dev168 - new behavior for porta in C64

papers/format.md

@@ -348,7 +348,8 @@ size | description
  --- | **a couple more compat flags** (>=138)
   1  | broken portamento during legato
   1  | broken macro during note off in some FM chips (>=155)
-  6  | reserved
+  1  | pre note (C64) does not compensate for portamento or legato (>=168)
+  5  | reserved
  --- | **speed pattern of first song** (>=139)
   1  | length of speed pattern (fail if this is lower than 0 or higher than 16)
  16  | speed pattern (this overrides speed 1 and speed 2 settings)

src/engine/engine.h

@@ -56,8 +56,8 @@
 
 #define DIV_UNSTABLE
 
-#define DIV_VERSION "dev167"
-#define DIV_ENGINE_VERSION 167
+#define DIV_VERSION "dev168"
+#define DIV_ENGINE_VERSION 168
 // for imports
 #define DIV_VERSION_MOD 0xff01
 #define DIV_VERSION_FC 0xff02

src/engine/fileOps.cpp

@@ -183,6 +183,7 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
       ds.brokenPortaArp=false;
       ds.snNoLowPeriods=true;
       ds.disableSampleMacro=true;
+      ds.preNoteNoEffect=true;
       ds.delayBehavior=0;
       ds.jumpTreatment=2;
 
@@ -1844,6 +1845,9 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
     if (ds.version<155) {
       ds.brokenFMOff=true;
     }
+    if (ds.version<168) {
+      ds.preNoteNoEffect=true;
+    }
     ds.isDMF=false;
 
     reader.readS(); // reserved
@@ -2355,7 +2359,12 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
       } else {
         reader.readC();
       }
-      for (int i=0; i<6; i++) {
+      if (ds.version>=168) {
+        ds.preNoteNoEffect=reader.readC();
+      } else {
+        reader.readC();
+      }
+      for (int i=0; i<5; i++) {
         reader.readC();
       }
     }
@@ -5383,7 +5392,9 @@ SafeWriter* DivEngine::saveFur(bool notPrimary, bool newPatternFormat) {
 
   // even more compat flags
   w->writeC(song.brokenPortaLegato);
-  for (int i=0; i<7; i++) {
+  w->writeC(song.brokenFMOff);
+  w->writeC(song.preNoteNoEffect);
+  for (int i=0; i<5; i++) {
     w->writeC(0);
   }
 

src/engine/playback.cpp

@@ -1208,8 +1208,26 @@ void DivEngine::nextRow() {
           if (disCont[dispatchOfChan[i]].dispatch!=NULL) {
             wantPreNote=disCont[dispatchOfChan[i]].dispatch->getWantPreNote();
             if (wantPreNote) {
+              bool doPreparePreNote=true;
               int addition=0;
+
               for (int j=0; j<curPat[i].effectCols; j++) {
+                if (!song.preNoteNoEffect) {
+                  if (pat->data[curRow][4+(j<<1)]==0x03) {
+                    doPreparePreNote=false;
+                    break;
+                  }
+                  if (pat->data[curRow][4+(j<<1)]==0x06) {
+                    doPreparePreNote=false;
+                    break;
+                  }
+                  if (pat->data[curRow][4+(j<<1)]==0xea) {
+                    if (pat->data[curRow][5+(j<<1)]>0) {
+                      doPreparePreNote=false;
+                      break;
+                    }
+                  }
+                }
                 if (pat->data[curRow][4+(j<<1)]==0xed) {
                   if (pat->data[curRow][5+(j<<1)]>0) {
                     addition=pat->data[curRow][5+(j<<1)]&255;
@@ -1217,7 +1235,7 @@ void DivEngine::nextRow() {
                   }
                 }
               }
-              dispatchCmd(DivCommand(DIV_CMD_PRE_NOTE,i,ticks+addition));
+              if (doPreparePreNote) dispatchCmd(DivCommand(DIV_CMD_PRE_NOTE,i,ticks+addition));
             }
           }
 

src/engine/song.h

@@ -375,6 +375,7 @@ struct DivSong {
   bool patchbayAuto;
   bool brokenPortaLegato;
   bool brokenFMOff;
+  bool preNoteNoEffect;
 
   std::vector<DivInstrument*> ins;
   std::vector<DivWavetable*> wave;
@@ -493,7 +494,8 @@ struct DivSong {
     oldArpStrategy(false),
     patchbayAuto(true),
     brokenPortaLegato(false),
-    brokenFMOff(false) {
+    brokenFMOff(false),
+    preNoteNoEffect(false) {
     for (int i=0; i<DIV_MAX_CHIPS; i++) {
       system[i]=DIV_SYSTEM_NULL;
       systemVol[i]=1.0;