G E N E S I S

without SN

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "extern/Nuked-OPN2"]
+	path = extern/Nuked-OPN2
+	url = https://github.com/nukeykt/Nuked-OPN2

CMakeLists.txt

@@ -23,11 +23,15 @@ endif()
 
 set(ENGINE_SOURCES
 src/log.cpp
+
+extern/Nuked-OPN2/ym3438.c
+
 src/engine/blip_buf.c
 src/engine/safeReader.cpp
 src/engine/engine.cpp
 src/engine/playback.cpp
 src/engine/platform/abstract.cpp
+src/engine/platform/genesis.cpp
 src/engine/platform/dummy.cpp)
 
 #imgui/imgui.cpp

extern/Nuked-OPN2

@@ -0,0 +1 @@
+Subproject commit 64704a443f8f6c1906ba26297092ea70fa1d45d7

src/engine/engine.cpp

@@ -2,6 +2,7 @@
 #include "safeReader.h"
 #include "../ta-log.h"
 #include "../audio/sdl.h"
+#include "platform/genesis.h"
 #include "platform/dummy.h"
 #include <zlib.h>
 
@@ -636,7 +637,14 @@ bool DivEngine::init() {
   bbOut[0]=new short[got.bufsize];
   bbOut[1]=new short[got.bufsize];
 
-  dispatch=new DivPlatformDummy;
+  switch (song.system) {
+    case DIV_SYSTEM_GENESIS:
+      dispatch=new DivPlatformGenesis;
+      break;
+    default:
+      dispatch=new DivPlatformDummy;
+      break;
+  }
   dispatch->init(this,getChannelCount(song.system),got.rate);
 
   blip_set_rates(bb[0],dispatch->rate,got.rate);

src/engine/engine.h

@@ -14,7 +14,6 @@ struct DivChannelState {
 };
 
 class DivEngine {
-  DivSong song;
   DivDispatch* dispatch;
   TAAudio* output;
   TAAudioDesc want, got;
@@ -34,6 +33,7 @@ class DivEngine {
   void nextTick();
 
   public:
+    DivSong song;
     void nextBuf(float** in, float** out, int inChans, int outChans, unsigned int size);
     // load a .dmf.
     bool load(void* f, size_t length);

src/engine/instrument.h

@@ -1,3 +1,5 @@
+#include "../ta-utils.h"
+
 enum DivInstrumentType {
   DIV_INS_FM,
   DIV_INS_STD,
@@ -7,7 +9,7 @@ enum DivInstrumentType {
 
 struct DivInstrumentFM {
   unsigned char alg, fb, fms, ams, ops;
-  struct {
+  struct Operator {
     unsigned char am, ar, dr, mult, rr, sl, tl, dt2, rs, dt, d2r, ssgEnv;
     unsigned char dam, dvb, egt, ksl, sus, vib, ws, ksr; // YMU759
   } op[4];

src/engine/platform/dummy.cpp

@@ -13,21 +13,20 @@ void DivPlatformDummy::acquire(short& l, short& r) {
 }
 
 void DivPlatformDummy::tick() {
-  for (unsigned char i=0; i<chans; i++) {
-    chan[i].vol=chan[i].vol-(chan[i].vol>>3);
-  }
 }
 
 int DivPlatformDummy::dispatch(DivCommand c) {
   switch (c.cmd) {
     case DIV_CMD_NOTE_ON:
-      chan[c.chan].vol=0x7f;
       chan[c.chan].freq=16.4f*pow(2.0f,((float)c.value/12.0f));
       chan[c.chan].active=true;
       break;
     case DIV_CMD_NOTE_OFF:
       chan[c.chan].active=false;
       break;
+    case DIV_CMD_VOLUME:
+      chan[c.chan].vol=c.value;
+      break;
     default:
       break;
   }
@@ -38,5 +37,8 @@ int DivPlatformDummy::init(DivEngine* p, int channels, int sugRate) {
   parent=p;
   rate=65536;
   chans=channels;
+  for (int i=0; i<chans; i++) {
+    chan[i].vol=0x0f;
+  }
   return channels;
 }

