}, {2.40,0.51}
};
};
class OPL3 : public OPLEmul
{
public:
uint8_t registers[0x200];
Operator *operators[2][0x20];
Channel2op *channels2op[2][9];
Channel4op *channels4op[2][3];
Channel *channels[2][9];
// Unique instance to fill future gaps in the Channel array,
// when there will be switches between 2op and 4op mode.
DisabledChannel disabledChannel;
// Specific operators to switch when in rhythm mode:
HighHatOperator highHatOperator;
SnareDrumOperator snareDrumOperator;
TomTomOperator tomTomOperator;
TomTomTopCymbalChannel tomTomTopCymbalChannel;
// Rhythm channels
BassDrumChannel bassDrumChannel;
HighHatSnareDrumChannel highHatSnareDrumChannel;
TopCymbalOperator topCymbalOperator;
Operator *highHatOperatorInNonRhythmMode;
Operator *snareDrumOperatorInNonRhythmMode;
Operator *tomTomOperatorInNonRhythmMode;
Operator *topCymbalOperatorInNonRhythmMode;
int nts, dam, dvb, ryt, bd, sd, tom, tc, hh, _new, connectionsel;
int vibratoIndex, tremoloIndex;
bool FullPan;
static OperatorDataStruct *OperatorData;
static OPL3DataStruct *OPL3Data;
// The methods read() and write() are the only
// ones needed by the user to interface with the emulator.
// read() returns one frame at a time, to be played at 49700 Hz,
// with each frame being four 16-bit samples,
// corresponding to the OPL3 four output channels CHA...CHD.
public:
//void read(float output[2]);
void write(int array, int address, int data);
OPL3(bool fullpan);
~OPL3();
private:
void initOperators();
void initChannels2op();
void initChannels4op();
void initRhythmChannels();
void initChannels();
void update_1_NTS1_6();
void update_DAM1_DVB1_RYT1_BD1_SD1_TOM1_TC1_HH1();
void update_7_NEW1();
void setEnabledChannels();
void updateChannelPans();
void update_2_CONNECTIONSEL6();
void set4opConnections();
void setRhythmMode();
static int InstanceCount;
// OPLEmul interface
public:
void Reset();
void WriteReg(int reg, int v);
void Update(float *buffer, int length);
void SetPanning(int c, float left, float right);
};
OperatorDataStruct *OPL3::OperatorData;
OPL3DataStruct *OPL3::OPL3Data;
int OPL3::InstanceCount;
void OPL3::Update(float *output, int numsamples) {
while (numsamples--) {
// If _new = 0, use OPL2 mode with 9 channels. If _new = 1, use OPL3 18 channels;
for(int array=0; array < (_new + 1); array++)
for(int channelNumber=0; channelNumber < 9; channelNumber++) {
// Reads output from each OPL3 channel, and accumulates it in the output buffer:
Channel *channel = channels[array][channelNumber];
if (channel != &disabledChannel)
{
double channelOutput = channel->getChannelOutput(this);
output[0] += float(channelOutput * channel->leftPan);
output[1] += float(channelOutput * channel->rightPan);
}
}
// Advances the OPL3-wide vibrato index, which is used by
// PhaseGenerator.getPhase() in each Operator.
vibratoIndex = (vibratoIndex + 1) & (OPL3DataStruct::vibratoTableLength - 1);
// Advances the OPL3-wide tremolo index, which is used by
// EnvelopeGenerator.getEnvelope() in each Operator.
tremoloIndex++;
if(tremoloIndex >= OPL3DataStruct::tremoloTableLength) tremoloIndex = 0;
output += 2;
}
}
void OPL3::write(int array, int address, int data) {
// The OPL3 has two registers arrays, each with adresses ranging
// from 0x00 to 0xF5.
// This emulator uses one array, with the two original register arrays
// starting at 0x00 and at 0x100.
int registerAddress = (array<<8) | address;
// If the address is out of the OPL3 memory map, returns.
if(registerAddress<0 || registerAddress>=0x200) return;
registers[registerAddress] = data;
switch(address&0xE0) {
// The first 3 bits masking gives the type of the register by using its base address:
// 0x00, 0x20, 0x40, 0x60, 0x80, 0xA0, 0xC0, 0xE0
// When it is needed, we further separate the register type inside each base address,
// which is the case of 0x00 and 0xA0.
// Through out this emulator we will use the same name convention to
// reference a byte with several bit registers.
// The name of each bit register will be followed by the number of bits
// it occupies inside the byte.
// Numbers without accompanying names are unused bits.
case 0x00:
// Unique registers for the entire OPL3:
if(array==1) {
if(address==0x04)
update_2_CONNECTIONSEL6();
else if(address==0x05)
update_7_NEW1();
}
else if(address==0x08) update_1_NTS1_6();
break;
case 0xA0:
// 0xBD is a control register for the entire OPL3:
if(address==0xBD) {
if(array==0)
update_DAM1_DVB1_RYT1_BD1_SD1_TOM1_TC1_HH1();
break;
}
// Registers for each channel are in A0-A8, B0-B8, C0-C8, in both register arrays.
// 0xB0...0xB8 keeps kon,block,fnum(h) for each channel.
if( (address&0xF0) == 0xB0 && address <= 0xB8) {
// If the address is in the second register array, adds 9 to the channel number.
// The channel number is given by the last four bits, like in A0,...,A8.
channels[array][address&0x0F]->update_2_KON1_BLOCK3_FNUMH2(this);
break;
}
// 0xA0...0xA8 keeps fnum(l) for each channel.
