From 8db53faf720800d769fcbddbb564a24d33e34ccd Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Fri, 22 Apr 2022 04:23:52 -0500
Subject: [PATCH 01/46] new FM frequency calculation experiments

---
 src/engine/dispatch.h              |  1 +
 src/engine/platform/genesis.cpp    | 78 +++++++++---------------------
 src/engine/platform/genesis.h      |  3 --
 src/engine/platform/genesisext.cpp | 66 +++++++++++--------------
 4 files changed, 51 insertions(+), 97 deletions(-)

diff --git a/src/engine/dispatch.h b/src/engine/dispatch.h
index c35ff919..b358c464 100644
--- a/src/engine/dispatch.h
+++ b/src/engine/dispatch.h
@@ -426,6 +426,7 @@ class DivDispatch {
 #define NOTE_PERIODIC(x) round(parent->calcBaseFreq(chipClock,CHIP_DIVIDER,x,true))
 #define NOTE_PERIODIC_NOROUND(x) parent->calcBaseFreq(chipClock,CHIP_DIVIDER,x,true)
 #define NOTE_FREQUENCY(x) parent->calcBaseFreq(chipClock,CHIP_FREQBASE,x,false)
+#define NOTE_FNUM_BLOCK(x,bits) ((((int)parent->calcBaseFreq(chipClock,CHIP_FREQBASE,(x)%12,false))&((1<<bits)-1))|((MAX(x,0)/12)<<bits))
 
 #define COLOR_NTSC (315000000.0/88.0)
 #define COLOR_PAL (283.75*15625.0+25.0)
diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 81fcdefe..80dac1d4 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -245,15 +245,15 @@ void DivPlatformGenesis::tick(bool sysTick) {
     if (chan[i].std.arp.had) {
       if (!chan[i].inPorta) {
         if (chan[i].std.arp.mode) {
-          chan[i].baseFreq=NOTE_FREQUENCY(chan[i].std.arp.val);
+          chan[i].baseFreq=NOTE_FNUM_BLOCK(chan[i].std.arp.val,11);
         } else {
-          chan[i].baseFreq=NOTE_FREQUENCY(chan[i].note+(signed char)chan[i].std.arp.val);
+          chan[i].baseFreq=NOTE_FNUM_BLOCK(chan[i].note+(signed char)chan[i].std.arp.val,11);
         }
       }
       chan[i].freqChanged=true;
     } else {
       if (chan[i].std.arp.mode && chan[i].std.arp.finished) {
-        chan[i].baseFreq=NOTE_FREQUENCY(chan[i].note);
+        chan[i].baseFreq=NOTE_FNUM_BLOCK(chan[i].note,11);
         chan[i].freqChanged=true;
       }
     }
@@ -394,9 +394,9 @@ void DivPlatformGenesis::tick(bool sysTick) {
   for (int i=0; i<6; i++) {
     if (i==2 && extMode) continue;
     if (chan[i].freqChanged) {
-      chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,false,octave(chan[i].baseFreq));
-      if (chan[i].freq>262143) chan[i].freq=262143;
-      int freqt=toFreq(chan[i].freq)+chan[i].std.pitch.val;
+      chan[i].freq=((chan[i].baseFreq&0xf800)|parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false))+chan[i].std.pitch.val;
+      if (chan[i].freq>65535) chan[i].freq=65535;
+      int freqt=chan[i].freq;
       immWrite(chanOffs[i]+ADDR_FREQH,freqt>>8);
       immWrite(chanOffs[i]+ADDR_FREQ,freqt&0xff);
       if (chan[i].furnaceDac && dacMode) {
@@ -422,47 +422,6 @@ void DivPlatformGenesis::tick(bool sysTick) {
   }
 }
 
-int DivPlatformGenesis::octave(int freq) {
-  if (freq>=82432) {
-    return 128;
-  } else if (freq>=41216) {
-    return 64;
-  } else if (freq>=20608) {
-    return 32;
-  } else if (freq>=10304) {
-    return 16;
-  } else if (freq>=5152) {
-    return 8;
-  } else if (freq>=2576) {
-    return 4;
-  } else if (freq>=1288) {
-    return 2;
-  } else {
-    return 1;
-  }
-  return 1;
-}
-
-int DivPlatformGenesis::toFreq(int freq) {
-  if (freq>=82432) {
-    return 0x3800|((freq>>7)&0x7ff);
-  } else if (freq>=41216) {
-    return 0x3000|((freq>>6)&0x7ff);
-  } else if (freq>=20608) {
-    return 0x2800|((freq>>5)&0x7ff);
-  } else if (freq>=10304) {
-    return 0x2000|((freq>>4)&0x7ff);
-  } else if (freq>=5152) {
-    return 0x1800|((freq>>3)&0x7ff);
-  } else if (freq>=2576) {
-    return 0x1000|((freq>>2)&0x7ff);
-  } else if (freq>=1288) {
-    return 0x800|((freq>>1)&0x7ff);
-  } else {
-    return freq&0x7ff;
-  }
-}
-
 void DivPlatformGenesis::muteChannel(int ch, bool mute) {
   isMuted[ch]=mute;
   for (int j=0; j<4; j++) {
@@ -509,7 +468,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
           dacPos=0;
           dacPeriod=0;
           if (c.value!=DIV_NOTE_NULL) {
-            chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value);
+            chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
             chan[c.chan].freqChanged=true;
           }
           chan[c.chan].furnaceDac=true;
@@ -576,7 +535,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       chan[c.chan].insChanged=false;
 
       if (c.value!=DIV_NOTE_NULL) {
-        chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value);
+        chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
         chan[c.chan].portaPause=false;
         chan[c.chan].note=c.value;
         chan[c.chan].freqChanged=true;
@@ -656,26 +615,33 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       break;
     }
     case DIV_CMD_NOTE_PORTA: {
-      int destFreq=NOTE_FREQUENCY(c.value2);
+      int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
       int newFreq;
       bool return2=false;
       if (destFreq>chan[c.chan].baseFreq) {
-        newFreq=chan[c.chan].baseFreq+c.value*octave(chan[c.chan].baseFreq);
+        newFreq=chan[c.chan].baseFreq+c.value;
         if (newFreq>=destFreq) {
           newFreq=destFreq;
           return2=true;
         }
       } else {
-        newFreq=chan[c.chan].baseFreq-c.value*octave(chan[c.chan].baseFreq);
+        newFreq=chan[c.chan].baseFreq-c.value;
         if (newFreq<=destFreq) {
           newFreq=destFreq;
           return2=true;
         }
       }
+      // check for octave boundary
       if (!chan[c.chan].portaPause) {
-        if (octave(chan[c.chan].baseFreq)!=octave(newFreq)) {
-          chan[c.chan].portaPause=true;
-          break;
+        if ((newFreq&0x7ff)>1288) {
+          newFreq=((newFreq&0x7ff)>>1)|((newFreq+0x800)&0xf800);
+          /*chan[c.chan].portaPause=true;
+          break;*/
+        }
+        if ((newFreq&0x7ff)<644) {
+          newFreq=(newFreq&0x7ff)<<1|((newFreq-0x800)&0xf800);
+          /*chan[c.chan].portaPause=true;
+          break;*/
         }
       }
       chan[c.chan].baseFreq=newFreq;
@@ -699,7 +665,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       }
       break;
     case DIV_CMD_LEGATO: {
-      chan[c.chan].baseFreq=NOTE_FREQUENCY(c.value);
+      chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
       chan[c.chan].note=c.value;
       chan[c.chan].freqChanged=true;
       break;
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index 34db5a25..ce52c6df 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -93,9 +93,6 @@ class DivPlatformGenesis: public DivDispatch {
     short oldWrites[512];
     short pendingWrites[512];
 
-    int octave(int freq);
-    int toFreq(int freq);
-
     friend void putDispatchChan(void*,int,int);
 
     void acquire_nuked(short* bufL, short* bufR, size_t start, size_t len);
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index f0369370..db51f5ea 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -72,7 +72,7 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       opChan[ch].insChanged=false;
 
       if (c.value!=DIV_NOTE_NULL) {
-        opChan[ch].baseFreq=NOTE_FREQUENCY(c.value);
+        opChan[ch].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
         opChan[ch].portaPause=false;
         opChan[ch].freqChanged=true;
       }
@@ -127,31 +127,46 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       break;
     }
     case DIV_CMD_NOTE_PORTA: {
-      int destFreq=NOTE_FREQUENCY(c.value2);
+      int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
       int newFreq;
       bool return2=false;
       if (destFreq>opChan[ch].baseFreq) {
-        newFreq=opChan[ch].baseFreq+c.value*octave(opChan[ch].baseFreq);
+        newFreq=opChan[ch].baseFreq+c.value;
         if (newFreq>=destFreq) {
           newFreq=destFreq;
           return2=true;
         }
       } else {
-        newFreq=opChan[ch].baseFreq-c.value*octave(opChan[ch].baseFreq);
+        newFreq=opChan[ch].baseFreq-c.value;
         if (newFreq<=destFreq) {
           newFreq=destFreq;
           return2=true;
         }
       }
       if (!opChan[ch].portaPause) {
-        if (octave(opChan[ch].baseFreq)!=octave(newFreq)) {
+        opChan[ch].freqChanged=true;
+        if ((newFreq&0x7ff)>1288) {
+          newFreq=((newFreq&0x7ff)>>1)|((newFreq+0x800)&0xf800);
           opChan[ch].portaPause=true;
-          break;
+          opChan[ch].freqChanged=false;
+          return2=false;
+          if (ch==3) printf("%d: upper bound\n",ch);
+          //break;
         }
+        if ((newFreq&0x7ff)<644) {
+          newFreq=(newFreq&0x7ff)<<1|((newFreq-0x800)&0xf800);
+          opChan[ch].portaPause=true;
+          opChan[ch].freqChanged=false;
+          return2=false;
+          if (ch==3) printf("%d: lower bound\n",ch);
+          //break;
+        }
+      } else {
+        opChan[ch].portaPause=false;
+        opChan[ch].freqChanged=true;
       }
+      if (ch==3) printf("%d: writing %.4x to freq\n",ch,newFreq);
       opChan[ch].baseFreq=newFreq;
-      opChan[ch].portaPause=false;
-      opChan[ch].freqChanged=true;
       if (return2) return 2;
       break;
     }
@@ -172,7 +187,7 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       }
       break;
     case DIV_CMD_LEGATO: {
-      opChan[ch].baseFreq=NOTE_FREQUENCY(c.value);
+      opChan[ch].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
       opChan[ch].freqChanged=true;
       break;
     }
@@ -289,35 +304,10 @@ void DivPlatformGenesisExt::tick(bool sysTick) {
   unsigned char writeMask=2;
   if (extMode) for (int i=0; i<4; i++) {
     if (opChan[i].freqChanged) {
-      opChan[i].freq=parent->calcFreq(opChan[i].baseFreq,opChan[i].pitch);
-      if (opChan[i].freq>262143) opChan[i].freq=262143;
-      if (opChan[i].freq>=82432) {
-        opChan[i].freqH=((opChan[i].freq>>15)&7)|0x38;
-        opChan[i].freqL=(opChan[i].freq>>7)&0xff;
-      } else if (opChan[i].freq>=41216) {
-        opChan[i].freqH=((opChan[i].freq>>14)&7)|0x30;
-        opChan[i].freqL=(opChan[i].freq>>6)&0xff;
-      } else if (opChan[i].freq>=20608) {
-        opChan[i].freqH=((opChan[i].freq>>13)&7)|0x28;
-        opChan[i].freqL=(opChan[i].freq>>5)&0xff;
-      } else if (opChan[i].freq>=10304) {
-        opChan[i].freqH=((opChan[i].freq>>12)&7)|0x20;
-        opChan[i].freqL=(opChan[i].freq>>4)&0xff;
-      } else if (opChan[i].freq>=5152) {
-        opChan[i].freqH=((opChan[i].freq>>11)&7)|0x18;
-        opChan[i].freqL=(opChan[i].freq>>3)&0xff;
-      } else if (opChan[i].freq>=2576) {
-        opChan[i].freqH=((opChan[i].freq>>10)&7)|0x10;
-        opChan[i].freqL=(opChan[i].freq>>2)&0xff;
-      } else if (opChan[i].freq>=1288) {
-        opChan[i].freqH=((opChan[i].freq>>9)&7)|0x08;
-        opChan[i].freqL=(opChan[i].freq>>1)&0xff;
-      } else {
-        opChan[i].freqH=(opChan[i].freq>>8)&7;
-        opChan[i].freqL=opChan[i].freq&0xff;
-      }
-      immWrite(opChanOffsH[i],opChan[i].freqH);
-      immWrite(opChanOffsL[i],opChan[i].freqL);
+      opChan[i].freq=(opChan[i].baseFreq&0xf800)|parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch);
+      if (chan[i].freq>65535) chan[i].freq=65535;
+      immWrite(opChanOffsH[i],opChan[i].freq>>8);
+      immWrite(opChanOffsL[i],opChan[i].freq&0xff);
     }
     writeMask|=opChan[i].active<<(4+i);
     if (opChan[i].keyOn) {

From 943e013cb469319fbbda2cc9540e39677ba773d7 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Fri, 22 Apr 2022 16:46:24 -0500
Subject: [PATCH 02/46] YM2612: new pitch slide formula

finally nailed it (almost)
---
 src/engine/platform/genesis.cpp    | 21 +++++++++++++--------
 src/engine/platform/genesisext.cpp | 10 +++-------
 2 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 80dac1d4..615747dc 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -632,21 +632,26 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
         }
       }
       // check for octave boundary
+      // what the heck!
       if (!chan[c.chan].portaPause) {
+        chan[c.chan].freqChanged=true;
         if ((newFreq&0x7ff)>1288) {
-          newFreq=((newFreq&0x7ff)>>1)|((newFreq+0x800)&0xf800);
-          /*chan[c.chan].portaPause=true;
-          break;*/
+          newFreq=(644)|((newFreq+0x800)&0xf800);
+          chan[c.chan].portaPause=true;
+          chan[c.chan].freqChanged=false;
+          return2=false;
         }
         if ((newFreq&0x7ff)<644) {
-          newFreq=(newFreq&0x7ff)<<1|((newFreq-0x800)&0xf800);
-          /*chan[c.chan].portaPause=true;
-          break;*/
+          newFreq=(1287)|((newFreq-0x800)&0xf800);
+          chan[c.chan].portaPause=true;
+          chan[c.chan].freqChanged=false;
+          return2=false;
         }
+      } else {
+        chan[c.chan].portaPause=false;
+        chan[c.chan].freqChanged=true;
       }
       chan[c.chan].baseFreq=newFreq;
-      chan[c.chan].portaPause=false;
-      chan[c.chan].freqChanged=true;
       if (return2) {
         chan[c.chan].inPorta=false;
         return 2;
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index db51f5ea..2f8fba8c 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -143,29 +143,25 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
           return2=true;
         }
       }
+      // what the heck!
       if (!opChan[ch].portaPause) {
         opChan[ch].freqChanged=true;
         if ((newFreq&0x7ff)>1288) {
-          newFreq=((newFreq&0x7ff)>>1)|((newFreq+0x800)&0xf800);
+          newFreq=(644)|((newFreq+0x800)&0xf800);
           opChan[ch].portaPause=true;
           opChan[ch].freqChanged=false;
           return2=false;
-          if (ch==3) printf("%d: upper bound\n",ch);
-          //break;
         }
         if ((newFreq&0x7ff)<644) {
-          newFreq=(newFreq&0x7ff)<<1|((newFreq-0x800)&0xf800);
+          newFreq=(1287)|((newFreq-0x800)&0xf800);
           opChan[ch].portaPause=true;
           opChan[ch].freqChanged=false;
           return2=false;
-          if (ch==3) printf("%d: lower bound\n",ch);
-          //break;
         }
       } else {
         opChan[ch].portaPause=false;
         opChan[ch].freqChanged=true;
       }
-      if (ch==3) printf("%d: writing %.4x to freq\n",ch,newFreq);
       opChan[ch].baseFreq=newFreq;
       if (return2) return 2;
       break;

From dd80cb8b55c9adf7e7c2441cf4ca47105300d7d6 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Fri, 22 Apr 2022 17:42:42 -0500
Subject: [PATCH 03/46] what the heck

---
 src/engine/platform/genesis.cpp    | 2 +-
 src/engine/platform/genesisext.cpp | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 615747dc..43aae3f1 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -394,7 +394,7 @@ void DivPlatformGenesis::tick(bool sysTick) {
   for (int i=0; i<6; i++) {
     if (i==2 && extMode) continue;
     if (chan[i].freqChanged) {
-      chan[i].freq=((chan[i].baseFreq&0xf800)|parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false))+chan[i].std.pitch.val;
+      chan[i].freq=((chan[i].baseFreq&0xf800)|parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false,4))+chan[i].std.pitch.val;
       if (chan[i].freq>65535) chan[i].freq=65535;
       int freqt=chan[i].freq;
       immWrite(chanOffs[i]+ADDR_FREQH,freqt>>8);
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index 2f8fba8c..bb33f401 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -300,7 +300,7 @@ void DivPlatformGenesisExt::tick(bool sysTick) {
   unsigned char writeMask=2;
   if (extMode) for (int i=0; i<4; i++) {
     if (opChan[i].freqChanged) {
-      opChan[i].freq=(opChan[i].baseFreq&0xf800)|parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch);
+      opChan[i].freq=(opChan[i].baseFreq&0xf800)|parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch,false,4);
       if (chan[i].freq>65535) chan[i].freq=65535;
       immWrite(opChanOffsH[i],opChan[i].freq>>8);
       immWrite(opChanOffsL[i],opChan[i].freq&0xff);

From f6b34a5bb0535383385b3da4014c4bfc5da58eed Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 23 Apr 2022 04:25:22 -0500
Subject: [PATCH 04/46] huh?

---
 src/engine/platform/genesisext.cpp | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index bb33f401..d8ae8b38 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -144,19 +144,18 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
         }
       }
       // what the heck!
+      // TODO: rework!
       if (!opChan[ch].portaPause) {
-        opChan[ch].freqChanged=true;
         if ((newFreq&0x7ff)>1288) {
           newFreq=(644)|((newFreq+0x800)&0xf800);
           opChan[ch].portaPause=true;
-          opChan[ch].freqChanged=false;
           return2=false;
-        }
-        if ((newFreq&0x7ff)<644) {
+        } else if ((newFreq&0x7ff)<644) {
           newFreq=(1287)|((newFreq-0x800)&0xf800);
           opChan[ch].portaPause=true;
-          opChan[ch].freqChanged=false;
           return2=false;
+        } else {
+          opChan[ch].freqChanged=true;
         }
       } else {
         opChan[ch].portaPause=false;

From f716ac262d87a96676c07c20845d2e603b13be0e Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sat, 23 Apr 2022 19:52:09 +1000
Subject: [PATCH 05/46] #79: OPM import progress and start everything else

---
 src/engine/engine.h       |   7 ++
 src/engine/fileOpsIns.cpp | 150 ++++++++++++++++++++++++++++++++++++--
 src/engine/safeReader.cpp |  48 +++++++++++-
 src/engine/safeReader.h   |   3 +
 4 files changed, 198 insertions(+), 10 deletions(-)

diff --git a/src/engine/engine.h b/src/engine/engine.h
index 515b9c59..c8afb86a 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -31,6 +31,7 @@
 #include <mutex>
 #include <map>
 #include <queue>
+#include <sstream>
 
 #define addWarning(x) \
   if (warnings.empty()) { \
@@ -288,9 +289,15 @@ class DivEngine {
   void loadVGI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadS3I(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadPAT(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadFF(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadWOPL(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
+  void loadWOPN(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
 
   bool initAudioBackend();
   bool deinitAudioBackend();
diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index f9eaab38..148c9d2e 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -30,9 +30,15 @@ enum DivInsFormats {
   DIV_INSFORMAT_BTI,
   DIV_INSFORMAT_S3I,
   DIV_INSFORMAT_SBI,
+  DIV_INSFORMAT_PAT,
+  DIV_INSFORMAT_Y12,
+  DIV_INSFORMAT_OPLI,
+  DIV_INSFORMAT_OPNI,
   DIV_INSFORMAT_BNK,
   DIV_INSFORMAT_OPM,
   DIV_INSFORMAT_FF,
+  DIV_INSFORMAT_WOPL,
+  DIV_INSFORMAT_WOPN,
 };
 
 // Patch data structures
@@ -670,6 +676,7 @@ void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, St
         auto& ins = insList[i];
 
         ins->type = DIV_INS_OPL;
+        ins->fm.ops = 2;
 
         timbre.mode = reader.readC();
         timbre.percVoice = reader.readC();
@@ -810,16 +817,132 @@ void DivEngine::loadFF(SafeReader& reader, std::vector<DivInstrument*>& ret, Str
 }
 
 void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
-  DivInstrument* ins[128];
-  memset(ins,0,128*sizeof(void*));
+  std::vector<DivInstrument*> insList;
+  std::stringstream ss;
+
+  int readCount = 0;
+
+  bool patchNameRead = false,
+       lfoRead = false,
+       characteristicRead = false,
+       m1Read = false,
+       c1Read = false,
+       m2Read = false,
+       c2Read = false;
+  
+  auto completePatchRead = [&]() {
+    return patchNameRead && lfoRead && characteristicRead && m1Read && c1Read && m2Read && c2Read;
+  };
+  auto resetPatchRead = [&]() {
+    patchNameRead = lfoRead = characteristicRead = m1Read = c1Read = m2Read = c2Read = false;
+  };
+  auto readOpmOperator = [](SafeReader& reader, DivInstrumentFM::Operator& op) {
+    op.ar = atoi(reader.readString_Token().c_str());
+    op.dr = atoi(reader.readString_Token().c_str());
+    op.d2r = atoi(reader.readString_Token().c_str());
+    op.rr = atoi(reader.readString_Token().c_str());
+    op.sl = atoi(reader.readString_Token().c_str());
+    op.tl = atoi(reader.readString_Token().c_str());
+    op.ksl = atoi(reader.readString_Token().c_str());
+    op.mult = atoi(reader.readString_Token().c_str());
+    op.dt = atoi(reader.readString_Token().c_str());
+    op.dt2 = atoi(reader.readString_Token().c_str());
+    op.ssgEnv = atoi(reader.readString_Token().c_str());
+  };
+
+  DivInstrument* newPatch = nullptr;
 
   try {
-    String line;
-        
+    reader.seek(0, SEEK_SET);
+    while (!reader.isEOF()) {
+      String token = reader.readString_Token();
+      if (token.length() == 0) {
+        continue;
+      }
+
+      if (token.compare(0,2,"//") == 0) {
+        if (!reader.isEOF()) {
+          reader.readString_Line();
+        }
+        continue;
+      }
+
+      // At this point we know any other line would be associated with patch params
+      if (newPatch == nullptr) {
+        newPatch = new DivInstrument;
+        newPatch->type = DIV_INS_FM;
+        newPatch->fm.ops = 4;
+      }
+
+      // Read each line for their respective params. They may not be written in the same order but they 
+      // must absolutely be properly grouped per patch! Line prefixes must be separated by a space!
+      
+      // Patch number + name
+      // "@:123 Name of patch"
+      if (token.length() >= 2) {
+        if (token[0] == '@') {
+          newPatch->name = reader.readString_Line();
+          patchNameRead = true;
+        } else if (token.compare(0,3,"CH:") == 0) {
+          // CH: PAN FL CON AMS PMS SLOT NE
+          reader.readString_Token(); // skip PAN
+          newPatch->fm.fb = atoi(reader.readString_Token().c_str());
+          newPatch->fm.alg = atoi(reader.readString_Token().c_str());
+          newPatch->fm.ams = atoi(reader.readString_Token().c_str());
+          newPatch->fm.ams2 = atoi(reader.readString_Token().c_str());
+          reader.readString_Token(); // skip SLOT
+          reader.readString_Token(); // skip NE
+          characteristicRead = true;
+        } else if (token.compare(0,3,"C1:") == 0) {
+          // C1: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
+          readOpmOperator(reader, newPatch->fm.op[2]);
+          c1Read = true;
+        } else if (token.compare(0,3,"C2:") == 0) {
+          // C2: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
+          readOpmOperator(reader, newPatch->fm.op[3]);
+          c2Read = true;
+        } else if (token.compare(0,3,"M1:") == 0) {
+          // M1: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
+          readOpmOperator(reader, newPatch->fm.op[0]);
+          m1Read = true;
+        } else if (token.compare(0,3,"M2:") == 0) {
+          // M2: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
+          readOpmOperator(reader, newPatch->fm.op[1]);
+          m2Read = true;
+        } else if (token.compare(0,4,"LFO:") == 0) {
+          // LFO: LFRQ AMD PMD WF NFRQ
+          // Furnace patches do not store this as these are chip-global.
+          reader.readString_Line();
+          lfoRead = true;
+        } else {
+          // other unsupported lines ignored.
+          reader.readString_Line();
+        }
+      }
+
+      if (completePatchRead()) {
+        insList.push_back(newPatch);
+        newPatch = nullptr;
+        ++readCount;
+      }
+    }
+
+    if (newPatch != nullptr) {
+      addWarning("Last OPM patch read was incomplete and therefore not imported.");
+      logW("Last OPM patch read was incomplete and therefore not imported.");
+      delete newPatch;
+    }
+
+    for (int i = 0; i < readCount; ++i) {
+      ret.push_back(insList[i]);
+    }
   } catch (EndOfFileException& e) {
-    lastError="premature end of file";
+    lastError = "premature end of file";
     logE("premature end of file");
-    return;
+    for (int i = readCount; i >= 0; --i) {
+      delete insList[i];
+    }
+    delete newPatch;
   }
 }
 
