From e2e0afd18a0d8c6ef58239b2dfadb56312700a89 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Sun, 12 Feb 2023 02:11:03 -0500
Subject: [PATCH] ES5506: add a volume scale parameter

---
 src/engine/platform/es5506.cpp | 12 ++++++++++--
 src/engine/platform/es5506.h   |  2 +-
 src/gui/sysConf.cpp            | 10 ++++++++++
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/engine/platform/es5506.cpp b/src/engine/platform/es5506.cpp
index 8e149e1a..2c395db3 100644
--- a/src/engine/platform/es5506.cpp
+++ b/src/engine/platform/es5506.cpp
@@ -385,13 +385,19 @@ void DivPlatformES5506::tick(bool sysTick) {
     if (chan[i].volChanged.changed) {
       // calculate volume (16 bit)
       if (chan[i].volChanged.lVol) {
-        chan[i].resLVol=VOL_SCALE_LOG(chan[i].outVol,chan[i].outLVol,0xfff)<<4;
+        chan[i].resLVol=VOL_SCALE_LOG(chan[i].outVol,chan[i].outLVol,0xfff);
+        chan[i].resLVol-=volScale;
+        if (chan[i].resLVol<0) chan[i].resLVol=0;
+        chan[i].resLVol<<=4;
         if (!chan[i].keyOn && chan[i].active) {
           pageWrite(0x00|i,0x02,chan[i].resLVol);
         }
       }
       if (chan[i].volChanged.rVol) {
-        chan[i].resRVol=VOL_SCALE_LOG(chan[i].outVol,chan[i].outRVol,0xfff)<<4;
+        chan[i].resRVol=VOL_SCALE_LOG(chan[i].outVol,chan[i].outRVol,0xfff);
+        chan[i].resRVol-=volScale;
+        if (chan[i].resRVol<0) chan[i].resRVol=0;
+        chan[i].resRVol<<=4;
         if (!chan[i].keyOn && chan[i].active) {
           pageWrite(0x00|i,0x04,chan[i].resRVol);
         }
@@ -1152,6 +1158,7 @@ void DivPlatformES5506::setFlags(const DivConfig& flags) {
   CHECK_CUSTOM_CLOCK;
 
   initChanMax=MAX(4,flags.getInt("channels",0x1f)&0x1f);
+  volScale=4095-flags.getInt("volScale",4095);
   chanMax=initChanMax;
   pageWriteMask(0x00,0x60,0x0b,chanMax);
 
@@ -1251,6 +1258,7 @@ int DivPlatformES5506::init(DivEngine* p, int channels, int sugRate, const DivCo
   parent=p;
   dumpWrites=false;
   skipRegisterWrites=false;
+  volScale=0;
 
   for (int i=0; i<32; i++) {
     isMuted[i]=false;
diff --git a/src/engine/platform/es5506.h b/src/engine/platform/es5506.h
index 2df07b77..56a1f629 100644
--- a/src/engine/platform/es5506.h
+++ b/src/engine/platform/es5506.h
@@ -266,7 +266,7 @@ class DivPlatformES5506: public DivDispatch, public es550x_intf {
   std::queue<QueuedHostIntf> hostIntf8;
   std::queue<unsigned char> queuedRead;
   std::queue<QueuedReadState> queuedReadState;
-  int cycle, curPage;
+  int cycle, curPage, volScale;
   unsigned char maskedVal;
   unsigned int irqv;
   bool isMasked, isReaded;
diff --git a/src/gui/sysConf.cpp b/src/gui/sysConf.cpp
index b3783ddf..f19e9481 100644
--- a/src/gui/sysConf.cpp
+++ b/src/gui/sysConf.cpp
@@ -883,6 +883,7 @@ bool FurnaceGUI::drawSysConf(int chan, DivSystem type, DivConfig& flags, bool mo
     }
     case DIV_SYSTEM_ES5506: {
       int channels=flags.getInt("channels",0x1f)+1;
+      int volScale=flags.getInt("volScale",4095);
       ImGui::Text("Initial channel limit:");
       if (CWSliderInt("##OTTO_InitialChannelLimit",&channels,5,32)) {
         if (channels<5) channels=5;
@@ -890,9 +891,18 @@ bool FurnaceGUI::drawSysConf(int chan, DivSystem type, DivConfig& flags, bool mo
         altered=true;
       } rightClickable
 
+      ImGui::Text("Volume scale:");
+
+      if (CWSliderInt("##VolScaleO",&volScale,0,4095)) {
+        if (volScale<0) volScale=0;
+        if (volScale>4095) volScale=4095;
+        altered=true;
+      } rightClickable
+
       if (altered) {
         e->lockSave([&]() {
           flags.set("channels",channels-1);
+          flags.set("volScale",volScale);
         });
       }
       break;