Adding Stella as A2600 emulation core (#3911)

* Adding initial version of the core

* Adding base files

* Trying to load waterbox now

* Adding stella

* Adding bk class

* Compiling bk interface to stella core

* Now compiling against Stella + SDL2-based BK backend

* Progress

* More progress

* Frame advancing (no render)

* Calling video update but crashing on zero div

* Now rendering to screen with correct palette

* Now rendering appropriately and with correct palette based on region

* Now reading controls

* Trying to capture audio

* Now adding audio

* Now polling inputs

* Now polling inputs

* Now reporting memory regions

* Added memory regions

* Removing debug prints

* Fixing indent

* Adding stella core

* Updating readme and make all cores

* Recovering ending comma

* Using heap alloc for sound buffer

* Removing unnecessary files

* Update src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IMemoryDomains.cs

Co-authored-by: James Groom <OSSYoshiRulz+GitHub@gmail.com>

* Update src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IMemoryDomains.cs

Co-authored-by: James Groom <OSSYoshiRulz+GitHub@gmail.com>

* Fix

* Restoring vscode

* Removing warning

* Update waterbox readme

* Fix Stella's `[Core]` attr

* Increased sound buffer size to 1Mb, as some games need more than 4K

---------

Co-authored-by: James Groom <OSSYoshiRulz+GitHub@gmail.com>
Co-authored-by: Morilli <35152647+Morilli@users.noreply.github.com>
Co-authored-by: YoshiRulz <OSSYoshiRulz+git@gmail.com>

.github/workflows/make.yml

@@ -60,6 +60,7 @@ jobs:
            git submodule update --init gpgx/Genesis-Plus-GX;
            git submodule update --init ../submodules/sameboy/libsameboy;
            git submodule update --init uae/libretro-uae;
+           git submodule update --init stella/core;
     - name: Download compiled waterbox
       uses: actions/download-artifact@v4
       with:
@@ -100,6 +101,7 @@ jobs:
           Assets/dll/turbo.wbx.zst
           Assets/dll/uzem.wbx.zst
           Assets/dll/vb.wbx.zst
+          Assets/dll/stella.wbx.zst
           Assets/dll/virtualjaguar.wbx.zst
 
   build-mame:

.gitmodules

@@ -74,6 +74,10 @@
 	path = waterbox/gpgx/Genesis-Plus-GX
 	url = https://github.com/TASEmulators/Genesis-Plus-GX.git
 	branch = tasvideos-2.2
+[submodule "waterbox/stella/core"]
+	path = waterbox/stella/core
+	url = https://github.com/TASEmulators/stella.git
+	branch = tasvideos-1
 [submodule "waterbox/uae/libretro-uae"]
 	path = waterbox/uae/libretro-uae
 	url = https://github.com/TASEmulators/libretro-uae.git

src/BizHawk.Client.Common/config/Config.cs

@@ -25,6 +25,8 @@ namespace BizHawk.Client.Common
 		/// </remarks>
 		public static readonly IReadOnlyList<(string[] AppliesTo, string[] CoreNames)> CorePickerUIData = new List<(string[], string[])>
 		{
+			([ VSystemID.Raw.A26 ],
+				[ CoreNames.Stella, CoreNames.Atari2600Hawk ]),
 			([ VSystemID.Raw.Satellaview ],
 				[ CoreNames.Bsnes115, CoreNames.SubBsnes115 ]),
 			([ VSystemID.Raw.GB, VSystemID.Raw.GBC ],
@@ -49,6 +51,7 @@ namespace BizHawk.Client.Common
 				[ CoreNames.Snes9X, CoreNames.Bsnes115, CoreNames.SubBsnes115, CoreNames.Faust, CoreNames.Bsnes ]),
 			([ VSystemID.Raw.TI83 ],
 				[ CoreNames.Emu83, CoreNames.TI83Hawk ]),
+
 		};
 
 		public static Dictionary<string, string> GenDefaultCorePreferences()