@@ -947,12 +1070,24 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
         format=DIV_INSFORMAT_S3I;
       } else if (extS==String(".sbi")) {
         format=DIV_INSFORMAT_SBI;
+      } else if (extS==String(".opli")) {
+        format=DIV_INSFORMAT_OPLI;
+      } else if (extS==String(".opni")) {
+        format=DIV_INSFORMAT_OPNI;
+      } else if (extS==String(".pat")) {
+        format=DIV_INSFORMAT_PAT;
+      } else if (extS==String(".y12")) {
+        format=DIV_INSFORMAT_Y12;
       } else if (extS==String(".bnk")) {
         format=DIV_INSFORMAT_BNK;
       } else if (extS==String(".opm")) {
         format=DIV_INSFORMAT_OPM;
       } else if (extS==String(".ff")) {
         format=DIV_INSFORMAT_FF;
+      } else if (extS==String(".wopl")) {
+        format=DIV_INSFORMAT_WOPL;
+      } else if (extS==String(".wopn")) {
+        format=DIV_INSFORMAT_WOPN;
       }
     }
 
@@ -971,7 +1106,8 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
         break;
       case DIV_INSFORMAT_BTI: // TODO
         break;
-      case DIV_INSFORMAT_OPM: // TODO
+      case DIV_INSFORMAT_OPM:
+        loadOPM(reader,ret,stripPath);
         break;
       case DIV_INSFORMAT_S3I:
         loadS3I(reader,ret,stripPath);
diff --git a/src/engine/safeReader.cpp b/src/engine/safeReader.cpp
index 7fa66e8b..e46827c6 100644
--- a/src/engine/safeReader.cpp
+++ b/src/engine/safeReader.cpp
@@ -139,12 +139,14 @@ double SafeReader::readD() {
 }
 
 String SafeReader::readString(size_t stlen) {
-  String ret;
+  String ret(stlen, ' ');
 #ifdef READ_DEBUG
   logD("SR: reading string len %d at %x",stlen,curSeek);
 #endif
   size_t curPos=0;
-  while (curPos<stlen) {
+  if (isEOF()) throw EndOfFileException(this, len);
+
+  while (!isEOF() && curPos<stlen) {
     unsigned char c=readC();
     if (c!=0) ret.push_back(c);
     curPos++;
@@ -155,8 +157,48 @@ String SafeReader::readString(size_t stlen) {
 String SafeReader::readString() {
   String ret;
   unsigned char c;
-  while ((c=readC())!=0) {
+  if (isEOF()) throw EndOfFileException(this, len);
+
+  while (!isEOF() && (c=readC())!=0) {
     ret.push_back(c);
   }
   return ret;
 }
+
+String SafeReader::readString_Line() {
+  String ret;
+  unsigned char c;
+  if (isEOF()) throw EndOfFileException(this, len);
+
+  while (!isEOF() && (c = readC()) != 0) {
+    if (c=='\r'||c=='\n') {
+      break;
+    }
+    ret.push_back(c);
+  }
+  return ret;
+}
+
+String SafeReader::readString_Token(unsigned char delim) {
+  String ret;
+  unsigned char c;
+  if (isEOF()) throw EndOfFileException(this, len);
+
+  while (!isEOF() && (c=readC())!=0) {
+    if (c == '\r' || c == '\n') {
+      break;
+    }
+    if (c == delim) {
+      if (ret.length() == 0) {
+        continue;
+      }
+      break;
+    }
+    ret.push_back(c);
+  }
+  return ret;
+}
+
+bool SafeReader::isEOF() {
+  return curSeek >= len;
+}
\ No newline at end of file
diff --git a/src/engine/safeReader.h b/src/engine/safeReader.h
index f674f592..9fd0282b 100644
--- a/src/engine/safeReader.h
+++ b/src/engine/safeReader.h
@@ -66,6 +66,9 @@ class SafeReader {
     double readD_BE();
     String readString();
     String readString(size_t len);
+    String readString_Line();
+    String readString_Token(unsigned char delim=' ');
+    bool isEOF();
 
     SafeReader(void* b, size_t l):
       buf((unsigned char*)b),

From 3550ad512a83bdd1c420056838905098fdd3a2fa Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sat, 23 Apr 2022 20:20:29 +1000
Subject: [PATCH 06/46] OPM import: Fix reset read procedural flow

---
 src/engine/fileOpsIns.cpp | 7 ++++---
 src/gui/gui.cpp           | 4 ++--
 src/gui/settings.cpp      | 1 +
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index 148c9d2e..b74c7cba 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -829,12 +829,15 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
        c1Read = false,
        m2Read = false,
        c2Read = false;
+
+  DivInstrument* newPatch = nullptr;
   
   auto completePatchRead = [&]() {
     return patchNameRead && lfoRead && characteristicRead && m1Read && c1Read && m2Read && c2Read;
   };
   auto resetPatchRead = [&]() {
     patchNameRead = lfoRead = characteristicRead = m1Read = c1Read = m2Read = c2Read = false;
+    newPatch = nullptr;
   };
   auto readOpmOperator = [](SafeReader& reader, DivInstrumentFM::Operator& op) {
     op.ar = atoi(reader.readString_Token().c_str());
@@ -850,8 +853,6 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     op.ssgEnv = atoi(reader.readString_Token().c_str());
   };
 
-  DivInstrument* newPatch = nullptr;
-
   try {
     reader.seek(0, SEEK_SET);
     while (!reader.isEOF()) {
@@ -922,7 +923,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
 
       if (completePatchRead()) {
         insList.push_back(newPatch);
-        newPatch = nullptr;
+        resetPatchRead();
         ++readCount;
       }
     }
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 009952a6..d3218b30 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -1290,9 +1290,9 @@ void FurnaceGUI::openFileDialog(FurnaceGUIFileDialogs type) {
       if (!dirExists(workingDirIns)) workingDirIns=getHomeDir();
       hasOpened=fileDialog->openLoad(
         "Load Instrument",
-        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.bnk *.ff",
+        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.bnk *.ff *.opm",
          "all files", ".*"},
-        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.bnk,.ff},.*",
+        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.bnk,.ff,.opm},.*",
         workingDirIns,
         dpiScale
       );
diff --git a/src/gui/settings.cpp b/src/gui/settings.cpp
index f1cd27a3..f1565b8e 100644
--- a/src/gui/settings.cpp
+++ b/src/gui/settings.cpp
@@ -2489,6 +2489,7 @@ void FurnaceGUI::applyUISettings(bool updateFonts) {
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".fti",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".bti",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".ff",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
+  ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".opm",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
 
   if (updateFonts) {
     if (fileDialog!=NULL) delete fileDialog;

From 8ad827478c20cd7858cb77f797231b802babf665 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sat, 23 Apr 2022 21:48:18 +1000
Subject: [PATCH 07/46] #79: OPM complete for now

---
 src/engine/fileOpsIns.cpp | 47 ++++++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 20 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index b74c7cba..a8b2b652 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -839,18 +839,23 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     patchNameRead = lfoRead = characteristicRead = m1Read = c1Read = m2Read = c2Read = false;
     newPatch = nullptr;
   };
-  auto readOpmOperator = [](SafeReader& reader, DivInstrumentFM::Operator& op) {
-    op.ar = atoi(reader.readString_Token().c_str());
-    op.dr = atoi(reader.readString_Token().c_str());
-    op.d2r = atoi(reader.readString_Token().c_str());
-    op.rr = atoi(reader.readString_Token().c_str());
-    op.sl = atoi(reader.readString_Token().c_str());
-    op.tl = atoi(reader.readString_Token().c_str());
-    op.ksl = atoi(reader.readString_Token().c_str());
-    op.mult = atoi(reader.readString_Token().c_str());
-    op.dt = atoi(reader.readString_Token().c_str());
-    op.dt2 = atoi(reader.readString_Token().c_str());
-    op.ssgEnv = atoi(reader.readString_Token().c_str());
+  auto readIntStrWithinRange = [](String& input, int limitLow, int limitHigh) {
+    int x = atoi(input.c_str());
+    return (x>limitHigh) ? limitHigh :
+           (x<limitLow) ? limitLow : x;
+  };
+  auto readOpmOperator = [readIntStrWithinRange](SafeReader& reader, DivInstrumentFM::Operator& op) {
+    op.ar = readIntStrWithinRange(reader.readString_Token(), 0, 31);
+    op.dr = readIntStrWithinRange(reader.readString_Token(), 0, 31);
+    op.d2r = readIntStrWithinRange(reader.readString_Token(), 0, 31);
+    op.rr = readIntStrWithinRange(reader.readString_Token(), 0, 31);
+    op.sl = readIntStrWithinRange(reader.readString_Token(), 0, 15);
+    op.tl = readIntStrWithinRange(reader.readString_Token(), 0, 127);
+    op.rs = readIntStrWithinRange(reader.readString_Token(), 0, 3);;
+    op.mult = readIntStrWithinRange(reader.readString_Token(), 0, 15);
+    op.dt = readIntStrWithinRange(reader.readString_Token(), -3, 4);
+    op.dt2 = readIntStrWithinRange(reader.readString_Token(), 0, 3);
+    op.am = readIntStrWithinRange(reader.readString_Token(), 0, 1);
   };
 
   try {
@@ -875,22 +880,24 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
         newPatch->fm.ops = 4;
       }
 
-      // Read each line for their respective params. They may not be written in the same order but they 
+      // Read each line for their respective params. They may not be written in the same LINE order but they 
       // must absolutely be properly grouped per patch! Line prefixes must be separated by a space!
       
-      // Patch number + name
-      // "@:123 Name of patch"
       if (token.length() >= 2) {
         if (token[0] == '@') {
+          // @:123 Name of patch
+          // Note: Fallback to bank filename and current patch number in _file_ order (not @n order)
           newPatch->name = reader.readString_Line();
+          newPatch->name = newPatch->name.length() > 0 ? newPatch->name : fmt::format("{0}[{1}]", stripPath, readCount);
+          
           patchNameRead = true;
         } else if (token.compare(0,3,"CH:") == 0) {
           // CH: PAN FL CON AMS PMS SLOT NE
           reader.readString_Token(); // skip PAN
-          newPatch->fm.fb = atoi(reader.readString_Token().c_str());
-          newPatch->fm.alg = atoi(reader.readString_Token().c_str());
-          newPatch->fm.ams = atoi(reader.readString_Token().c_str());
-          newPatch->fm.ams2 = atoi(reader.readString_Token().c_str());
+          newPatch->fm.fb = readIntStrWithinRange(reader.readString_Token(), 0, 7);
+          newPatch->fm.alg = readIntStrWithinRange(reader.readString_Token(), 0, 7);
+          newPatch->fm.ams = readIntStrWithinRange(reader.readString_Token(), 0, 4);
+          newPatch->fm.fms = readIntStrWithinRange(reader.readString_Token(), 0, 7);
           reader.readString_Token(); // skip SLOT
           reader.readString_Token(); // skip NE
           characteristicRead = true;
@@ -912,7 +919,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
           m2Read = true;
         } else if (token.compare(0,4,"LFO:") == 0) {
           // LFO: LFRQ AMD PMD WF NFRQ
-          // Furnace patches do not store this as these are chip-global.
+          // Furnace patches do not store these as these are chip-global.
           reader.readString_Line();
           lfoRead = true;
         } else {

From 0f47a3ed7b049208183a6f84067b4a53898e3f47 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sat, 23 Apr 2022 23:40:58 +1000
Subject: [PATCH 08/46] Fix DT range

---
 src/engine/fileOpsIns.cpp | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index a8b2b652..8b43f65e 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -640,6 +640,7 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     delete ins;
   }
 }
+
 void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
   std::vector<DivInstrument*> insList;
   std::vector<String*> instNames;
@@ -853,7 +854,8 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     op.tl = readIntStrWithinRange(reader.readString_Token(), 0, 127);
     op.rs = readIntStrWithinRange(reader.readString_Token(), 0, 3);;
     op.mult = readIntStrWithinRange(reader.readString_Token(), 0, 15);
-    op.dt = readIntStrWithinRange(reader.readString_Token(), -3, 4);
+    op.dt = readIntStrWithinRange(reader.readString_Token(), 0, 7);
+    op.dt = (op.dt >= 4) ? (7 - op.dt) : (op.dt + 3);
     op.dt2 = readIntStrWithinRange(reader.readString_Token(), 0, 3);
     op.am = readIntStrWithinRange(reader.readString_Token(), 0, 1);
   };
@@ -881,7 +883,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       }
 
       // Read each line for their respective params. They may not be written in the same LINE order but they 
-      // must absolutely be properly grouped per patch! Line prefixes must be separated by a space!
+      // must absolutely be properly grouped per patch! Line prefixes must be separated by a space! (see inline comments)
       
       if (token.length() >= 2) {
         if (token[0] == '@') {
@@ -889,8 +891,8 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
           // Note: Fallback to bank filename and current patch number in _file_ order (not @n order)
           newPatch->name = reader.readString_Line();
           newPatch->name = newPatch->name.length() > 0 ? newPatch->name : fmt::format("{0}[{1}]", stripPath, readCount);
-          
           patchNameRead = true;
+
         } else if (token.compare(0,3,"CH:") == 0) {
           // CH: PAN FL CON AMS PMS SLOT NE
           reader.readString_Token(); // skip PAN
@@ -901,27 +903,33 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
           reader.readString_Token(); // skip SLOT
           reader.readString_Token(); // skip NE
           characteristicRead = true;
+
         } else if (token.compare(0,3,"C1:") == 0) {
           // C1: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
           readOpmOperator(reader, newPatch->fm.op[2]);
           c1Read = true;
+
         } else if (token.compare(0,3,"C2:") == 0) {
           // C2: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
           readOpmOperator(reader, newPatch->fm.op[3]);
           c2Read = true;
+
         } else if (token.compare(0,3,"M1:") == 0) {
           // M1: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
           readOpmOperator(reader, newPatch->fm.op[0]);
           m1Read = true;
+
         } else if (token.compare(0,3,"M2:") == 0) {
           // M2: AR D1R D2R RR D1L TL KS MUL DT1 DT2 AMS-EN
           readOpmOperator(reader, newPatch->fm.op[1]);
           m2Read = true;
+
         } else if (token.compare(0,4,"LFO:") == 0) {
           // LFO: LFRQ AMD PMD WF NFRQ
-          // Furnace patches do not store these as these are chip-global.
+          // Furnace patches do not store these as they are chip-global.
           reader.readString_Line();
           lfoRead = true;
+
         } else {
           // other unsupported lines ignored.
           reader.readString_Line();
@@ -950,7 +958,9 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     for (int i = readCount; i >= 0; --i) {
       delete insList[i];
     }
-    delete newPatch;
+    if (newPatch != nullptr) {
+      delete newPatch;
+    }
   }
 }
 

From b8d9fab7455963f675f10ce223ad665a07841066 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 00:29:33 +1000
Subject: [PATCH 09/46] Start .y12 (Gens KMod/Kaneda) patch dump import

---
 src/engine/fileOpsIns.cpp | 48 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 45 insertions(+), 3 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index 8b43f65e..ddf9a1df 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -641,6 +641,45 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
   }
 }
 
+void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {  
+  DivInstrument *ins = new DivInstrument;
+
+  try {
+    reader.seek(0, SEEK_SET);
+    ins->type = DIV_INS_FM;
+    ins->fm.ops = 4;
+    ins->name = stripPath;
+
+    for (int i = 0; i < 4; ++i) {
+      DivInstrumentFM::Operator& insOp = ins->fm.op[i];
+      uint8_t tmp = reader.readC();
+      insOp.mult = (tmp & 0xF);
+      insOp.dt = ((tmp >> 4) & 0x7);
+      insOp.tl = (reader.readC() & 0xF);
+      tmp = reader.readC();
+      insOp.rs = ((tmp >> 6) & 0x3);
+      insOp.ar = (tmp & 0x1F);
+      tmp = reader.readC();
+      insOp.dr = (tmp & 0x1F);
+      insOp.am = ((tmp >> 7) & 0x1);
+      insOp.d2r = (reader.readC() & 0x1F);
+      tmp = reader.readC();
+      insOp.rr = (tmp & 0xF);
+      insOp.sl = ((tmp >> 4) & 0xF);
+      insOp.ssgEnv = reader.readC();
+      reader.seek(9, SEEK_CUR);
+    }
+    ins->fm.alg = reader.readC();
+    ins->fm.fb = reader.readC();
+    reader.seek(14, SEEK_CUR);
+    ret.push_back(ins);
+  } catch (EndOfFileException& e) {
+    lastError = "premature end of file";
+    logE("premature end of file");
+    delete ins;
+  }
+}
+
 void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
   std::vector<DivInstrument*> insList;
   std::vector<String*> instNames;
@@ -1124,21 +1163,24 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
         break;
       case DIV_INSFORMAT_BTI: // TODO
         break;
-      case DIV_INSFORMAT_OPM:
-        loadOPM(reader,ret,stripPath);
-        break;
       case DIV_INSFORMAT_S3I:
         loadS3I(reader,ret,stripPath);
         break;
       case DIV_INSFORMAT_SBI:
         loadSBI(reader,ret,stripPath);
         break;
+      case DIV_INSFORMAT_Y12:
+        loadY12(reader,ret,stripPath);
+        break;
       case DIV_INSFORMAT_BNK:
         loadBNK(reader, ret, stripPath);
         break;
       case DIV_INSFORMAT_FF:
         loadFF(reader,ret,stripPath);
         break;
+      case DIV_INSFORMAT_OPM:
+        loadOPM(reader, ret, stripPath);
+        break;
     }
 
     if (reader.tell()<reader.size()) {

From a049e43618abd65e17c56d3d143d75bb342058a4 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 00:45:19 +1000
Subject: [PATCH 10/46] #79: .y12 import done

---
 src/engine/fileOpsIns.cpp | 6 +++---
 src/gui/gui.cpp           | 4 ++--
 src/gui/settings.cpp      | 1 +
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index ddf9a1df..602fbba5 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -650,12 +650,12 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     ins->fm.ops = 4;
     ins->name = stripPath;
 
-    for (int i = 0; i < 4; ++i) {
+    for (int i : {0,1,2,3}) {
       DivInstrumentFM::Operator& insOp = ins->fm.op[i];
       uint8_t tmp = reader.readC();
       insOp.mult = (tmp & 0xF);
       insOp.dt = ((tmp >> 4) & 0x7);
-      insOp.tl = (reader.readC() & 0xF);
+      insOp.tl = (reader.readC() & 0x3F);
       tmp = reader.readC();
       insOp.rs = ((tmp >> 6) & 0x3);
       insOp.ar = (tmp & 0x1F);
@@ -671,7 +671,7 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     }
     ins->fm.alg = reader.readC();
     ins->fm.fb = reader.readC();
-    reader.seek(14, SEEK_CUR);
+    reader.seek(62, SEEK_CUR);
     ret.push_back(ins);
   } catch (EndOfFileException& e) {
     lastError = "premature end of file";
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index d3218b30..47b81f6e 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -1290,9 +1290,9 @@ void FurnaceGUI::openFileDialog(FurnaceGUIFileDialogs type) {
       if (!dirExists(workingDirIns)) workingDirIns=getHomeDir();
       hasOpened=fileDialog->openLoad(
         "Load Instrument",
-        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.bnk *.ff *.opm",
+        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.y12 *.bnk *.ff *.opm",
          "all files", ".*"},
-        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.bnk,.ff,.opm},.*",
+        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.y12,.bnk,.ff,.opm},.*",
         workingDirIns,
         dpiScale
       );
diff --git a/src/gui/settings.cpp b/src/gui/settings.cpp
index f1565b8e..5ed9cf0a 100644
--- a/src/gui/settings.cpp
+++ b/src/gui/settings.cpp
@@ -2485,6 +2485,7 @@ void FurnaceGUI::applyUISettings(bool updateFonts) {
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".vgi",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".s3i",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".sbi",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
+  ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".y12",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".bnk",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".fti",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".bti",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);

From 6bd199923f042bb1d9882fec6869eab7bf2112ae Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 02:37:25 +1000
Subject: [PATCH 11/46] OPLI progress... still figuring out correct readings

---
 src/engine/engine.h       |   3 -
 src/engine/fileOpsIns.cpp | 126 +++++++++++++++++++++++++++++++++-----
 src/engine/safeReader.cpp |   2 +-
 src/gui/settings.cpp      |   2 +
 4 files changed, 114 insertions(+), 19 deletions(-)

diff --git a/src/engine/engine.h b/src/engine/engine.h
index c8afb86a..5e840362 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -291,13 +291,10 @@ class DivEngine {
   void loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
-  void loadPAT(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
   void loadFF(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
-  void loadWOPL(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
-  void loadWOPN(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath);
 
   bool initAudioBackend();
   bool deinitAudioBackend();
diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index 602fbba5..87233ef6 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -30,15 +30,12 @@ enum DivInsFormats {
   DIV_INSFORMAT_BTI,
   DIV_INSFORMAT_S3I,
   DIV_INSFORMAT_SBI,
-  DIV_INSFORMAT_PAT,
   DIV_INSFORMAT_Y12,
   DIV_INSFORMAT_OPLI,
   DIV_INSFORMAT_OPNI,
   DIV_INSFORMAT_BNK,
   DIV_INSFORMAT_OPM,
   DIV_INSFORMAT_FF,
-  DIV_INSFORMAT_WOPL,
-  DIV_INSFORMAT_WOPN,
 };
 
 // Patch data structures
@@ -641,6 +638,105 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
   }
 }
 
+void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
+  DivInstrument* ins = new DivInstrument;
+
+  try {
+    reader.seek(0, SEEK_SET);
+    String header = reader.readString(11);
+    if (header.compare("WOPL3-INST") == 0) {
+      uint16_t version = reader.readS();
+      bool isPerc = (reader.readC() == 1);
+
+      ins->type = DIV_INS_OPL;
+      String insName = reader.readString(32);
+      insName = (insName.length() > 0) ? insName : stripPath;
+      ins->name = insName;
+      reader.seek(7, SEEK_CUR);  // skip MIDI params
+      uint8_t instTypeFlags = reader.readC();  // [0EEEDCBA] - see WOPL/OPLI spec
+
+      bool is_2op = ((instTypeFlags & 0x1) > 0);
+      bool is_4op = (((instTypeFlags>>1) & 0x1) > 0);
+      bool is_2x2op = (((instTypeFlags>>2) & 0x1) > 0);
+      bool is_rhythm = (((instTypeFlags>>4) & 0x7) > 0);
+
+      auto readOpliOp = [](SafeReader& reader, DivInstrumentFM::Operator op) {
+        uint8_t characteristics = reader.readC();
+        uint8_t keyScaleLevel = reader.readC();
+        uint8_t attackDecay = reader.readC();
+        uint8_t sustainRelease = reader.readC();
+        uint8_t waveSelect = reader.readC();
+
+        op.mult = characteristics & 0xF;
+        op.ksr = ((characteristics >> 4) & 0x1);
+        op.sus = ((characteristics >> 5) & 0x1);
+        op.vib = ((characteristics >> 6) & 0x1);
+        op.am = ((characteristics >> 7) & 0x1);
+        op.tl = keyScaleLevel & 0x3F;
+        op.ksl = ((keyScaleLevel >> 6) & 0x3);
+        op.ar = ((attackDecay >> 4) & 0xF);
+        op.dr = attackDecay & 0xF;
+        op.rr = sustainRelease & 0xF;
+        op.sl = ((sustainRelease >> 4) & 0xF);
+        op.ws = waveSelect;
+      };
+
+      uint8_t feedConnect = reader.readC();
+      uint8_t feedConnect2nd = reader.readC();
+
+      ins->fm.alg = (feedConnect & 0x1);
+      ins->fm.fb = ((feedConnect >> 1) & 0xF);
+
+      if (is_4op) {
+        ins->fm.ops = 4;
+        ins->fm.alg = (feedConnect & 0x1) | ((feedConnect2nd & 0x1) << 1);
+        for (int i : {0,2,1,3}) {
+          readOpliOp(reader, ins->fm.op[i]);
+        }
+      } else {
+        ins->fm.ops = 2;
+        for (int i = 0; i < 2; ++i) {
+          readOpliOp(reader, ins->fm.op[i]);
+        }
+        if (is_rhythm) {
+          ins->fm.opllPreset = (uint8_t)(1<<4);
+
+        } else if (is_2x2op) {
+          ins->name = fmt::format("{0} (1)", insName);
+          ret.push_back(ins);
+
+          ins = new DivInstrument;
+          ins->type = DIV_INS_OPL;
+          ins->name = fmt::format("{0} (2)", insName);
+          for (int i = 0; i < 2; ++i) {
+            readOpliOp(reader, ins->fm.op[i]);
+          }
+        }
+      }
+
+      // Skip rest of file
+      reader.seek(0, SEEK_END);
+      ret.push_back(ins);
+    }
+  } catch (EndOfFileException& e) {
+    lastError = "premature end of file";
+    logE("premature end of file");
+    delete ins;
+  }
+}
+
+void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
+  DivInstrument* ins = new DivInstrument;
+
+  try {
+    reader.seek(0, SEEK_SET);
+  } catch (EndOfFileException& e) {
+    lastError = "premature end of file";
+    logE("premature end of file");
+    delete ins;
+  }
+}
+
 void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {  
   DivInstrument *ins = new DivInstrument;
 
