mirrors/OPL
2
0
Fork 0
Code Activity
OPL/Source/hiopl.cpp
bsutherland 7d4af8c78d Bug fixes and visual tweaks.
2017-03-04 12:44:56 +09:00

311 lines
7.9 KiB
C++
Raw Blame History

#include "hiopl.h"
#include <assert.h>
#include "JuceHeader.h"
// A wrapper around the DOSBox and ZDoom OPL emulators.
Hiopl::Hiopl(Emulator emulator) {
//InitCaptureVariables();
adlib = new DBOPL::Handler();
//zdoom = JavaOPLCreate(false);
// channels reordered to match
// 'in-memory' order in DOSBox emulator
_op1offset[1] = 0x0;
_op1offset[2] = 0x1;
_op1offset[3] = 0x2;
_op1offset[4] = 0x8;
_op1offset[5] = 0x9;
_op1offset[6] = 0xa;
_op1offset[7] = 0x10;
_op1offset[8] = 0x11;
_op1offset[9] = 0x12;
_op2offset[1] = 0x3;
_op2offset[2] = 0x4;
_op2offset[3] = 0x5;
_op2offset[4] = 0xb;
_op2offset[5] = 0xc;
_op2offset[6] = 0xd;
_op2offset[7] = 0x13;
_op2offset[8] = 0x14;
_op2offset[9] = 0x15;
SetEmulator(emulator);
_ClearRegisters();
}
void Hiopl::_ClearRegisters() {
for (int i = 0; i < 256; i++) {
_WriteReg(i, 0);
}
}
void Hiopl::SetEmulator(Emulator emulator) {
this->emulator = emulator;
}
void Hiopl::Generate(int length, float* buffer) {
intermediateBufIdx = (intermediateBufIdx + 1) % INTERMEDIATE_BUF_N;
Bit32s *iBuf = intermediateBuf[intermediateBufIdx];
int fullCalls = length / 512; // the emulator is limited to 512 bytes per call
int c = 0;
for (; c < fullCalls; c++) {
adlib->Generate(512, iBuf + (c * 512));
}
// final (or only) call
if (length % 512 > 0) {
adlib->Generate(length % 512, iBuf + (c * 512));
}
for (int i = 0; i < length; i++) {
// Magic divisor taken from ZDoom wrapper for DOSBox emulator, line 892
// https://github.com/rheit/zdoom/blob/master/src/oplsynth/dosbox/opl.cpp
const float y = (float)(iBuf[i]) / 10240.0f;
// http://stackoverflow.com/questions/427477/fastest-way-to-clamp-a-real-fixed-floating-point-value
const float z = y < -1.0f ? -1.0f : y;
buffer[i] = z > 1.0f ? 1.0f : z;
}
//} else if (ZDOOM == emulator) {
// ZDoom hacked to write mono samples
// zdoom->Update(buffer, length);
//}
}
void Hiopl::SetSampleRate(int hz) {
adlib->Init(hz);
EnableWaveformControl();
for (int i = 0; i < OPL_N_REG; i++) {
adlib->WriteReg(i, regCache[i]);
}
}
void Hiopl::_WriteReg(Bit32u reg, Bit8u value, Bit8u mask) {
if (mask > 0) {
value = (regCache[reg] & (~mask)) | (value & mask);
}
// Write to the registers of both emulators.
//if (DOSBOX == emulator) {
adlib->WriteReg(reg, value);
//} else if (ZDOOM == emulator) {
// zdoom->WriteReg(reg, value);
//}
regCache[reg] = value;
}
Bit8u Hiopl::_ReadReg(Bit32u reg) {
return regCache[reg];
}
void Hiopl::_ClearRegBits(Bit32u reg, Bit8u mask) {
_WriteReg(reg, regCache[reg] & ~mask);
}
void Hiopl::EnableWaveformControl() {
_WriteReg(0x01, 0x20);
}
void Hiopl::SetWaveform(int ch, int osc, Waveform wave) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0xe0+offset, (Bit8u)wave, 0x7);
}
void Hiopl::SetAttenuation(int ch, int osc, int level) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x40+offset, (Bit8u)level, 0x3f);
}
void Hiopl::SetKsl(int ch, int osc, int level) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x40+offset, (Bit8u)(level<<6), 0xc0);
}
void Hiopl::SetFrequencyMultiple(int ch, int osc, FreqMultiple mult) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x20+offset, (Bit8u)mult, 0xf);
}
void Hiopl::SetEnvelopeAttack(int ch, int osc, int t) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x60+offset, (Bit8u)t<<4, 0xf0);
}
void Hiopl::SetEnvelopeDecay(int ch, int osc, int t) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x60+offset, (Bit8u)t, 0x0f);
}
void Hiopl::SetEnvelopeSustain(int ch, int osc, int level) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x80+offset, (Bit8u)level<<4, 0xf0);
}
void Hiopl::SetEnvelopeRelease(int ch, int osc, int t) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x80+offset, (Bit8u)t, 0x0f);
}
void Hiopl::EnableTremolo(int ch, int osc, bool enable) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x20+offset, enable ? 0x80 : 0x0, 0x80);
}