src/BizHawk.Emulation.Common/Enums.cs

@@ -7,7 +7,8 @@
 	{
 		NTSC,
 		PAL,
-		Dendy
+		Dendy,
+		SECAM
 	}
 
 	/// <summary>

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/LibStella.cs

@@ -0,0 +1,80 @@
+using System.Runtime.InteropServices;
+
+using BizHawk.BizInvoke;
+
+namespace BizHawk.Emulation.Cores.Consoles.Atari.Stella
+{
+	public abstract class CInterface
+	{
+
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		public delegate int load_archive_cb(string filename, IntPtr buffer, int maxsize);
+
+		[StructLayout(LayoutKind.Sequential)]
+		public class InitSettings
+		{
+			public uint dummy;
+		}
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_get_audio(ref int n, ref IntPtr buffer);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract int stella_get_region();
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract bool stella_init(
+			string fileName,
+			load_archive_cb feload_archive_cb,
+			[In]InitSettings settings);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_frame_advance(int port1, int port2, bool reset, bool power, bool leftDiffToggled, bool rightDiffToggled);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_get_video(out int w, out int h, out int pitch, ref IntPtr buffer);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_get_frame_rate(out int fps);
+
+		[UnmanagedFunctionPointer(CallingConvention.Cdecl)]
+		public delegate void input_cb();
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_set_input_callback(input_cb cb);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract byte stella_peek_tia(uint addr);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_poke_tia(uint addr, byte value);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract byte stella_peek_m6532(uint addr);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_poke_m6532(uint addr, byte value);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract byte stella_peek_systembus(uint addr);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_poke_systembus(uint addr, byte value);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract uint stella_get_cartram_size();
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract byte stella_peek_cartram(uint addr);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_poke_cartram(uint addr, byte value);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract void stella_get_mainram_ptr(ref IntPtr addr);
+
+		[BizImport(CallingConvention.Cdecl)]
+		public abstract IntPtr stella_get_cart_type();
+
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.Core.cs

@@ -0,0 +1,99 @@
+using BizHawk.Emulation.Cores.Components.M6502;
+using System.Runtime.CompilerServices;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella
+	{
+		internal struct CpuLink : IMOS6502XLink
+		{
+			public byte DummyReadMemory(ushort address) { return 0; }
+
+			public void OnExecFetch(ushort address) { }
+
+			public byte PeekMemory(ushort address) { return 0; }
+
+			public byte ReadMemory(ushort address) { return 0; }
+
+			public void WriteMemory(ushort address, byte value) { }
+		}
+
+		internal byte BaseReadMemory(ushort addr)
+		{
+			return 0;
+		}
+
+		internal byte BasePeekMemory(ushort addr)
+		{
+
+			return 0;
+		}
+
+		internal void BaseWriteMemory(ushort addr, byte value)
+		{
+		}
+
+		internal void BasePokeMemory(ushort addr, byte value)
+		{
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private byte ReadMemory(ushort addr)
+		{
+			return 0;
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private void WriteMemory(ushort addr, byte value)
+		{
+		}
+
+		internal void PokeMemory(ushort addr, byte value)
+		{
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private void ExecFetch(ushort addr)
+		{
+		}
+
+		private void RebootCore()
+		{
+		}
+
+		private void HardReset()
+		{
+		}
+
+		private void Cycle()
+		{
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		internal byte ReadControls1(bool peek)
+		{
+			return 0;
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		internal byte ReadControls2(bool peek)
+		{
+			return 0;
+		}
+
+		internal int ReadPot1(int pot)
+		{
+			return 0;
+		}
+
+		internal int ReadPot2(int pot)
+		{
+			return 0;
+		}
+
+		internal byte ReadConsoleSwitches(bool peek)
+		{
+			return 0;
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IEmulator.cs

@@ -0,0 +1,65 @@
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : IEmulator
+	{
+		public IEmulatorServiceProvider ServiceProvider { get; }
+
+		public ControllerDefinition ControllerDefinition => _controllerDeck.Definition;
+
+        private bool _leftDifficultyToggled = false;
+		private bool _rightDifficultyToggled = false;
+
+		public bool FrameAdvance(IController controller, bool render, bool renderSound)
+		{
+			
+			int port1 = _controllerDeck.ReadPort1(controller);
+			int port2 = _controllerDeck.ReadPort2(controller);
+            
+			// Handle all the console controls here
+			bool powerPressed = false;
+			bool resetPressed = false;
+			if (controller.IsPressed("Power")) powerPressed = true;
+			if (controller.IsPressed("Reset")) resetPressed = true;
+			if (controller.IsPressed("Toggle Left Difficulty"))	_leftDifficultyToggled = !_leftDifficultyToggled;
+			if (controller.IsPressed("Toggle Right Difficulty")) _rightDifficultyToggled = !_rightDifficultyToggled;
+
+			IsLagFrame = true;
+
+			Core.stella_frame_advance(port1, port2, resetPressed, powerPressed, _leftDifficultyToggled, _rightDifficultyToggled);
+
+			if (IsLagFrame)
+				LagCount++;
+
+			if (render)
+				UpdateVideo();
+
+			if (renderSound)
+				update_audio();
+
+			_frame++;
+
+			return true;
+		}
+
+		public int _frame;
+
+		public int Frame => _frame;
+
+		public string SystemId => VSystemID.Raw.A26;
+
+		public bool DeterministicEmulation => true;
+
+		public void ResetCounters()
+		{
+			_frame = 0;
+			LagCount = 0;
+			IsLagFrame = false;
+		}
+
+		public void Dispose()
+		{
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IInputPollable.cs