@@ -653,18 +749,18 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     for (int i : {0,1,2,3}) {
       DivInstrumentFM::Operator& insOp = ins->fm.op[i];
       uint8_t tmp = reader.readC();
-      insOp.mult = (tmp & 0xF);
+      insOp.mult = tmp & 0xF;
       insOp.dt = ((tmp >> 4) & 0x7);
       insOp.tl = (reader.readC() & 0x3F);
       tmp = reader.readC();
       insOp.rs = ((tmp >> 6) & 0x3);
-      insOp.ar = (tmp & 0x1F);
+      insOp.ar = tmp & 0x1F;
       tmp = reader.readC();
-      insOp.dr = (tmp & 0x1F);
+      insOp.dr = tmp & 0x1F;
       insOp.am = ((tmp >> 7) & 0x1);
       insOp.d2r = (reader.readC() & 0x1F);
       tmp = reader.readC();
-      insOp.rr = (tmp & 0xF);
+      insOp.rr = tmp & 0xF;
       insOp.sl = ((tmp >> 4) & 0xF);
       insOp.ssgEnv = reader.readC();
       reader.seek(9, SEEK_CUR);
@@ -884,7 +980,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     return (x>limitHigh) ? limitHigh :
            (x<limitLow) ? limitLow : x;
   };
-  auto readOpmOperator = [readIntStrWithinRange](SafeReader& reader, DivInstrumentFM::Operator& op) {
+  auto readOpmOperator = [&](SafeReader& reader, DivInstrumentFM::Operator& op) {
     op.ar = readIntStrWithinRange(reader.readString_Token(), 0, 31);
     op.dr = readIntStrWithinRange(reader.readString_Token(), 0, 31);
     op.d2r = readIntStrWithinRange(reader.readString_Token(), 0, 31);
@@ -1130,9 +1226,7 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
       } else if (extS==String(".opli")) {
         format=DIV_INSFORMAT_OPLI;
       } else if (extS==String(".opni")) {
-        format=DIV_INSFORMAT_OPNI;
-      } else if (extS==String(".pat")) {
-        format=DIV_INSFORMAT_PAT;
+        format=DIV_INSFORMAT_OPNI;;
       } else if (extS==String(".y12")) {
         format=DIV_INSFORMAT_Y12;
       } else if (extS==String(".bnk")) {
@@ -1141,10 +1235,6 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
         format=DIV_INSFORMAT_OPM;
       } else if (extS==String(".ff")) {
         format=DIV_INSFORMAT_FF;
-      } else if (extS==String(".wopl")) {
-        format=DIV_INSFORMAT_WOPL;
-      } else if (extS==String(".wopn")) {
-        format=DIV_INSFORMAT_WOPN;
       }
     }
 
@@ -1169,6 +1259,12 @@ std::vector<DivInstrument*> DivEngine::instrumentFromFile(const char* path) {
       case DIV_INSFORMAT_SBI:
         loadSBI(reader,ret,stripPath);
         break;
+      case DIV_INSFORMAT_OPLI:
+        loadOPLI(reader,ret,stripPath);
+        break;
+      case DIV_INSFORMAT_OPNI:
+        loadOPNI(reader, ret, stripPath);
+        break;
       case DIV_INSFORMAT_Y12:
         loadY12(reader,ret,stripPath);
         break;
diff --git a/src/engine/safeReader.cpp b/src/engine/safeReader.cpp
index e46827c6..97031b2b 100644
--- a/src/engine/safeReader.cpp
+++ b/src/engine/safeReader.cpp
@@ -139,7 +139,7 @@ double SafeReader::readD() {
 }
 
 String SafeReader::readString(size_t stlen) {
-  String ret(stlen, ' ');
+  String ret;
 #ifdef READ_DEBUG
   logD("SR: reading string len %d at %x",stlen,curSeek);
 #endif
diff --git a/src/gui/settings.cpp b/src/gui/settings.cpp
index 5ed9cf0a..c7a23511 100644
--- a/src/gui/settings.cpp
+++ b/src/gui/settings.cpp
@@ -2485,6 +2485,8 @@ void FurnaceGUI::applyUISettings(bool updateFonts) {
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".vgi",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".s3i",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".sbi",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
+  ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".opli",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
+  ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".opni",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".y12",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".bnk",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);
   ImGuiFileDialog::Instance()->SetFileStyle(IGFD_FileStyleByExtension,".fti",uiColors[GUI_COLOR_FILE_INSTR],ICON_FA_FILE);

From bb0253d82fc3a8f90568adead3cd93625e747d95 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 03:15:20 +1000
Subject: [PATCH 12/46] Urgh why are your operators BACKWARDS FFS

---
 src/engine/fileOpsIns.cpp | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index 87233ef6..d864bda5 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -655,12 +655,12 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       reader.seek(7, SEEK_CUR);  // skip MIDI params
       uint8_t instTypeFlags = reader.readC();  // [0EEEDCBA] - see WOPL/OPLI spec
 
-      bool is_2op = ((instTypeFlags & 0x1) > 0);
-      bool is_4op = (((instTypeFlags>>1) & 0x1) > 0);
-      bool is_2x2op = (((instTypeFlags>>2) & 0x1) > 0);
+      bool is_2op = ((instTypeFlags & 0x3) == 0);
+      bool is_4op = ((instTypeFlags & 0x1) == 1);
+      bool is_2x2op = (((instTypeFlags>>1) & 0x1) == 1);
       bool is_rhythm = (((instTypeFlags>>4) & 0x7) > 0);
 
-      auto readOpliOp = [](SafeReader& reader, DivInstrumentFM::Operator op) {
+      auto readOpliOp = [](SafeReader& reader, DivInstrumentFM::Operator& op) {
         uint8_t characteristics = reader.readC();
         uint8_t keyScaleLevel = reader.readC();
         uint8_t attackDecay = reader.readC();
@@ -687,15 +687,15 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       ins->fm.alg = (feedConnect & 0x1);
       ins->fm.fb = ((feedConnect >> 1) & 0xF);
 
-      if (is_4op) {
+      if (is_4op && !is_2x2op) {
         ins->fm.ops = 4;
         ins->fm.alg = (feedConnect & 0x1) | ((feedConnect2nd & 0x1) << 1);
-        for (int i : {0,2,1,3}) {
+        for (int i : {2,0,3,1}) {
           readOpliOp(reader, ins->fm.op[i]);
         }
       } else {
         ins->fm.ops = 2;
-        for (int i = 0; i < 2; ++i) {
+        for (int i : {1,0}) {
           readOpliOp(reader, ins->fm.op[i]);
         }
         if (is_rhythm) {
@@ -708,7 +708,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
           ins = new DivInstrument;
           ins->type = DIV_INS_OPL;
           ins->name = fmt::format("{0} (2)", insName);
-          for (int i = 0; i < 2; ++i) {
+          for (int i : {1,0}) {
             readOpliOp(reader, ins->fm.op[i]);
           }
         }

From 3865e3eac60fe6d5acc03afda5af6a544ca24b52 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 03:49:01 +1000
Subject: [PATCH 13/46] #79: OPNI support added......

---
 src/engine/fileOpsIns.cpp | 52 +++++++++++++++++++++++++++++++++++++++
 src/gui/gui.cpp           |  4 +--
 2 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index d864bda5..d541a9df 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -702,6 +702,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
           ins->fm.opllPreset = (uint8_t)(1<<4);
 
         } else if (is_2x2op) {
+          // Note: Pair detuning offset not mappable. Use E5xx effect :P
           ins->name = fmt::format("{0} (1)", insName);
           ret.push_back(ins);
 
@@ -730,6 +731,57 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
 
   try {
     reader.seek(0, SEEK_SET);
+
+    String header = reader.readString(11);
+    if (header.compare("WOPN2-INST") == 0 || header.compare("WOPN2-IN2T") == 0) {  // omfg
+      uint16_t version = reader.readS();
+      if (!(version >= 2) || version > 0xF) {
+        // version 1 doesn't have a version field........
+        reader.seek(-2, SEEK_CUR);
+      }
+
+      bool is_perc = (reader.readC() == 0x1);
+      ins->type = DIV_INS_FM;
+      ins->fm.ops = 4;
+
+      String insName = reader.readString(32);
+      ins->name = (insName.length() > 0) ? insName : stripPath;
+      reader.seek(3, SEEK_CUR);  // skip MIDI params
+      uint8_t feedAlgo = reader.readC();
+      ins->fm.alg = (feedAlgo & 0x7);
+      ins->fm.fb = ((feedAlgo>>3) & 0x7);
+      reader.readC();  // Skip global bank flags - see WOPN/OPNI spec
+
+      auto readOpniOp = [](SafeReader& reader, DivInstrumentFM::Operator& op) {
+        uint8_t dtMul = reader.readC();
+        uint8_t totalLevel = reader.readC();
+        uint8_t arRateScale = reader.readC();
+        uint8_t drAmpEnable = reader.readC();
+        uint8_t d2r = reader.readC();
+        uint8_t susRelease = reader.readC();
+        uint8_t ssgEg = reader.readC();
+
+        op.mult = dtMul & 0xF;
+        op.dt = ((dtMul >> 4) & 0x7);
+        op.tl = totalLevel & 0x3F;
+        op.rs = ((arRateScale >> 6) & 0x3);
+        op.ar = arRateScale & 0x1F;
+        op.dr = drAmpEnable & 0x1F;
+        op.am = ((drAmpEnable >> 7) & 0x1);
+        op.d2r = d2r & 0x1F;
+        op.rr = susRelease & 0xF;
+        op.sl = ((susRelease >> 4) & 0xF);
+        op.ssgEnv = ssgEg;
+      };
+
+      for (int i : {0,1,2,3}) {
+        readOpniOp(reader, ins->fm.op[i]);
+      }
+
+      // Skip rest of file
+      reader.seek(0, SEEK_END);
+      ret.push_back(ins);
+    }
   } catch (EndOfFileException& e) {
     lastError = "premature end of file";
     logE("premature end of file");
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 47b81f6e..4d6f1089 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -1290,9 +1290,9 @@ void FurnaceGUI::openFileDialog(FurnaceGUIFileDialogs type) {
       if (!dirExists(workingDirIns)) workingDirIns=getHomeDir();
       hasOpened=fileDialog->openLoad(
         "Load Instrument",
-        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.y12 *.bnk *.ff *.opm",
+        {"compatible files", "*.fui *.dmp *.tfi *.vgi *.s3i *.sbi *.opli *.opni *.y12 *.bnk *.ff *.opm",
          "all files", ".*"},
-        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.y12,.bnk,.ff,.opm},.*",
+        "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.opli,.opni,.y12,.bnk,.ff,.opm},.*",
         workingDirIns,
         dpiScale
       );

From 6638941c9dfd0c3c98c15b971dfa2377cbfc8ce8 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 04:34:32 +1000
Subject: [PATCH 14/46] Address unused stuff and CI fix

---
 src/engine/engine.h       |  1 -
 src/engine/fileOpsIns.cpp | 12 +++++++-----
 src/engine/safeReader.cpp |  5 +++++
 src/engine/safeReader.h   |  3 ++-
 4 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/src/engine/engine.h b/src/engine/engine.h
index 5e840362..b76e271e 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -31,7 +31,6 @@
 #include <mutex>
 #include <map>
 #include <queue>
-#include <sstream>
 
 #define addWarning(x) \
   if (warnings.empty()) { \
diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index d541a9df..d913d96d 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -646,7 +646,11 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
     String header = reader.readString(11);
     if (header.compare("WOPL3-INST") == 0) {
       uint16_t version = reader.readS();
-      bool isPerc = (reader.readC() == 1);
+      if (version > 3) {
+        logW("Unknown OPLI version.");
+      }
+
+      reader.readC();  // skip isPerc field
 
       ins->type = DIV_INS_OPL;
       String insName = reader.readString(32);
@@ -655,7 +659,6 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       reader.seek(7, SEEK_CUR);  // skip MIDI params
       uint8_t instTypeFlags = reader.readC();  // [0EEEDCBA] - see WOPL/OPLI spec
 
-      bool is_2op = ((instTypeFlags & 0x3) == 0);
       bool is_4op = ((instTypeFlags & 0x1) == 1);
       bool is_2x2op = (((instTypeFlags>>1) & 0x1) == 1);
       bool is_rhythm = (((instTypeFlags>>4) & 0x7) > 0);
@@ -740,7 +743,7 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
         reader.seek(-2, SEEK_CUR);
       }
 
-      bool is_perc = (reader.readC() == 0x1);
+      reader.readC(); // skip isPerc
       ins->type = DIV_INS_FM;
       ins->fm.ops = 4;
 
@@ -1006,7 +1009,6 @@ void DivEngine::loadFF(SafeReader& reader, std::vector<DivInstrument*>& ret, Str
 
 void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, String& stripPath) {
   std::vector<DivInstrument*> insList;
-  std::stringstream ss;
 
   int readCount = 0;
 
@@ -1027,7 +1029,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     patchNameRead = lfoRead = characteristicRead = m1Read = c1Read = m2Read = c2Read = false;
     newPatch = nullptr;
   };
-  auto readIntStrWithinRange = [](String& input, int limitLow, int limitHigh) {
+  auto readIntStrWithinRange = [](String&& input, int limitLow, int limitHigh) {
     int x = atoi(input.c_str());
     return (x>limitHigh) ? limitHigh :
            (x<limitLow) ? limitLow : x;
diff --git a/src/engine/safeReader.cpp b/src/engine/safeReader.cpp
index 97031b2b..9d0da1a9 100644
--- a/src/engine/safeReader.cpp
+++ b/src/engine/safeReader.cpp
@@ -198,6 +198,11 @@ String SafeReader::readString_Token(unsigned char delim) {
   }
   return ret;
 }
+String SafeReader::readString_Token() {
+  return readString_Token(' ');
+}
+
+
 
 bool SafeReader::isEOF() {
   return curSeek >= len;
diff --git a/src/engine/safeReader.h b/src/engine/safeReader.h
index 9fd0282b..4216a596 100644
--- a/src/engine/safeReader.h
+++ b/src/engine/safeReader.h
@@ -67,7 +67,8 @@ class SafeReader {
     String readString();
     String readString(size_t len);
     String readString_Line();
-    String readString_Token(unsigned char delim=' ');
+    String readString_Token(unsigned char delim);
+    String readString_Token();
     bool isEOF();
 
     SafeReader(void* b, size_t l):

From 6493a0481c80bb3cd91e6121ba2a78375a1a3e3d Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 23 Apr 2022 13:39:00 -0500
Subject: [PATCH 15/46] i hate this

---
 src/gui/gui.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 009952a6..19f2e77e 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -17,7 +17,6 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#include <SDL_keycode.h>
 #define _USE_MATH_DEFINES
 #include "gui.h"
 #include "util.h"

From 0e3dbdc1b28cfff246ed438315b17dc3716bcb9b Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 23 Apr 2022 16:52:31 -0500
Subject: [PATCH 16/46] this might fix it

---
 src/engine/platform/genesisext.cpp | 24 ++++++++++++------------
 src/engine/platform/genesisext.h   | 19 +++++++++++++++++--
 2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index d8ae8b38..eefec5d8 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -130,6 +130,9 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
       int newFreq;
       bool return2=false;
+      if (opChan[ch].portaPause) {
+        opChan[ch].baseFreq=opChan[ch].portaPauseFreq;
+      }
       if (destFreq>opChan[ch].baseFreq) {
         newFreq=opChan[ch].baseFreq+c.value;
         if (newFreq>=destFreq) {
@@ -144,23 +147,20 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
         }
       }
       // what the heck!
-      // TODO: rework!
       if (!opChan[ch].portaPause) {
         if ((newFreq&0x7ff)>1288) {
-          newFreq=(644)|((newFreq+0x800)&0xf800);
+          opChan[ch].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
           opChan[ch].portaPause=true;
-          return2=false;
-        } else if ((newFreq&0x7ff)<644) {
-          newFreq=(1287)|((newFreq-0x800)&0xf800);
-          opChan[ch].portaPause=true;
-          return2=false;
-        } else {
-          opChan[ch].freqChanged=true;
+          break;
+        }
+        if ((newFreq&0x7ff)<644) {
+          opChan[ch].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
+          opChan[ch].portaPause=true;
+          break;
         }
-      } else {
-        opChan[ch].portaPause=false;
-        opChan[ch].freqChanged=true;
       }
+      opChan[ch].portaPause=false;
+      opChan[ch].freqChanged=true;
       opChan[ch].baseFreq=newFreq;
       if (return2) return 2;
       break;
diff --git a/src/engine/platform/genesisext.h b/src/engine/platform/genesisext.h
index fc9eed89..4cdf9fc6 100644
--- a/src/engine/platform/genesisext.h
+++ b/src/engine/platform/genesisext.h
@@ -25,13 +25,28 @@ class DivPlatformGenesisExt: public DivPlatformGenesis {
   struct OpChannel {
     DivMacroInt std;
     unsigned char freqH, freqL;
-    int freq, baseFreq, pitch;
+    int freq, baseFreq, pitch, portaPauseFreq;
     unsigned char ins;
     signed char konCycles;
     bool active, insChanged, freqChanged, keyOn, keyOff, portaPause;
     int vol;
     unsigned char pan;
-    OpChannel(): freqH(0), freqL(0), freq(0), baseFreq(0), pitch(0), ins(-1), active(false), insChanged(true), freqChanged(false), keyOn(false), keyOff(false), portaPause(false), vol(0), pan(3) {}
+    OpChannel():
+      freqH(0),
+      freqL(0),
+      freq(0),
+      baseFreq(0),
+      pitch(0),
+      portaPauseFreq(0),
+      ins(-1),
+      active(false),
+      insChanged(true),
+      freqChanged(false),
+      keyOn(false),
+      keyOff(false),
+      portaPause(false),
+      vol(0),
+      pan(3) {}
   };
   OpChannel opChan[4];
   bool isOpMuted[4];

From a7828d6ad63500ef44ba0ec2683540394982f506 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 23 Apr 2022 16:54:49 -0500
Subject: [PATCH 17/46] update contributing guidelines

---
 CONTRIBUTING.md | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ad608e4c..eb25675d 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -49,12 +49,27 @@ the coding style is described here:
   - `size_t` are 32-bit or 64-bit, depending on architecture.
 - in float/double operations, always use decimal and `f` if single-precision.
   - e.g. `1.0f` or `1.0` instead of `1`.
+- prefer `NULL` over `nullptr` or any other proprietary null.
 - don't use `auto` unless needed.
+- use `String` for `std::string` (this is typedef'd in ta-utils.h).
+- prefer using operator for String (std::string) comparisons (a=="").
 
 some files (particularly the ones in `src/engine/platform/sound` and `extern/`) don't follow this style.
 
 you don't have to follow this style. I will fix it after I accept your contribution.
 
+additional guidelines:
+
+- in general **strongly** avoid breaking compatibility.
+  - do not touch loadFur/saveFur unless you know what you're doing!
+    - new fields must be at the end of each block to ensure forward compatibility
+    - likewise, the instrument read/write functions in DivInstrument have to be handled carefully
+    - any change to the format requires a version bump (see `src/engine/engine.h`).
+    - do not bump the version number under any circumstances!
+  - if you are making major changes to the playback routine, make sure to test with older songs to ensure nothing breaks.
+    - I will run a test suite to make sure this is the case.
+    - if something breaks, you might want to add a compatibility flag (this requires changing the format though).
+
 ## Demo Songs
 
 just put your demo song in `demos/`!

From dd9bb8327a0ab8588d75dbc098810753f75f9958 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sat, 23 Apr 2022 18:02:43 -0500
Subject: [PATCH 18/46] and this finally does it

the last thing to do is a compatibility flag
---
 src/engine/platform/genesis.cpp | 19 +++++++++----------
 src/engine/platform/genesis.h   |  3 ++-
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 43aae3f1..61fffcb8 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -618,6 +618,9 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
       int newFreq;
       bool return2=false;
+      if (chan[c.chan].portaPause) {
+        chan[c.chan].baseFreq=chan[c.chan].portaPauseFreq;
+      }
       if (destFreq>chan[c.chan].baseFreq) {
         newFreq=chan[c.chan].baseFreq+c.value;
         if (newFreq>=destFreq) {
@@ -634,23 +637,19 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       // check for octave boundary
       // what the heck!
       if (!chan[c.chan].portaPause) {
-        chan[c.chan].freqChanged=true;
         if ((newFreq&0x7ff)>1288) {
-          newFreq=(644)|((newFreq+0x800)&0xf800);
+          chan[c.chan].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
           chan[c.chan].portaPause=true;
-          chan[c.chan].freqChanged=false;
-          return2=false;
+          break;
         }
         if ((newFreq&0x7ff)<644) {
-          newFreq=(1287)|((newFreq-0x800)&0xf800);
+          chan[c.chan].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
           chan[c.chan].portaPause=true;
-          chan[c.chan].freqChanged=false;
-          return2=false;
+          break;
         }
-      } else {
-        chan[c.chan].portaPause=false;
-        chan[c.chan].freqChanged=true;
       }
+      chan[c.chan].portaPause=false;
+      chan[c.chan].freqChanged=true;
       chan[c.chan].baseFreq=newFreq;
       if (return2) {
         chan[c.chan].inPorta=false;
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index ce52c6df..b9430306 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -36,7 +36,7 @@ class DivPlatformGenesis: public DivDispatch {
       DivInstrumentFM state;
       DivMacroInt std;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
+      int freq, baseFreq, pitch, portaPauseFreq, note;
       unsigned char ins;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, furnaceDac, inPorta, hardReset;
       int vol, outVol;
@@ -47,6 +47,7 @@ class DivPlatformGenesis: public DivDispatch {
         freq(0),
         baseFreq(0),
         pitch(0),
+        portaPauseFreq(0),
         note(0),
         ins(-1),
         active(false),

From 18f7dcc0b0fff37545c51f98080147aa4466a752 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 12:31:37 +1000
Subject: [PATCH 19/46] Address review comments

---
 src/engine/fileOpsIns.cpp | 131 +++++++++++++++++++++-----------------
 src/engine/safeReader.cpp |  13 ++--
 src/engine/safeReader.h   |   8 +--
 3 files changed, 82 insertions(+), 70 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index d913d96d..796fd3ea 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -498,11 +498,11 @@ void DivEngine::loadS3I(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       // Skip more stuff we don't need
       reader.seek(21, SEEK_CUR);
     } else {
-      lastError = "S3I PCM samples currently not supported.";
+      lastError="S3I PCM samples currently not supported.";
       logE("S3I PCM samples currently not supported.");
     }
     ins->name = reader.readString(28);
-    ins->name = (ins->name.length() == 0) ? stripPath : ins->name;
+    ins->name = (ins->name.size() == 0) ? stripPath : ins->name;
 
     int s3i_signature = reader.readI();
 
@@ -511,7 +511,7 @@ void DivEngine::loadS3I(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       logW("S3I signature invalid.");
     };
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
     delete ins;
     return;
@@ -534,7 +534,7 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
 
     // 32-byte null terminated instrument name
     String patchName = reader.readString(32);
-    patchName = (patchName.length() == 0) ? stripPath : patchName;
+    patchName = (patchName.size() == 0) ? stripPath : patchName;
 
     auto writeOp = [](sbi_t& sbi, DivInstrumentFM::Operator& opM, DivInstrumentFM::Operator& opC) {
       opM.mult = sbi.Mcharacteristics & 0xF;
@@ -608,7 +608,7 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       if (is_6op) {
         // Freq Monster 801 6op SBIs use a 4+2op layout
         // Save the 4op portion before reading the 2op part
-        ins->name = fmt::format("{0} (4op)", ins->name);
+        ins->name = fmt::sprintf("%s (4op)", ins->name);
         ret.push_back(ins);
 
         readSbiOpData(sbi_op12, reader);
@@ -618,7 +618,7 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
         DivInstrumentFM::Operator& opC6 = ins->fm.op[1];
         ins->type = DIV_INS_OPL;
         ins->fm.ops = 2;
-        ins->name = fmt::format("{0} (2op)", patchName);
+        ins->name = fmt::sprintf("%s (2op)", patchName);
         writeOp(sbi_op12, opM6, opC6);
         ins->fm.alg = (sbi_op12.FeedConnect & 0x1);
         ins->fm.fb = ((sbi_op12.FeedConnect >> 1) & 0x7);
@@ -632,7 +632,7 @@ void DivEngine::loadSBI(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     }
 