if( (address&0xF0) == 0xA0 && address <= 0xA8)
channels[array][address&0x0F]->update_FNUML8(this);
break;
// 0xC0...0xC8 keeps cha,chb,chc,chd,fb,cnt for each channel:
case 0xC0:
if(address <= 0xC8)
channels[array][address&0x0F]->update_CHD1_CHC1_CHB1_CHA1_FB3_CNT1(this);
break;
// Registers for each of the 36 Operators:
default:
int operatorOffset = address&0x1F;
if(operators[array][operatorOffset] == NULL) break;
switch(address&0xE0) {
// 0x20...0x35 keeps am,vib,egt,ksr,mult for each operator:
case 0x20:
operators[array][operatorOffset]->update_AM1_VIB1_EGT1_KSR1_MULT4(this);
break;
// 0x40...0x55 keeps ksl,tl for each operator:
case 0x40:
operators[array][operatorOffset]->update_KSL2_TL6(this);
break;
// 0x60...0x75 keeps ar,dr for each operator:
case 0x60:
operators[array][operatorOffset]->update_AR4_DR4(this);
break;
// 0x80...0x95 keeps sl,rr for each operator:
case 0x80:
operators[array][operatorOffset]->update_SL4_RR4(this);
break;
// 0xE0...0xF5 keeps ws for each operator:
case 0xE0:
operators[array][operatorOffset]->update_5_WS3(this);
}
}
}
OPL3::OPL3(bool fullpan)
: tomTomTopCymbalChannel(fullpan ? CENTER_PANNING_POWER : 1, &tomTomOperator, &topCymbalOperator),
bassDrumChannel(fullpan ? CENTER_PANNING_POWER : 1),
highHatSnareDrumChannel(fullpan ? CENTER_PANNING_POWER : 1, &highHatOperator, &snareDrumOperator)
{
FullPan = fullpan;
nts = dam = dvb = ryt = bd = sd = tom = tc = hh = _new = connectionsel = 0;
vibratoIndex = tremoloIndex = 0;
if (InstanceCount++ == 0)
{
OPL3Data = new struct OPL3DataStruct;
OperatorData = new struct OperatorDataStruct;
}
initOperators();
initChannels2op();
initChannels4op();
initRhythmChannels();
initChannels();
}
OPL3::~OPL3()
{
ryt = 0;
setRhythmMode(); // Make sure all operators point to the dynamically allocated ones.
for (int array = 0; array < 2; array++)
{
for (int operatorNumber = 0; operatorNumber < 0x20; operatorNumber++)
{
if (operators[array][operatorNumber] != NULL)
{
delete operators[array][operatorNumber];
}
}
for (int channelNumber = 0; channelNumber < 9; channelNumber++)
{
delete channels2op[array][channelNumber];
}
for (int channelNumber = 0; channelNumber < 3; channelNumber++)
{
delete channels4op[array][channelNumber];
}
}
if (--InstanceCount == 0)
{
delete OPL3Data;
OPL3Data = NULL;
delete OperatorData;
OperatorData = NULL;
}
}
void OPL3::initOperators() {
int baseAddress;
// The YMF262 has 36 operators:
memset(operators, 0, sizeof(operators));
for(int array=0; array<2; array++)
for(int group = 0; group<=0x10; group+=8)
for(int offset=0; offset<6; offset++) {
baseAddress = (array<<8) | (group+offset);
operators[array][group+offset] = new Operator(baseAddress);
}
// Save operators when they are in non-rhythm mode:
// Channel 7:
highHatOperatorInNonRhythmMode = operators[0][0x11];
snareDrumOperatorInNonRhythmMode = operators[0][0x14];
// Channel 8:
tomTomOperatorInNonRhythmMode = operators[0][0x12];
topCymbalOperatorInNonRhythmMode = operators[0][0x15];
}
void OPL3::initChannels2op() {
// The YMF262 has 18 2-op channels.
// Each 2-op channel can be at a serial or parallel operator configuration:
memset(channels2op, 0, sizeof(channels2op));
double startvol = FullPan ? CENTER_PANNING_POWER : 1;
for(int array=0; array<2; array++)
for(int channelNumber=0; channelNumber<3; channelNumber++) {
int baseAddress = (array<<8) | channelNumber;
// Channels 1, 2, 3 -> Operator offsets 0x0,0x3; 0x1,0x4; 0x2,0x5
channels2op[array][channelNumber] = new Channel2op(baseAddress, startvol, operators[array][channelNumber], operators[array][channelNumber+0x3]);
// Channels 4, 5, 6 -> Operator offsets 0x8,0xB; 0x9,0xC; 0xA,0xD
channels2op[array][channelNumber+3] = new Channel2op(baseAddress+3, startvol, operators[array][channelNumber+0x8], operators[array][channelNumber+0xB]);
// Channels 7, 8, 9 -> Operators 0x10,0x13; 0x11,0x14; 0x12,0x15
channels2op[array][channelNumber+6] = new Channel2op(baseAddress+6, startvol, operators[array][channelNumber+0x10], operators[array][channelNumber+0x13]);
}
}
void OPL3::initChannels4op() {
// The YMF262 has 3 4-op channels in each array:
memset(channels4op, 0, sizeof(channels4op));
double startvol = FullPan ? CENTER_PANNING_POWER : 1;
for(int array=0; array<2; array++)
for(int channelNumber=0; channelNumber<3; channelNumber++) {
int baseAddress = (array<<8) | channelNumber;
// Channels 1, 2, 3 -> Operators 0x0,0x3,0x8,0xB; 0x1,0x4,0x9,0xC; 0x2,0x5,0xA,0xD;
channels4op[array][channelNumber] = new Channel4op(baseAddress, startvol, operators[array][channelNumber], operators[array][channelNumber+0x3], operators[array][channelNumber+0x8], operators[array][channelNumber+0xB]);
}
}
void OPL3::initRhythmChannels() {
}
void OPL3::initChannels() {
// Channel is an abstract class that can be a 2-op, 4-op, rhythm or disabled channel,
// depending on the OPL3 configuration at the time.
// channels[] inits as a 2-op serial channel array:
for(int array=0; array<2; array++)
for(int i=0; i<9; i++) channels[array][i] = channels2op[array][i];
}
void OPL3::update_1_NTS1_6() {
int _1_nts1_6 = registers[OPL3DataStruct::_1_NTS1_6_Offset];
// Note Selection. This register is used in Channel.updateOperators() implementations,
// to calculate the channel´s Key Scale Number.
