SMS overscan display

Conflicts:
	BizHawk.Client.EmuHawk/MainForm.Designer.cs

BizHawk.Client.EmuHawk/MainForm.Events.cs

@@ -1625,6 +1625,7 @@ namespace BizHawk.Client.EmuHawk
 			SMSOverclockMenuItem.Checked = ss.AllowOverlock;
 			SMSForceStereoMenuItem.Checked = s.ForceStereoSeparation;
 			SMSSpriteLimitMenuItem.Checked = s.SpriteLimit;
+			SMSDisplayOverscanMenuItem.Checked = s.DisplayOverscan;
 			SMSFix3DGameDisplayToolStripMenuItem.Checked = s.Fix3D;
 			ShowClippedRegionsMenuItem.Checked = s.ShowClippedRegions;
 			HighlightActiveDisplayRegionMenuItem.Checked = s.HighlightActiveDisplayRegion;
@@ -1632,6 +1633,7 @@ namespace BizHawk.Client.EmuHawk
 			SMSEnableFMChipMenuItem.Visible =
 				SMSFix3DGameDisplayToolStripMenuItem.Visible =
 				SMSenableBIOSToolStripMenuItem.Visible =
+				SMSDisplayOverscanMenuItem.Visible =
 				Global.Game.System == "SMS";
 
 			SMSOverclockMenuItem.Visible =
@@ -1727,6 +1729,13 @@ namespace BizHawk.Client.EmuHawk
 			PutCoreSettings(s);
 		}
 
+		private void SMSDisplayOverscanMenuItem_Click(object sender, EventArgs e)
+		{
+			var s = ((SMS)Global.Emulator).GetSettings();
+			s.DisplayOverscan ^= true;
+			PutCoreSettings(s);
+		}
+
 		private void SMSFix3DDisplayMenuItem_Click(object sender, EventArgs e)
 		{
 			var s = ((SMS)Global.Emulator).GetSettings();
@@ -2743,7 +2752,7 @@ namespace BizHawk.Client.EmuHawk
 
 		private void FormDragDrop_internal(object sender, DragEventArgs e)
 		{
-            _FormDragDrop_internal(sender, e);
+			_FormDragDrop_internal(sender, e);
 /*
 			var filePaths = (string[])e.Data.GetData(DataFormats.FileDrop);
 			var isLua = false;

BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.ISettable.cs

@@ -37,6 +37,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 			public bool ForceStereoSeparation = false;
 			public bool SpriteLimit = false;
 			public bool Fix3D = true;
+			public bool DisplayOverscan = false;
 
 			// GG settings
 			public bool ShowClippedRegions = false;

BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs

@@ -191,6 +191,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 			var serviceProvider = ServiceProvider as BasicServiceProvider;
 			serviceProvider.Register<ITraceable>(Tracer);
 			serviceProvider.Register<IDisassemblable>(new Disassembler());
+			Vdp.ProcessOverscan();
 		}
 
 		private ITraceable Tracer { get; set; }

BizHawk.Emulation.Cores/Consoles/Sega/SMS/VDP.Mode4.cs

@@ -271,6 +271,66 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 				FrameBuffer[ofs++] = Palette[BackdropColor];
 		}
 