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
     delete ins;
   }
@@ -644,7 +644,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
   try {
     reader.seek(0, SEEK_SET);
     String header = reader.readString(11);
-    if (header.compare("WOPL3-INST") == 0) {
+    if (header == "WOPL3-INST") {
       uint16_t version = reader.readS();
       if (version > 3) {
         logW("Unknown OPLI version.");
@@ -654,7 +654,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
 
       ins->type = DIV_INS_OPL;
       String insName = reader.readString(32);
-      insName = (insName.length() > 0) ? insName : stripPath;
+      insName = (insName.size() > 0) ? insName : stripPath;
       ins->name = insName;
       reader.seek(7, SEEK_CUR);  // skip MIDI params
       uint8_t instTypeFlags = reader.readC();  // [0EEEDCBA] - see WOPL/OPLI spec
@@ -693,7 +693,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       if (is_4op && !is_2x2op) {
         ins->fm.ops = 4;
         ins->fm.alg = (feedConnect & 0x1) | ((feedConnect2nd & 0x1) << 1);
-        for (int i : {2,0,3,1}) {
+        for (int i : {2,0,3,1}) { // omfg >_<
           readOpliOp(reader, ins->fm.op[i]);
         }
       } else {
@@ -706,12 +706,12 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
 
         } else if (is_2x2op) {
           // Note: Pair detuning offset not mappable. Use E5xx effect :P
-          ins->name = fmt::format("{0} (1)", insName);
+          ins->name = fmt::sprintf("%s (1)", insName);
           ret.push_back(ins);
 
           ins = new DivInstrument;
           ins->type = DIV_INS_OPL;
-          ins->name = fmt::format("{0} (2)", insName);
+          ins->name = fmt::sprintf("%s (2)", insName);
           for (int i : {1,0}) {
             readOpliOp(reader, ins->fm.op[i]);
           }
@@ -723,7 +723,7 @@ void DivEngine::loadOPLI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       ret.push_back(ins);
     }
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
     delete ins;
   }
@@ -736,7 +736,7 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
     reader.seek(0, SEEK_SET);
 
     String header = reader.readString(11);
-    if (header.compare("WOPN2-INST") == 0 || header.compare("WOPN2-IN2T") == 0) {  // omfg
+    if (header == "WOPN2-INST" || header == "WOPN2-IN2T") {  // omfg >_<
       uint16_t version = reader.readS();
       if (!(version >= 2) || version > 0xF) {
         // version 1 doesn't have a version field........
@@ -748,7 +748,7 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       ins->fm.ops = 4;
 
       String insName = reader.readString(32);
-      ins->name = (insName.length() > 0) ? insName : stripPath;
+      ins->name = (insName.size() > 0) ? insName : stripPath;
       reader.seek(3, SEEK_CUR);  // skip MIDI params
       uint8_t feedAlgo = reader.readC();
       ins->fm.alg = (feedAlgo & 0x7);
@@ -777,7 +777,7 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
         op.ssgEnv = ssgEg;
       };
 
-      for (int i : {0,1,2,3}) {
+      for (int i = 0; i < 4; ++i) {
         readOpniOp(reader, ins->fm.op[i]);
       }
 
@@ -786,7 +786,7 @@ void DivEngine::loadOPNI(SafeReader& reader, std::vector<DivInstrument*>& ret, S
       ret.push_back(ins);
     }
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
     delete ins;
   }
@@ -801,7 +801,7 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     ins->fm.ops = 4;
     ins->name = stripPath;
 
-    for (int i : {0,1,2,3}) {
+    for (int i; i < 4; ++i) {
       DivInstrumentFM::Operator& insOp = ins->fm.op[i];
       uint8_t tmp = reader.readC();
       insOp.mult = tmp & 0xF;
@@ -825,7 +825,7 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     reader.seek(62, SEEK_CUR);
     ret.push_back(ins);
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
     delete ins;
   }
@@ -904,14 +904,14 @@ void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, St
 
         ins->fm.op[0].ws = reader.readC();
         ins->fm.op[1].ws = reader.readC();
-        ins->name = instNames[i]->length() > 0 ? (*instNames[i]) : fmt::format("{0}[{1}]", stripPath, i);
+        ins->name = instNames[i]->length() > 0 ? (*instNames[i]) : fmt::sprintf("%s[%d]", stripPath, i);
       }
       reader.seek(0, SEEK_END);
 
     } catch (EndOfFileException& e) {
-      lastError = "premature end of file";
+      lastError="premature end of file";
       logE("premature end of file");
-      for (int i = readCount; i >= 0; --i) {
+      for (int i = readCount - 1; i >= 0; --i) {
         delete insList[i];
       }
       is_failed = true;
@@ -919,7 +919,7 @@ void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, St
 
   } else {
     // assume GEMS BNK for now.
-    lastError = "GEMS BNK currently not supported.";
+    lastError="GEMS BNK currently not supported.";
     logE("GEMS BNK currently not supported.");
   }
 
@@ -994,9 +994,9 @@ void DivEngine::loadFF(SafeReader& reader, std::vector<DivInstrument*>& ret, Str
       ++readCount;
     }
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
-    for (int i = readCount; i >= 0; --i) {
+    for (int i = readCount - 1; i >= 0; --i) {
       delete insList[i];
     }
     return;
@@ -1011,6 +1011,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
   std::vector<DivInstrument*> insList;
 
   int readCount = 0;
+  bool is_failed = false;
 
   bool patchNameRead = false,
        lfoRead = false,
@@ -1020,52 +1021,55 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
        m2Read = false,
        c2Read = false;
 
-  DivInstrument* newPatch = nullptr;
+  DivInstrument* newPatch = NULL;
   
   auto completePatchRead = [&]() {
     return patchNameRead && lfoRead && characteristicRead && m1Read && c1Read && m2Read && c2Read;
   };
   auto resetPatchRead = [&]() {
     patchNameRead = lfoRead = characteristicRead = m1Read = c1Read = m2Read = c2Read = false;
-    newPatch = nullptr;
+    newPatch = NULL;
   };
   auto readIntStrWithinRange = [](String&& input, int limitLow, int limitHigh) {
-    int x = atoi(input.c_str());
+    int x = std::stoi(input.c_str());
+    if (x > limitHigh || x < limitLow) {
+      throw std::invalid_argument(fmt::sprintf("%s is out of bounds of range [%d..%d]", input, limitLow, limitHigh));
+    }
     return (x>limitHigh) ? limitHigh :
            (x<limitLow) ? limitLow : x;
   };
   auto readOpmOperator = [&](SafeReader& reader, DivInstrumentFM::Operator& op) {
-    op.ar = readIntStrWithinRange(reader.readString_Token(), 0, 31);
-    op.dr = readIntStrWithinRange(reader.readString_Token(), 0, 31);
-    op.d2r = readIntStrWithinRange(reader.readString_Token(), 0, 31);
-    op.rr = readIntStrWithinRange(reader.readString_Token(), 0, 31);
-    op.sl = readIntStrWithinRange(reader.readString_Token(), 0, 15);
-    op.tl = readIntStrWithinRange(reader.readString_Token(), 0, 127);
-    op.rs = readIntStrWithinRange(reader.readString_Token(), 0, 3);;
-    op.mult = readIntStrWithinRange(reader.readString_Token(), 0, 15);
-    op.dt = readIntStrWithinRange(reader.readString_Token(), 0, 7);
+    op.ar = readIntStrWithinRange(reader.readStringToken(), 0, 31);
+    op.dr = readIntStrWithinRange(reader.readStringToken(), 0, 31);
+    op.d2r = readIntStrWithinRange(reader.readStringToken(), 0, 31);
+    op.rr = readIntStrWithinRange(reader.readStringToken(), 0, 31);
+    op.sl = readIntStrWithinRange(reader.readStringToken(), 0, 15);
+    op.tl = readIntStrWithinRange(reader.readStringToken(), 0, 127);
+    op.rs = readIntStrWithinRange(reader.readStringToken(), 0, 3);;
+    op.mult = readIntStrWithinRange(reader.readStringToken(), 0, 15);
+    op.dt = readIntStrWithinRange(reader.readStringToken(), 0, 7);
     op.dt = (op.dt >= 4) ? (7 - op.dt) : (op.dt + 3);
-    op.dt2 = readIntStrWithinRange(reader.readString_Token(), 0, 3);
-    op.am = readIntStrWithinRange(reader.readString_Token(), 0, 1);
+    op.dt2 = readIntStrWithinRange(reader.readStringToken(), 0, 3);
+    op.am = readIntStrWithinRange(reader.readStringToken(), 0, 1);
   };
 
   try {
     reader.seek(0, SEEK_SET);
     while (!reader.isEOF()) {
-      String token = reader.readString_Token();
-      if (token.length() == 0) {
+      String token = reader.readStringToken();
+      if (token.size() == 0) {
         continue;
       }
 
       if (token.compare(0,2,"//") == 0) {
         if (!reader.isEOF()) {
-          reader.readString_Line();
+          reader.readStringLine();
         }
         continue;
       }
 
       // At this point we know any other line would be associated with patch params
-      if (newPatch == nullptr) {
+      if (newPatch == NULL) {
         newPatch = new DivInstrument;
         newPatch->type = DIV_INS_FM;
         newPatch->fm.ops = 4;
@@ -1074,23 +1078,23 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       // Read each line for their respective params. They may not be written in the same LINE order but they 
       // must absolutely be properly grouped per patch! Line prefixes must be separated by a space! (see inline comments)
       
-      if (token.length() >= 2) {
+      if (token.size() >= 2) {
         if (token[0] == '@') {
           // @:123 Name of patch
           // Note: Fallback to bank filename and current patch number in _file_ order (not @n order)
-          newPatch->name = reader.readString_Line();
-          newPatch->name = newPatch->name.length() > 0 ? newPatch->name : fmt::format("{0}[{1}]", stripPath, readCount);
+          newPatch->name = reader.readStringLine();
+          newPatch->name = newPatch->name.size() > 0 ? newPatch->name : fmt::sprintf("%s[%d]", stripPath, readCount);
           patchNameRead = true;
 
         } else if (token.compare(0,3,"CH:") == 0) {
           // CH: PAN FL CON AMS PMS SLOT NE
-          reader.readString_Token(); // skip PAN
-          newPatch->fm.fb = readIntStrWithinRange(reader.readString_Token(), 0, 7);
-          newPatch->fm.alg = readIntStrWithinRange(reader.readString_Token(), 0, 7);
-          newPatch->fm.ams = readIntStrWithinRange(reader.readString_Token(), 0, 4);
-          newPatch->fm.fms = readIntStrWithinRange(reader.readString_Token(), 0, 7);
-          reader.readString_Token(); // skip SLOT
-          reader.readString_Token(); // skip NE
+          reader.readStringToken(); // skip PAN
+          newPatch->fm.fb = readIntStrWithinRange(reader.readStringToken(), 0, 7);
+          newPatch->fm.alg = readIntStrWithinRange(reader.readStringToken(), 0, 7);
+          newPatch->fm.ams = readIntStrWithinRange(reader.readStringToken(), 0, 4);
+          newPatch->fm.fms = readIntStrWithinRange(reader.readStringToken(), 0, 7);
+          reader.readStringToken(); // skip SLOT
+          reader.readStringToken(); // skip NE
           characteristicRead = true;
 
         } else if (token.compare(0,3,"C1:") == 0) {
@@ -1116,12 +1120,12 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
         } else if (token.compare(0,4,"LFO:") == 0) {
           // LFO: LFRQ AMD PMD WF NFRQ
           // Furnace patches do not store these as they are chip-global.
-          reader.readString_Line();
+          reader.readStringLine();
           lfoRead = true;
 
         } else {
           // other unsupported lines ignored.
-          reader.readString_Line();
+          reader.readStringLine();
         }
       }
 
@@ -1132,7 +1136,7 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       }
     }
 
-    if (newPatch != nullptr) {
+    if (newPatch != NULL) {
       addWarning("Last OPM patch read was incomplete and therefore not imported.");
       logW("Last OPM patch read was incomplete and therefore not imported.");
       delete newPatch;
@@ -1142,12 +1146,21 @@ void DivEngine::loadOPM(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       ret.push_back(insList[i]);
     }
   } catch (EndOfFileException& e) {
-    lastError = "premature end of file";
+    lastError="premature end of file";
     logE("premature end of file");
-    for (int i = readCount; i >= 0; --i) {
+    is_failed = true;
+  } catch (std::invalid_argument& e) {
+    lastError=fmt::sprintf("Invalid value found in patch file. %s", e.what());
+    logE("Invalid value found in patch file.");
+    logE(e.what());
+    is_failed = true;
+  }
+
+  if (is_failed) {
+    for (int i = readCount - 1; i >= 0; --i) {
       delete insList[i];
     }
-    if (newPatch != nullptr) {
+    if (newPatch != NULL) {
       delete newPatch;
     }
   }
diff --git a/src/engine/safeReader.cpp b/src/engine/safeReader.cpp
index 9d0da1a9..eb9f63ae 100644
--- a/src/engine/safeReader.cpp
+++ b/src/engine/safeReader.cpp
@@ -165,7 +165,7 @@ String SafeReader::readString() {
   return ret;
 }
 
-String SafeReader::readString_Line() {
+String SafeReader::readStringLine() {
   String ret;
   unsigned char c;
   if (isEOF()) throw EndOfFileException(this, len);
@@ -179,7 +179,7 @@ String SafeReader::readString_Line() {
   return ret;
 }
 
-String SafeReader::readString_Token(unsigned char delim) {
+String SafeReader::readStringToken(unsigned char delim) {
   String ret;
   unsigned char c;
   if (isEOF()) throw EndOfFileException(this, len);
@@ -198,12 +198,11 @@ String SafeReader::readString_Token(unsigned char delim) {
   }
   return ret;
 }
-String SafeReader::readString_Token() {
-  return readString_Token(' ');
+
+String SafeReader::readStringToken() {
+  return readStringToken(' ');
 }
 
-
-
-bool SafeReader::isEOF() {
+inline bool SafeReader::isEOF() {
   return curSeek >= len;
 }
\ No newline at end of file
diff --git a/src/engine/safeReader.h b/src/engine/safeReader.h
index 4216a596..5f27383c 100644
--- a/src/engine/safeReader.h
+++ b/src/engine/safeReader.h
@@ -66,10 +66,10 @@ class SafeReader {
     double readD_BE();
     String readString();
     String readString(size_t len);
-    String readString_Line();
-    String readString_Token(unsigned char delim);
-    String readString_Token();
-    bool isEOF();
+    String readStringLine();
+    String readStringToken(unsigned char delim);
+    String readStringToken();
+    inline bool isEOF();
 
     SafeReader(void* b, size_t l):
       buf((unsigned char*)b),

From 580cff9d32417684823a0f4537d6958ecdc6a37f Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 12:37:49 +1000
Subject: [PATCH 20/46] Decided to EOF fail seeks beyond bounds

---
 src/engine/fileOpsIns.cpp | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index 796fd3ea..ce03915b 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -818,11 +818,15 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       insOp.rr = tmp & 0xF;
       insOp.sl = ((tmp >> 4) & 0xF);
       insOp.ssgEnv = reader.readC();
-      reader.seek(9, SEEK_CUR);
+      if (!reader.seek(9, SEEK_CUR)) {
+        throw EndOfFileException(&reader, reader.tell() + 9);
+      }
     }
     ins->fm.alg = reader.readC();
     ins->fm.fb = reader.readC();
-    reader.seek(62, SEEK_CUR);
+    if (!reader.seek(62, SEEK_CUR)) {
+      throw EndOfFileException(&reader, reader.tell() + 62);
+    }
     ret.push_back(ins);
   } catch (EndOfFileException& e) {
     lastError="premature end of file";
@@ -858,7 +862,9 @@ void DivEngine::loadBNK(SafeReader& reader, std::vector<DivInstrument*>& ret, St
       }
 
       // Seek to BNK data
-      reader.seek(data_offset, SEEK_SET);
+      if (!reader.seek(data_offset, SEEK_SET)) {
+        throw EndOfFileException(&reader, data_offset);
+      };
 
       // Read until EOF
       for (int i = 0; i < readCount; ++i) {

From 2a48adfde8a9d42cdd8ce23aa08b683ae7ade504 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 13:43:56 +1000
Subject: [PATCH 21/46] Inline error

---
 src/engine/safeReader.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/engine/safeReader.h b/src/engine/safeReader.h
index 5f27383c..e95c90a0 100644
--- a/src/engine/safeReader.h
+++ b/src/engine/safeReader.h
@@ -69,7 +69,7 @@ class SafeReader {
     String readStringLine();
     String readStringToken(unsigned char delim);
     String readStringToken();
-    inline bool isEOF();
+    bool isEOF();
 
     SafeReader(void* b, size_t l):
       buf((unsigned char*)b),

From 2b90bd6c66b82d4589b0bab2b01c1b3bd249b520 Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 13:55:21 +1000
Subject: [PATCH 22/46]  = 0

---
 src/engine/fileOpsIns.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index ce03915b..e080b779 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -801,7 +801,7 @@ void DivEngine::loadY12(SafeReader& reader, std::vector<DivInstrument*>& ret, St
     ins->fm.ops = 4;
     ins->name = stripPath;
 
-    for (int i; i < 4; ++i) {
+    for (int i = 0; i < 4; ++i) {
       DivInstrumentFM::Operator& insOp = ins->fm.op[i];
       uint8_t tmp = reader.readC();
       insOp.mult = tmp & 0xF;

From 798bc08431419fe811262be24b5d1d9016d9434a Mon Sep 17 00:00:00 2001
From: James Alan Nguyen <djtubig.malicex@gmail.com>
Date: Sun, 24 Apr 2022 14:04:56 +1000
Subject: [PATCH 23/46] =?UTF-8?q?verdammte=20compilerschie=C3=9F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/engine/safeReader.cpp | 4 ----
 src/engine/safeReader.h   | 2 +-
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/engine/safeReader.cpp b/src/engine/safeReader.cpp
index eb9f63ae..36d6097d 100644
--- a/src/engine/safeReader.cpp
+++ b/src/engine/safeReader.cpp
@@ -202,7 +202,3 @@ String SafeReader::readStringToken(unsigned char delim) {
 String SafeReader::readStringToken() {
   return readStringToken(' ');
 }
-
-inline bool SafeReader::isEOF() {
-  return curSeek >= len;
-}
\ No newline at end of file
diff --git a/src/engine/safeReader.h b/src/engine/safeReader.h
index e95c90a0..e21311f9 100644
--- a/src/engine/safeReader.h
+++ b/src/engine/safeReader.h
@@ -69,7 +69,7 @@ class SafeReader {
     String readStringLine();
     String readStringToken(unsigned char delim);
     String readStringToken();
-    bool isEOF();
+    inline bool isEOF() { return curSeek >= len; };
 
     SafeReader(void* b, size_t l):
       buf((unsigned char*)b),

From 23be8d93367f0960338725fb26cf7f9e65437fcf Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 14:40:07 -0500
Subject: [PATCH 24/46] the final piece of f-num/block work

---
 papers/format.md                   |  6 +++++-
 src/engine/engine.h                |  4 ++--
 src/engine/fileOps.cpp             | 14 ++++++++++++--
 src/engine/platform/genesisext.cpp | 20 ++++++++++++++------
 src/engine/song.h                  |  4 +++-
 src/gui/compatFlags.cpp            |  6 +++++-
 6 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/papers/format.md b/papers/format.md
index 7775e9ea..ef8ab7e5 100644
--- a/papers/format.md
+++ b/papers/format.md
@@ -29,6 +29,8 @@ furthermore, an `or reserved` indicates this field is always present, but is res
 
 the format versions are:
 
