furnace/src/engine/platform/vic20.cpp

373 lines
10 KiB
C++

/**
* Furnace Tracker - multi-system chiptune tracker
* Copyright (C) 2021-2023 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.
*/
#include "vic20.h"
#include "../engine.h"
#include "../../ta-log.h"
#include <math.h>
#define rWrite(a,v) {regPool[(a)]=(v)&0xff; vic_sound_machine_store(vic,a,(v)&0xff);}
#define CHIP_DIVIDER 32
#define SAMP_DIVIDER 4
const char* regCheatSheetVIC[]={
"CH1_Pitch", "0A",
"CH2_Pitch", "0B",
"CH3_Pitch", "0C",
"Noise_Pitch", "0D",
"Volume", "0E",
NULL
};
const char** DivPlatformVIC20::getRegisterSheet() {
return regCheatSheetVIC;
}
void DivPlatformVIC20::acquire(short** buf, size_t len) {
const unsigned char loadFreq[3] = {0x7e, 0x7d, 0x7b};
const unsigned char wavePatterns[16] = {
0b0, 0b10, 0b100, 0b110, 0b1000, 0b1010, 0b1011, 0b1110,
0b10010, 0b10100, 0b10110, 0b11000, 0b11010, 0b100100, 0b101010, 0b101100
};
for (size_t h=0; h<len; h++) {
if (hasWaveWrite) {
hasWaveWrite=false;
for (int i=0; i<3; i++) {
if (chan[i].waveWriteCycle>=0) {
if (chan[i].waveWriteCycle>=16*7) {
// empty shift register first
rWrite(10+i,126);
} else if (chan[i].waveWriteCycle>=16) {
unsigned bit=8-(chan[i].waveWriteCycle/16);
rWrite(10+i,loadFreq[i]|((wavePatterns[chan[i].wave]<<bit)&0x80));
} else {
rWrite(10+i,255-chan[i].freq);
}
chan[i].waveWriteCycle-=SAMP_DIVIDER;
hasWaveWrite=true;
}
}
}
short samp;
vic_sound_machine_calculate_samples(vic,&samp,1,1,0,SAMP_DIVIDER);
buf[0][h]=samp;
for (int i=0; i<4; i++) {
oscBuf[i]->data[oscBuf[i]->needle++]=vic->ch[i].out?(vic->volume<<11):0;
}
}
}
void DivPlatformVIC20::calcAndWriteOutVol(int ch, int env) {
chan[ch].outVol=MIN(chan[ch].vol*env/15,15);
writeOutVol(ch);
}
void DivPlatformVIC20::writeOutVol(int ch) {
rWrite(14,chan[ch].outVol);
}
void DivPlatformVIC20::tick(bool sysTick) {
for (int i=0; i<4; i++) {
chan[i].std.next();
if (chan[i].std.vol.had) {
int env=chan[i].std.vol.val;
calcAndWriteOutVol(i,env);
}
if (NEW_ARP_STRAT) {
chan[i].handleArp();
} else if (chan[i].std.arp.had) {
if (!chan[i].inPorta) {
chan[i].baseFreq=NOTE_PERIODIC(parent->calcArp(chan[i].note,chan[i].std.arp.val));
}
chan[i].freqChanged=true;
}
if (chan[i].std.duty.had) {
if (chan[i].onOff!=(bool)chan[i].std.duty.val) {
chan[i].onOff=(bool)chan[i].std.duty.val;
if (chan[i].active) {
if (chan[i].onOff) {
chan[i].keyOn=true;
chan[i].keyOff=false;
} else {
chan[i].keyOn=false;
chan[i].keyOff=true;
}
}
}
}
if (chan[i].std.wave.had) {
if (chan[i].wave!=chan[i].std.wave.val) {
chan[i].wave=chan[i].std.wave.val&0x0f;
chan[i].keyOn=true;
}
}
if (chan[i].std.pitch.had) {
if (chan[i].std.pitch.mode) {
chan[i].pitch2+=chan[i].std.pitch.val;
CLAMP_VAR(chan[i].pitch2,-32768,32767);
} else {
chan[i].pitch2=chan[i].std.pitch.val;