@@ -0,0 +1,24 @@
+using BizHawk.Emulation.Common;
+using BizHawk.Emulation.Cores.Consoles.Atari.Stella;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : IInputPollable
+	{
+		public int LagCount { get; set; }
+
+		public bool IsLagFrame { get; set; }
+
+		public IInputCallbackSystem InputCallbacks => _inputCallbacks;
+
+		private readonly CInterface.input_cb _inputCallback;
+
+		private readonly InputCallbackSystem _inputCallbacks = new InputCallbackSystem();
+
+		private void input_callback()
+		{
+			InputCallbacks.Call();
+			IsLagFrame = false;
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IMemoryDomains.cs

@@ -0,0 +1,64 @@
+using System.Collections.Generic;
+
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella
+	{
+		internal IMemoryDomains MemoryDomains;
+		private uint _cartMemSize;
+
+		private void SetupMemoryDomains()
+		{
+			_cartMemSize = Core.stella_get_cartram_size();
+			var mainRamAddress = IntPtr.Zero;
+			var cartDPCRamAddress = IntPtr.Zero;
+			Core.stella_get_mainram_ptr(ref mainRamAddress);
+
+			var domains = new List<MemoryDomain>
+			{
+				new MemoryDomainDelegate(
+					"TIA",
+					16,
+					MemoryDomain.Endian.Little,
+					addr => Core.stella_peek_tia((uint)addr),
+					(addr, value) => Core.stella_poke_tia((uint)addr, value),
+					1),
+
+				new MemoryDomainDelegate(
+					"PIA",
+					1024,
+					MemoryDomain.Endian.Little,
+					addr => Core.stella_peek_m6532((uint)addr),
+					(addr, value) => Core.stella_poke_m6532((uint)addr, value),
+					1),
+
+				new MemoryDomainDelegate(
+					"System Bus",
+					65536,
+					MemoryDomain.Endian.Little,
+					addr => Core.stella_peek_systembus((uint) addr),
+					(addr, value) => Core.stella_poke_systembus((uint) addr, value),
+					1)
+			};
+
+			if (_cartMemSize > 0)
+			{
+				domains.Add(new MemoryDomainDelegate(
+					"Cart Ram",
+					_cartMemSize,
+					MemoryDomain.Endian.Little,
+					addr => Core.stella_peek_cartram((uint)addr),
+					(addr, value) => Core.stella_poke_cartram((uint)addr, value),
+					1));
+			}
+
+			MemoryDomainIntPtrMonitor mainRAM = new("Main RAM", MemoryDomain.Endian.Little, mainRamAddress, 128, true, 1, _elf);
+			domains.Add(mainRAM);
+			
+			MemoryDomains = new MemoryDomainList(domains) { MainMemory = mainRAM };
+			((BasicServiceProvider)ServiceProvider).Register(MemoryDomains);
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.ISettable.cs