+- 85: Furnace dev85
+- 84: Furnace dev84
 - 83: Furnace dev83
 - 82: Furnace dev82
 - 81: Furnace dev81
@@ -269,7 +271,9 @@ size | description
   1  | ExtCh channel state is shared (>=78) or reserved
   1  | ignore DAC mode change outside of intended channel (>=83) or reserved
   1  | E1xx and E2xx also take priority over Slide00 (>=83) or reserved
- 23  | reserved
+  1  | new Sega PCM (with macros and proper vol/pan) (>=84) or reserved
+  1  | weird f-num/block-based chip pitch slides (>=85) or reserved
+ 21  | reserved
 ```
 
 # instrument
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 515b9c59..81e15f72 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -43,8 +43,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev84"
-#define DIV_ENGINE_VERSION 84
+#define DIV_VERSION "dev85"
+#define DIV_ENGINE_VERSION 85
 
 // for imports
 #define DIV_VERSION_MOD 0xff01
diff --git a/src/engine/fileOps.cpp b/src/engine/fileOps.cpp
index aee7de71..48ef68bb 100644
--- a/src/engine/fileOps.cpp
+++ b/src/engine/fileOps.cpp
@@ -162,6 +162,7 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
     ds.gbInsAffectsEnvelope=true;
     ds.ignoreDACModeOutsideIntendedChannel=false;
     ds.e1e2AlsoTakePriority=true;
+    ds.fbPortaPause=true;
 
     // 1.1 compat flags
     if (ds.version>24) {
@@ -993,6 +994,9 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
     if (ds.version<84) {
       ds.newSegaPCM=false;
     }
+    if (ds.version<85) {
+      ds.fbPortaPause=true;
+    }
     ds.isDMF=false;
 
     reader.readS(); // reserved
@@ -1342,7 +1346,12 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
       } else {
         reader.readC();
       }
-      for (int i=0; i<22; i++) {
+      if (ds.version>=85) {
+        ds.fbPortaPause=reader.readC();
+      } else {
+        reader.readC();
+      }
+      for (int i=0; i<21; i++) {
         reader.readC();
       }
     }
@@ -2283,7 +2292,8 @@ SafeWriter* DivEngine::saveFur(bool notPrimary) {
   w->writeC(song.ignoreDACModeOutsideIntendedChannel);
   w->writeC(song.e1e2AlsoTakePriority);
   w->writeC(song.newSegaPCM);
-  for (int i=0; i<22; i++) {
+  w->writeC(song.fbPortaPause);
+  for (int i=0; i<21; i++) {
     w->writeC(0);
   }
 
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index eefec5d8..479e4242 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -149,14 +149,22 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       // what the heck!
       if (!opChan[ch].portaPause) {
         if ((newFreq&0x7ff)>1288) {
-          opChan[ch].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
-          opChan[ch].portaPause=true;
-          break;
+          if (parent->song.fbPortaPause) {
+            opChan[ch].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
+            opChan[ch].portaPause=true;
+            break;
+          } else {
+            newFreq=(newFreq>>1)|((newFreq+0x800)&0xf800);
+          }
         }
         if ((newFreq&0x7ff)<644) {
-          opChan[ch].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
-          opChan[ch].portaPause=true;
-          break;
+          if (parent->song.fbPortaPause) {
+            opChan[ch].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
+            opChan[ch].portaPause=true;
+            break;
+          } else {
+            newFreq=(newFreq<<1)|((newFreq-0x800)&0xf800);
+          }
         }
       }
       opChan[ch].portaPause=false;
diff --git a/src/engine/song.h b/src/engine/song.h
index 20b17ae6..9b9187ac 100644
--- a/src/engine/song.h
+++ b/src/engine/song.h
@@ -324,6 +324,7 @@ struct DivSong {
   bool ignoreDACModeOutsideIntendedChannel;
   bool e1e2AlsoTakePriority;
   bool newSegaPCM;
+  bool fbPortaPause;
 
   DivOrders orders;
   std::vector<DivInstrument*> ins;
@@ -406,7 +407,8 @@ struct DivSong {
     sharedExtStat(true),
     ignoreDACModeOutsideIntendedChannel(false),
     e1e2AlsoTakePriority(false),
-    newSegaPCM(true) {
+    newSegaPCM(true),
+    fbPortaPause(false) {
     for (int i=0; i<32; i++) {
       system[i]=DIV_SYSTEM_NULL;
       systemVol[i]=64;
diff --git a/src/gui/compatFlags.cpp b/src/gui/compatFlags.cpp
index d2035ff7..8d1fd6d1 100644
--- a/src/gui/compatFlags.cpp
+++ b/src/gui/compatFlags.cpp
@@ -101,6 +101,10 @@ void FurnaceGUI::drawCompatFlags() {
     if (ImGui::IsItemHovered()) {
       ImGui::SetTooltip("simulates a bug in where portamento does not work after sliding.");
     }
+    ImGui::Checkbox("FM pitch slide octave boundary odd behavior",&e->song.fbPortaPause);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("if this is on, a pitch slide that crosses the octave boundary will stop for one tick and then continue from the nearest octave boundary.\nfor .dmf compatibility.");
+    }
     ImGui::Checkbox("Apply Game Boy envelope on note-less instrument change",&e->song.gbInsAffectsEnvelope);
     if (ImGui::IsItemHovered()) {
       ImGui::SetTooltip("if this is on, an instrument change will also affect the envelope.");
@@ -173,4 +177,4 @@ void FurnaceGUI::drawCompatFlags() {
   }
   if (ImGui::IsWindowFocused(ImGuiFocusedFlags_ChildWindows)) curWindow=GUI_WINDOW_COMPAT_FLAGS;
   ImGui::End();
-}
\ No newline at end of file
+}

From e414056f2d82e355c68c7a20976e7dc2572b3284 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 16:57:58 -0500
Subject: [PATCH 25/46] prepare for a clear option

---
 src/gui/gui.cpp | 31 +++++++++++++++++++++++++++++--
 src/gui/gui.h   |  1 +
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index e87c1e8e..1a9e537c 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -2711,8 +2711,10 @@ bool FurnaceGUI::loop() {
       if (ImGui::MenuItem("redo",BIND_FOR(GUI_ACTION_REDO))) doRedo();
       ImGui::Separator();
       editOptions(true);
-      /*ImGui::Separator();
-      ImGui::MenuItem("clear...");*/
+      ImGui::Separator();
+      if (ImGui::MenuItem("clear...")) {
+        showWarning("Are you sure you want to clear...",GUI_WARN_CLEAR);
+      }
       ImGui::EndMenu();
     }
     if (ImGui::BeginMenu("settings")) {
@@ -3370,6 +3372,31 @@ bool FurnaceGUI::loop() {
             ImGui::CloseCurrentPopup();
           }
           break;
+        case GUI_WARN_CLEAR:
+          if (ImGui::Button("Song (orders and patterns)")) {
+            ImGui::CloseCurrentPopup();
+          }
+          ImGui::SameLine();
+          if (ImGui::Button("Pattern")) {
+            ImGui::CloseCurrentPopup();
+          }
+          ImGui::SameLine();
+          if (ImGui::Button("Instruments")) {
+            ImGui::CloseCurrentPopup();
+          }
+          ImGui::SameLine();
+          if (ImGui::Button("Wavetables")) {
+            ImGui::CloseCurrentPopup();
+          }
+          ImGui::SameLine();
+          if (ImGui::Button("Samples")) {
+            ImGui::CloseCurrentPopup();
+          }
+
+          if (ImGui::Button("Wait! What am I doing?")) {
+            ImGui::CloseCurrentPopup();
+          }
+          break;
         case GUI_WARN_GENERIC:
           if (ImGui::Button("OK")) {
             ImGui::CloseCurrentPopup();
diff --git a/src/gui/gui.h b/src/gui/gui.h
index 6c50a914..8c850fd0 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -264,6 +264,7 @@ enum FurnaceGUIWarnings {
   GUI_WARN_RESET_COLORS,
   GUI_WARN_RESET_KEYBINDS,
   GUI_WARN_CLOSE_SETTINGS,
+  GUI_WARN_CLEAR,
   GUI_WARN_GENERIC
 };
 

From 521b3116922766344071b0f0d0a7acf4e767da99 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 17:39:18 -0500
Subject: [PATCH 26/46] GUI: implement clear

---
 src/engine/song.cpp | 36 ++++++++++++++++++++++++++++++++++++
 src/engine/song.h   | 21 +++++++++++++++++++++
 src/gui/gui.cpp     | 40 +++++++++++++++++++++++++++++++++++++++-
 3 files changed, 96 insertions(+), 1 deletion(-)

diff --git a/src/engine/song.cpp b/src/engine/song.cpp
index 4d2aef8d..7a815eb1 100644
--- a/src/engine/song.cpp
+++ b/src/engine/song.cpp
@@ -19,21 +19,57 @@
 
 #include "song.h"
 
+void DivSong::clearSongData() {
+  for (int i=0; i<DIV_MAX_CHANS; i++) {
+    pat[i].wipePatterns();
+  }
+
+  memset(orders.ord,0,DIV_MAX_CHANS*256);
+  ordersLen=1;
+}
+
+void DivSong::clearInstruments() {
+  for (DivInstrument* i: ins) {
+    delete i;
+  }
+  ins.clear();
+  insLen=0;
+}
+
+void DivSong::clearWavetables() {
+  for (DivWavetable* i: wave) {
+    delete i;
+  }
+  wave.clear();
+  waveLen=0;
+}
+
+void DivSong::clearSamples() {
+  for (DivSample* i: sample) {
+    delete i;
+  }
+  sample.clear();
+  sampleLen=0;
+}
+
 void DivSong::unload() {
   for (DivInstrument* i: ins) {
     delete i;
   }
   ins.clear();
+  insLen=0;
 
   for (DivWavetable* i: wave) {
     delete i;
   }
   wave.clear();
+  waveLen=0;
 
   for (DivSample* i: sample) {
     delete i;
   }
   sample.clear();
+  sampleLen=0;
 
   for (int i=0; i<DIV_MAX_CHANS; i++) {
     pat[i].wipePatterns();
diff --git a/src/engine/song.h b/src/engine/song.h
index 9b9187ac..11264558 100644
--- a/src/engine/song.h
+++ b/src/engine/song.h
@@ -339,6 +339,27 @@ struct DivSong {
   DivWavetable nullWave;
   DivSample nullSample;
 
+  /**
+   * clear orders and patterns.
+   */
+  void clearSongData();
+
+  /**
+   * clear instruments.
+   */
+  void clearInstruments();
+
+  /**
+   * clear wavetables.
+   */
+  void clearWavetables();
+
+  /**
+   * clear samples.
+   */
+  void clearSamples();
+
+
   /**
    * unloads the song, freeing all memory associated with it.
    * use before destroying the object.
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 1a9e537c..a3c41317 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -3374,26 +3374,64 @@ bool FurnaceGUI::loop() {
           break;
         case GUI_WARN_CLEAR:
           if (ImGui::Button("Song (orders and patterns)")) {
+            stop();
+            e->lockEngine([this]() {
+              e->song.clearSongData();
+            });
+            e->setOrder(0);
+            curOrder=0;
+            oldOrder=0;
+            oldOrder1=0;
+            MARK_MODIFIED;
             ImGui::CloseCurrentPopup();
           }
           ImGui::SameLine();
           if (ImGui::Button("Pattern")) {
+            stop();
+            e->lockEngine([this]() {
+              for (int i=0; i<e->getTotalChannelCount(); i++) {
+                DivPattern* pat=e->song.pat[i].getPattern(e->song.orders.ord[i][curOrder],true);
+                memset(pat->data,-1,256*32*sizeof(short));
+                for (int j=0; j<256; j++) {
+                  pat->data[j][0]=0;
+                  pat->data[j][1]=0;
+                }
+              }
+            });
+            MARK_MODIFIED;
             ImGui::CloseCurrentPopup();
           }
           ImGui::SameLine();
           if (ImGui::Button("Instruments")) {
+            stop();
+            e->lockEngine([this]() {
+              e->song.clearInstruments();
+            });
+            curIns=-1;
+            MARK_MODIFIED;
             ImGui::CloseCurrentPopup();
           }
           ImGui::SameLine();
           if (ImGui::Button("Wavetables")) {
+            stop();
+            e->lockEngine([this]() {
+              e->song.clearWavetables();
+            });
+            curWave=0;
+            MARK_MODIFIED;
             ImGui::CloseCurrentPopup();
           }
           ImGui::SameLine();
           if (ImGui::Button("Samples")) {
+            stop();
+            e->lockEngine([this]() {
+              e->song.clearSamples();
+            });
+            curSample=0;
             ImGui::CloseCurrentPopup();
           }
 
-          if (ImGui::Button("Wait! What am I doing?")) {
+          if (ImGui::Button("Wait! What am I doing? Cancel!")) {
             ImGui::CloseCurrentPopup();
           }
           break;

From f99ba810feab7b3bed0b5e8b46174df2a3e0617c Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 17:48:04 -0500
Subject: [PATCH 27/46] PC speaker: fix timer issue

---
 src/engine/platform/pcspkr.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/engine/platform/pcspkr.cpp b/src/engine/platform/pcspkr.cpp
index b34d16f2..8a00c563 100644
--- a/src/engine/platform/pcspkr.cpp
+++ b/src/engine/platform/pcspkr.cpp
@@ -53,6 +53,7 @@ void DivPlatformPCSpeaker::acquire_unfilt(short* bufL, short* bufR, size_t start
   for (size_t i=start; i<start+len; i++) {
     if (on) {
       pos-=PCSPKR_DIVIDER;
+      if (pos>freq) pos=freq;
       while (pos<0) {
         if (freq<1) {
           pos=1;
@@ -71,6 +72,7 @@ void DivPlatformPCSpeaker::acquire_cone(short* bufL, short* bufR, size_t start,
   for (size_t i=start; i<start+len; i++) {
     if (on) {
       pos-=PCSPKR_DIVIDER;
+      if (pos>freq) pos=freq;
       while (pos<0) {
         if (freq<1) {
           pos=1;
@@ -95,6 +97,7 @@ void DivPlatformPCSpeaker::acquire_piezo(short* bufL, short* bufR, size_t start,
   for (size_t i=start; i<start+len; i++) {
     if (on) {
       pos-=PCSPKR_DIVIDER;
+      if (pos>freq) pos=freq;
       while (pos<0) {
         if (freq<1) {
           pos=1;

From bd68ef5cc3efdc439aa7f7418dc8028f65f6d106 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 18:12:18 -0500
Subject: [PATCH 28/46] dev86 - SN duty macro phase reset fix

---
 papers/format.md            |  4 +++-
 src/engine/engine.h         |  4 ++--
 src/engine/fileOps.cpp      | 14 ++++++++++++--
 src/engine/platform/sms.cpp | 10 ++++++----
 src/engine/song.h           |  4 +++-
 src/gui/compatFlags.cpp     |  4 ++++
 6 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/papers/format.md b/papers/format.md
index ef8ab7e5..207b232a 100644
--- a/papers/format.md
+++ b/papers/format.md
@@ -29,6 +29,7 @@ furthermore, an `or reserved` indicates this field is always present, but is res
 
 the format versions are:
 
+- 86: Furnace dev86
 - 85: Furnace dev85
 - 84: Furnace dev84
 - 83: Furnace dev83
@@ -273,7 +274,8 @@ size | description
   1  | E1xx and E2xx also take priority over Slide00 (>=83) or reserved
   1  | new Sega PCM (with macros and proper vol/pan) (>=84) or reserved
   1  | weird f-num/block-based chip pitch slides (>=85) or reserved
- 21  | reserved
+  1  | SN duty macro always resets phase (>=86) or reserved
+ 20  | reserved
 ```
 
 # instrument
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 427215df..3bd1db3d 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -43,8 +43,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev85"
-#define DIV_ENGINE_VERSION 85
+#define DIV_VERSION "dev86"
+#define DIV_ENGINE_VERSION 86
 
 // for imports
 #define DIV_VERSION_MOD 0xff01
diff --git a/src/engine/fileOps.cpp b/src/engine/fileOps.cpp
index 48ef68bb..38b33502 100644
--- a/src/engine/fileOps.cpp
+++ b/src/engine/fileOps.cpp
@@ -163,6 +163,7 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
     ds.ignoreDACModeOutsideIntendedChannel=false;
     ds.e1e2AlsoTakePriority=true;
     ds.fbPortaPause=true;
+    ds.snDutyReset=true;
 
     // 1.1 compat flags
     if (ds.version>24) {
@@ -997,6 +998,9 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
     if (ds.version<85) {
       ds.fbPortaPause=true;
     }
+    if (ds.version<86) {
+      ds.snDutyReset=true;
+    }
     ds.isDMF=false;
 
     reader.readS(); // reserved
@@ -1351,7 +1355,12 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
       } else {
         reader.readC();
       }
-      for (int i=0; i<21; i++) {
+      if (ds.version>=86) {
+        ds.snDutyReset=reader.readC();
+      } else {
+        reader.readC();
+      }
+      for (int i=0; i<20; i++) {
         reader.readC();
       }
     }
@@ -2293,7 +2302,8 @@ SafeWriter* DivEngine::saveFur(bool notPrimary) {
   w->writeC(song.e1e2AlsoTakePriority);
   w->writeC(song.newSegaPCM);
   w->writeC(song.fbPortaPause);
-  for (int i=0; i<21; i++) {
+  w->writeC(song.snDutyReset);
+  for (int i=0; i<20; i++) {
     w->writeC(0);
   }
 
diff --git a/src/engine/platform/sms.cpp b/src/engine/platform/sms.cpp
index af339f6e..c32548b5 100644
--- a/src/engine/platform/sms.cpp
+++ b/src/engine/platform/sms.cpp
@@ -86,11 +86,13 @@ void DivPlatformSMS::tick(bool sysTick) {
     }
     if (i==3) {
       if (chan[i].std.duty.had) {
-        snNoiseMode=chan[i].std.duty.val;
-        if (chan[i].std.duty.val<2) {
-          chan[3].freqChanged=false;
+        if (chan[i].std.duty.val!=snNoiseMode || parent->song.snDutyReset) {
+          snNoiseMode=chan[i].std.duty.val;
+          if (chan[i].std.duty.val<2) {
+            chan[3].freqChanged=false;
+          }
+          updateSNMode=true;
         }
-        updateSNMode=true;
       }
       if (chan[i].std.phaseReset.had) {
         if (chan[i].std.phaseReset.val==1) {
diff --git a/src/engine/song.h b/src/engine/song.h
index 11264558..7c06a14a 100644
--- a/src/engine/song.h
+++ b/src/engine/song.h
@@ -325,6 +325,7 @@ struct DivSong {
   bool e1e2AlsoTakePriority;
   bool newSegaPCM;
   bool fbPortaPause;
+  bool snDutyReset;
 
   DivOrders orders;
   std::vector<DivInstrument*> ins;
@@ -429,7 +430,8 @@ struct DivSong {
     ignoreDACModeOutsideIntendedChannel(false),
     e1e2AlsoTakePriority(false),
     newSegaPCM(true),
-    fbPortaPause(false) {
+    fbPortaPause(false),
+    snDutyReset(false) {
     for (int i=0; i<32; i++) {
       system[i]=DIV_SYSTEM_NULL;
       systemVol[i]=64;
diff --git a/src/gui/compatFlags.cpp b/src/gui/compatFlags.cpp
index 8d1fd6d1..ccaeeb3f 100644
--- a/src/gui/compatFlags.cpp
+++ b/src/gui/compatFlags.cpp
@@ -117,6 +117,10 @@ void FurnaceGUI::drawCompatFlags() {
     if (ImGui::IsItemHovered()) {
       ImGui::SetTooltip("does this make any sense by now?");
     }
+    ImGui::Checkbox("SN76489 duty macro always resets phase",&e->song.snDutyReset);
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("when enabled, duty macro will always reset phase, even if its value hasn't changed.");
+    }
 
     ImGui::Text("Loop modality:");
     if (ImGui::RadioButton("Reset channels",e->song.loopModality==0)) {

From 52e35fdf049ac9975f297341fcf363a85e57c1e6 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 18:17:05 -0500
Subject: [PATCH 29/46] huh? TODO: fix this

---
 src/engine/platform/genesis.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 61fffcb8..0e8c5954 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -395,7 +395,7 @@ void DivPlatformGenesis::tick(bool sysTick) {
     if (i==2 && extMode) continue;
     if (chan[i].freqChanged) {
       chan[i].freq=((chan[i].baseFreq&0xf800)|parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false,4))+chan[i].std.pitch.val;
-      if (chan[i].freq>65535) chan[i].freq=65535;
+      if (chan[i].freq>0x3fff) chan[i].freq=0x3fff;
       int freqt=chan[i].freq;
       immWrite(chanOffs[i]+ADDR_FREQH,freqt>>8);
       immWrite(chanOffs[i]+ADDR_FREQ,freqt&0xff);

From c84ff399d9f649776c382a6603e1f5ac954d8cd9 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 24 Apr 2022 22:45:59 -0500
Subject: [PATCH 30/46] YM2612: fix negative octaves

---
 src/engine/dispatch.h |  3 ++-
 src/engine/engine.cpp | 11 +++++++++++
 src/engine/engine.h   |  3 +++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/engine/dispatch.h b/src/engine/dispatch.h
index b358c464..bd3b19a6 100644
--- a/src/engine/dispatch.h
+++ b/src/engine/dispatch.h
@@ -426,7 +426,8 @@ class DivDispatch {
 #define NOTE_PERIODIC(x) round(parent->calcBaseFreq(chipClock,CHIP_DIVIDER,x,true))
 #define NOTE_PERIODIC_NOROUND(x) parent->calcBaseFreq(chipClock,CHIP_DIVIDER,x,true)
 #define NOTE_FREQUENCY(x) parent->calcBaseFreq(chipClock,CHIP_FREQBASE,x,false)
-#define NOTE_FNUM_BLOCK(x,bits) ((((int)parent->calcBaseFreq(chipClock,CHIP_FREQBASE,(x)%12,false))&((1<<bits)-1))|((MAX(x,0)/12)<<bits))
+
+#define NOTE_FNUM_BLOCK(x,bits) parent->calcBaseFreqFNumBlock(chipClock,CHIP_FREQBASE,x,bits)
 
 #define COLOR_NTSC (315000000.0/88.0)
 #define COLOR_PAL (283.75*15625.0+25.0)
diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 905ba8aa..2ebbd2fd 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -887,6 +887,17 @@ double DivEngine::calcBaseFreq(double clock, double divider, int note, bool peri
          base*(divider/clock);
 }
 
+unsigned short DivEngine::calcBaseFreqFNumBlock(double clock, double divider, int note, int bits) {
+  int bf=calcBaseFreq(clock,divider,note,false);
+  int block=note/12;
+  if (block<0) block=0;
+  if (block>7) block=7;
+  bf>>=block;
+  if (bf<0) bf=0;
+  if (bf>((1<<bits)-1)) bf=(1<<bits)-1;
+  return bf|(block<<bits);
+}
+
 int DivEngine::calcFreq(int base, int pitch, bool period, int octave) {
   if (song.linearPitch) {
     // global pitch multiplier
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 3bd1db3d..57acf970 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -367,6 +367,9 @@ class DivEngine {
     // calculate base frequency/period
     double calcBaseFreq(double clock, double divider, int note, bool period);
 
+    // calculate base frequency in f-num/block format
+    unsigned short calcBaseFreqFNumBlock(double clock, double divider, int note, int bits);
+
     // calculate frequency/period
     int calcFreq(int base, int pitch, bool period=false, int octave=0);
 

From 832df58929b1f01a2bf3150f366c9d9eb3aaf823 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 01:24:42 -0500
Subject: [PATCH 31/46] YM2612: fix several sample bugs

---
 src/engine/engine.cpp              | 10 ++++-
 src/engine/platform/genesis.cpp    | 69 +++++++++++++++++++++++-------
 src/engine/platform/genesisext.cpp | 14 +++++-
 3 files changed, 74 insertions(+), 19 deletions(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 2ebbd2fd..3bfcb54c 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -894,7 +894,15 @@ unsigned short DivEngine::calcBaseFreqFNumBlock(double clock, double divider, in
   if (block>7) block=7;
   bf>>=block;
   if (bf<0) bf=0;
-  if (bf>((1<<bits)-1)) bf=(1<<bits)-1;
+  if (bf>1288) { // apparently octave boundary
+    while (block<7) {
+      bf>>=1;
+      block++;
+    }
+    if (bf>((1<<bits)-1)) {
+      bf=(1<<bits)-1;
+    }
+  }
   return bf|(block<<bits);
 }
 
diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 0e8c5954..324a66e0 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -87,8 +87,8 @@ void DivPlatformGenesis::acquire_nuked(short* bufL, short* bufR, size_t start, s
 
   for (size_t h=start; h<start+len; h++) {
     if (dacMode && dacSample!=-1) {
-      dacPeriod-=6;
-      if (dacPeriod<1) {
+      dacPeriod+=dacRate;
+      if (dacPeriod>=rate) {
         DivSample* s=parent->getSample(dacSample);
         if (s->samples>0) {
           if (!isMuted[5]) {
@@ -106,7 +106,7 @@ void DivPlatformGenesis::acquire_nuked(short* bufL, short* bufR, size_t start, s
               }
             }
           }
-          dacPeriod+=MAX(40,dacRate);
+          dacPeriod-=rate;
         } else {
           dacSample=-1;
         }
@@ -156,8 +156,8 @@ void DivPlatformGenesis::acquire_ymfm(short* bufL, short* bufR, size_t start, si
 
   for (size_t h=start; h<start+len; h++) {
     if (dacMode && dacSample!=-1) {
-      dacPeriod-=24;
-      if (dacPeriod<1) {
+      dacPeriod+=dacRate;
+      if (dacPeriod>=rate) {
         DivSample* s=parent->getSample(dacSample);
         if (s->samples>0) {
           if (!isMuted[5]) {
@@ -175,7 +175,7 @@ void DivPlatformGenesis::acquire_ymfm(short* bufL, short* bufR, size_t start, si
               }
             }
           }
-          dacPeriod+=MAX(40,dacRate);
+          dacPeriod-=rate;
         } else {
           dacSample=-1;
         }
@@ -394,11 +394,20 @@ void DivPlatformGenesis::tick(bool sysTick) {
   for (int i=0; i<6; i++) {
     if (i==2 && extMode) continue;
     if (chan[i].freqChanged) {
-      chan[i].freq=((chan[i].baseFreq&0xf800)|parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false,4))+chan[i].std.pitch.val;
+      int fNum=parent->calcFreq(chan[i].baseFreq&0x7ff,chan[i].pitch,false,4)+chan[i].std.pitch.val;
+      int block=(chan[i].baseFreq&0xf800)>>11;
+      if (fNum<0) fNum=0;
+      if (fNum>2047) {
+        while (block<7) {
+          fNum>>=1;
+          block++;
+        }
+        if (fNum>2047) fNum=2047;
+      }
+      chan[i].freq=(block<<11)|fNum;
       if (chan[i].freq>0x3fff) chan[i].freq=0x3fff;
-      int freqt=chan[i].freq;
-      immWrite(chanOffs[i]+ADDR_FREQH,freqt>>8);
-      immWrite(chanOffs[i]+ADDR_FREQ,freqt&0xff);
+      immWrite(chanOffs[i]+ADDR_FREQH,chan[i].freq>>8);
+      immWrite(chanOffs[i]+ADDR_FREQ,chan[i].freq&0xff);
       if (chan[i].furnaceDac && dacMode) {
         double off=1.0;
         if (dacSample>=0 && dacSample<parent->song.sampleLen) {
@@ -406,12 +415,13 @@ void DivPlatformGenesis::tick(bool sysTick) {
           if (s->centerRate<1) {
             off=1.0;
           } else {
-            off=8363.0/(double)s->centerRate;
+            off=(double)s->centerRate/8363.0;
           }
         }
-        dacRate=(1280000*1.25*off)/MAX(1,chan[i].baseFreq);
+        chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,false,4)+chan[i].std.pitch.val;;
+        dacRate=chan[i].freq*off;
         if (dacRate<1) dacRate=1;
-        if (dumpWrites) addWrite(0xffff0001,1280000/dacRate);
+        if (dumpWrites) addWrite(0xffff0001,dacRate);
       }
       chan[i].freqChanged=false;
     }
@@ -468,7 +478,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
           dacPos=0;
           dacPeriod=0;
           if (c.value!=DIV_NOTE_NULL) {
-            chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
+            chan[c.chan].baseFreq=parent->calcBaseFreq(1,1,c.value,false);
             chan[c.chan].freqChanged=true;
           }
           chan[c.chan].furnaceDac=true;
@@ -487,7 +497,7 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
           }
           dacPos=0;
           dacPeriod=0;
-          dacRate=1280000/MAX(1,parent->getSample(dacSample)->rate);
+          dacRate=MAX(1,parent->getSample(dacSample)->rate);
           if (dumpWrites) addWrite(0xffff0001,parent->getSample(dacSample)->rate);
           chan[c.chan].furnaceDac=false;
         }
@@ -615,6 +625,29 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       break;
     }
     case DIV_CMD_NOTE_PORTA: {
+      if (c.chan==5 && chan[c.chan].furnaceDac) {
+        int destFreq=parent->calcBaseFreq(1,1,c.value2,false);
+        bool return2=false;
+        if (destFreq>chan[c.chan].baseFreq) {
+          chan[c.chan].baseFreq+=c.value*16;
+          if (chan[c.chan].baseFreq>=destFreq) {
+            chan[c.chan].baseFreq=destFreq;
+            return2=true;
+          }
+        } else {
+          chan[c.chan].baseFreq-=c.value*16;
+          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;
+      }
       int destFreq=NOTE_FNUM_BLOCK(c.value2,11);
       int newFreq;
       bool return2=false;
@@ -669,7 +702,11 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       }
       break;
     case DIV_CMD_LEGATO: {
-      chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
+      if (c.chan==5 && chan[c.chan].furnaceDac) {
+        chan[c.chan].baseFreq=parent->calcBaseFreq(1,1,c.value,false);
+      } else {
+        chan[c.chan].baseFreq=NOTE_FNUM_BLOCK(c.value,11);
+      }
       chan[c.chan].note=c.value;
       chan[c.chan].freqChanged=true;
       break;
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index 479e4242..f146e2fc 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -307,8 +307,18 @@ void DivPlatformGenesisExt::tick(bool sysTick) {
   unsigned char writeMask=2;
   if (extMode) for (int i=0; i<4; i++) {
     if (opChan[i].freqChanged) {
-      opChan[i].freq=(opChan[i].baseFreq&0xf800)|parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch,false,4);
-      if (chan[i].freq>65535) chan[i].freq=65535;
+      int fNum=parent->calcFreq(opChan[i].baseFreq&0x7ff,opChan[i].pitch,false,4)+opChan[i].std.pitch.val;
+      int block=(opChan[i].baseFreq&0xf800)>>11;
+      if (fNum<0) fNum=0;
+      if (fNum>2047) {
+        while (block<7) {
+          fNum>>=1;
+          block++;
+        }
+        if (fNum>2047) fNum=2047;
+      }
+      opChan[i].freq=(block<<11)|fNum;
+      if (opChan[i].freq>0x3fff) opChan[i].freq=0x3fff;
       immWrite(opChanOffsH[i],opChan[i].freq>>8);
       immWrite(opChanOffsL[i],opChan[i].freq&0xff);
     }