}
chan[i].freqChanged=true;
}
if (chan[i].freqChanged || chan[i].keyOn || chan[i].keyOff) {
chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,chan[i].fixedArp?chan[i].baseNoteOverride:chan[i].arpOff,chan[i].fixedArp,true,0,chan[i].pitch2,chipClock,CHIP_DIVIDER);
if (i<3) {
chan[i].freq>>=(2-i);
} else {
chan[i].freq>>=1;
}
if (chan[i].freq<1) chan[i].freq=1;
if (chan[i].freq>127) chan[i].freq=0;
if (isMuted[i]) chan[i].keyOn=false;
if (chan[i].keyOn) {
if (i<3) {
// 128*16 cycles for lowest channel to finish counting at lowest freq
// 2*16 cycles for lowest channel to empty first 2 bits
// 7*16 cycles to write 7 bits
chan[i].waveWriteCycle=137*16-1;
hasWaveWrite=true;
} else {
rWrite(10+i,255-chan[i].freq);
}
chan[i].keyOn=false;
} else if (chan[i].freqChanged && chan[i].active && !isMuted[i]) {
rWrite(10+i,255-chan[i].freq);
}
if (chan[i].keyOff) {
rWrite(10+i,0);
chan[i].keyOff=false;
}
chan[i].freqChanged=false;
}
}
}
int DivPlatformVIC20::dispatch(DivCommand c) {
switch (c.cmd) {
case DIV_CMD_NOTE_ON: {
DivInstrument* ins=parent->getIns(chan[c.chan].ins,DIV_INS_VIC);
if (c.value!=DIV_NOTE_NULL) {
chan[c.chan].baseFreq=NOTE_PERIODIC(c.value);
chan[c.chan].freqChanged=true;
chan[c.chan].note=c.value;
}
chan[c.chan].onOff=true;
chan[c.chan].active=true;
chan[c.chan].keyOn=true;
chan[c.chan].macroInit(ins);
break;
}
case DIV_CMD_NOTE_OFF:
chan[c.chan].active=false;
chan[c.chan].keyOff=true;
chan[c.chan].macroInit(NULL);
break;
case DIV_CMD_NOTE_OFF_ENV:
case DIV_CMD_ENV_RELEASE:
chan[c.chan].std.release();
break;
case DIV_CMD_INSTRUMENT:
if (chan[c.chan].ins!=c.value || c.value2==1) {
chan[c.chan].ins=c.value;
}
break;
case DIV_CMD_VOLUME:
if (chan[c.chan].vol!=c.value) {
chan[c.chan].vol=c.value;
if (!chan[c.chan].std.vol.has) {
calcAndWriteOutVol(c.chan,15);
}
}
break;
case DIV_CMD_GET_VOLUME:
return chan[c.chan].vol;
break;
case DIV_CMD_PITCH:
chan[c.chan].pitch=c.value;
chan[c.chan].freqChanged=true;
break;
case DIV_CMD_WAVE:
chan[c.chan].wave=c.value&0x0f;
chan[c.chan].keyOn=true;
break;
case DIV_CMD_NOTE_PORTA: {
int destFreq=NOTE_PERIODIC(c.value2);
bool return2=false;
if (destFreq>chan[c.chan].baseFreq) {
chan[c.chan].baseFreq+=c.value;
if (chan[c.chan].baseFreq>=destFreq) {
chan[c.chan].baseFreq=destFreq;
return2=true;
}
} else {
chan[c.chan].baseFreq-=c.value;
if (chan[c.chan].baseFreq<=destFreq) {
chan[c.chan].baseFreq=destFreq;
return2=true;
}
}
chan[c.chan].freqChanged=true;
if (return2) {
chan[c.chan].inPorta=false;
return 2;
}
break;
}
case DIV_CMD_LEGATO:
chan[c.chan].baseFreq=NOTE_PERIODIC(c.value+((HACKY_LEGATO_MESS)?(chan[c.chan].std.arp.val):(0)));
chan[c.chan].freqChanged=true;
chan[c.chan].note=c.value;
break;
case DIV_CMD_PRE_PORTA:
