From 11478fbdfe503717a997fd1e507927a37fd3cb68 Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 27 Dec 2021 15:22:57 -0500
Subject: [PATCH] prevent clipping in ADPCM samples

---
 src/engine/engine.cpp | 6 ++++++
 src/engine/engine.h   | 2 +-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/engine/engine.cpp b/src/engine/engine.cpp
index 678a5bd05..28ff1373d 100644
--- a/src/engine/engine.cpp
+++ b/src/engine/engine.cpp
@@ -1367,6 +1367,8 @@ void DivEngine::renderSamples() {
       step=adSteps[index];
 
       short sample=(j<s->rendLength)?((s->depth==16)?(s->rendData[j]>>4):(s->rendData[j]<<4)):0;
+      if (sample>0x7d0) sample=0x7d0;
+      if (sample<-0x7d0) sample=-0x7d0;
       diff=sample-predsample;
       if (diff>=0) {
         encoded=0;
@@ -1389,6 +1391,9 @@ void DivEngine::renderSamples() {
       if (diff>=tempstep) encoded|=1;
 
       acc+=jediTable[decstep+encoded];
+      if (acc>0x7ff || acc<-0x800) {
+        logW("clipping! %d\n",acc);
+      }
       acc&=0xfff;
       if (acc&0x800) acc|=~0xfff;
       decstep+=adStepSeek[encoded&7]*16;
@@ -1552,6 +1557,7 @@ void DivEngine::reset() {
   extValuePresent=0;
   speed1=song.speed1;
   speed2=song.speed2;
+  globalPitch=0;
   dispatch->reset();
 }
 
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 1d252a968..a4eae07fc 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -80,7 +80,7 @@ class DivEngine {
   bool extValuePresent;
   bool repeatPattern;
   int ticks, cycles, curRow, curOrder, remainingLoops, nextSpeed, clockDrift;
-  int changeOrd, changePos, totalTicks, totalCmds, lastCmds, cmdsPerSecond;
+  int changeOrd, changePos, totalTicks, totalCmds, lastCmds, cmdsPerSecond, globalPitch;
   unsigned char extValue;
   unsigned char speed1, speed2;
   DivStatusView view;