From bcade6931a45163096c59c04f4f38223d8600f0a Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 01:42:26 -0500
Subject: [PATCH 32/46] YM2612: allow for DAC rate higher than 32KHz

issue #391
---
 src/engine/platform/genesis.cpp | 26 ++++++++++++++++++++++----
 src/engine/platform/genesis.h   |  2 ++
 2 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index 324a66e0..f2203fc3 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -86,14 +86,22 @@ void DivPlatformGenesis::acquire_nuked(short* bufL, short* bufR, size_t start, s
   static int os[2];
 
   for (size_t h=start; h<start+len; h++) {
+    if (!dacReady) {
+      dacDelay+=32000;
+      if (dacDelay>=rate) {
+        dacDelay-=rate;
+        dacReady=true;
+      }
+    }
     if (dacMode && dacSample!=-1) {
       dacPeriod+=dacRate;
       if (dacPeriod>=rate) {
         DivSample* s=parent->getSample(dacSample);
         if (s->samples>0) {
           if (!isMuted[5]) {
-            if (writes.size()<16) {
+            if (dacReady && writes.size()<16) {
               urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+              dacReady=false;
             }
           }
           if (++dacPos>=s->samples) {
@@ -106,7 +114,7 @@ void DivPlatformGenesis::acquire_nuked(short* bufL, short* bufR, size_t start, s
               }
             }
           }
-          dacPeriod-=rate;
+          while (dacPeriod>=rate) dacPeriod-=rate;
         } else {
           dacSample=-1;
         }
@@ -155,14 +163,22 @@ void DivPlatformGenesis::acquire_ymfm(short* bufL, short* bufR, size_t start, si
   static int os[2];
 
   for (size_t h=start; h<start+len; h++) {
+    if (!dacReady) {
+      dacDelay+=32000;
+      if (dacDelay>=rate) {
+        dacDelay-=rate;
+        dacReady=true;
+      }
+    }
     if (dacMode && dacSample!=-1) {
       dacPeriod+=dacRate;
       if (dacPeriod>=rate) {
         DivSample* s=parent->getSample(dacSample);
         if (s->samples>0) {
           if (!isMuted[5]) {
-            if (writes.size()<16) {
+            if (dacReady && writes.size()<16) {
               urgentWrite(0x2a,(unsigned char)s->data8[dacPos]+0x80);
+              dacReady=false;
             }
           }
           if (++dacPos>=s->samples) {
@@ -175,7 +191,7 @@ void DivPlatformGenesis::acquire_ymfm(short* bufL, short* bufR, size_t start, si
               }
             }
           }
-          dacPeriod-=rate;
+          while (dacPeriod>=rate) dacPeriod-=rate;
         } else {
           dacSample=-1;
         }
@@ -858,6 +874,8 @@ void DivPlatformGenesis::reset() {
   dacPeriod=0;
   dacPos=0;
   dacRate=0;
+  dacDelay=0;
+  dacReady=true;
   dacSample=-1;
   sampleBank=0;
   lfoValue=8;
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index b9430306..aa7659fa 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -85,6 +85,8 @@ class DivPlatformGenesis: public DivDispatch {
     int dacRate;
     unsigned int dacPos;
     int dacSample;
+    int dacDelay;
+    bool dacReady;
     unsigned char sampleBank;
     unsigned char lfoValue;
 

From ed6820ac46df214cef057ae666bfe975b145263d Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 11:23:44 -0500
Subject: [PATCH 33/46] GUI: fix cursor going out of bounds on paste

---
 src/gui/editing.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/gui/editing.cpp b/src/gui/editing.cpp
index 106ec61b..e5874f91 100644
--- a/src/gui/editing.cpp
+++ b/src/gui/editing.cpp
@@ -554,6 +554,7 @@ void FurnaceGUI::doPaste(PasteMode mode) {
   }
   if (settings.cursorPastePos) {
     cursor.y=j;
+    if (cursor.y>=e->song.patLen) cursor.y=e->song.patLen-1;
     updateScroll(cursor.y);
   }
 
@@ -1003,4 +1004,4 @@ void FurnaceGUI::doRedo() {
   }
 
   redoHist.pop_back();
-}
\ No newline at end of file
+}

From 17cf657f6acb3aa323c6267def47cec0bb6cacfd Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 11:52:05 -0500
Subject: [PATCH 34/46] one more pitch calc fix

---
 src/engine/engine.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 3bfcb54c..c56eff9c 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -894,7 +894,12 @@ unsigned short DivEngine::calcBaseFreqFNumBlock(double clock, double divider, in
   if (block>7) block=7;
   bf>>=block;
   if (bf<0) bf=0;
-  if (bf>1288) { // apparently octave boundary
+  // octave boundaries
+  while (bf>0 && bf<644 && block>0) {
+    bf<<=1;
+    block--;
+  }
+  if (bf>1288) {
     while (block<7) {
       bf>>=1;
       block++;

From 1b97d3912bcd7872da78ac8b47779ee54c821c01 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 11:59:02 -0500
Subject: [PATCH 35/46] YM2612: hopefully the final pitch slide fix

---
 src/engine/platform/genesis.cpp    | 6 +++---
 src/engine/platform/genesisext.cpp | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/engine/platform/genesis.cpp b/src/engine/platform/genesis.cpp
index f2203fc3..72dc9c0f 100644
--- a/src/engine/platform/genesis.cpp
+++ b/src/engine/platform/genesis.cpp
@@ -434,7 +434,7 @@ void DivPlatformGenesis::tick(bool sysTick) {
             off=(double)s->centerRate/8363.0;
           }
         }
-        chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,false,4)+chan[i].std.pitch.val;;
+        chan[i].freq=parent->calcFreq(chan[i].baseFreq,chan[i].pitch,false,4)+chan[i].std.pitch.val;
         dacRate=chan[i].freq*off;
         if (dacRate<1) dacRate=1;
         if (dumpWrites) addWrite(0xffff0001,dacRate);
@@ -686,12 +686,12 @@ int DivPlatformGenesis::dispatch(DivCommand c) {
       // check for octave boundary
       // what the heck!
       if (!chan[c.chan].portaPause) {
-        if ((newFreq&0x7ff)>1288) {
+        if ((newFreq&0x7ff)>1288 && (newFreq&0xf800)<0x3800) {
           chan[c.chan].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
           chan[c.chan].portaPause=true;
           break;
         }
-        if ((newFreq&0x7ff)<644) {
+        if ((newFreq&0x7ff)<644 && (newFreq&0xf800)>0) {
           chan[c.chan].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
           chan[c.chan].portaPause=true;
           break;
diff --git a/src/engine/platform/genesisext.cpp b/src/engine/platform/genesisext.cpp
index f146e2fc..59b77587 100644
--- a/src/engine/platform/genesisext.cpp
+++ b/src/engine/platform/genesisext.cpp
@@ -148,7 +148,7 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
       }
       // what the heck!
       if (!opChan[ch].portaPause) {
-        if ((newFreq&0x7ff)>1288) {
+        if ((newFreq&0x7ff)>1288 && (newFreq&0xf800)<0x3800) {
           if (parent->song.fbPortaPause) {
             opChan[ch].portaPauseFreq=(644)|((newFreq+0x800)&0xf800);
             opChan[ch].portaPause=true;
@@ -157,7 +157,7 @@ int DivPlatformGenesisExt::dispatch(DivCommand c) {
             newFreq=(newFreq>>1)|((newFreq+0x800)&0xf800);
           }
         }
-        if ((newFreq&0x7ff)<644) {
+        if ((newFreq&0x7ff)<644 && (newFreq&0xf800)>0) {
           if (parent->song.fbPortaPause) {
             opChan[ch].portaPauseFreq=newFreq=(1287)|((newFreq-0x800)&0xf800);
             opChan[ch].portaPause=true;

From 7b79c3225823be4a21508543c016d0bcbd632168 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 14:58:58 -0500
Subject: [PATCH 36/46] increase range of arp macro to 120

---
 src/gui/insEdit.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index 7879d966..a3368e92 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -2836,7 +2836,7 @@ void FurnaceGUI::drawInsEdit() {
             if (volMax>0) {
               NORMAL_MACRO(ins->std.volMacro,volMin,volMax,"vol",volumeLabel,160,ins->std.volMacro.open,false,NULL,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_VOLUME],mmlString[0],volMin,volMax,NULL,false);
             }
-            NORMAL_MACRO(ins->std.arpMacro,arpMacroScroll,arpMacroScroll+24,"arp","Arpeggio",160,ins->std.arpMacro.open,false,NULL,true,&arpMacroScroll,(arpMode?-60:-80),70,0,0,true,1,macroAbsoluteMode,uiColors[GUI_COLOR_MACRO_PITCH],mmlString[1],-92,94,(ins->std.arpMacro.mode?(&macroHoverNote):NULL),true);
+            NORMAL_MACRO(ins->std.arpMacro,arpMacroScroll,arpMacroScroll+24,"arp","Arpeggio",160,ins->std.arpMacro.open,false,NULL,true,&arpMacroScroll,(arpMode?-60:-120),120,0,0,true,1,macroAbsoluteMode,uiColors[GUI_COLOR_MACRO_PITCH],mmlString[1],-120,120,(ins->std.arpMacro.mode?(&macroHoverNote):NULL),true);
             if (dutyMax>0) {
               if (ins->type==DIV_INS_MIKEY) {
                 NORMAL_MACRO(ins->std.dutyMacro,0,dutyMax,"duty",dutyLabel,160,ins->std.dutyMacro.open,true,mikeyFeedbackBits,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[2],0,dutyMax,NULL,false);

From f3f92b80352f4226a179b31860cee488ddbe911a Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 15:07:36 -0500
Subject: [PATCH 37/46] GUI: deprecate compat rate

---
 src/gui/sampleEdit.cpp | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/src/gui/sampleEdit.cpp b/src/gui/sampleEdit.cpp
index 802e10bc..53379c99 100644
--- a/src/gui/sampleEdit.cpp
+++ b/src/gui/sampleEdit.cpp
@@ -74,15 +74,6 @@ void FurnaceGUI::drawSampleEdit() {
             ImGui::EndCombo();
           }
 
-          ImGui::TableNextColumn();
-          ImGui::Text("Rate (Hz)");
-          ImGui::SameLine();
-          ImGui::SetNextItemWidth(ImGui::GetContentRegionAvail().x);
-          if (ImGui::InputInt("##SampleRate",&sample->rate,10,200)) { MARK_MODIFIED
-            if (sample->rate<100) sample->rate=100;
-            if (sample->rate>96000) sample->rate=96000;
-          }
-
           ImGui::TableNextColumn();
           ImGui::Text("C-4 (Hz)");
           ImGui::SameLine();
@@ -92,6 +83,15 @@ void FurnaceGUI::drawSampleEdit() {
             if (sample->centerRate>65535) sample->centerRate=65535;
           }
 
+          ImGui::TableNextColumn();
+          ImGui::Text("Compat Rate");
+          ImGui::SameLine();
+          ImGui::SetNextItemWidth(ImGui::GetContentRegionAvail().x);
+          if (ImGui::InputInt("##SampleRate",&sample->rate,10,200)) { MARK_MODIFIED
+            if (sample->rate<100) sample->rate=100;
+            if (sample->rate>96000) sample->rate=96000;
+          }
+
           ImGui::TableNextColumn();
           bool doLoop=(sample->loopStart>=0);
           if (ImGui::Checkbox("Loop",&doLoop)) { MARK_MODIFIED
@@ -587,16 +587,6 @@ void FurnaceGUI::drawSampleEdit() {
             ImGui::EndCombo();
           }
 
-          ImGui::TableNextColumn();
-          ImGui::Text("Rate (Hz)");
-          ImGui::SameLine();
-          ImGui::SetNextItemWidth(ImGui::GetContentRegionAvail().x);
-          if (ImGui::InputInt("##SampleRate",&sample->rate,10,200)) { MARK_MODIFIED
-            if (sample->rate<100) sample->rate=100;
-            if (sample->rate>96000) sample->rate=96000;
-          }
-
-          ImGui::TableNextRow();
           ImGui::TableNextColumn();
           ImGui::Text("C-4 (Hz)");
           ImGui::SameLine();
@@ -606,6 +596,16 @@ void FurnaceGUI::drawSampleEdit() {
             if (sample->centerRate>65535) sample->centerRate=65535;
           }
 
+          ImGui::TableNextRow();
+          ImGui::TableNextColumn();
+          ImGui::Text("Compat Rate");
+          ImGui::SameLine();
+          ImGui::SetNextItemWidth(ImGui::GetContentRegionAvail().x);
+          if (ImGui::InputInt("##SampleRate",&sample->rate,10,200)) { MARK_MODIFIED
+            if (sample->rate<100) sample->rate=100;
+            if (sample->rate>96000) sample->rate=96000;
+          }
+
           ImGui::TableNextColumn();
           bool doLoop=(sample->loopStart>=0);
           if (ImGui::Checkbox("Loop",&doLoop)) { MARK_MODIFIED

From 5821135b38c916ffdb088fedc06836e3476e5057 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 15:54:31 -0500
Subject: [PATCH 38/46] don't return 1 on -help and -version

fixes #385
---
 src/main.cpp   | 67 ++++++++++++++++++++++++++++----------------------
 src/ta-utils.h | 10 ++++++--
 2 files changed, 46 insertions(+), 31 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index 4a3e9d0e..5db37c30 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -60,7 +60,7 @@ bool displayEngineFailError=false;
 
 std::vector<TAParam> params;
 
-bool pHelp(String) {
+TAParamResult pHelp(String) {
   printf("usage: furnace [params] [filename]\n"
          "you may specify the following parameters:\n");
   for (auto& i: params) {
@@ -70,13 +70,13 @@ bool pHelp(String) {
       printf("  -%s: %s\n",i.name.c_str(),i.desc.c_str());
     }
   }
-  return false;
+  return TA_PARAM_QUIT;
 }
 
-bool pAudio(String val) {
+TAParamResult pAudio(String val) {
   if (outName!="") {
     logE("can't use -audio and -output at the same time.");
-    return false;
+    return TA_PARAM_ERROR;
   }
   if (val=="jack") {
     e.setAudio(DIV_AUDIO_JACK);
@@ -84,12 +84,12 @@ bool pAudio(String val) {
     e.setAudio(DIV_AUDIO_SDL);
   } else {
     logE("invalid value for audio engine! valid values are: jack, sdl.");
-    return false;
+    return TA_PARAM_ERROR;
   }
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pView(String val) {
+TAParamResult pView(String val) {
   if (val=="pattern") {
     e.setView(DIV_STATUS_PATTERN);
   } else if (val=="commands") {
@@ -98,17 +98,17 @@ bool pView(String val) {
     e.setView(DIV_STATUS_NOTHING);
   } else {
     logE("invalid value for view type! valid values are: pattern, commands, nothing.");
-    return false;
+    return TA_PARAM_ERROR;
   }
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pConsole(String val) {
+TAParamResult pConsole(String val) {
   consoleMode=true;
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pLogLevel(String val) {
+TAParamResult pLogLevel(String val) {
   if (val=="trace") {
     logLevel=LOGLEVEL_TRACE;
   } else if (val=="debug") {
@@ -121,12 +121,12 @@ bool pLogLevel(String val) {
     logLevel=LOGLEVEL_ERROR;
   } else {
     logE("invalid value for loglevel! valid values are: trace, debug, info, warning, error.");
-    return false;
+    return TA_PARAM_ERROR;
   }
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pVersion(String) {
+TAParamResult pVersion(String) {
   printf("Furnace version " DIV_VERSION ".\n\n");
   printf("copyright (C) 2021-2022 tildearrow and contributors.\n");
   printf("licensed under the GNU General Public License version 2 or later\n");
@@ -152,10 +152,10 @@ bool pVersion(String) {
   printf("- puNES by FHorse (GPLv2)\n");
   printf("- reSID by Dag Lem (GPLv2)\n");
   printf("- Stella by Stella Team (GPLv2)\n");
-  return false;
+  return TA_PARAM_QUIT;
 }
 
-bool pWarranty(String) {
+TAParamResult pWarranty(String) {
   printf("This program is free software; you can redistribute it and/or\n"
          "modify it under the terms of the GNU General Public License\n"
          "as published by the Free Software Foundation; either version 2\n"
@@ -169,10 +169,10 @@ bool pWarranty(String) {
          "You should have received a copy of the GNU General Public License\n"
          "along with this program; if not, write to the Free Software\n"
          "Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.\n");
-  return false;
+  return TA_PARAM_QUIT;
 }
 
-bool pLoops(String val) {
+TAParamResult pLoops(String val) {
   try {
     int count=std::stoi(val);
     if (count<0) {
@@ -182,12 +182,12 @@ bool pLoops(String val) {
     }
   } catch (std::exception& e) {
     logE("loop count shall be a number.");
-    return false;
+    return TA_PARAM_ERROR;
   }
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pOutMode(String val) {
+TAParamResult pOutMode(String val) {
   if (val=="one") {
     outMode=DIV_EXPORT_MODE_ONE;
   } else if (val=="persys") {
@@ -196,21 +196,21 @@ bool pOutMode(String val) {
     outMode=DIV_EXPORT_MODE_MANY_CHAN;
   } else {
     logE("invalid value for outmode! valid values are: one, persys and perchan.");
-    return false;
+    return TA_PARAM_ERROR;
   }
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pOutput(String val) {
+TAParamResult pOutput(String val) {
   outName=val;
   e.setAudio(DIV_AUDIO_DUMMY);
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
-bool pVGMOut(String val) {
+TAParamResult pVGMOut(String val) {
   vgmOutName=val;
   e.setAudio(DIV_AUDIO_DUMMY);
-  return true;
+  return TA_PARAM_SUCCESS;
 }
 
 bool needsValue(String param) {
@@ -283,7 +283,16 @@ int main(int argc, char** argv) {
       }
       for (size_t j=0; j<params.size(); j++) {
         if (params[j].name==arg || params[j].shortName==arg) {
-          if (!params[j].func(val)) return 1;
+          switch (params[j].func(val)) {
+            case TA_PARAM_ERROR:
+              return 1;
+              break;
+            case TA_PARAM_SUCCESS:
+              break;
+            case TA_PARAM_QUIT:
+              return 0;
+              break;
+          }
           break;
         }
       }
diff --git a/src/ta-utils.h b/src/ta-utils.h
index 014f65f6..3a619248 100644
--- a/src/ta-utils.h
+++ b/src/ta-utils.h
@@ -43,14 +43,20 @@ typedef std::string String;
 
 typedef std::wstring WString;
 
+enum TAParamResult {
+  TA_PARAM_ERROR=0,
+  TA_PARAM_SUCCESS,
+  TA_PARAM_QUIT
+};
+
 struct TAParam {
   String shortName;
   String name;
   String valName;
   String desc;
   bool value;
-  bool (*func)(String);
-  TAParam(const String& sn, const String& n, bool v, bool (*f)(String), const String& vn, const String& d):
+  TAParamResult (*func)(String);
+  TAParam(const String& sn, const String& n, bool v, TAParamResult (*f)(String), const String& vn, const String& d):
     shortName(sn),
     name(n),
     valName(vn),

From 8ba2787160b75137fb85e919d7197571168c6158 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 16:46:38 -0500
Subject: [PATCH 39/46] GUI: add two ImGui settings

---
 src/gui/gui.h        |  4 ++++
 src/gui/settings.cpp | 24 ++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/src/gui/gui.h b/src/gui/gui.h
index 8c850fd0..98a86112 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -842,6 +842,8 @@ class FurnaceGUI {
     int notePreviewBehavior;
     int powerSave;
     int absorbInsInput;
+    int eventDelay;
+    int moveWindowTitle;
     unsigned int maxUndoSteps;
     String mainFontPath;
     String patFontPath;
@@ -917,6 +919,8 @@ class FurnaceGUI {
       notePreviewBehavior(1),
       powerSave(1),
       absorbInsInput(0),
+      eventDelay(0),
+      moveWindowTitle(0),
       maxUndoSteps(100),
       mainFontPath(""),
       patFontPath(""),
diff --git a/src/gui/settings.cpp b/src/gui/settings.cpp
index c7a23511..61493722 100644
--- a/src/gui/settings.cpp
+++ b/src/gui/settings.cpp
@@ -313,6 +313,21 @@ void FurnaceGUI::drawSettings() {
           settings.sysFileDialog=sysFileDialogB;
         }
 
+        bool moveWindowTitleB=settings.moveWindowTitle;
+        if (ImGui::Checkbox("Only allow window movement when clicking on title bar",&moveWindowTitleB)) {
+          settings.moveWindowTitle=moveWindowTitleB;
+          applyUISettings(false);
+        }
+
+        bool eventDelayB=settings.eventDelay;
+        if (ImGui::Checkbox("Enable event delay",&eventDelayB)) {
+          settings.eventDelay=eventDelayB;
+          applyUISettings(false);
+        }
+        if (ImGui::IsItemHovered()) {
+          ImGui::SetTooltip("may cause issues with high-polling-rate mice when previewing notes.");
+        }
+
         bool powerSaveB=settings.powerSave;
         if (ImGui::Checkbox("Power-saving mode",&powerSaveB)) {
           settings.powerSave=powerSaveB;
@@ -1651,6 +1666,8 @@ void FurnaceGUI::syncSettings() {
   settings.notePreviewBehavior=e->getConfInt("notePreviewBehavior",1);
   settings.powerSave=e->getConfInt("powerSave",POWER_SAVE_DEFAULT);
   settings.absorbInsInput=e->getConfInt("absorbInsInput",0);
+  settings.eventDelay=e->getConfInt("eventDelay",0);
+  settings.moveWindowTitle=e->getConfInt("moveWindowTitle",0);
 
   clampSetting(settings.mainFontSize,2,96);
   clampSetting(settings.patFontSize,2,96);
@@ -1715,6 +1732,8 @@ void FurnaceGUI::syncSettings() {
   clampSetting(settings.notePreviewBehavior,0,3);
   clampSetting(settings.powerSave,0,1);
   clampSetting(settings.absorbInsInput,0,1);
+  clampSetting(settings.eventDelay,0,1);
+  clampSetting(settings.moveWindowTitle,0,1);
 
   // keybinds
   for (int i=0; i<GUI_ACTION_MAX; i++) {
@@ -1806,6 +1825,8 @@ void FurnaceGUI::commitSettings() {
   e->setConf("notePreviewBehavior",settings.notePreviewBehavior);
   e->setConf("powerSave",settings.powerSave);
   e->setConf("absorbInsInput",settings.absorbInsInput);
+  e->setConf("eventDelay",settings.eventDelay);
+  e->setConf("moveWindowTitle",settings.moveWindowTitle);
 
   // colors
   for (int i=0; i<GUI_COLOR_MAX; i++) {
@@ -2317,6 +2338,9 @@ void FurnaceGUI::applyUISettings(bool updateFonts) {
 
   ImGui::GetStyle()=sty;
 
+  ImGui::GetIO().ConfigInputTrickleEventQueue=settings.eventDelay;
+  ImGui::GetIO().ConfigWindowsMoveFromTitleBarOnly=settings.moveWindowTitle;
+
   for (int i=0; i<256; i++) {
     ImVec4& base=uiColors[GUI_COLOR_PATTERN_EFFECT_PITCH];
     pitchGrad[i]=ImGui::GetColorU32(ImVec4(base.x,base.y,base.z,((float)i/255.0f)*base.w));