// The value of the actual envelope rate follows the value of
// OPL3.nts,Operator.keyScaleNumber and Operator.ksr
nts = (_1_nts1_6 & 0x40) >> 6;
}
void OPL3::update_DAM1_DVB1_RYT1_BD1_SD1_TOM1_TC1_HH1() {
int dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 = registers[OPL3DataStruct::DAM1_DVB1_RYT1_BD1_SD1_TOM1_TC1_HH1_Offset];
// Depth of amplitude. This register is used in EnvelopeGenerator.getEnvelope();
dam = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x80) >> 7;
// Depth of vibrato. This register is used in PhaseGenerator.getPhase();
dvb = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x40) >> 6;
int new_ryt = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x20) >> 5;
if(new_ryt != ryt) {
ryt = new_ryt;
setRhythmMode();
}
int new_bd = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x10) >> 4;
if(new_bd != bd) {
bd = new_bd;
if(bd==1) {
bassDrumChannel.op1->keyOn();
bassDrumChannel.op2->keyOn();
}
}
int new_sd = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x08) >> 3;
if(new_sd != sd) {
sd = new_sd;
if(sd==1) snareDrumOperator.keyOn();
}
int new_tom = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x04) >> 2;
if(new_tom != tom) {
tom = new_tom;
if(tom==1) tomTomOperator.keyOn();
}
int new_tc = (dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x02) >> 1;
if(new_tc != tc) {
tc = new_tc;
if(tc==1) topCymbalOperator.keyOn();
}
int new_hh = dam1_dvb1_ryt1_bd1_sd1_tom1_tc1_hh1 & 0x01;
if(new_hh != hh) {
hh = new_hh;
if(hh==1) highHatOperator.keyOn();
}
}
void OPL3::update_7_NEW1() {
int _7_new1 = registers[OPL3DataStruct::_7_NEW1_Offset];
// OPL2/OPL3 mode selection. This register is used in
// OPL3.read(), OPL3.write() and Operator.getOperatorOutput();
_new = (_7_new1 & 0x01);
if(_new==1) setEnabledChannels();
set4opConnections();
updateChannelPans();
}
void OPL3::setEnabledChannels() {
for(int array=0; array<2; array++)
for(int i=0; i<9; i++) {
int baseAddress = channels[array][i]->channelBaseAddress;
registers[baseAddress+ChannelData::CHD1_CHC1_CHB1_CHA1_FB3_CNT1_Offset] |= 0xF0;
channels[array][i]->update_CHD1_CHC1_CHB1_CHA1_FB3_CNT1(this);
}
}
void OPL3::updateChannelPans() {
for(int array=0; array<2; array++)
for(int i=0; i<9; i++) {
int baseAddress = channels[array][i]->channelBaseAddress;
registers[baseAddress+ChannelData::CHD1_CHC1_CHB1_CHA1_FB3_CNT1_Offset] |= 0xF0;
channels[array][i]->updatePan(this);
}
}
void OPL3::update_2_CONNECTIONSEL6() {
// This method is called only if _new is set.
int _2_connectionsel6 = registers[OPL3DataStruct::_2_CONNECTIONSEL6_Offset];
// 2-op/4-op channel selection. This register is used here to configure the OPL3.channels[] array.
connectionsel = (_2_connectionsel6 & 0x3F);
set4opConnections();
}
void OPL3::set4opConnections() {
// bits 0, 1, 2 sets respectively 2-op channels (1,4), (2,5), (3,6) to 4-op operation.
// bits 3, 4, 5 sets respectively 2-op channels (10,13), (11,14), (12,15) to 4-op operation.
for(int array=0; array<2; array++)
for(int i=0; i<3; i++) {
if(_new == 1) {
int shift = array*3 + i;
int connectionBit = (connectionsel >> shift) & 0x01;
if(connectionBit == 1) {
channels[array][i] = channels4op[array][i];
channels[array][i+3] = &disabledChannel;
channels[array][i]->updateChannel(this);
continue;
}
}
channels[array][i] = channels2op[array][i];
channels[array][i+3] = channels2op[array][i+3];
channels[array][i]->updateChannel(this);
channels[array][i+3]->updateChannel(this);
}
}
void OPL3::setRhythmMode() {
if(ryt==1) {
channels[0][6] = &bassDrumChannel;
channels[0][7] = &highHatSnareDrumChannel;
channels[0][8] = &tomTomTopCymbalChannel;
operators[0][0x11] = &highHatOperator;
operators[0][0x14] = &snareDrumOperator;
operators[0][0x12] = &tomTomOperator;
operators[0][0x15] = &topCymbalOperator;
}
else {
for(int i=6; i<=8; i++) channels[0][i] = channels2op[0][i];
operators[0][0x11] = highHatOperatorInNonRhythmMode;
operators[0][0x14] = snareDrumOperatorInNonRhythmMode;
operators[0][0x12] = tomTomOperatorInNonRhythmMode;
operators[0][0x15] = topCymbalOperatorInNonRhythmMode;
}
for(int i=6; i<=8; i++) channels[0][i]->updateChannel(this);
}
static double EnvelopeFromDB(double db)
{
#if 0
return pow(10.0, db/10);
#else
if (db < MIN_DB)
return 0;
return OPL3::OperatorData->dbpow[xs_FloorToInt(-db * DB_TABLE_RES)];
#endif
}
Channel::Channel (int baseAddress, double startvol) {
channelBaseAddress = baseAddress;
fnuml = fnumh = kon = block = fb = cnt = 0;
feedback[0] = feedback[1] = 0;
leftPan = rightPan = startvol;
}
void Channel::update_2_KON1_BLOCK3_FNUMH2(OPL3 *OPL3) {
int _2_kon1_block3_fnumh2 = OPL3->registers[channelBaseAddress+ChannelData::_2_KON1_BLOCK3_FNUMH2_Offset];
// Frequency Number (hi-register) and Block. These two registers, together with fnuml,
// sets the Channel´s base frequency;
block = (_2_kon1_block3_fnumh2 & 0x1C) >> 2;
fnumh = _2_kon1_block3_fnumh2 & 0x03;
updateOperators(OPL3);
// Key On. If changed, calls Channel.keyOn() / keyOff().
int newKon = (_2_kon1_block3_fnumh2 & 0x20) >> 5;
if(newKon != kon) {
if(newKon == 1) keyOn();
else keyOff();
kon = newKon;
}
}
void Channel::update_FNUML8(OPL3 *OPL3) {
int fnuml8 = OPL3->registers[channelBaseAddress+ChannelData::FNUML8_Offset];
// Frequency Number, low register.
fnuml = fnuml8&0xFF;
updateOperators(OPL3);
}
void Channel::update_CHD1_CHC1_CHB1_CHA1_FB3_CNT1(OPL3 *OPL3) {
int chd1_chc1_chb1_cha1_fb3_cnt1 = OPL3->registers[channelBaseAddress+ChannelData::CHD1_CHC1_CHB1_CHA1_FB3_CNT1_Offset];
// chd = (chd1_chc1_chb1_cha1_fb3_cnt1 & 0x80) >> 7;
// chc = (chd1_chc1_chb1_cha1_fb3_cnt1 & 0x40) >> 6;
chb = (chd1_chc1_chb1_cha1_fb3_cnt1 & 0x20) >> 5;
cha = (chd1_chc1_chb1_cha1_fb3_cnt1 & 0x10) >> 4;
fb = (chd1_chc1_chb1_cha1_fb3_cnt1 & 0x0E) >> 1;
cnt = chd1_chc1_chb1_cha1_fb3_cnt1 & 0x01;
updatePan(OPL3);
updateOperators(OPL3);
}
void Channel::updatePan(OPL3 *OPL3) {
if (!OPL3->FullPan)
{
if (OPL3->_new == 0)
{
leftPan = VOLUME_MUL;
rightPan = VOLUME_MUL;
}
else
{
leftPan = cha * VOLUME_MUL;
rightPan = chb * VOLUME_MUL;
}
}
}
void Channel::updateChannel(OPL3 *OPL3) {
update_2_KON1_BLOCK3_FNUMH2(OPL3);
update_FNUML8(OPL3);
update_CHD1_CHC1_CHB1_CHA1_FB3_CNT1(OPL3);
}
Channel2op::Channel2op (int baseAddress, double startvol, Operator *o1, Operator *o2)
: Channel(baseAddress, startvol)
{
op1 = o1;
op2 = o2;
}
double Channel2op::getChannelOutput(OPL3 *OPL3) {
double channelOutput = 0, op1Output = 0, op2Output = 0;
// The feedback uses the last two outputs from
// the first operator, instead of just the last one.