@@ -0,0 +1,206 @@
+using System.ComponentModel;
+using System.Drawing;
+
+using Newtonsoft.Json;
+
+using BizHawk.Emulation.Common;
+using BizHawk.Common;
+using BizHawk.Emulation.Cores.Consoles.Atari.Stella;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : ISettable<Stella.A2600Settings, Stella.A2600SyncSettings>
+	{
+		public A2600Settings GetSettings()
+		{
+			return Settings.Clone();
+		}
+
+		public A2600SyncSettings GetSyncSettings()
+		{
+			return SyncSettings.Clone();
+		}
+
+		public PutSettingsDirtyBits PutSettings(A2600Settings o)
+		{
+			Settings = o;
+			return PutSettingsDirtyBits.None;
+		}
+
+		public PutSettingsDirtyBits PutSyncSettings(A2600SyncSettings o)
+		{
+			bool ret = A2600SyncSettings.NeedsReboot(SyncSettings, o);
+			SyncSettings = o;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
+		}
+
+		internal A2600Settings Settings { get; private set; }
+		internal A2600SyncSettings SyncSettings { get; private set; }
+
+		[CoreSettings]
+		public class A2600Settings
+		{
+			[JsonIgnore]
+			private int _ntscTopLine;
+
+			[JsonIgnore]
+			private int _ntscBottomLine;
+
+			[JsonIgnore]
+			private int _palTopLine;
+
+			[JsonIgnore]
+			private int _palBottomLine;
+
+			[DisplayName("Show Background")]
+			[Description("Sets whether or not the Background layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowBG { get; set; }
+
+			[DisplayName("Show Player 1")]
+			[Description("Sets whether or not the Player 1 layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowPlayer1 { get; set; }
+
+			[DisplayName("Show Player 2")]
+			[Description("Sets whether or not the Player 2 layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowPlayer2 { get; set; }
+
+			[DisplayName("Show Missle 1")]
+			[Description("Sets whether or not the Missle 1 layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowMissle1 { get; set; }
+
+			[DisplayName("Show Missle 2")]
+			[Description("Sets whether or not the Missle 2 layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowMissle2 { get; set; }
+
+			[DisplayName("Show Ball")]
+			[Description("Sets whether or not the Ball layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowBall { get; set; }
+
+			[DisplayName("Show Playfield")]
+			[Description("Sets whether or not the Playfield layer will be displayed")]
+			[DefaultValue(true)]
+			public bool ShowPlayfield { get; set; }
+
+			[DisplayName("SECAM Colors")]
+			[Description("If true, PAL mode will show with SECAM (French) colors.")]
+			[DefaultValue(false)]
+			public bool SECAMColors { get; set; }
+
+			[DisplayName("NTSC Top Line")]
+			[Description("First line of the video image to display in NTSC mode.")]
+			[DefaultValue(24)]
+			public int NTSCTopLine
+			{
+				get => _ntscTopLine;
+				set => _ntscTopLine = Math.Min(64, Math.Max(value, 0));
+			}
+
+			[DisplayName("NTSC Bottom Line")]
+			[Description("Last line of the video image to display in NTSC mode.")]
+			[DefaultValue(248)]
+			public int NTSCBottomLine
+			{
+				get => _ntscBottomLine;
+				set => _ntscBottomLine = Math.Min(260, Math.Max(value, 192));
+			}
+
+			[DisplayName("PAL Top Line")]
+			[Description("First line of the video image to display in PAL mode.")]
+			[DefaultValue(24)]
+			public int PALTopLine
+			{
+				get => _palTopLine;
+				set => _palTopLine = Math.Min(64, Math.Max(value, 0));
+			}
+
+			[DisplayName("PAL Bottom Line")]
+			[Description("Last line of the video image to display in PAL mode.")]
+			[DefaultValue(296)]
+			public int PALBottomLine
+			{
+				get => _palBottomLine;
+				set => _palBottomLine = Math.Min(310, Math.Max(value, 192));
+			}
+
+			[DisplayName("Background Color")]
+			[DefaultValue(typeof(Color), "Black")]
+			public Color BackgroundColor { get; set; }
+
+			public A2600Settings Clone()
+			{
+				return (A2600Settings)MemberwiseClone();
+			}
+
+			public A2600Settings()
+			{
+				SettingsUtil.SetDefaultValues(this);
+			}
+		}
+
+		[CoreSettings]
+		public class A2600SyncSettings
+		{
+			[DefaultValue(Atari2600ControllerTypes.Joystick)]
+			[DisplayName("Port 1 Device")]
+			[Description("The type of controller plugged into the first controller port")]
+			[TypeConverter(typeof(DescribableEnumConverter))]
+			public Atari2600ControllerTypes Port1 { get; set; } = Atari2600ControllerTypes.Joystick;
+
+			[DefaultValue(Atari2600ControllerTypes.Joystick)]
+			[DisplayName("Port 2 Device")]
+			[Description("The type of controller plugged into the second controller port")]
+			[TypeConverter(typeof(DescribableEnumConverter))]
+			public Atari2600ControllerTypes Port2 { get; set; } = Atari2600ControllerTypes.Joystick;
+
+			[DisplayName("Black and White Mode")]
+			[Description("Set the TV Type switch on the console to B&W or Color.  This only affects the displayed image if the game supports it.")]
+			[DefaultValue(false)]
+			public bool BW { get; set; }
+
+			[DisplayName("Left Difficulty")]
+			[Description("Set the Left Difficulty switch on the console")]
+			[DefaultValue(true)]
+			public bool LeftDifficulty { get; set; }
+
+			[DisplayName("Right Difficulty")]
+			[Description("Set the Right Difficulty switch on the console")]
+			[DefaultValue(true)]
+			public bool RightDifficulty { get; set; }
+
+			[DisplayName("Super Charger BIOS Skip")]
+			[Description("On Super Charger carts, this will skip the BIOS intro")]
+			[DefaultValue(false)]
+			public bool FastScBios { get; set; }
+
+
+			public CInterface.InitSettings GetNativeSettings(GameInfo game)
+			{
+				return new CInterface.InitSettings
+				{
+					dummy = 1
+				};
+			}
+
+			public A2600SyncSettings Clone()
+			{
+				return (A2600SyncSettings)MemberwiseClone();
+			}
+
+			public A2600SyncSettings()
+			{
+				SettingsUtil.SetDefaultValues(this);
+			}
+
+			public static bool NeedsReboot(A2600SyncSettings x, A2600SyncSettings y)
+			{
+				return !DeepEquality.DeepEquals(x, y);
+			}
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.ISoundProvider.cs