From 2a952b1a664da75e195922f57f44de85f4ca6300 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 17:55:48 -0500
Subject: [PATCH 40/46] dev87 - C64 changes

issue #335
---
 papers/format.md            |  3 +++
 src/engine/engine.h         |  4 ++--
 src/engine/fileOps.cpp      | 30 ++++++++++++++++++++++++++----
 src/engine/fileOpsIns.cpp   | 10 ++++++++++
 src/engine/instrument.cpp   |  8 ++++++++
 src/engine/platform/c64.cpp |  4 ++--
 src/gui/insEdit.cpp         | 12 ++++++------
 7 files changed, 57 insertions(+), 14 deletions(-)

diff --git a/papers/format.md b/papers/format.md
index 207b232a..083fd766 100644
--- a/papers/format.md
+++ b/papers/format.md
@@ -29,6 +29,7 @@ furthermore, an `or reserved` indicates this field is always present, but is res
 
 the format versions are:
 
+- 87: Furnace dev87
 - 86: Furnace dev86
 - 85: Furnace dev85
 - 84: Furnace dev84
@@ -423,9 +424,11 @@ size | description
   1  | reserved (>=17) or duty macro height (>=15) or reserved
   1  | reserved (>=17) or wave macro height (>=15) or reserved
  4?? | volume macro
+     | - before version 87, if this is the C64 relative cutoff macro, its values were stored offset by 18.
  4?? | arp macro
      | - before version 31, this macro's values were stored offset by 12.
  4?? | duty macro
+     | - before version 87, if this is the C64 relative duty macro, its values were stored offset by 12.
  4?? | wave macro
  4?? | pitch macro (>=17)
  4?? | extra 1 macro (>=17)
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 57acf970..212bf422 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -43,8 +43,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev86"
-#define DIV_ENGINE_VERSION 86
+#define DIV_VERSION "dev87"
+#define DIV_ENGINE_VERSION 87
 
 // for imports
 #define DIV_VERSION_MOD 0xff01
diff --git a/src/engine/fileOps.cpp b/src/engine/fileOps.cpp
index 38b33502..ca2f2d10 100644
--- a/src/engine/fileOps.cpp
+++ b/src/engine/fileOps.cpp
@@ -501,9 +501,9 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
           } else {
             ins->std.dutyMacro.val[j]=reader.readI();
           }
-          if ((ds.system[0]==DIV_SYSTEM_C64_8580 || ds.system[0]==DIV_SYSTEM_C64_6581) && ins->std.dutyMacro.val[j]>24) {
+          /*if ((ds.system[0]==DIV_SYSTEM_C64_8580 || ds.system[0]==DIV_SYSTEM_C64_6581) && ins->std.dutyMacro.val[j]>24) {
             ins->std.dutyMacro.val[j]=24;
-          }
+          }*/
         }
         if (ins->std.dutyMacro.len>0) {
           ins->std.dutyMacro.open=true;
@@ -556,6 +556,16 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
           ins->c64.bp=reader.readC();
           ins->c64.lp=reader.readC();
           ins->c64.ch3off=reader.readC();
+
+          // weird storage
+          if (ins->c64.volIsCutoff) {
+            for (int j=0; j<ins->std.volMacro.len; j++) {
+              ins->std.volMacro.val[j]-=18;
+            }
+          }
+          for (int j=0; j<ins->std.dutyMacro.len; j++) {
+            ins->std.dutyMacro.val[j]-=12;
+          }
         }
 
         if (ds.system[0]==DIV_SYSTEM_GB && ds.version>0x11) {
@@ -2609,7 +2619,13 @@ SafeWriter* DivEngine::saveDMF(unsigned char version) {
     } else { // STD
       if (sys!=DIV_SYSTEM_GB) {
         w->writeC(i->std.volMacro.len);
-        w->write(i->std.volMacro.val,4*i->std.volMacro.len);
+        if ((sys==DIV_SYSTEM_C64_6581 || sys==DIV_SYSTEM_C64_8580) && i->c64.volIsCutoff) {
+          for (int j=0; j<i->std.volMacro.len; j++) {
+            w->writeI(i->std.volMacro.val[j]+18);
+          }
+        } else {
+          w->write(i->std.volMacro.val,4*i->std.volMacro.len);
+        }
         if (i->std.volMacro.len>0) {
           w->writeC(i->std.volMacro.loop);
         }
@@ -2629,7 +2645,13 @@ SafeWriter* DivEngine::saveDMF(unsigned char version) {
       w->writeC(i->std.arpMacro.mode);
 
       w->writeC(i->std.dutyMacro.len);
-      w->write(i->std.dutyMacro.val,4*i->std.dutyMacro.len);
+      if (sys==DIV_SYSTEM_C64_6581 || sys==DIV_SYSTEM_C64_8580) {
+        for (int j=0; j<i->std.dutyMacro.len; j++) {
+          w->writeI(i->std.dutyMacro.val[j]+12);
+        }
+      } else {
+        w->write(i->std.dutyMacro.val,4*i->std.dutyMacro.len);
+      }
       if (i->std.dutyMacro.len>0) {
         w->writeC(i->std.dutyMacro.loop);
       }
diff --git a/src/engine/fileOpsIns.cpp b/src/engine/fileOpsIns.cpp
index e080b779..1173d59a 100644
--- a/src/engine/fileOpsIns.cpp
+++ b/src/engine/fileOpsIns.cpp
@@ -345,6 +345,16 @@ void DivEngine::loadDMP(SafeReader& reader, std::vector<DivInstrument*>& ret, St
         ins->c64.bp=reader.readC();
         ins->c64.lp=reader.readC();
         ins->c64.ch3off=reader.readC();
+
+        // weird storage
+        if (ins->c64.volIsCutoff) {
+          for (int j=0; j<ins->std.volMacro.len; j++) {
+            ins->std.volMacro.val[j]-=18;
+          }
+        }
+        for (int j=0; j<ins->std.dutyMacro.len; j++) {
+          ins->std.dutyMacro.val[j]-=12;
+        }
       }
       if (ins->type==DIV_INS_GB) {
         ins->gb.envVol=reader.readC();
diff --git a/src/engine/instrument.cpp b/src/engine/instrument.cpp
index 273af9bf..d5061e0b 100644
--- a/src/engine/instrument.cpp
+++ b/src/engine/instrument.cpp
@@ -639,6 +639,14 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
       std.arpMacro.val[j]-=12;
     }
   }
+  if (type==DIV_INS_C64 && version<87) {
+    if (c64.volIsCutoff && !c64.filterIsAbs) for (int j=0; j<std.volMacro.len; j++) {
+      std.volMacro.val[j]-=18;
+    }
+    if (!c64.dutyIsAbs) for (int j=0; j<std.dutyMacro.len; j++) {
+      std.dutyMacro.val[j]-=12;
+    }
+  }
   if (version>=17) {
     reader.read(std.pitchMacro.val,4*std.pitchMacro.len);
     reader.read(std.ex1Macro.val,4*std.ex1Macro.len);
diff --git a/src/engine/platform/c64.cpp b/src/engine/platform/c64.cpp
index 604dcfe3..79cfb42b 100644
--- a/src/engine/platform/c64.cpp
+++ b/src/engine/platform/c64.cpp
@@ -131,7 +131,7 @@ void DivPlatformC64::tick(bool sysTick) {
         if (ins->c64.filterIsAbs) {
           filtCut=MIN(2047,chan[i].std.vol.val);
         } else {
-          filtCut-=((signed char)chan[i].std.vol.val-18)*7;
+          filtCut-=((signed char)chan[i].std.vol.val)*7;
           if (filtCut>2047) filtCut=2047;
           if (filtCut<0) filtCut=0;
         }
@@ -161,7 +161,7 @@ void DivPlatformC64::tick(bool sysTick) {
       if (ins->c64.dutyIsAbs) {
         chan[i].duty=chan[i].std.duty.val;
       } else {
-        chan[i].duty-=((signed char)chan[i].std.duty.val-12)*4;
+        chan[i].duty-=((signed char)chan[i].std.duty.val)*4;
       }
       rWrite(i*7+2,chan[i].duty&0xff);
       rWrite(i*7+3,chan[i].duty>>8);
diff --git a/src/gui/insEdit.cpp b/src/gui/insEdit.cpp
index a3368e92..77781f9d 100644
--- a/src/gui/insEdit.cpp
+++ b/src/gui/insEdit.cpp
@@ -2687,8 +2687,8 @@ void FurnaceGUI::drawInsEdit() {
               if (ins->c64.filterIsAbs) {
                 volMax=2047;
               } else {
-                volMin=-18;
-                volMax=18;
+                volMin=-64;
+                volMax=64;
               }
             }
           }
@@ -2717,13 +2717,15 @@ void FurnaceGUI::drawInsEdit() {
           bool arpMode=ins->std.arpMacro.mode;
 
           const char* dutyLabel="Duty/Noise";
+          int dutyMin=0;
           int dutyMax=3;
           if (ins->type==DIV_INS_C64) {
             dutyLabel="Duty";
             if (ins->c64.dutyIsAbs) {
               dutyMax=4095;
             } else {
-              dutyMax=24;
+              dutyMin=-96;
+              dutyMax=96;
             }
           }
           if (ins->type==DIV_INS_FM) {
@@ -2840,10 +2842,8 @@ void FurnaceGUI::drawInsEdit() {
             if (dutyMax>0) {
               if (ins->type==DIV_INS_MIKEY) {
                 NORMAL_MACRO(ins->std.dutyMacro,0,dutyMax,"duty",dutyLabel,160,ins->std.dutyMacro.open,true,mikeyFeedbackBits,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[2],0,dutyMax,NULL,false);
-              } else if (ins->type==DIV_INS_C64) {
-                NORMAL_MACRO(ins->std.dutyMacro,0,dutyMax,"duty",dutyLabel,160,ins->std.dutyMacro.open,false,NULL,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[2],0,dutyMax,NULL,false);
               } else {
-                NORMAL_MACRO(ins->std.dutyMacro,0,dutyMax,"duty",dutyLabel,160,ins->std.dutyMacro.open,false,NULL,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[2],0,dutyMax,NULL,false);
+                NORMAL_MACRO(ins->std.dutyMacro,dutyMin,dutyMax,"duty",dutyLabel,160,ins->std.dutyMacro.open,false,NULL,false,NULL,0,0,0,0,false,0,macroDummyMode,uiColors[GUI_COLOR_MACRO_OTHER],mmlString[2],dutyMin,dutyMax,NULL,false);
               }
             }
             if (waveMax>0) {

From 3e1c2197ebf1f66f4396e57108f43d4f92a7cdfd Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 18:04:13 -0500
Subject: [PATCH 41/46] OPL: fix #369

---
 src/engine/platform/opl.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/engine/platform/opl.cpp b/src/engine/platform/opl.cpp
index ef9adecf..fac157da 100644
--- a/src/engine/platform/opl.cpp
+++ b/src/engine/platform/opl.cpp
@@ -548,6 +548,9 @@ int DivPlatformOPL::dispatch(DivCommand c) {
       if (chan[c.chan].insChanged) {
         int ops=(slots[3][c.chan]!=255 && chan[c.chan].state.ops==4 && oplType==3)?4:2;
         chan[c.chan].fourOp=(ops==4);
+        if (chan[c.chan].fourOp) {
+          chan[c.chan+1].std.init(NULL);
+        }
         update4OpMask=true;
         for (int i=0; i<ops; i++) {
           unsigned char slot=slots[i][c.chan];

From 2e52a2855ca320b4808eb84fdd7bd918e51a2b76 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 18:07:49 -0500
Subject: [PATCH 42/46] WonderSwan: fix noise phase reset

---
 src/engine/platform/swan.cpp | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/engine/platform/swan.cpp b/src/engine/platform/swan.cpp
index b8f9a40d..86ad9b10 100644
--- a/src/engine/platform/swan.cpp
+++ b/src/engine/platform/swan.cpp
@@ -226,12 +226,14 @@ void DivPlatformSwan::tick(bool sysTick) {
     }
   }
   if (chan[3].std.duty.had) {
-    noise=chan[3].std.duty.val;
-    if (noise>0) {
-      rWrite(0x0e,((noise-1)&0x07)|0x18);
-      sndCtrl|=0x80;
-    } else {
-      sndCtrl&=~0x80;
+    if (noise!=chan[3].std.duty.val) {
+      noise=chan[3].std.duty.val;
+      if (noise>0) {
+        rWrite(0x0e,((noise-1)&0x07)|0x18);
+        sndCtrl|=0x80;
+      } else {
+        sndCtrl&=~0x80;
+      }
     }
   }
   rWrite(0x10,sndCtrl);

From b3f1935f2b3f29f2188a6fa8a8f80a0522b9664d Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 18:23:12 -0500
Subject: [PATCH 43/46] GUI: prepare for more UX improvements

- add "temporary instrument" to DivEngine
- prepare for two things:
  - instrument preview on file picker (at least built-in one)
  - instrument selector for banks (#364)
---
 src/engine/engine.cpp | 10 ++++++++++
 src/engine/engine.h   |  5 +++++
 src/gui/gui.cpp       |  2 +-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index c56eff9c..f77ab635 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -739,6 +739,7 @@ String DivEngine::getWarnings() {
 }
 
 DivInstrument* DivEngine::getIns(int index, DivInstrumentType fallbackType) {
+  if (index==-2 && tempIns!=NULL) return tempIns;
   if (index<0 || index>=song.insLen) {
     switch (fallbackType) {
       case DIV_INS_OPLL:
@@ -1363,6 +1364,15 @@ int DivEngine::addInstrumentPtr(DivInstrument* which) {
   return song.insLen;
 }
 
+void DivEngine::loadTempIns(DivInstrument* which) {
+  BUSY_BEGIN;
+  if (tempIns==NULL) {
+    tempIns=new DivInstrument;
+  }
+  memcpy(tempIns,which,sizeof(DivInstrument));
+  BUSY_END;
+}
+
 void DivEngine::delInstrument(int index) {
   BUSY_BEGIN;
   saveLock.lock();
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 212bf422..5bbb1060 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -302,6 +302,7 @@ class DivEngine {
 
   public:
     DivSong song;
+    DivInstrument* tempIns;
     DivSystem sysOfChan[DIV_MAX_CHANS];
     int dispatchOfChan[DIV_MAX_CHANS];
     int dispatchChanOfChan[DIV_MAX_CHANS];
@@ -525,6 +526,9 @@ class DivEngine {
     // if the returned vector is empty then there was an error.
     std::vector<DivInstrument*> instrumentFromFile(const char* path);
 
+    // load temporary instrument
+    void loadTempIns(DivInstrument* which);
+
     // delete instrument
     void delInstrument(int index);
 
@@ -798,6 +802,7 @@ class DivEngine {
       metroAmp(0.0f),
       metroVol(1.0f),
       totalProcessed(0),
+      tempIns(NULL),
       oscBuf{NULL,NULL},
       oscSize(1),
       oscReadPos(0),
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index a3c41317..26e414e0 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -2419,7 +2419,7 @@ bool FurnaceGUI::loop() {
       }
     }
 
-    wantCaptureKeyboard=ImGui::GetIO().WantCaptureKeyboard;
+    wantCaptureKeyboard=ImGui::GetIO().WantTextInput;
     
     while (true) {
       midiLock.lock();

From 663e724111242d4734d76506091188b2545b4bfc Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 18:41:24 -0500
Subject: [PATCH 44/46] I KNEW IT

---
 src/engine/engine.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index f77ab635..4821df3a 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -1369,7 +1369,7 @@ void DivEngine::loadTempIns(DivInstrument* which) {
   if (tempIns==NULL) {
     tempIns=new DivInstrument;
   }
-  memcpy(tempIns,which,sizeof(DivInstrument));
+  *tempIns=*which;
   BUSY_END;
 }
 

From e8c9b645c53781cfe8863d70e14cb35944cabe48 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 25 Apr 2022 18:58:17 -0500
Subject: [PATCH 45/46] GUI: implement instrument preview in file dialog

SADLY it's just for the built-in file dialog
but i'll think of a solution for the external one
---
 extern/igfd/ImGuiFileDialog.cpp  | 39 ++++++++++++++++++++++----------
 extern/igfd/ImGuiFileDialog.h    | 26 ++++++++++++++-------
 src/engine/engine.cpp            |  6 +++--
 src/engine/platform/amiga.h      |  2 +-
 src/engine/platform/arcade.h     |  2 +-
 src/engine/platform/ay.h         |  3 ++-
 src/engine/platform/ay8930.h     |  3 ++-
 src/engine/platform/bubsyswsg.h  |  3 +--
 src/engine/platform/c64.h        |  4 ++--
 src/engine/platform/fds.h        |  4 ++--
 src/engine/platform/gb.h         |  4 ++--
 src/engine/platform/genesis.h    |  2 +-
 src/engine/platform/genesisext.h |  3 +--
 src/engine/platform/lynx.h       |  4 ++--
 src/engine/platform/mmc5.h       |  4 ++--
 src/engine/platform/nes.h        |  4 ++--
 src/engine/platform/opl.h        |  3 +--
 src/engine/platform/opll.h       |  3 +--
 src/engine/platform/pce.h        |  4 ++--
 src/engine/platform/pcspkr.h     |  4 ++--
 src/engine/platform/pet.h        |  3 +--
 src/engine/platform/qsound.h     |  3 +--
 src/engine/platform/saa.h        |  4 ++--
 src/engine/platform/segapcm.h    |  3 +--
 src/engine/platform/sms.h        |  3 +--
 src/engine/platform/swan.h       |  4 ++--
 src/engine/platform/tia.h        |  4 ++--
 src/engine/platform/tx81z.h      |  3 +--
 src/engine/platform/vera.h       |  4 ++--
 src/engine/platform/vic20.h      |  4 ++--
 src/engine/platform/vrc6.h       |  4 ++--
 src/engine/platform/ym2610.h     |  4 ++--
 src/engine/platform/ym2610b.h    |  4 ++--
 src/engine/platform/ym2610bext.h |  3 +--
 src/engine/platform/ym2610ext.h  |  3 +--
 src/gui/fileDialog.cpp           |  4 ++--
 src/gui/fileDialog.h             |  4 +++-
 src/gui/gui.cpp                  | 10 +++++++-
 38 files changed, 113 insertions(+), 85 deletions(-)

diff --git a/extern/igfd/ImGuiFileDialog.cpp b/extern/igfd/ImGuiFileDialog.cpp
index 3980bcd3..98d6c909 100644
--- a/extern/igfd/ImGuiFileDialog.cpp
+++ b/extern/igfd/ImGuiFileDialog.cpp
@@ -3295,7 +3295,8 @@ namespace IGFD
 		const std::string& vFileName,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3306,6 +3307,7 @@ namespace IGFD
 		prFileDialogInternal.puDLGtitle = vTitle;
 		prFileDialogInternal.puDLGuserDatas = vUserDatas;
 		prFileDialogInternal.puDLGflags = vFlags;
+    prFileDialogInternal.puDLGselFun = vSelectFun;
 		prFileDialogInternal.puDLGoptionsPane = nullptr;
 		prFileDialogInternal.puDLGoptionsPaneWidth = 0.0f;
 		prFileDialogInternal.puDLGmodal = false;
@@ -3335,7 +3337,8 @@ namespace IGFD
 		const std::string& vFilePathName,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3348,6 +3351,7 @@ namespace IGFD
 		prFileDialogInternal.puDLGoptionsPaneWidth = 0.0f;
 		prFileDialogInternal.puDLGuserDatas = vUserDatas;
 		prFileDialogInternal.puDLGflags = vFlags;
+    prFileDialogInternal.puDLGselFun = vSelectFun;
 		prFileDialogInternal.puDLGmodal = false;
 
 		auto ps = IGFD::Utils::ParsePathFileName(vFilePathName);
@@ -3390,7 +3394,8 @@ namespace IGFD
 		const float& vSidePaneWidth,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3401,6 +3406,7 @@ namespace IGFD
 		prFileDialogInternal.puDLGtitle = vTitle;
 		prFileDialogInternal.puDLGuserDatas = vUserDatas;
 		prFileDialogInternal.puDLGflags = vFlags;
+    prFileDialogInternal.puDLGselFun = vSelectFun;
 		prFileDialogInternal.puDLGoptionsPane = vSidePane;
 		prFileDialogInternal.puDLGoptionsPaneWidth = vSidePaneWidth;
 		prFileDialogInternal.puDLGmodal = false;
@@ -3435,7 +3441,8 @@ namespace IGFD
 		const float& vSidePaneWidth,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3448,6 +3455,7 @@ namespace IGFD
 		prFileDialogInternal.puDLGoptionsPaneWidth = vSidePaneWidth;
 		prFileDialogInternal.puDLGuserDatas = vUserDatas;
 		prFileDialogInternal.puDLGflags = vFlags;
+    prFileDialogInternal.puDLGselFun = vSelectFun;
 		prFileDialogInternal.puDLGmodal = false;
 
 		auto ps = IGFD::Utils::ParsePathFileName(vFilePathName);
@@ -3489,7 +3497,8 @@ namespace IGFD
 		const std::string& vFileName,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3497,7 +3506,7 @@ namespace IGFD
 		OpenDialog(
 			vKey, vTitle, vFilters,
 			vPath, vFileName,
-			vCountSelectionMax, vUserDatas, vFlags);
+			vCountSelectionMax, vUserDatas, vFlags, vSelectFun);
 
 		prFileDialogInternal.puDLGmodal = true;
 	}
@@ -3509,7 +3518,8 @@ namespace IGFD
 		const std::string& vFilePathName,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3517,7 +3527,7 @@ namespace IGFD
 		OpenDialog(
 			vKey, vTitle, vFilters,
 			vFilePathName,
-			vCountSelectionMax, vUserDatas, vFlags);
+			vCountSelectionMax, vUserDatas, vFlags, vSelectFun);
 
 		prFileDialogInternal.puDLGmodal = true;
 	}
@@ -3534,7 +3544,8 @@ namespace IGFD
 		const float& vSidePaneWidth,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3543,7 +3554,7 @@ namespace IGFD
 			vKey, vTitle, vFilters,
 			vPath, vFileName,
 			vSidePane, vSidePaneWidth,
-			vCountSelectionMax, vUserDatas, vFlags);
+			vCountSelectionMax, vUserDatas, vFlags, vSelectFun);
 
 		prFileDialogInternal.puDLGmodal = true;
 	}
@@ -3559,7 +3570,8 @@ namespace IGFD
 		const float& vSidePaneWidth,
 		const int& vCountSelectionMax,
 		UserDatas vUserDatas,
-		ImGuiFileDialogFlags vFlags)
+		ImGuiFileDialogFlags vFlags,
+    SelectFun vSelectFun)
 	{
 		if (prFileDialogInternal.puShowDialog) // if already opened, quit
 			return;
@@ -3568,7 +3580,7 @@ namespace IGFD
 			vKey, vTitle, vFilters,
 			vFilePathName,
 			vSidePane, vSidePaneWidth,
-			vCountSelectionMax, vUserDatas, vFlags);
+			vCountSelectionMax, vUserDatas, vFlags, vSelectFun);
 
 		prFileDialogInternal.puDLGmodal = true;
 	}
@@ -3940,6 +3952,9 @@ namespace IGFD
           return 2;
         } else {
 				  fdi.SelectFileName(prFileDialogInternal, vInfos);
+          if (prFileDialogInternal.puDLGselFun!=NULL) {
+            prFileDialogInternal.puDLGselFun(GetFilePathName().c_str());
+          }
         }
 			}
 		}
diff --git a/extern/igfd/ImGuiFileDialog.h b/extern/igfd/ImGuiFileDialog.h
index 2944bfbf..016bd9a1 100644
--- a/extern/igfd/ImGuiFileDialog.h
+++ b/extern/igfd/ImGuiFileDialog.h
@@ -1080,6 +1080,7 @@ namespace IGFD
 
 	typedef void* UserDatas;
 	typedef std::function<void(const char*, UserDatas, bool*)> PaneFun;							// side pane function binding
+  typedef std::function<void(const char*)> SelectFun;                             // click on file function binding
 	class FileDialogInternal
 	{
 	public:
@@ -1103,6 +1104,7 @@ namespace IGFD
 		ImGuiFileDialogFlags puDLGflags = ImGuiFileDialogFlags_None;
 		UserDatas puDLGuserDatas = nullptr;
 		PaneFun puDLGoptionsPane = nullptr;
+    SelectFun puDLGselFun = nullptr;
 		float puDLGoptionsPaneWidth = 0.0f;
 		bool puDLGmodal = false;
 		bool puNeedToExitDialog = false;
@@ -1155,7 +1157,8 @@ namespace IGFD
 			const std::string& vFileName,							// defaut file name
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		void OpenDialog(											// open simple dialog (path and filename are obtained from filePathName)
 			const std::string& vKey,								// key dialog
@@ -1164,7 +1167,8 @@ namespace IGFD
 			const std::string& vFilePathName,						// file path name (will be decompsoed in path and fileName)
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		// with pane
 		void OpenDialog(											// open dialog with custom right pane (path and fileName can be specified)
@@ -1177,7 +1181,8 @@ namespace IGFD
 			const float& vSidePaneWidth = 250.0f,					// side pane width
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		void OpenDialog(											// open dialog with custom right pane (path and filename are obtained from filePathName)
 			const std::string& vKey,								// key dialog
@@ -1188,7 +1193,8 @@ namespace IGFD
 			const float& vSidePaneWidth = 250.0f,					// side pane width
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		// modal dialog
 		void OpenModal(												// open simple modal (path and fileName can be specified)
@@ -1199,7 +1205,8 @@ namespace IGFD
 			const std::string& vFileName,							// defaut file name
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		void OpenModal(												// open simple modal (path and fielname are obtained from filePathName)
 			const std::string& vKey,								// key dialog
@@ -1208,7 +1215,8 @@ namespace IGFD
 			const std::string& vFilePathName,						// file path name (will be decompsoed in path and fileName)
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		// with pane
 		void OpenModal(												// open modal with custom right pane (path and filename are obtained from filePathName)
@@ -1221,7 +1229,8 @@ namespace IGFD
 			const float& vSidePaneWidth = 250.0f,					// side pane width
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		void OpenModal(												// open modal with custom right pane (path and fielname are obtained from filePathName)
 			const std::string& vKey,								// key dialog
@@ -1232,7 +1241,8 @@ namespace IGFD
 			const float& vSidePaneWidth = 250.0f,					// side pane width
 			const int& vCountSelectionMax = 1,						// count selection max
 			UserDatas vUserDatas = nullptr,							// user datas (can be retrieved in pane)
-			ImGuiFileDialogFlags vFlags = 0);						// ImGuiFileDialogFlags 
+			ImGuiFileDialogFlags vFlags = 0,            // ImGuiFileDialogFlags 
+      SelectFun vSelectFun = nullptr);						// function to be called on file click
 