double feedbackOutput = (feedback[0] + feedback[1]) / 2;
switch(cnt) {
// CNT = 0, the operators are in series, with the first in feedback.
case 0:
if(op2->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
channelOutput = op2->getOperatorOutput(OPL3, op1Output*toPhase);
break;
// CNT = 1, the operators are in parallel, with the first in feedback.
case 1:
if(op1->envelopeGenerator.stage==EnvelopeGenerator::OFF &&
op2->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
op2Output = op2->getOperatorOutput(OPL3, Operator::noModulator);
channelOutput = (op1Output + op2Output) / 2;
}
feedback[0] = feedback[1];
feedback[1] = StripIntPart(op1Output * ChannelData::feedback[fb]);
return channelOutput;
}
void Channel2op::keyOn() {
op1->keyOn();
op2->keyOn();
feedback[0] = feedback[1] = 0;
}
void Channel2op::keyOff() {
op1->keyOff();
op2->keyOff();
}
void Channel2op::updateOperators(OPL3 *OPL3) {
// Key Scale Number, used in EnvelopeGenerator.setActualRates().
int keyScaleNumber = block*2 + ((fnumh>>OPL3->nts)&0x01);
int f_number = (fnumh<<8) | fnuml;
op1->updateOperator(OPL3, keyScaleNumber, f_number, block);
op2->updateOperator(OPL3, keyScaleNumber, f_number, block);
}
Channel4op::Channel4op (int baseAddress, double startvol, Operator *o1, Operator *o2, Operator *o3, Operator *o4)
: Channel(baseAddress, startvol)
{
op1 = o1;
op2 = o2;
op3 = o3;
op4 = o4;
}
double Channel4op::getChannelOutput(OPL3 *OPL3) {
double channelOutput = 0,
op1Output = 0, op2Output = 0, op3Output = 0, op4Output = 0;
int secondChannelBaseAddress = channelBaseAddress+3;
int secondCnt = OPL3->registers[secondChannelBaseAddress+ChannelData::CHD1_CHC1_CHB1_CHA1_FB3_CNT1_Offset] & 0x1;
int cnt4op = (cnt << 1) | secondCnt;
double feedbackOutput = (feedback[0] + feedback[1]) / 2;
switch(cnt4op) {
case 0:
if(op4->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
op2Output = op2->getOperatorOutput(OPL3, op1Output*toPhase);
op3Output = op3->getOperatorOutput(OPL3, op2Output*toPhase);
channelOutput = op4->getOperatorOutput(OPL3, op3Output*toPhase);
break;
case 1:
if(op2->envelopeGenerator.stage==EnvelopeGenerator::OFF &&
op4->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
op2Output = op2->getOperatorOutput(OPL3, op1Output*toPhase);
op3Output = op3->getOperatorOutput(OPL3, Operator::noModulator);
op4Output = op4->getOperatorOutput(OPL3, op3Output*toPhase);
channelOutput = (op2Output + op4Output) / 2;
break;
case 2:
if(op1->envelopeGenerator.stage==EnvelopeGenerator::OFF &&
op4->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
op2Output = op2->getOperatorOutput(OPL3, Operator::noModulator);
op3Output = op3->getOperatorOutput(OPL3, op2Output*toPhase);
op4Output = op4->getOperatorOutput(OPL3, op3Output*toPhase);
channelOutput = (op1Output + op4Output) / 2;
break;
case 3:
if(op1->envelopeGenerator.stage==EnvelopeGenerator::OFF &&
op3->envelopeGenerator.stage==EnvelopeGenerator::OFF &&
op4->envelopeGenerator.stage==EnvelopeGenerator::OFF)
return 0;
op1Output = op1->getOperatorOutput(OPL3, feedbackOutput);
op2Output = op2->getOperatorOutput(OPL3, Operator::noModulator);
op3Output = op3->getOperatorOutput(OPL3, op2Output*toPhase);
op4Output = op4->getOperatorOutput(OPL3, Operator::noModulator);
channelOutput = (op1Output + op3Output + op4Output) / 3;
}
feedback[0] = feedback[1];
feedback[1] = StripIntPart(op1Output * ChannelData::feedback[fb]);
return channelOutput;
}
void Channel4op::keyOn() {
op1->keyOn();
op2->keyOn();
op3->keyOn();
op4->keyOn();
feedback[0] = feedback[1] = 0;
}
void Channel4op::keyOff() {
op1->keyOff();
op2->keyOff();
op3->keyOff();
op4->keyOff();
}
void Channel4op::updateOperators(OPL3 *OPL3) {
// Key Scale Number, used in EnvelopeGenerator.setActualRates().
int keyScaleNumber = block*2 + ((fnumh>>OPL3->nts)&0x01);
int f_number = (fnumh<<8) | fnuml;
op1->updateOperator(OPL3, keyScaleNumber, f_number, block);
op2->updateOperator(OPL3, keyScaleNumber, f_number, block);
op3->updateOperator(OPL3, keyScaleNumber, f_number, block);
op4->updateOperator(OPL3, keyScaleNumber, f_number, block);
}
const double Operator::noModulator = 0;
Operator::Operator(int baseAddress) {
operatorBaseAddress = baseAddress;
envelope = 0;
am = vib = ksr = egt = mult = ksl = tl = ar = dr = sl = rr = ws = 0;
keyScaleNumber = f_number = block = 0;
}
void Operator::update_AM1_VIB1_EGT1_KSR1_MULT4(OPL3 *OPL3) {
int am1_vib1_egt1_ksr1_mult4 = OPL3->registers[operatorBaseAddress+OperatorDataStruct::AM1_VIB1_EGT1_KSR1_MULT4_Offset];
// Amplitude Modulation. This register is used int EnvelopeGenerator.getEnvelope();
am = (am1_vib1_egt1_ksr1_mult4 & 0x80) >> 7;
// Vibrato. This register is used in PhaseGenerator.getPhase();
vib = (am1_vib1_egt1_ksr1_mult4 & 0x40) >> 6;
// Envelope Generator Type. This register is used in EnvelopeGenerator.getEnvelope();
egt = (am1_vib1_egt1_ksr1_mult4 & 0x20) >> 5;
// Key Scale Rate. Sets the actual envelope rate together with rate and keyScaleNumber.