@@ -0,0 +1,53 @@
+using BizHawk.Emulation.Common;
+using System.Runtime.InteropServices;
+using BizHawk.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : ISoundProvider
+	{
+		private readonly short[] _samples = new short[4096];
+		private int _nsamp;
+
+		public bool CanProvideAsync => false;
+
+		public void GetSamplesSync(out short[] samples, out int nsamp)
+		{
+			nsamp = _nsamp;
+			samples = _samples;
+			_nsamp = 0;
+		}
+
+		public void DiscardSamples()
+		{
+			_nsamp = 0;
+		}
+
+		public void SetSyncMode(SyncSoundMode mode)
+		{
+			if (mode == SyncSoundMode.Async)
+			{
+				throw new NotSupportedException("Async mode is not supported.");
+			}
+
+		}
+		public SyncSoundMode SyncMode => SyncSoundMode.Sync;
+
+		public void GetSamplesAsync(short[] samples)
+		{
+			throw new InvalidOperationException("Async mode is not supported.");
+		}
+
+		private void update_audio()
+		{
+			IntPtr src = IntPtr.Zero;
+			Core.stella_get_audio(ref _nsamp, ref src);
+
+			if (src != IntPtr.Zero)
+			{
+				using (_elf.EnterExit())
+					Marshal.Copy(src, _samples, 0, _nsamp * 2);
+			}
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IStatable.cs

@@ -0,0 +1,31 @@
+using System.IO;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : IStatable
+	{
+		public bool AvoidRewind => false;
+
+		public void LoadStateBinary(BinaryReader reader)
+		{
+			_elf.LoadStateBinary(reader);
+			// other variables
+			_frame = reader.ReadInt32();
+			LagCount = reader.ReadInt32();
+			IsLagFrame = reader.ReadBoolean();
+			// any managed pointers that we sent to the core need to be resent now!
+			Core.stella_set_input_callback(_inputCallback);
+			UpdateVideo();
+		}
+
+		public void SaveStateBinary(BinaryWriter writer)
+		{
+			_elf.SaveStateBinary(writer);
+			// other variables
+			writer.Write(Frame);
+			writer.Write(LagCount);
+			writer.Write(IsLagFrame);
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.IVideoProvider.cs