void Hiopl::EnableVibrato(int ch, int osc, bool enable) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x20+offset, enable ? 0x40 : 0x0, 0x40);
}
void Hiopl::TremoloDepth(bool high) {
_WriteReg(0xbd, high ? 0x80 : 0x0, 0x80);
}
void Hiopl::VibratoDepth(bool high) {
_WriteReg(0xbd, high ? 0x40 : 0x0, 0x40);
}
void Hiopl::EnableSustain(int ch, int osc, bool enable) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x20+offset, enable ? 0x20 : 0x0, 0x20);
}
void Hiopl::EnableKsr(int ch, int osc, bool enable) {
int offset = this->_GetOffset(ch, osc);
_WriteReg(0x20+offset, enable ? 0x10 : 0x0, 0x10);
}
void Hiopl::EnableAdditiveSynthesis(int ch, bool enable) {
int offset = this->_GetOffset(ch);
_WriteReg(0xc0+offset, enable ? 0x1 : 0x0, 0x1);
}
void Hiopl::SetModulatorFeedback(int ch, int level) {
int offset = this->_GetOffset(ch);
_WriteReg(0xc0+offset, (Bit8u)level << 1, 0x0e);
}
void Hiopl::SetPercussionMode(bool enable) {
_WriteReg(0xbd, enable ? 0x20 : 0x0, 0x20);
}
void Hiopl::HitPercussion(Drum drum) {
Bit8u mask = (Bit8u)drum;
_WriteReg(0xbd, mask, mask);
}
void Hiopl::ReleasePercussion() {
_WriteReg(0xbd, 0x0, 0x1f);
}
void Hiopl::KeyOn(int ch, float frqHz) {
Hiopl::SetFrequency(ch, frqHz, true);
}
void Hiopl::KeyOff(int ch) {
int offset = this->_GetOffset(ch);
_ClearRegBits(0xb0+offset, 0x20);
}
static const char* STATE[] = {
"-",
"R",
"S",
"D",
"A",
};
// in-memory ordering of DOSBox emulator
static int DOSBOX_CH_MAP[] = {
-1, // channel numbering starts at 1
0,
2, // 1
4, // 2
1, // 3
3, // 4
5,
6,
7,
8,
9,
};
const char* Hiopl::GetState(int ch) const {
int dosboxCh = DOSBOX_CH_MAP[ch];
return STATE[adlib->chip.chan[dosboxCh].op[1].state];
}
bool Hiopl::IsActive(int ch) {
// check carrier envelope state
return DBOPL::Operator::State::OFF != adlib->chip.chan[ch - 1].op[1].state;
}
void Hiopl::SetFrequency(int ch, float frqHz, bool keyOn) {
unsigned int fnum, block;
int offset = this->_GetOffset(ch);
// ZDoom emulator seems to be tuned down by two semitones for some reason. Sample rate difference?
//if (ZDOOM == emulator) {
// frqHz *= 1.122461363636364f;
//}
_milliHertzToFnum((unsigned int)(frqHz * 1000.0), &fnum, &block);
_WriteReg(0xa0+offset, fnum % 0x100);
uint8 trig = (regCache[0xb0+offset] & 0x20) | (keyOn ? 0x20 : 0x00);
_WriteReg(0xb0+offset, trig|((block&0x7)<<2)|(0x3&(fnum/0x100)));
}
// from libgamemusic, opl-util.cpp
void Hiopl::_milliHertzToFnum(unsigned int milliHertz,
unsigned int *fnum, unsigned int *block, unsigned int conversionFactor)
{
// Special case to avoid divide by zero
if (milliHertz == 0) {
*block = 0; // actually any block will work
*fnum = 0;
return;
}
// Special case for frequencies too high to produce
if (milliHertz > 6208431) {
*block = 7;
*fnum = 1023;
return;
}
// This is a bit more efficient and doesn't need log2() from math.h
if (milliHertz > 3104215) *block = 7;
else if (milliHertz > 1552107) *block = 6;
else if (milliHertz > 776053) *block = 5;
else if (milliHertz > 388026) *block = 4;
else if (milliHertz > 194013) *block = 3;
else if (milliHertz > 97006) *block = 2;
else if (milliHertz > 48503) *block = 1;
else *block = 0;
// Slightly more efficient version
*fnum = (unsigned int)(((unsigned long long)milliHertz << (20 - *block)) / (conversionFactor * 1000.0) + 0.5);
if ((*block == 7) && (*fnum > 1023)) {
// frequency out of range, clipping to maximum value.
*fnum = 1023;
}
assert(*block <= 7);
assert(*fnum < 1024);
return;
}
Hiopl::~Hiopl() {
};
// Check that _GetOffset parameters are in range.
bool Hiopl::_CheckParams(int ch, int osc=OSCILLATORS) {
return ch > 0 && ch <= CHANNELS && osc > 0 && osc <= OSCILLATORS;
}
// The register offset for parameters that affect a specific oscillator.
int Hiopl::_GetOffset(int ch, int osc) {
assert(_CheckParams(ch, osc));
return (1 == osc) ? _op1offset[ch] : _op2offset[ch];
}
// The register offset for parameters that affect the entire channel.
int Hiopl::_GetOffset(int ch) {
assert(_CheckParams(ch));
return ch - 1;
}
View git blame Copy permalink