// This register os used in EnvelopeGenerator.setActualAttackRate().
ksr = (am1_vib1_egt1_ksr1_mult4 & 0x10) >> 4;
// Multiple. Multiplies the Channel.baseFrequency to get the Operator.operatorFrequency.
// This register is used in PhaseGenerator.setFrequency().
mult = am1_vib1_egt1_ksr1_mult4 & 0x0F;
phaseGenerator.setFrequency(f_number, block, mult);
envelopeGenerator.setActualAttackRate(ar, ksr, keyScaleNumber);
envelopeGenerator.setActualDecayRate(dr, ksr, keyScaleNumber);
envelopeGenerator.setActualReleaseRate(rr, ksr, keyScaleNumber);
}
void Operator::update_KSL2_TL6(OPL3 *OPL3) {
int ksl2_tl6 = OPL3->registers[operatorBaseAddress+OperatorDataStruct::KSL2_TL6_Offset];
// Key Scale Level. Sets the attenuation in accordance with the octave.
ksl = (ksl2_tl6 & 0xC0) >> 6;
// Total Level. Sets the overall damping for the envelope.
tl = ksl2_tl6 & 0x3F;
envelopeGenerator.setAtennuation(f_number, block, ksl);
envelopeGenerator.setTotalLevel(tl);
}
void Operator::update_AR4_DR4(OPL3 *OPL3) {
int ar4_dr4 = OPL3->registers[operatorBaseAddress+OperatorDataStruct::AR4_DR4_Offset];
// Attack Rate.
ar = (ar4_dr4 & 0xF0) >> 4;
// Decay Rate.
dr = ar4_dr4 & 0x0F;
envelopeGenerator.setActualAttackRate(ar, ksr, keyScaleNumber);
envelopeGenerator.setActualDecayRate(dr, ksr, keyScaleNumber);
}
void Operator::update_SL4_RR4(OPL3 *OPL3) {
int sl4_rr4 = OPL3->registers[operatorBaseAddress+OperatorDataStruct::SL4_RR4_Offset];
// Sustain Level.
sl = (sl4_rr4 & 0xF0) >> 4;
// Release Rate.
rr = sl4_rr4 & 0x0F;
envelopeGenerator.setActualSustainLevel(sl);
envelopeGenerator.setActualReleaseRate(rr, ksr, keyScaleNumber);
}
void Operator::update_5_WS3(OPL3 *OPL3) {
int _5_ws3 = OPL3->registers[operatorBaseAddress+OperatorDataStruct::_5_WS3_Offset];
ws = _5_ws3 & 0x07;
}
double Operator::getOperatorOutput(OPL3 *OPL3, double modulator) {
if(envelopeGenerator.stage == EnvelopeGenerator::OFF) return 0;
double envelopeInDB = envelopeGenerator.getEnvelope(OPL3, egt, am);
envelope = EnvelopeFromDB(envelopeInDB);
// If it is in OPL2 mode, use first four waveforms only:
ws &= ((OPL3->_new<<2) + 3);
double *waveform = OPL3::OperatorData->waveforms[ws];
phase = phaseGenerator.getPhase(OPL3, vib);
double operatorOutput = getOutput(modulator, phase, waveform);
return operatorOutput;
}
double Operator::getOutput(double modulator, double outputPhase, double *waveform) {
int sampleIndex = xs_FloorToInt((outputPhase + modulator) * OperatorDataStruct::waveLength) & (OperatorDataStruct::waveLength - 1);
return waveform[sampleIndex] * envelope;
}
void Operator::keyOn() {
if(ar > 0) {
envelopeGenerator.keyOn();
phaseGenerator.keyOn();
}
else envelopeGenerator.stage = EnvelopeGenerator::OFF;
}
void Operator::keyOff() {
envelopeGenerator.keyOff();
}
void Operator::updateOperator(OPL3 *OPL3, int ksn, int f_num, int blk) {
keyScaleNumber = ksn;
f_number = f_num;
block = blk;
update_AM1_VIB1_EGT1_KSR1_MULT4(OPL3);
update_KSL2_TL6(OPL3);
update_AR4_DR4(OPL3);
update_SL4_RR4(OPL3);
update_5_WS3(OPL3);
}
EnvelopeGenerator::EnvelopeGenerator() {
stage = OFF;
actualAttackRate = actualDecayRate = actualReleaseRate = 0;
xAttackIncrement = xMinimumInAttack = 0;
dBdecayIncrement = 0;
dBreleaseIncrement = 0;
attenuation = totalLevel = sustainLevel = 0;
x = dBtoX(-96);
envelope = -96;
}
void EnvelopeGenerator::setActualSustainLevel(int sl) {
// If all SL bits are 1, sustain level is set to -93 dB:
if(sl == 0x0F) {
sustainLevel = -93;
return;
}
// The datasheet states that the SL formula is
// sustainLevel = -24*d7 -12*d6 -6*d5 -3*d4,
// translated as:
sustainLevel = -3*sl;
}
void EnvelopeGenerator::setTotalLevel(int tl) {
// The datasheet states that the TL formula is
// TL = -(24*d5 + 12*d4 + 6*d3 + 3*d2 + 1.5*d1 + 0.75*d0),
// translated as:
totalLevel = tl*-0.75;
}
void EnvelopeGenerator::setAtennuation(int f_number, int block, int ksl) {
int hi4bits = (f_number>>6)&0x0F;
switch(ksl) {
case 0:
attenuation = 0;
break;
case 1:
// ~3 dB/Octave
attenuation = OperatorDataStruct::ksl3dBtable[hi4bits][block];
break;
case 2:
// ~1.5 dB/Octave
attenuation = OperatorDataStruct::ksl3dBtable[hi4bits][block]/2;
break;
case 3:
// ~6 dB/Octave
attenuation = OperatorDataStruct::ksl3dBtable[hi4bits][block]*2;
}
}
void EnvelopeGenerator::setActualAttackRate(int attackRate, int ksr, int keyScaleNumber) {
// According to the YMF278B manual's OPL3 section, the attack curve is exponential,
// with a dynamic range from -96 dB to 0 dB and a resolution of 0.1875 dB
// per level.