src/engine/platform/genesis.cpp

@@ -0,0 +1,88 @@
+#include "genesis.h"
+#include "../engine.h"
+#include <string.h>
+
+// TODO fix all the writes.
+// i think there is no wait for data writes, just for ON/OFF writes
+void DivPlatformGenesis::acquire(short& l, short& r) {
+  short o[2];
+  if (!writes.empty() && --delay<0) {
+    QueuedWrite w=writes.front();
+    //printf("write: %x = %.2x\n",w.addr,w.val);
+    OPN2_Write(&fm,0x0+((w.addr>>8)<<1),w.addr);
+    OPN2_Clock(&fm,o);
+    OPN2_Write(&fm,0x1+((w.addr>>8)<<1),w.val);
+    writes.pop();
+    delay=24;
+  }
+  OPN2_Clock(&fm,o);
+  //OPN2_Write(&fm,0,0);
+  l=o[0]<<7;
+  r=o[1]<<7;
+}
+
+void DivPlatformGenesis::tick() {
+}
+
+static unsigned short chanOffs[6]={
+  0x00, 0x01, 0x02, 0x100, 0x101, 0x102
+};
+static unsigned short opOffs[4]={
+  0x00, 0x04, 0x08, 0x0c
+};
+static unsigned char konOffs[6]={
+  0, 1, 2, 4, 5, 6
+};
+static unsigned short notes[12]={
+  644,681,722,765,810,858,910,964,1021,1081,1146,1214
+};
+
+int DivPlatformGenesis::dispatch(DivCommand c) {
+  switch (c.cmd) {
+    case DIV_CMD_NOTE_ON: {
+      if (c.chan>5) break;
+      //chan[c.chan].freq=16.4f*pow(2.0f,((float)c.value/12.0f));
+      DivInstrument* ins=parent->song.ins[chan[c.chan].ins];
+      writes.emplace(0x28,0x00|konOffs[c.chan]);
+      for (int i=0; i<4; i++) {
+        unsigned short baseAddr=chanOffs[c.chan]|opOffs[i];
+        DivInstrumentFM::Operator op=ins->fm.op[i];
+        writes.emplace(baseAddr+0x30,op.mult&15|(op.dt<<4));
+        writes.emplace(baseAddr+0x40,op.tl);
+        writes.emplace(baseAddr+0x50,op.ar&31|(op.rs<<6));
+        writes.emplace(baseAddr+0x60,op.dr&31|(op.am<<7));
+        writes.emplace(baseAddr+0x70,op.d2r&31);
+        writes.emplace(baseAddr+0x80,op.rr&15|(op.sl<<4));
+      }
+      writes.emplace(chanOffs[c.chan]+0xa4,((c.value/12)<<3)|(notes[c.value%12]>>8));
+      writes.emplace(chanOffs[c.chan]+0xa0,notes[c.value%12]);
+      writes.emplace(chanOffs[c.chan]+0xb0,ins->fm.alg&7|(ins->fm.fb<<3));
+      writes.emplace(chanOffs[c.chan]+0xb4,0xc0|ins->fm.fms&7|((ins->fm.ams&3)<<4));
+      writes.emplace(0x28,0xf0|konOffs[c.chan]);
+      chan[c.chan].active=true;
+      break;
+    }
+    case DIV_CMD_NOTE_OFF:
+      writes.emplace(0x28,0x00|konOffs[c.chan]);
+      chan[c.chan].active=false;
+      break;
+    case DIV_CMD_VOLUME:
+      chan[c.chan].vol=c.value;
+      break;
+    case DIV_CMD_INSTRUMENT:
+      chan[c.chan].ins=c.value;
+      break;
+    default:
+      break;
+  }
+  return 1;
+}
+
+int DivPlatformGenesis::init(DivEngine* p, int channels, int sugRate) {
+  parent=p;
+  rate=1278409;
+  OPN2_Reset(&fm);
+  
+  delay=100;
+  return 10;
+}

src/engine/platform/genesis.h

@@ -0,0 +1,28 @@
+#include "../dispatch.h"
+#include <queue>
+#include "../../../extern/Nuked-OPN2/ym3438.h"
+
+class DivPlatformGenesis: public DivDispatch {
+  struct Channel {
+    unsigned short freq;
+    unsigned char ins;
+    bool active;
+    signed char vol;
+    Channel(): freq(0), ins(0), active(false), vol(0) {}
+  };
+  Channel chan[10];
+  struct QueuedWrite {
+    unsigned short addr;
+    unsigned char val;
+    QueuedWrite(unsigned short a, unsigned char v): addr(a), val(v) {}
+  };
+  std::queue<QueuedWrite> writes;
+  ym3438_t fm;
+  int psg;
+  int delay;
+  public:
+    void acquire(short& l, short& r);
+    int dispatch(DivCommand c);
+    void tick();
+    int init(DivEngine* parent, int channels, int sugRate);
+};

src/engine/playback.cpp

@@ -79,6 +79,10 @@ void DivEngine::nextRow() {
 
   for (int i=0; i<chans; i++) {
     DivPattern* pat=song.pat[i]->data[curOrder];
+    // instrument
+    if (pat->data[curRow][2]!=255) {
+      dispatch->dispatch(DivCommand(DIV_CMD_INSTRUMENT,i,pat->data[curRow][2]));
+    }
     // note
     if (pat->data[curRow][0]==100) {
       dispatch->dispatch(DivCommand(DIV_CMD_NOTE_OFF,i));
@@ -86,6 +90,11 @@ void DivEngine::nextRow() {
       dispatch->dispatch(DivCommand(DIV_CMD_NOTE_ON,i,pat->data[curRow][0]+pat->data[curRow][1]*12));
     }
 
+    // volume
+    if (pat->data[curRow][3]!=255) {
+      dispatch->dispatch(DivCommand(DIV_CMD_VOLUME,i,pat->data[curRow][3]));
+    }
+
     // effects
     for (int j=0; j<song.pat[i]->effectRows; j++) {
       unsigned char effect=pat->data[curRow][4+(j<<1)];

src/engine/song.h

@@ -63,8 +63,9 @@ struct DivSong {
   //   - introduces Genesis system
   //   - introduces system number
   // - 7: ???
-  // - 5: ???
-  // - 3: BETA 3 (?)
+  // - 5: BETA 3 (?)
+  //   - adds arpeggio tick
+  // - 3: BETA 2
   //   - possibly the first version that could save
   //   - basic format, no system number, 16 instruments, one speed, YMU759-only
   //   - if somebody manages to find a version 2 or even 1 module, please tell me as it will be worth more than a luxury vehicle