OPLL: fix per-channel osc, part 1

extern/Nuked-OPLL/opll.c

@@ -1019,6 +1019,10 @@ static void OPLL_Operator(opll_t *chip) {
     }
 
     chip->ch_out = ismod1 ? routput : (output>>3);
+
+    if (!ismod1) {
+      chip->output_ch[(chip->cycles+1)%9] = chip->ch_out;
+    }
 }
 
 static void OPLL_DoRhythm(opll_t *chip) {

extern/Nuked-OPLL/opll.h

@@ -191,6 +191,8 @@ typedef struct {
     int16_t output_m;
     int16_t output_r;
 
+    int16_t output_ch[9];
+
 } opll_t;
 
 const opll_patch_t* OPLL_GetPatchROM(uint32_t chip_type);

src/engine/platform/opll.cpp

@@ -97,6 +97,10 @@ const unsigned char drumSlot[11]={
   0, 0, 0, 0, 0, 0, 6, 7, 8, 8, 7
 };
 
+const unsigned char visMapOPLL[9]={
+  6, 7, 8, 3, 4, 5, 0, 1, 2
+};
+
 void DivPlatformOPLL::acquire_nuked(short* bufL, short* bufR, size_t start, size_t len) {
   static int o[2];
   static int os;
@@ -124,10 +128,18 @@ void DivPlatformOPLL::acquire_nuked(short* bufL, short* bufR, size_t start, size
       OPLL_Clock(&fm,o);
       unsigned char nextOut=cycleMapOPLL[fm.cycles];
       if ((nextOut>=6 && properDrums) || !isMuted[nextOut]) {
-        oscBuf[nextOut]->data[oscBuf[nextOut]->needle++]=(o[0]+o[1])<<6;
         os+=(o[0]+o[1]);
+        if (vrc7) oscBuf[nextOut]->data[oscBuf[nextOut]->needle++]=(o[0]+o[1])<<6;
       } else {
-        oscBuf[nextOut]->data[oscBuf[nextOut]->needle++]=0;
+        if (vrc7) oscBuf[nextOut]->data[oscBuf[nextOut]->needle++]=0;
+      }
+    }
+    if (!vrc7) for (int i=0; i<9; i++) {
+      unsigned char ch=visMapOPLL[i];
+      if ((i>=6 && properDrums) || !isMuted[ch]) {
+        oscBuf[ch]->data[oscBuf[ch]->needle++]=(fm.output_ch[i])<<6;
+      } else {
+        oscBuf[ch]->data[oscBuf[ch]->needle++]=0;
       }
     }
     os*=50;