//
// This method sets an attack increment and attack minimum value
// that creates a exponential dB curve with 'period0to100' seconds in length
// and 'period10to90' seconds between 10% and 90% of the curve total level.
actualAttackRate = calculateActualRate(attackRate, ksr, keyScaleNumber);
double period0to100inSeconds = EnvelopeGeneratorData::attackTimeValuesTable[actualAttackRate][0]/1000.0;
int period0to100inSamples = (int)(period0to100inSeconds*OPL_SAMPLE_RATE);
double period10to90inSeconds = EnvelopeGeneratorData::attackTimeValuesTable[actualAttackRate][1]/1000.0;
int period10to90inSamples = (int)(period10to90inSeconds*OPL_SAMPLE_RATE);
// The x increment is dictated by the period between 10% and 90%:
xAttackIncrement = OPL3DataStruct::calculateIncrement(percentageToX(0.1), percentageToX(0.9), period10to90inSeconds);
// Discover how many samples are still from the top.
// It cannot reach 0 dB, since x is a logarithmic parameter and would be
// negative infinity. So we will use -0.1875 dB as the resolution
// maximum.
//
// percentageToX(0.9) + samplesToTheTop*xAttackIncrement = dBToX(-0.1875); ->
// samplesToTheTop = (dBtoX(-0.1875) - percentageToX(0.9)) / xAttackIncrement); ->
// period10to100InSamples = period10to90InSamples + samplesToTheTop; ->
int period10to100inSamples = (int) (period10to90inSamples + (dBtoX(-0.1875) - percentageToX(0.9)) / xAttackIncrement);
// Discover the minimum x that, through the attackIncrement value, keeps
// the 10%-90% period, and reaches 0 dB at the total period:
xMinimumInAttack = percentageToX(0.1) - (period0to100inSamples-period10to100inSamples)*xAttackIncrement;
}
void EnvelopeGenerator::setActualDecayRate(int decayRate, int ksr, int keyScaleNumber) {
actualDecayRate = calculateActualRate(decayRate, ksr, keyScaleNumber);
double period10to90inSeconds = EnvelopeGeneratorData::decayAndReleaseTimeValuesTable[actualDecayRate][1]/1000.0;
// Differently from the attack curve, the decay/release curve is linear.
// The dB increment is dictated by the period between 10% and 90%:
dBdecayIncrement = OPL3DataStruct::calculateIncrement(percentageToDB(0.1), percentageToDB(0.9), period10to90inSeconds);
}
void EnvelopeGenerator::setActualReleaseRate(int releaseRate, int ksr, int keyScaleNumber) {
actualReleaseRate = calculateActualRate(releaseRate, ksr, keyScaleNumber);
double period10to90inSeconds = EnvelopeGeneratorData::decayAndReleaseTimeValuesTable[actualReleaseRate][1]/1000.0;
dBreleaseIncrement = OPL3DataStruct::calculateIncrement(percentageToDB(0.1), percentageToDB(0.9), period10to90inSeconds);
}
int EnvelopeGenerator::calculateActualRate(int rate, int ksr, int keyScaleNumber) {
int rof = EnvelopeGeneratorData::rateOffset[ksr][keyScaleNumber];
int actualRate = rate*4 + rof;
// If, as an example at the maximum, rate is 15 and the rate offset is 15,
// the value would
// be 75, but the maximum allowed is 63:
if(actualRate > 63) actualRate = 63;
return actualRate;
}
double EnvelopeGenerator::getEnvelope(OPL3 *OPL3, int egt, int am) {
// The datasheets attenuation values
// must be halved to match the real OPL3 output.
double envelopeSustainLevel = sustainLevel / 2;
double envelopeTremolo =
OPL3::OPL3Data->tremoloTable[OPL3->dam][OPL3->tremoloIndex] / 2;
double envelopeAttenuation = attenuation / 2;
double envelopeTotalLevel = totalLevel / 2;
double envelopeMinimum = -96;
double envelopeResolution = 0.1875;
double outputEnvelope;
//
// Envelope Generation
//
switch(stage) {
case ATTACK:
// Since the attack is exponential, it will never reach 0 dB, so
// we´ll work with the next to maximum in the envelope resolution.
if(envelope<-envelopeResolution && xAttackIncrement != -EnvelopeGeneratorData::MUGEN) {
// The attack is exponential.
#if 0
envelope = -pow(2.0,x);
#else
int index = xs_FloorToInt((x - ATTACK_MIN) / ATTACK_RES);
if (index < 0)
envelope = OPL3::OperatorData->attackTable[0];
else if (index >= ATTACK_TABLE_SIZE)
envelope = OPL3::OperatorData->attackTable[ATTACK_TABLE_SIZE-1];
else
envelope = OPL3::OperatorData->attackTable[index];
#endif
x += xAttackIncrement;
break;
}
else {
// It is needed here to explicitly set envelope = 0, since
// only the attack can have a period of
// 0 seconds and produce an infinity envelope increment.
envelope = 0;
stage = DECAY;
}
case DECAY:
// The decay and release are linear.
if(envelope>envelopeSustainLevel) {
envelope -= dBdecayIncrement;
break;
}
else
stage = SUSTAIN;
case SUSTAIN:
// The Sustain stage is mantained all the time of the Key ON,
// even if we are in non-sustaining mode.
// This is necessary because, if the key is still pressed, we can
// change back and forth the state of EGT, and it will release and
// hold again accordingly.
if(egt==1) break;
else {
if(envelope > envelopeMinimum)
envelope -= dBreleaseIncrement;
else stage = OFF;
}
break;
case RELEASE:
// If we have Key OFF, only here we are in the Release stage.
// Now, we can turn EGT back and forth and it will have no effect,i.e.,
// it will release inexorably to the Off stage.
