dev110 - add cut/delay effect policy compat flag

INCOMPLETE!!!

src/engine/engine.h

@@ -46,8 +46,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev109"
-#define DIV_ENGINE_VERSION 109
+#define DIV_VERSION "dev110"
+#define DIV_ENGINE_VERSION 110
 
 // for imports
 #define DIV_VERSION_MOD 0xff01

src/engine/fileOps.cpp

@@ -176,6 +176,7 @@ bool DivEngine::loadDMF(unsigned char* file, size_t len) {
     ds.e1e2StopOnSameNote=true;
     ds.brokenPortaArp=false;
     ds.snNoLowPeriods=true;
+    ds.delayBehavior=0;
 
     // 1.1 compat flags
     if (ds.version>24) {
@@ -1067,6 +1068,9 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
     if (ds.version<108) {
       ds.snNoLowPeriods=true;
     }
+    if (ds.version<110) {
+      ds.delayBehavior=1;
+    }
     ds.isDMF=false;
 
     reader.readS(); // reserved
@@ -1484,7 +1488,12 @@ bool DivEngine::loadFur(unsigned char* file, size_t len) {
       } else {
         reader.readC();
       }
-      for (int i=0; i<6; i++) {
+      if (ds.version>=110) {
+        ds.delayBehavior=reader.readC();
+      } else {
+        reader.readC();
+      }
+      for (int i=0; i<5; i++) {
         reader.readC();
       }
     }
@@ -1917,6 +1926,7 @@ bool DivEngine::loadMod(unsigned char* file, size_t len) {
     ds.noSlidesOnFirstTick=true;
     ds.rowResetsArpPos=true;
     ds.ignoreJumpAtEnd=false;
+    ds.delayBehavior=0;
 
     int insCount=31;
     bool bypassLimits=false;
@@ -3729,7 +3739,8 @@ SafeWriter* DivEngine::saveFur(bool notPrimary) {
   w->writeC(song.e1e2StopOnSameNote);
   w->writeC(song.brokenPortaArp);
   w->writeC(song.snNoLowPeriods);
-  for (int i=0; i<6; i++) {
+  w->writeC(song.delayBehavior);
+  for (int i=0; i<5; i++) {
     w->writeC(0);
   }
 

src/engine/playback.cpp

@@ -361,7 +361,9 @@ void DivEngine::processRow(int i, bool afterDelay) {
           break;
         case 0xed: // delay
           if (effectVal!=0) {
-            if (effectVal<=nextSpeed) {
+            bool comparison=(song.delayBehavior==1)?(effectVal<=nextSpeed):(effectVal<nextSpeed);
+            if (song.delayBehavior==2) comparison=true;
+            if (comparison) {
               chan[i].rowDelay=effectVal+1;
               chan[i].delayOrder=whatOrder;
               chan[i].delayRow=whatRow;
@@ -372,6 +374,7 @@ void DivEngine::processRow(int i, bool afterDelay) {
               }
               returnAfterPre=true;
             } else {
+              logV("higher than nextSpeed! %d>%d",effectVal,nextSpeed);
               chan[i].delayLocked=false;
             }
           }

src/engine/song.h

@@ -463,6 +463,11 @@ struct DivSong {
   // 1: fake reset on loop
   // 2: don't do anything on loop
   unsigned char loopModality;
+  // cut/delay effect behavior
+  // 0: strict (don't allow value higher than or equal to speed)
+  // 1: broken (don't allow value higher than speed)
+  // 2: lax (allow value higher than speed)
+  unsigned char delayBehavior;
   bool properNoiseLayout;
   bool waveDutyIsVol;
   bool resetMacroOnPorta;
@@ -565,6 +570,7 @@ struct DivSong {
     linearPitch(2),
     pitchSlideSpeed(4),
     loopModality(0),
+    delayBehavior(2),
     properNoiseLayout(true),
     waveDutyIsVol(false),
     resetMacroOnPorta(false),

src/gui/compatFlags.cpp

@@ -193,6 +193,26 @@ void FurnaceGUI::drawCompatFlags() {
       ImGui::SetTooltip("select to not reset channels on loop.");
     }
 
+    ImGui::Text("Cut/delay effect policy:");
+    if (ImGui::RadioButton("Strict",e->song.delayBehavior==0)) {
+      e->song.delayBehavior=0;
+    }
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("only when time is less than speed (like DefleMask/ProTracker)");
+    }
+    if (ImGui::RadioButton("Strict (old)",e->song.delayBehavior==1)) {
+      e->song.delayBehavior=1;
+    }
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("only when time is less than or equal to speed (original buggy behavior)");
+    }
+    if (ImGui::RadioButton("Lax",e->song.delayBehavior==2)) {
+      e->song.delayBehavior=2;
+    }
+    if (ImGui::IsItemHovered()) {
+      ImGui::SetTooltip("no checks (like FamiTracker)");
+    }
+
     ImGui::Separator();
 
     ImGui::TextWrapped("the following flags are for compatibility with older Furnace versions.");