From c78b4b8a3ab9aefcce052219e2ef5a5087505ad8 Mon Sep 17 00:00:00 2001
From: dborth <dborth@ab33defa-829a-11dd-99d6-6900107db72b>
Date: Sat, 11 Oct 2008 06:15:20 +0000
Subject: [PATCH] new frameskip algorithm, update makefiles

---
 Makefile.gc               |  3 ++-
 Makefile.wii              |  3 ++-
 source/ngc/vbasupport.cpp | 39 +++++++++++++++++++++++----------------
 3 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/Makefile.gc b/Makefile.gc
index 0ffb6a7..38352fe 100644
--- a/Makefile.gc
+++ b/Makefile.gc
@@ -26,7 +26,8 @@ INCLUDES 	:=  source/vba source/ngc
 #---------------------------------------------------------------------------------
 
 CFLAGS  = 	-g -O3 -Wall $(MACHDEP) $(INCLUDE) \
-	  		-DNGC -DUSE_VM -DWORDS_BIGENDIAN -DC_CORE -DFINAL_VERSION \
+	  		-DNGC -DUSE_VM -DWORDS_BIGENDIAN \
+	  		-DC_CORE -D__ppc__ -D__POWERPC__ -DFINAL_VERSION \
 	  		-DSDL -DNO_PNG -DHAVE_ZUTIL_H
 CXXFLAGS	= $(CFLAGS)
 LDFLAGS		= -g $(MACHDEP) -Wl,-Map,$(notdir $@).map
diff --git a/Makefile.wii b/Makefile.wii
index c4557d2..90ad224 100644
--- a/Makefile.wii
+++ b/Makefile.wii
@@ -26,7 +26,8 @@ INCLUDES 	:=  source/vba source/ngc
 #---------------------------------------------------------------------------------
 
 CFLAGS  = 	-g -O3 -Wall $(MACHDEP) $(INCLUDE) \
-	  		-DNGC -DWII_DVD -DWORDS_BIGENDIAN -DC_CORE -D__ppc__ -DFINAL_VERSION \
+	  		-DNGC -DWII_DVD -DWORDS_BIGENDIAN -DVIDEO_THREADING \
+	  		-DC_CORE -D__ppc__ -D__POWERPC__ -DFINAL_VERSION \
 	  		-DSDL -DNO_PNG -DHAVE_ZUTIL_H
 CXXFLAGS	= $(CFLAGS)
 LDFLAGS		= -g $(MACHDEP) -Wl,-Map,$(notdir $@).map -Wl,--cref
diff --git a/source/ngc/vbasupport.cpp b/source/ngc/vbasupport.cpp
index 3bc6b4f..2610115 100644
--- a/source/ngc/vbasupport.cpp
+++ b/source/ngc/vbasupport.cpp
@@ -47,9 +47,6 @@ static tb_t start, now;
 
 u32 loadtimeradjust;
 
-static u32 autoFrameSkipLastTime = 0;
-static int frameskipadjust = 0;
-
 int vAspect = 0;
 int hAspect = 0;
 
@@ -132,20 +129,38 @@ void GC_Sleep(u32 dwMiliseconds)
 	}
 }
 */
+
+static u32 autoFrameSkipLastTime = 0;
+
 void system10Frames(int rate)
 {
-	if ( cartridgeType == 1 )
+	if (cartridgeType == 1)
 		return;
 
 	u32 time = systemGetClock();
 	u32 diff = time - autoFrameSkipLastTime;
+
+	// difference should be 1/6 second or (1/6)*1000 ms or 167 ms
+	int timeOff = (167 - diff);
+
+	if(timeOff > 3 && timeOff < 60) // we're running ahead!
+		usleep(timeOff*1000); // let's take a nap
+	else
+		timeOff = 0; // timeoff was not valid
+
+	if(diff > 175 && systemFrameSkip < 9)
+		systemFrameSkip++;
+	else if(diff < 150 && systemFrameSkip > 0)
+		systemFrameSkip--;
+
+	autoFrameSkipLastTime = time + timeOff; // total time = processing time + sleep time
+
+	/*
+	// Original VBA SDL frameskip algorithm
 	int speed = 100;
 
 	if(diff)
 		speed = (1000000/rate)/diff;
-	/*	  char temp[512];
-	sprintf(temp,"Speed: %i",speed);
-	MENU_DrawString( -1, 450,temp , 1 );   */
 
 	if(speed >= 98)
 	{
@@ -174,6 +189,7 @@ void system10Frames(int rate)
 	}
 
 	autoFrameSkipLastTime = time;
+	*/
 }
 
 /****************************************************************************
@@ -518,15 +534,6 @@ void systemDrawScreen()
 {
 	// GB / GBC Have oodles of time - so sync on VSync
 	GX_Render( srcWidth, srcHeight, pix, srcPitch );
-
-	/*#ifdef HW_RVL
-	VIDEO_WaitVSync ();
-	#else
-	if ( cartridgeType == 1 )
-	{
-		VIDEO_WaitVSync();
-	}
-	#endif*/
 }
 
 extern bool gbUpdateSizes();