if(envelope > envelopeMinimum)
envelope -= dBreleaseIncrement;
else stage = OFF;
case OFF:
break;
}
// Ongoing original envelope
outputEnvelope = envelope;
//Tremolo
if(am == 1) outputEnvelope += envelopeTremolo;
//Attenuation
outputEnvelope += envelopeAttenuation;
//Total Level
outputEnvelope += envelopeTotalLevel;
return outputEnvelope;
}
void EnvelopeGenerator::keyOn() {
// If we are taking it in the middle of a previous envelope,
// start to rise from the current level:
// envelope = - (2 ^ x); ->
// 2 ^ x = -envelope ->
// x = log2(-envelope); ->
double xCurrent = OperatorDataStruct::log2(-envelope);
x = xCurrent < xMinimumInAttack ? xCurrent : xMinimumInAttack;
stage = ATTACK;
}
void EnvelopeGenerator::keyOff() {
if(stage != OFF) stage = RELEASE;
}
double EnvelopeGenerator::dBtoX(double dB) {
return OperatorDataStruct::log2(-dB);
}
double EnvelopeGenerator::percentageToDB(double percentage) {
return log10(percentage) * 10.0;
}
double EnvelopeGenerator::percentageToX(double percentage) {
return dBtoX(percentageToDB(percentage));
}
PhaseGenerator::PhaseGenerator() {
phase = phaseIncrement = 0;
}
void PhaseGenerator::setFrequency(int f_number, int block, int mult) {
// This frequency formula is derived from the following equation:
// f_number = baseFrequency * pow(2,19) / OPL_SAMPLE_RATE / pow(2,block-1);
double baseFrequency =
f_number * pow(2.0, block-1) * OPL_SAMPLE_RATE / pow(2.0,19);
double operatorFrequency = baseFrequency*OperatorDataStruct::multTable[mult];
// phase goes from 0 to 1 at
// period = (1/frequency) seconds ->
// Samples in each period is (1/frequency)*OPL_SAMPLE_RATE =
// = OPL_SAMPLE_RATE/frequency ->
// So the increment in each sample, to go from 0 to 1, is:
// increment = (1-0) / samples in the period ->
// increment = 1 / (OPL_SAMPLE_RATE/operatorFrequency) ->
phaseIncrement = operatorFrequency/OPL_SAMPLE_RATE;
}
double PhaseGenerator::getPhase(OPL3 *OPL3, int vib) {
if(vib==1)
// phaseIncrement = (operatorFrequency * vibrato) / OPL_SAMPLE_RATE
phase += phaseIncrement*OPL3::OPL3Data->vibratoTable[OPL3->dvb][OPL3->vibratoIndex];
else
// phaseIncrement = operatorFrequency / OPL_SAMPLE_RATE
phase += phaseIncrement;
// Originally clamped phase to [0,1), but that's not needed
return phase;
}
void PhaseGenerator::keyOn() {
phase = 0;
}
double RhythmChannel::getChannelOutput(OPL3 *OPL3) {
double channelOutput = 0, op1Output = 0, op2Output = 0;
// Note that, different from the common channel,
// we do not check to see if the Operator's envelopes are Off.
// Instead, we always do the calculations,
// to update the publicly available phase.
op1Output = op1->getOperatorOutput(OPL3, Operator::noModulator);
op2Output = op2->getOperatorOutput(OPL3, Operator::noModulator);
channelOutput = (op1Output + op2Output) / 2;
return channelOutput;
};
TopCymbalOperator::TopCymbalOperator(int baseAddress)
: Operator(baseAddress)
{ }
TopCymbalOperator::TopCymbalOperator()
: Operator(topCymbalOperatorBaseAddress)
{ }
double TopCymbalOperator::getOperatorOutput(OPL3 *OPL3, double modulator) {
double highHatOperatorPhase =
OPL3->highHatOperator.phase * OperatorDataStruct::multTable[OPL3->highHatOperator.mult];
// The Top Cymbal operator uses its own phase together with the High Hat phase.
return getOperatorOutput(OPL3, modulator, highHatOperatorPhase);
}
// This method is used here with the HighHatOperator phase
// as the externalPhase.
// Conversely, this method is also used through inheritance by the HighHatOperator,
// now with the TopCymbalOperator phase as the externalPhase.
double TopCymbalOperator::getOperatorOutput(OPL3 *OPL3, double modulator, double externalPhase) {
double envelopeInDB = envelopeGenerator.getEnvelope(OPL3, egt, am);
envelope = EnvelopeFromDB(envelopeInDB);
phase = phaseGenerator.getPhase(OPL3, vib);
int waveIndex = ws & ((OPL3->_new<<2) + 3);
double *waveform = OPL3::OperatorData->waveforms[waveIndex];
// Empirically tested multiplied phase for the Top Cymbal:
double carrierPhase = 8 * phase;
double modulatorPhase = externalPhase;
double modulatorOutput = getOutput(Operator::noModulator, modulatorPhase, waveform);
double carrierOutput = getOutput(modulatorOutput, carrierPhase, waveform);
int cycles = 4;
double chopped = (carrierPhase * cycles) /* %cycles */;
chopped = chopped - floor(chopped / cycles) * cycles;
if( chopped > 0.1) carrierOutput = 0;
return carrierOutput*2;
}
HighHatOperator::HighHatOperator()
: TopCymbalOperator(highHatOperatorBaseAddress)
{ }
double HighHatOperator::getOperatorOutput(OPL3 *OPL3, double modulator) {
double topCymbalOperatorPhase =
OPL3->topCymbalOperator.phase * OperatorDataStruct::multTable[OPL3->topCymbalOperator.mult];
// The sound output from the High Hat resembles the one from
// Top Cymbal, so we use the parent method and modify its output
// accordingly afterwards.
double operatorOutput = TopCymbalOperator::getOperatorOutput(OPL3, modulator, topCymbalOperatorPhase);
double randval = rand() / (double)RAND_MAX;
if(operatorOutput == 0) operatorOutput = randval*envelope;
return operatorOutput;
}
SnareDrumOperator::SnareDrumOperator()
: Operator(snareDrumOperatorBaseAddress)
{ }
double SnareDrumOperator::getOperatorOutput(OPL3 *OPL3, double modulator) {
if(envelopeGenerator.stage == EnvelopeGenerator::OFF) return 0;
double envelopeInDB = envelopeGenerator.getEnvelope(OPL3, egt, am);
envelope = EnvelopeFromDB(envelopeInDB);
// If it is in OPL2 mode, use first four waveforms only:
int waveIndex = ws & ((OPL3->_new<<2) + 3);
double *waveform = OPL3::OperatorData->waveforms[waveIndex];
phase = OPL3->highHatOperator.phase * 2;
double operatorOutput = getOutput(modulator, phase, waveform);
double randval = rand() / (double)RAND_MAX;
double noise = randval * envelope;
if(operatorOutput/envelope != 1 && operatorOutput/envelope != -1) {
if(operatorOutput > 0) operatorOutput = noise;
else if(operatorOutput < 0) operatorOutput = -noise;
else operatorOutput = 0;
}
return operatorOutput*2;
}
BassDrumChannel::BassDrumChannel(double startvol)
: Channel2op(bassDrumChannelBaseAddress, startvol, &my_op1, &my_op2),
my_op1(op1BaseAddress), my_op2(op2BaseAddress)
{ }
double BassDrumChannel::getChannelOutput(OPL3 *OPL3) {
// Bass Drum ignores first operator, when it is in series.
if(cnt == 1) op1->ar=0;
return Channel2op::getChannelOutput(OPL3);
}
void OPL3DataStruct::loadVibratoTable() {
// According to the YMF262 datasheet, the OPL3 vibrato repetition rate is 6.1 Hz.