+		internal int OverscanFrameWidth, OverscanFrameHeight;
+		int overscanTop;
+		int overscanBottom;
+		int overscanLeft;
+		int overscanRight;
+
+		internal void ProcessOverscan()
+		{
+			if (Sms.Settings.DisplayOverscan == false)
+				return;
+
+			if (OverscanFrameBuffer == null)
+			{
+				if (Sms.Region == Common.DisplayType.NTSC)
+				{
+					overscanLeft = 13;
+					overscanRight = 15;
+					overscanTop = 27;
+					overscanBottom = 24;
+				}
+				else // PAL
+				{
+					overscanLeft = 13;
+					overscanRight = 15;
+					overscanTop = 48;
+					overscanBottom = 48;
+				}
+
+				OverscanFrameWidth = overscanLeft + 256 + overscanRight;
+				OverscanFrameHeight = overscanTop + 192 + overscanBottom;
+				OverscanFrameBuffer = new int[OverscanFrameHeight * OverscanFrameWidth];
+			}
+
+			// Top overscan
+			for (int y=0; y<overscanTop; y++)
+				for (int x = 0; x < OverscanFrameWidth; x++)
+					OverscanFrameBuffer[(y * OverscanFrameWidth) + x] = BackgroundColor;
+			
+			// Bottom overscan
+			for (int y = overscanTop + 192; y < OverscanFrameHeight; y++)
+				for (int x = 0; x < OverscanFrameWidth; x++)
+					OverscanFrameBuffer[(y * OverscanFrameWidth) + x] = BackgroundColor;
+
+			// Left overscan
+			for (int y = overscanTop; y < overscanTop + 192; y++)
+				for (int x = 0; x < overscanLeft; x++)
+					OverscanFrameBuffer[(y * OverscanFrameWidth) + x] = BackgroundColor;
+
+			// Right overscan
+			for (int y = overscanTop; y < overscanTop + 192; y++)
+				for (int x = overscanLeft + 256; x < OverscanFrameWidth; x++)
+					OverscanFrameBuffer[(y * OverscanFrameWidth) + x] = BackgroundColor;
+
+			// Active display area
+			for (int y = 0; y < 192; y++)
+				for (int x = 0; x < 256; x++)
+					OverscanFrameBuffer[((y + overscanTop) * OverscanFrameWidth) + overscanLeft + x] = FrameBuffer[y * 256 + x];
+		}
+
+
 		// Handles GG clipping or highlighting
 		internal void ProcessGGScreen()
 		{

BizHawk.Emulation.Cores/Consoles/Sega/SMS/VDP.cs

@@ -49,6 +49,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		public int ScanLine;
 		public int[] FrameBuffer = new int[256 * 192];
 		public int[] GameGearFrameBuffer = new int[160 * 144];
+		public int[] OverscanFrameBuffer = null;
 
 		public bool Mode1Bit { get { return (Registers[1] & 16) > 0; } }
 		public bool Mode2Bit { get { return (Registers[0] & 2) > 0; } }
@@ -369,7 +370,10 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 				Cpu.ExecuteCycles(IPeriod);
 
 				if (ScanLine == scanlinesPerFrame - 1)
+				{
 					ProcessGGScreen();
+					ProcessOverscan();
+				}
 			}
 		}
 
@@ -429,6 +433,12 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 
 		public int[] GetVideoBuffer()
 		{
+			if (mode == VdpMode.SMS && Sms.Settings.DisplayOverscan)
+			{
+				if (OverscanFrameBuffer == null)
+					ProcessOverscan();
+				return OverscanFrameBuffer;
+			}
 			if (mode == VdpMode.SMS || Sms.Settings.ShowClippedRegions)
 				return FrameBuffer;
 			return GameGearFrameBuffer;
@@ -438,6 +448,8 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		{ 
 			get
 			{
+				if (mode == VdpMode.SMS && Sms.Settings.DisplayOverscan)
+					return OverscanFrameWidth;
 				if (mode == MasterSystem.VdpMode.SMS)
 					return 293;
 				else if (Sms.Settings.ShowClippedRegions)
@@ -451,6 +463,8 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		{
 			get
 			{
+				if (mode == VdpMode.SMS && Sms.Settings.DisplayOverscan)
+					return OverscanFrameWidth;
 				if (mode == VdpMode.SMS || Sms.Settings.ShowClippedRegions)
 					return 256;
 				return 160; // GameGear
@@ -461,6 +475,8 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		{
 			get
 			{
+				if (mode == VdpMode.SMS && Sms.Settings.DisplayOverscan)
+					return OverscanFrameHeight;
 				if (mode == VdpMode.SMS || Sms.Settings.ShowClippedRegions)
 					return FrameHeight;
 				return 144; // GameGear