if (chan[c.chan].active && c.value2) {
if (parent->song.resetMacroOnPorta) chan[c.chan].macroInit(parent->getIns(chan[c.chan].ins,DIV_INS_VIC));
}
if (!chan[c.chan].inPorta && c.value && !parent->song.brokenPortaArp && chan[c.chan].std.arp.will && !NEW_ARP_STRAT) chan[c.chan].baseFreq=NOTE_PERIODIC(chan[c.chan].note);
chan[c.chan].inPorta=c.value;
break;
case DIV_CMD_GET_VOLMAX:
return 15;
break;
case DIV_CMD_MACRO_OFF:
chan[c.chan].std.mask(c.value,true);
break;
case DIV_CMD_MACRO_ON:
chan[c.chan].std.mask(c.value,false);
break;
case DIV_ALWAYS_SET_VOLUME:
return 1;
break;
default:
break;
}
return 1;
}
void DivPlatformVIC20::muteChannel(int ch, bool mute) {
isMuted[ch]=mute;
if (mute) {
chan[ch].keyOff=true;
} else if (chan[ch].active) {
chan[ch].keyOn=true;
}
}
void DivPlatformVIC20::forceIns() {
for (int i=0; i<4; i++) {
chan[i].insChanged=true;
chan[i].freqChanged=true;
writeOutVol(i);
}
}
bool DivPlatformVIC20::isVolGlobal() {
return true;
}
void* DivPlatformVIC20::getChanState(int ch) {
return &chan[ch];
}
DivMacroInt* DivPlatformVIC20::getChanMacroInt(int ch) {
return &chan[ch].std;
}
DivDispatchOscBuffer* DivPlatformVIC20::getOscBuffer(int ch) {
return oscBuf[ch];
}
unsigned char* DivPlatformVIC20::getRegisterPool() {
return regPool;
}
int DivPlatformVIC20::getRegisterPoolSize() {
return 16;
}
void DivPlatformVIC20::reset() {
memset(regPool,0,16);
for (int i=0; i<4; i++) {
chan[i]=Channel();
chan[i].std.setEngine(parent);
}
vic_sound_machine_init(vic,rate,chipClock);
hasWaveWrite=false;
rWrite(14,15);
// hack: starting noise channel right away after this would result in a dead
// channel as the LFSR state is 0, so clock it a bit
vic_sound_clock(vic,4);
}
int DivPlatformVIC20::getOutputCount() {
return 1;
}
void DivPlatformVIC20::notifyInsDeletion(void* ins) {
for (int i=0; i<4; i++) {
chan[i].std.notifyInsDeletion((DivInstrument*)ins);
}
}
void DivPlatformVIC20::setFlags(const DivConfig& flags) {
if (flags.getInt("clockSel",0)) {
chipClock=COLOR_PAL/4.0;
} else {
chipClock=COLOR_NTSC*2.0/7.0;
}
CHECK_CUSTOM_CLOCK;
rate=chipClock/4;
for (int i=0; i<4; i++) {
oscBuf[i]->rate=rate;
}
}
void DivPlatformVIC20::poke(unsigned int addr, unsigned short val) {
rWrite(addr,val);
}
void DivPlatformVIC20::poke(std::vector<DivRegWrite>& wlist) {
for (DivRegWrite& i: wlist) rWrite(i.addr,i.val);
}
int DivPlatformVIC20::init(DivEngine* p, int channels, int sugRate, const DivConfig& flags) {
parent=p;
dumpWrites=false;
skipRegisterWrites=false;
for (int i=0; i<4; i++) {
isMuted[i]=false;
oscBuf[i]=new DivDispatchOscBuffer;
}
setFlags(flags);
vic=new sound_vic20_t();
reset();
return 4;
}
void DivPlatformVIC20::quit() {
for (int i=0; i<4; i++) {
delete oscBuf[i];
}
delete vic;
}
DivPlatformVIC20::~DivPlatformVIC20() {
}