 		// Display / Close dialog form
 		bool Display(												// Display the dialog. return true if a result was obtained (Ok or not)
diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 4821df3a..80fbb5ca 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -739,7 +739,9 @@ String DivEngine::getWarnings() {
 }
 
 DivInstrument* DivEngine::getIns(int index, DivInstrumentType fallbackType) {
-  if (index==-2 && tempIns!=NULL) return tempIns;
+  if (index==-2 && tempIns!=NULL) {
+    return tempIns;
+  }
   if (index<0 || index>=song.insLen) {
     switch (fallbackType) {
       case DIV_INS_OPLL:
@@ -2027,7 +2029,7 @@ void DivEngine::autoNoteOn(int ch, int ins, int note, int vol) {
   }
 
   do {
-    if ((ins<0 || ins>=song.insLen || getChannelType(finalChan)==4 || getPreferInsType(finalChan)==getIns(ins)->type || getIns(ins)->type==DIV_INS_AMIGA) && chan[finalChan].midiNote==-1) {
+    if ((ins==-1 || ins>=song.insLen || getChannelType(finalChan)==4 || getPreferInsType(finalChan)==getIns(ins)->type || getIns(ins)->type==DIV_INS_AMIGA) && chan[finalChan].midiNote==-1) {
       chan[finalChan].midiNote=note;
       pendingNotes.push(DivNoteEvent(finalChan,ins,note,vol,true));
       break;
diff --git a/src/engine/platform/amiga.h b/src/engine/platform/amiga.h
index 07c44ee7..a4c1a7a4 100644
--- a/src/engine/platform/amiga.h
+++ b/src/engine/platform/amiga.h
@@ -34,7 +34,7 @@ class DivPlatformAmiga: public DivDispatch {
     int audSub;
     signed char audDat;
     int sample, wave;
-    unsigned char ins;
+    int ins;
     int busClock;
     int note;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, useWave, setPos, useV, useP;
diff --git a/src/engine/platform/arcade.h b/src/engine/platform/arcade.h
index 41af49e3..e051e8ab 100644
--- a/src/engine/platform/arcade.h
+++ b/src/engine/platform/arcade.h
@@ -37,7 +37,7 @@ class DivPlatformArcade: public DivDispatch {
       DivMacroInt std;
       unsigned char freqH, freqL;
       int freq, baseFreq, pitch, note;
-      unsigned char ins;
+      int ins;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, portaPause, furnacePCM, hardReset;
       int vol, outVol;
diff --git a/src/engine/platform/ay.h b/src/engine/platform/ay.h
index a78f21bc..ce06fc9f 100644
--- a/src/engine/platform/ay.h
+++ b/src/engine/platform/ay.h
@@ -33,7 +33,8 @@ class DivPlatformAY8910: public DivDispatch {
     struct Channel {
       unsigned char freqH, freqL;
       int freq, baseFreq, note, pitch;
-      unsigned char ins, psgMode, autoEnvNum, autoEnvDen;
+      int ins;
+      unsigned char psgMode, autoEnvNum, autoEnvDen;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta;
       int vol, outVol;
diff --git a/src/engine/platform/ay8930.h b/src/engine/platform/ay8930.h
index adbe0be8..61a186f4 100644
--- a/src/engine/platform/ay8930.h
+++ b/src/engine/platform/ay8930.h
@@ -29,7 +29,8 @@ class DivPlatformAY8930: public DivDispatch {
     struct Channel {
       unsigned char freqH, freqL;
       int freq, baseFreq, note, pitch;
-      unsigned char ins, psgMode, autoEnvNum, autoEnvDen, duty;
+      int ins;
+      unsigned char psgMode, autoEnvNum, autoEnvDen, duty;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta;
       int vol, outVol;
diff --git a/src/engine/platform/bubsyswsg.h b/src/engine/platform/bubsyswsg.h
index 2efcc4d9..0fbb2ac5 100644
--- a/src/engine/platform/bubsyswsg.h
+++ b/src/engine/platform/bubsyswsg.h
@@ -28,8 +28,7 @@
 
 class DivPlatformBubSysWSG: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins;
+    int freq, baseFreq, pitch, note, ins;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     signed char vol, outVol, wave;
     signed char waveROM[32] = {0}; // 4 bit PROM per channel on bubble system
diff --git a/src/engine/platform/c64.h b/src/engine/platform/c64.h
index f77e24b9..8df82051 100644
--- a/src/engine/platform/c64.h
+++ b/src/engine/platform/c64.h
@@ -26,8 +26,8 @@
 
 class DivPlatformC64: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, prevFreq, testWhen, note;
-    unsigned char ins, sweep, wave, attack, decay, sustain, release;
+    int freq, baseFreq, pitch, prevFreq, testWhen, note, ins;
+    unsigned char sweep, wave, attack, decay, sustain, release;
     short duty;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta, filter;
     bool resetMask, resetFilter, resetDuty, ring, sync;
diff --git a/src/engine/platform/fds.h b/src/engine/platform/fds.h
index 6d206f3e..bf949272 100644
--- a/src/engine/platform/fds.h
+++ b/src/engine/platform/fds.h
@@ -26,8 +26,8 @@
 
 class DivPlatformFDS: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, prevFreq, note, modFreq;
-    unsigned char ins, duty, sweep, modDepth, modPos;
+    int freq, baseFreq, pitch, prevFreq, note, modFreq, ins;
+    unsigned char duty, sweep, modDepth, modPos;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta, modOn;
     signed char vol, outVol, wave;
     signed char modTable[32];
diff --git a/src/engine/platform/gb.h b/src/engine/platform/gb.h
index df7070ec..c79603ab 100644
--- a/src/engine/platform/gb.h
+++ b/src/engine/platform/gb.h
@@ -27,8 +27,8 @@
 
 class DivPlatformGB: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins, duty, sweep;
+    int freq, baseFreq, pitch, note, ins;
+    unsigned char duty, sweep;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta;
     signed char vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/genesis.h b/src/engine/platform/genesis.h
index aa7659fa..31f11d18 100644
--- a/src/engine/platform/genesis.h
+++ b/src/engine/platform/genesis.h
@@ -37,7 +37,7 @@ class DivPlatformGenesis: public DivDispatch {
       DivMacroInt std;
       unsigned char freqH, freqL;
       int freq, baseFreq, pitch, portaPauseFreq, note;
-      unsigned char ins;
+      int ins;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, furnaceDac, inPorta, hardReset;
       int vol, outVol;
       unsigned char pan;
diff --git a/src/engine/platform/genesisext.h b/src/engine/platform/genesisext.h
index 4cdf9fc6..e3604a34 100644
--- a/src/engine/platform/genesisext.h
+++ b/src/engine/platform/genesisext.h
@@ -25,8 +25,7 @@ class DivPlatformGenesisExt: public DivPlatformGenesis {
   struct OpChannel {
     DivMacroInt std;
     unsigned char freqH, freqL;
-    int freq, baseFreq, pitch, portaPauseFreq;
-    unsigned char ins;
+    int freq, baseFreq, pitch, portaPauseFreq, ins;
     signed char konCycles;
     bool active, insChanged, freqChanged, keyOn, keyOff, portaPause;
     int vol;
diff --git a/src/engine/platform/lynx.h b/src/engine/platform/lynx.h
index 61f6e67d..f1f974ed 100644
--- a/src/engine/platform/lynx.h
+++ b/src/engine/platform/lynx.h
@@ -44,8 +44,8 @@ class DivPlatformLynx: public DivDispatch {
     DivMacroInt std;
     MikeyFreqDiv fd;
     MikeyDuty duty;
-    int baseFreq, pitch, note, actualNote, lfsr;
-    unsigned char ins, pan;
+    int baseFreq, pitch, note, actualNote, lfsr, ins;
+    unsigned char pan;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     signed char vol, outVol;
     Channel():
diff --git a/src/engine/platform/mmc5.h b/src/engine/platform/mmc5.h
index 02ca06e8..879ebee1 100644
--- a/src/engine/platform/mmc5.h
+++ b/src/engine/platform/mmc5.h
@@ -25,8 +25,8 @@
 
 class DivPlatformMMC5: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, prevFreq, note;
-    unsigned char ins, duty, sweep;
+    int freq, baseFreq, pitch, prevFreq, note, ins;
+    unsigned char duty, sweep;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta, furnaceDac;
     signed char vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/nes.h b/src/engine/platform/nes.h
index 2cf2a8a1..7650d39e 100644
--- a/src/engine/platform/nes.h
+++ b/src/engine/platform/nes.h
@@ -25,8 +25,8 @@
 
 class DivPlatformNES: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, prevFreq, note;
-    unsigned char ins, duty, sweep;
+    int freq, baseFreq, pitch, prevFreq, note, ins;
+    unsigned char duty, sweep;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta, furnaceDac;
     signed char vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/opl.h b/src/engine/platform/opl.h
index 76979a54..ee3bcb36 100644
--- a/src/engine/platform/opl.h
+++ b/src/engine/platform/opl.h
@@ -30,8 +30,7 @@ class DivPlatformOPL: public DivDispatch {
       DivInstrumentFM state;
       DivMacroInt std;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins;
+      int freq, baseFreq, pitch, note, ins;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, furnaceDac, inPorta, fourOp;
       int vol, outVol;
       unsigned char pan;
diff --git a/src/engine/platform/opll.h b/src/engine/platform/opll.h
index 04f4f13a..79f905c6 100644
--- a/src/engine/platform/opll.h
+++ b/src/engine/platform/opll.h
@@ -33,8 +33,7 @@ class DivPlatformOPLL: public DivDispatch {
       DivInstrumentFM state;
       DivMacroInt std;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins;
+      int freq, baseFreq, pitch, note, ins;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, furnaceDac, inPorta;
       int vol, outVol;
       unsigned char pan;
diff --git a/src/engine/platform/pce.h b/src/engine/platform/pce.h
index 57a4b033..deb85fbb 100644
--- a/src/engine/platform/pce.h
+++ b/src/engine/platform/pce.h
@@ -31,8 +31,8 @@ class DivPlatformPCE: public DivDispatch {
     int freq, baseFreq, pitch, note;
     int dacPeriod, dacRate;
     unsigned int dacPos;
-    int dacSample;
-    unsigned char ins, pan;
+    int dacSample, ins;
+    unsigned char pan;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, noise, pcm, furnaceDac;
     signed char vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/pcspkr.h b/src/engine/platform/pcspkr.h
index 68e6bf1a..f8813f3f 100644
--- a/src/engine/platform/pcspkr.h
+++ b/src/engine/platform/pcspkr.h
@@ -25,8 +25,8 @@
 
 class DivPlatformPCSpeaker: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins, duty, sweep;
+    int freq, baseFreq, pitch, note, ins;
+    unsigned char duty, sweep;
     bool active, insChanged, freqChanged, sweepChanged, keyOn, keyOff, inPorta, furnaceDac;
     signed char vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/pet.h b/src/engine/platform/pet.h
index 7647a87f..b4b75316 100644
--- a/src/engine/platform/pet.h
+++ b/src/engine/platform/pet.h
@@ -25,8 +25,7 @@
 
 class DivPlatformPET: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins;
+    int freq, baseFreq, pitch, note, ins;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     int vol, outVol, wave;
     unsigned char sreg;
diff --git a/src/engine/platform/qsound.h b/src/engine/platform/qsound.h
index 62b1d647..aa07a3b4 100644
--- a/src/engine/platform/qsound.h
+++ b/src/engine/platform/qsound.h
@@ -30,8 +30,7 @@ class DivPlatformQSound: public DivDispatch {
     int freq, baseFreq, pitch;
     unsigned short audLen;
     unsigned int audPos;
-    int sample, wave;
-    unsigned char ins;
+    int sample, wave, ins;
     int note;
     int panning;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, useWave;
diff --git a/src/engine/platform/saa.h b/src/engine/platform/saa.h
index 0542ff51..30909293 100644
--- a/src/engine/platform/saa.h
+++ b/src/engine/platform/saa.h
@@ -35,8 +35,8 @@ class DivPlatformSAA1099: public DivDispatch {
   protected:
     struct Channel {
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins, psgMode;
+      int freq, baseFreq, pitch, note, ins;
+      unsigned char psgMode;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta;
       int vol, outVol;
diff --git a/src/engine/platform/segapcm.h b/src/engine/platform/segapcm.h
index 4b05c160..3a68a34b 100644
--- a/src/engine/platform/segapcm.h
+++ b/src/engine/platform/segapcm.h
@@ -29,8 +29,7 @@ class DivPlatformSegaPCM: public DivDispatch {
     struct Channel {
       DivMacroInt std;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins;
+      int freq, baseFreq, pitch, note, ins;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, portaPause, furnacePCM;
       int vol, outVol;
diff --git a/src/engine/platform/sms.h b/src/engine/platform/sms.h
index 0aeb9e81..66fdda85 100644
--- a/src/engine/platform/sms.h
+++ b/src/engine/platform/sms.h
@@ -26,8 +26,7 @@
 
 class DivPlatformSMS: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note, actualNote;
-    unsigned char ins;
+    int freq, baseFreq, pitch, note, actualNote, ins;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     signed char vol, outVol;
     DivMacroInt std;
diff --git a/src/engine/platform/swan.h b/src/engine/platform/swan.h
index 0f1643c5..fdad150b 100644
--- a/src/engine/platform/swan.h
+++ b/src/engine/platform/swan.h
@@ -28,8 +28,8 @@
 
 class DivPlatformSwan: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins, pan;
+    int freq, baseFreq, pitch, note, ins;
+    unsigned char pan;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     int vol, outVol, wave;
     DivMacroInt std;
diff --git a/src/engine/platform/tia.h b/src/engine/platform/tia.h
index 3ec3c7f3..602cc6f1 100644
--- a/src/engine/platform/tia.h
+++ b/src/engine/platform/tia.h
@@ -27,8 +27,8 @@
 class DivPlatformTIA: public DivDispatch {
   protected:
     struct Channel {
-      int freq, baseFreq, pitch, note;
-      unsigned char ins, shape;
+      int freq, baseFreq, pitch, note, ins;
+      unsigned char shape;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta;
       int vol, outVol;
diff --git a/src/engine/platform/tx81z.h b/src/engine/platform/tx81z.h
index c61b4bfe..d9261ebd 100644
--- a/src/engine/platform/tx81z.h
+++ b/src/engine/platform/tx81z.h
@@ -35,8 +35,7 @@ class DivPlatformTX81Z: public DivDispatch {
       DivInstrumentFM state;
       DivMacroInt std;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins;
+      int freq, baseFreq, pitch, note, ins;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, portaPause, furnacePCM, hardReset;
       int vol, outVol;
diff --git a/src/engine/platform/vera.h b/src/engine/platform/vera.h
index ec6dcde1..64dee5c7 100644
--- a/src/engine/platform/vera.h
+++ b/src/engine/platform/vera.h
@@ -29,8 +29,8 @@ struct VERA_PCM;
 class DivPlatformVERA: public DivDispatch {
   protected:
     struct Channel {
-      int freq, baseFreq, pitch, note;
-      unsigned char ins, pan;
+      int freq, baseFreq, pitch, note, ins;
+      unsigned char pan;
       bool active, freqChanged, inPorta;
       int vol, outVol;
       unsigned accum;
diff --git a/src/engine/platform/vic20.h b/src/engine/platform/vic20.h
index 7948c5ef..8c15c35d 100644
--- a/src/engine/platform/vic20.h
+++ b/src/engine/platform/vic20.h
@@ -27,8 +27,8 @@
 
 class DivPlatformVIC20: public DivDispatch {
   struct Channel {
-    int freq, baseFreq, pitch, note;
-    unsigned char ins, pan;
+    int freq, baseFreq, pitch, note, ins;
+    unsigned char pan;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta;
     int vol, outVol, wave, waveWriteCycle;
     DivMacroInt std;
diff --git a/src/engine/platform/vrc6.h b/src/engine/platform/vrc6.h
index d28265a4..a44e9d33 100644
--- a/src/engine/platform/vrc6.h
+++ b/src/engine/platform/vrc6.h
@@ -31,8 +31,8 @@ class DivPlatformVRC6: public DivDispatch {
     int freq, baseFreq, pitch, note;
     int dacPeriod, dacRate, dacOut;
     unsigned int dacPos;
-    int dacSample;
-    unsigned char ins, duty;
+    int dacSample, ins;
+    unsigned char duty;
     bool active, insChanged, freqChanged, keyOn, keyOff, inPorta, pcm, furnaceDac;
     signed char vol, outVol;
     DivMacroInt std;
diff --git a/src/engine/platform/ym2610.h b/src/engine/platform/ym2610.h
index e75e24d7..af947199 100644
--- a/src/engine/platform/ym2610.h
+++ b/src/engine/platform/ym2610.h
@@ -43,8 +43,8 @@ class DivPlatformYM2610: public DivDispatch {
     struct Channel {
       DivInstrumentFM state;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins, psgMode, autoEnvNum, autoEnvDen;
+      int freq, baseFreq, pitch, note, ins;
+      unsigned char psgMode, autoEnvNum, autoEnvDen;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta, furnacePCM, hardReset;
       int vol, outVol;
diff --git a/src/engine/platform/ym2610b.h b/src/engine/platform/ym2610b.h
index 6d46ecb2..d2363ed1 100644
--- a/src/engine/platform/ym2610b.h
+++ b/src/engine/platform/ym2610b.h
@@ -35,8 +35,8 @@ class DivPlatformYM2610B: public DivDispatch {
     struct Channel {
       DivInstrumentFM state;
       unsigned char freqH, freqL;
-      int freq, baseFreq, pitch, note;
-      unsigned char ins, psgMode, autoEnvNum, autoEnvDen;
+      int freq, baseFreq, pitch, note, ins;
+      unsigned char psgMode, autoEnvNum, autoEnvDen;
       signed char konCycles;
       bool active, insChanged, freqChanged, keyOn, keyOff, portaPause, inPorta, furnacePCM, hardReset;
       int vol, outVol;
diff --git a/src/engine/platform/ym2610bext.h b/src/engine/platform/ym2610bext.h
index e908916e..c2cd4fb3 100644
--- a/src/engine/platform/ym2610bext.h
+++ b/src/engine/platform/ym2610bext.h
@@ -25,8 +25,7 @@ class DivPlatformYM2610BExt: public DivPlatformYM2610B {
   struct OpChannel {
     DivMacroInt std;
     unsigned char freqH, freqL;
-    int freq, baseFreq, pitch;
-    unsigned char ins;
+    int freq, baseFreq, pitch, ins;
     signed char konCycles;
     bool active, insChanged, freqChanged, keyOn, keyOff, portaPause;
     int vol;
diff --git a/src/engine/platform/ym2610ext.h b/src/engine/platform/ym2610ext.h
index 9fa44d0b..b8922912 100644
--- a/src/engine/platform/ym2610ext.h
+++ b/src/engine/platform/ym2610ext.h
@@ -25,8 +25,7 @@ class DivPlatformYM2610Ext: public DivPlatformYM2610 {
   struct OpChannel {
     DivMacroInt std;
     unsigned char freqH, freqL;
-    int freq, baseFreq, pitch;
-    unsigned char ins;
+    int freq, baseFreq, pitch, ins;
     signed char konCycles;
     bool active, insChanged, freqChanged, keyOn, keyOff, portaPause;
     int vol;
diff --git a/src/gui/fileDialog.cpp b/src/gui/fileDialog.cpp
index 7bfafb4a..3b8fdd46 100644
--- a/src/gui/fileDialog.cpp
+++ b/src/gui/fileDialog.cpp
@@ -4,7 +4,7 @@
 
 #include "../../extern/pfd-fixed/portable-file-dialogs.h"
 
-bool FurnaceGUIFileDialog::openLoad(String header, std::vector<String> filter, const char* noSysFilter, String path, double dpiScale) {
+bool FurnaceGUIFileDialog::openLoad(String header, std::vector<String> filter, const char* noSysFilter, String path, double dpiScale, FileDialogSelectCallback clickCallback) {
   if (opened) return false;
   saving=false;
   curPath=path;
@@ -13,7 +13,7 @@ bool FurnaceGUIFileDialog::openLoad(String header, std::vector<String> filter, c
     dialogO=new pfd::open_file(header,path,filter);
   } else {
     ImGuiFileDialog::Instance()->DpiScale=dpiScale;
-    ImGuiFileDialog::Instance()->OpenModal("FileDialog",header,noSysFilter,path);
+    ImGuiFileDialog::Instance()->OpenModal("FileDialog",header,noSysFilter,path,1,nullptr,0,clickCallback);
   }
   opened=true;
   return true;
diff --git a/src/gui/fileDialog.h b/src/gui/fileDialog.h
index 0dcd82a6..6c5f2faa 100644
--- a/src/gui/fileDialog.h
+++ b/src/gui/fileDialog.h
@@ -7,6 +7,8 @@ namespace pfd {
   class save_file;
 }
 
+typedef std::function<void(const char*)> FileDialogSelectCallback;
+
 class FurnaceGUIFileDialog {
   bool sysDialog;
   bool opened;
@@ -16,7 +18,7 @@ class FurnaceGUIFileDialog {
   pfd::open_file* dialogO;
   pfd::save_file* dialogS;
   public:
-    bool openLoad(String header, std::vector<String> filter, const char* noSysFilter, String path, double dpiScale);
+    bool openLoad(String header, std::vector<String> filter, const char* noSysFilter, String path, double dpiScale, FileDialogSelectCallback clickCallback=NULL);
     bool openSave(String header, std::vector<String> filter, const char* noSysFilter, String path, double dpiScale);
     bool accepted();
     void close();
diff --git a/src/gui/gui.cpp b/src/gui/gui.cpp
index 26e414e0..4aa37b81 100644
--- a/src/gui/gui.cpp
+++ b/src/gui/gui.cpp
@@ -1293,7 +1293,15 @@ void FurnaceGUI::openFileDialog(FurnaceGUIFileDialogs type) {
          "all files", ".*"},
         "compatible files{.fui,.dmp,.tfi,.vgi,.s3i,.sbi,.opli,.opni,.y12,.bnk,.ff,.opm},.*",
         workingDirIns,
-        dpiScale
+        dpiScale,
+        [this](const char* path) {
+          std::vector<DivInstrument*> instruments=e->instrumentFromFile(path);
+          if (!instruments.empty()) {
+            e->loadTempIns(instruments[0]);
+            curIns=-2;
+          }
+          for (DivInstrument* i: instruments) delete i;
+        }
       );
       break;
     case GUI_FILE_INS_SAVE:

From 584e97f313b4337bfc7fc1389d390386aaf72d51 Mon Sep 17 00:00:00 2001
From: cam900 <dbtlrchl@naver.com>
Date: Tue, 26 Apr 2022 09:20:41 +0900
Subject: [PATCH 46/46] Missing header

---
 src/gui/fileDialog.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/gui/fileDialog.h b/src/gui/fileDialog.h
index 6c5f2faa..8d3ff787 100644
--- a/src/gui/fileDialog.h
+++ b/src/gui/fileDialog.h
@@ -1,5 +1,6 @@
 #include "../ta-utils.h"
 #include "imgui.h"
+#include <functional>
 #include <vector>
 
 namespace pfd {