// According to the YMF278B manual, it is 6.0 Hz.
// The information that the vibrato table has 8 levels standing 1024 samples each
// was taken from the emulator by Jarek Burczynski and Tatsuyuki Satoh,
// with a frequency of 6,06689453125 Hz, what makes sense with the difference
// in the information on the datasheets.
const double semitone = pow(2.0,1/12.0);
// A cent is 1/100 of a semitone:
const double cent = pow(semitone, 1/100.0);
// When dvb=0, the depth is 7 cents, when it is 1, the depth is 14 cents.
const double DVB0 = pow(cent,7.0);
const double DVB1 = pow(cent,14.0);
int i;
for(i = 0; i<1024; i++)
vibratoTable[0][i] = vibratoTable[1][i] = 1;
for(;i<2048; i++) {
vibratoTable[0][i] = sqrt(DVB0);
vibratoTable[1][i] = sqrt(DVB1);
}
for(;i<3072; i++) {
vibratoTable[0][i] = DVB0;
vibratoTable[1][i] = DVB1;
}
for(;i<4096; i++) {
vibratoTable[0][i] = sqrt(DVB0);
vibratoTable[1][i] = sqrt(DVB1);
}
for(; i<5120; i++)
vibratoTable[0][i] = vibratoTable[1][i] = 1;
for(;i<6144; i++) {
vibratoTable[0][i] = 1/sqrt(DVB0);
vibratoTable[1][i] = 1/sqrt(DVB1);
}
for(;i<7168; i++) {
vibratoTable[0][i] = 1/DVB0;
vibratoTable[1][i] = 1/DVB1;
}
for(;i<8192; i++) {
vibratoTable[0][i] = 1/sqrt(DVB0);
vibratoTable[1][i] = 1/sqrt(DVB1);
}
}
void OPL3DataStruct::loadTremoloTable()
{
// The tremolo depth is -1 dB when DAM = 0, and -4.8 dB when DAM = 1.
static const double tremoloDepth[] = {-1, -4.8};
// According to the YMF278B manual's OPL3 section graph,
// the tremolo waveform is not
// \ / a sine wave, but a single triangle waveform.
// \ / Thus, the period to achieve the tremolo depth is T/2, and
// \ / the increment in each T/2 section uses a frequency of 2*f.
// \/ Tremolo varies from 0 dB to depth, to 0 dB again, at frequency*2:
const double tremoloIncrement[] = {
calculateIncrement(tremoloDepth[0],0,1/(2*tremoloFrequency)),
calculateIncrement(tremoloDepth[1],0,1/(2*tremoloFrequency))
};
int tremoloTableLength = (int)(OPL_SAMPLE_RATE/tremoloFrequency);
// This is undocumented. The tremolo starts at the maximum attenuation,
// instead of at 0 dB:
tremoloTable[0][0] = tremoloDepth[0];
tremoloTable[1][0] = tremoloDepth[1];
int counter = 0;
// The first half of the triangle waveform:
while(tremoloTable[0][counter]<0) {
counter++;
tremoloTable[0][counter] = tremoloTable[0][counter-1] + tremoloIncrement[0];
tremoloTable[1][counter] = tremoloTable[1][counter-1] + tremoloIncrement[1];
}
// The second half of the triangle waveform:
while(tremoloTable[0][counter]>tremoloDepth[0] && counter<tremoloTableLength-1) {
counter++;
tremoloTable[0][counter] = tremoloTable[0][counter-1] - tremoloIncrement[0];
tremoloTable[1][counter] = tremoloTable[1][counter-1] - tremoloIncrement[1];
}
}
void OperatorDataStruct::loadWaveforms() {
int i;
// 1st waveform: sinusoid.
double theta = 0, thetaIncrement = 2*OPL_PI / 1024;
for(i=0, theta=0; i<1024; i++, theta += thetaIncrement)
waveforms[0][i] = sin(theta);
double *sineTable = waveforms[0];
// 2nd: first half of a sinusoid.
for(i=0; i<512; i++) {
waveforms[1][i] = sineTable[i];
waveforms[1][512+i] = 0;
}
// 3rd: double positive sinusoid.
for(i=0; i<512; i++)
waveforms[2][i] = waveforms[2][512+i] = sineTable[i];
// 4th: first and third quarter of double positive sinusoid.
for(i=0; i<256; i++) {
waveforms[3][i] = waveforms[3][512+i] = sineTable[i];
waveforms[3][256+i] = waveforms[3][768+i] = 0;
}
// 5th: first half with double frequency sinusoid.
for(i=0; i<512; i++) {
waveforms[4][i] = sineTable[i*2];
waveforms[4][512+i] = 0;
}
// 6th: first half with double frequency positive sinusoid.
for(i=0; i<256; i++) {
waveforms[5][i] = waveforms[5][256+i] = sineTable[i*2];
waveforms[5][512+i] = waveforms[5][768+i] = 0;
}
// 7th: square wave
for(i=0; i<512; i++) {
waveforms[6][i] = 1;
waveforms[6][512+i] = -1;
}
// 8th: exponential
double x;
double xIncrement = 1 * 16.0 / 256.0;
for(i=0, x=0; i<512; i++, x+=xIncrement) {
waveforms[7][i] = pow(2.0,-x);
waveforms[7][1023-i] = -pow(2.0,-(x + 1/16.0));
}
}
void OperatorDataStruct::loaddBPowTable()
{
for (int i = 0; i < DB_TABLE_SIZE; ++i)
{
dbpow[i] = pow(10.0, -(i / DB_TABLE_RES) / 10.0);
}
}
void OperatorDataStruct::loadAttackTable()
{
for (int i = 0; i < ATTACK_TABLE_SIZE; ++i)
{
attackTable[i] = -pow(2.0, ATTACK_MIN + i * ATTACK_RES);
}
}
void OPL3::Reset()
{
}
void OPL3::WriteReg(int reg, int v)
{
write(reg >> 8, reg & 0xFF, v);
}
void OPL3::SetPanning(int c, float left, float right)
{
if (FullPan)
{
Channel *channel;
if (c < 9)
{
channel = channels[0][c];
}
else
{
channel = channels[1][c - 9];
}
channel->leftPan = left;
channel->rightPan = right;
}
}
} // JavaOPL3
OPLEmul *JavaOPLCreate(bool stereo)
{
return new JavaOPL3::OPL3(stereo);
}
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