From 6c2d95f27d6ad59a5117f9115728cc2e5565fb6b Mon Sep 17 00:00:00 2001
From: ramapcsx2 <ramapcsx2@a6443dda-0b58-4228-96e9-037be469359c>
Date: Thu, 16 Oct 2008 13:46:17 +0000
Subject: [PATCH] SPU2Ghz: Part one of a bigger update

git-svn-id: http://pcsx2-playground.googlecode.com/svn/trunk@202 a6443dda-0b58-4228-96e9-037be469359c
---
 plugins/spu2ghz/mixer.cpp  | 26 ++++++++++++++++----------
 plugins/spu2ghz/sndout.cpp | 24 ++++++++++++------------
 2 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/plugins/spu2ghz/mixer.cpp b/plugins/spu2ghz/mixer.cpp
index 3a08222559..d4b5476a08 100644
--- a/plugins/spu2ghz/mixer.cpp
+++ b/plugins/spu2ghz/mixer.cpp
@@ -363,7 +363,8 @@ void GetVoiceValues(s32& Value) {
 	vc.SP+=pitch;
 	while(vc.SP>=4096) 
 	{
-		DT=0;
+		//this isn't needed.  it's garaunteed to be assigned a valid value.
+		//DT=0;
 
 		if(vc.Noise) 
 			GetNoiseValues(DT);
@@ -379,7 +380,6 @@ void GetVoiceValues(s32& Value) {
 	}
 
 	CalculateADSR();
-//	CalculateADSR();
 
 	if(vc.ADSR.Phase==0)
 	{
@@ -388,12 +388,18 @@ void GetVoiceValues(s32& Value) {
 	}
 	else
 	{
-		if(Interpolation==0) {
+		// if SP is zero then we landed perfectly on a sample source, no
+		// interpolation necessary (this is important too, since the
+		// interpolator will pick the wrong sample to mix).
+
+		if(Interpolation==0 || vc.SP == 0) {
 			Data = vc.PV1;
 		} 
 		else if(Interpolation==1) //linear
 		{
-			s64 t0 = vc.PV1 - vc.PV2;
+			// [Air]: Inverted the interpolation delta.  The old way was generating
+			// inverted waveforms.
+			s64 t0 = vc.PV2 - vc.PV1;
 			s64 t1 = vc.PV1;
 			Data = (((t0*vc.SP)>>12) + t1);
 		}
@@ -403,11 +409,11 @@ void GetVoiceValues(s32& Value) {
 			s64 a1 = vc.PV4 - vc.PV3 - a0;
 			s64 a2 = vc.PV1 - vc.PV4;
 			s64 a3 = vc.PV2;
-			s64 mu = vc.SP;
+			s64 mu = 4096-vc.SP;
 
-			s64 t0 = ((a0   )*mu)>>12;
-			s64 t1 = ((t0+a1)*mu)>>12;
-			s64 t2 = ((t1+a2)*mu)>>12;
+			s64 t0 = ((a0   )*mu)>>18; //all 3 were >>12, was causing ugly, loud overflow sound
+			s64 t1 = ((t0+a1)*mu)>>18;
+			s64 t2 = ((t1+a2)*mu)>>18;
 			s64 t3 = ((t2+a3));
 
 			Data = t3;
@@ -417,7 +423,7 @@ void GetVoiceValues(s32& Value) {
 
 		vc.OutX=abs(Value);
 	}
-	if(vc.PeakX<vc.OutX) vc.PeakX=vc.OutX;
+	//if(vc.PeakX<vc.OutX) vc.PeakX=vc.OutX;
 }
 
 /////////////////////////////////////////////////////////////////////////////////////////
@@ -1153,4 +1159,4 @@ buffer[MIX_DEST_B0] = (FB_ALPHA * ACC0) - FB_A0 * (FB_ALPHA^0x8000) - FB_B0 * FB
 buffer[MIX_DEST_B1] = (FB_ALPHA * ACC1) - FB_A1 * (FB_ALPHA^0x8000) - FB_B1 * FB_X;
 
 -----------------------------------------------------------------------------
-*/
\ No newline at end of file
+*/
diff --git a/plugins/spu2ghz/sndout.cpp b/plugins/spu2ghz/sndout.cpp
index 6996e3c1a7..9875dd6619 100644
--- a/plugins/spu2ghz/sndout.cpp
+++ b/plugins/spu2ghz/sndout.cpp
@@ -282,7 +282,7 @@ float valAccum1 = 1.0f;
 float valAccum2 = 1.0f;
 u32   numAccum = 1;
 
-const u32 numUpdates = 112;
+const u32 numUpdates = 96;
 
 float lastTempo=1;
 float cTempo=1;
@@ -312,21 +312,21 @@ void UpdateTempoChange()
 	s32 bufferSize  = sndBuffer->GetBufferSize();
 
 //Emergency stretch to compensate for FPS fluctuations and keep the buffers happy
-	bool a=(bufferUsage < CurBufferSize * 2.5);
-	bool b=(bufferUsage >= (bufferSize - CurBufferSize * 2.5));
+	bool a=(bufferUsage < CurBufferSize * 4);
+	bool b=(bufferUsage >= (bufferSize - CurBufferSize * 4));
 
 	if(a!=b)
 	{
-		if     (bufferUsage < CurBufferSize)	 { cTempo*=0.7f; }
-		else if(bufferUsage < CurBufferSize * 2) { cTempo*=0.90f; }
-		else if(bufferUsage < CurBufferSize * 2.5) { cTempo*=0.95f; }
+		if     (bufferUsage < CurBufferSize * 1.5) { cTempo*=0.70f; }
+		else if(bufferUsage < CurBufferSize * 2)   { cTempo*=0.90f; }
+		else if(bufferUsage < CurBufferSize * 3.9) { cTempo*=0.95f; }
  
-		if     (bufferUsage > (bufferSize - CurBufferSize))     { cTempo*=1.3f; }
-		else if(bufferUsage > (bufferSize - CurBufferSize * 2)) { cTempo*=1.10f; }
-		else if(bufferUsage > (bufferSize - CurBufferSize * 2.5)) { cTempo*=1.05f; }
+		if     (bufferUsage > (bufferSize - CurBufferSize * 1.5)) { cTempo*=1.30f; }
+		else if(bufferUsage > (bufferSize - CurBufferSize * 2))   { cTempo*=1.10f; }
+		else if(bufferUsage > (bufferSize - CurBufferSize * 3.9)) { cTempo*=1.05f; }
 		
 		if (cTempo != lastTempo) {
-			printf("%f %d\n",cTempo,bufferUsage);
+			//printf("%f %d\n",cTempo,bufferUsage);
 			pSoundTouch->setTempo(cTempo);
 		}
 	}
@@ -354,12 +354,12 @@ void UpdateTempoChange()
  
 		if((valAccum < 1.05f) && (valAccum > 0.95f) /*&& (valAccum != 1)*/) 
 		{
-			printf("Timestretch Debug > Playbackpeed: %f (difference disregarded, using 1.0).\n",valAccum);
+			//printf("Timestretch Debug > Playbackpeed: %f (difference disregarded, using 1.0).\n",valAccum);
 			valAccum = 1.0f;
 		}
 		else
 		{
-			printf("Timestretch Debug > Playbackpeed: %f\n",valAccum);
+		//	printf("Timestretch Debug > Playbackpeed: %f\n",valAccum);
 		}
 		
 		if (valAccum != lastTempo) //only update soundtouch object when needed