@@ -0,0 +1,81 @@
+using BizHawk.Emulation.Common;
+using BizHawk.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella : IVideoProvider
+	{
+		public int[] GetVideoBuffer() => _vidBuff;
+
+		public int VirtualWidth => 160;
+
+		public int VirtualHeight => 192;
+
+		public int BufferWidth => _vwidth;
+
+		public int BufferHeight => _vheight;
+
+		public int BackgroundColor => unchecked((int)0xff000000);
+
+		public int VsyncNumerator { get; }
+
+		public int VsyncDenominator { get; }
+
+		private int[] _vidBuff = new int[0];
+		private int _vwidth;
+		private int _vheight;
+
+		private void UpdateVideoInitial()
+		{
+			// hack: you should call update_video() here, but that gives you 256x192 on frame 0
+			// and we know that we only use GPGX to emulate genesis games that will always be 320x224 immediately afterwards
+
+			// so instead, just assume a 320x224 size now; if that happens to be wrong, it'll be fixed soon enough.
+
+			_vwidth = 320;
+			_vheight = 224;
+			_vidBuff = new int[_vwidth * _vheight];
+			for (int i = 0; i < _vidBuff.Length; i++)
+			{
+				_vidBuff[i] = unchecked((int)0xff000000);
+			}
+		}
+
+		private readonly byte[] TwoBitToEightBitTable = new byte[] { 0, 85, 171, 255 };
+		private readonly byte[] ThreeBitToEightBitTable = new byte[] { 0, 36, 73, 109, 146, 182, 219, 255 };
+
+		private unsafe void UpdateVideo()
+		{
+			if (Frame == 0)
+			{
+				UpdateVideoInitial();
+				return;
+			}
+
+			using (_elf.EnterExit())
+			{
+				IntPtr src = IntPtr.Zero;
+
+				Core.stella_get_video(out var width, out var height, out var pitch, ref src);
+
+                _vwidth = width;
+				_vheight = height;
+			 
+			    byte* buffer = (byte*)src.ToPointer();
+
+				if (_vidBuff.Length < _vwidth * _vheight)
+					_vidBuff = new int[_vwidth * _vheight];
+
+                if (Region == DisplayType.NTSC)
+				 for (int i = 0; i < _vidBuff.Length; i++) _vidBuff[i] = NTSCPalette[buffer[i]];
+				
+				if (Region == DisplayType.PAL)
+				 for (int i = 0; i < _vidBuff.Length; i++) _vidBuff[i] = PALPalette[buffer[i]];
+
+				if (Region == DisplayType.SECAM)
+				 for (int i = 0; i < _vidBuff.Length; i++) _vidBuff[i] = SecamPalette[buffer[i]];
+			}
+		}
+
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.Pallete.cs

@@ -0,0 +1,207 @@
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public partial class Stella
+	{
+		private static readonly int[] PALPalette =
+		{
+			0x000000, 0x000000, 0x2b2b2b, 0x2b2b2b,
+			0x525252, 0x525252, 0x767676, 0x767676,
+			0x979797, 0x979797, 0xb6b6b6, 0xb6b6b6,
+			0xd2d2d2, 0xd2d2d2, 0xececec, 0xececec,
+
+			0x000000, 0x000000, 0x2b2b2b, 0x2b2b2b,
+			0x525252, 0x525252, 0x767676, 0x767676,
+			0x979797, 0x979797, 0xb6b6b6, 0xb6b6b6,
+			0xd2d2d2, 0xd2d2d2, 0xececec, 0xececec,
+
+			0x805800, 0x000000, 0x96711a, 0x2b2b2b,
+			0xab8732, 0x525252, 0xbe9c48, 0x767676,
+			0xcfaf5c, 0x979797, 0xdfc06f, 0xb6b6b6,
+			0xeed180, 0xd2d2d2, 0xfce090, 0xececec,
+
+			0x445c00, 0x000000, 0x5e791a, 0x2b2b2b,
+			0x769332, 0x525252, 0x8cac48, 0x767676,
+			0xa0c25c, 0x979797, 0xb3d76f, 0xb6b6b6,
+			0xc4ea80, 0xd2d2d2, 0xd4fc90, 0xececec,
+
+			0x703400, 0x000000, 0x89511a, 0x2b2b2b,
+			0xa06b32, 0x525252, 0xb68448, 0x767676,
+			0xc99a5c, 0x979797, 0xdcaf6f, 0xb6b6b6,
+			0xecc280, 0xd2d2d2, 0xfcd490, 0xececec,
+
+			0x006414, 0x000000, 0x1a8035, 0x2b2b2b,
+			0x329852, 0x525252, 0x48b06e, 0x767676,
+			0x5cc587, 0x979797, 0x6fd99e, 0xb6b6b6,
+			0x80ebb4, 0xd2d2d2, 0x90fcc8, 0xececec,
+
+			0x700014, 0x000000, 0x891a35, 0x2b2b2b,
+			0xa03252, 0x525252, 0xb6486e, 0x767676,
+			0xc95c87, 0x979797, 0xdc6f9e, 0xb6b6b6,
+			0xec80b4, 0xd2d2d2, 0xfc90c8, 0xececec,
+
+			0x005c5c, 0x000000, 0x1a7676, 0x2b2b2b,
+			0x328e8e, 0x525252, 0x48a4a4, 0x767676,
+			0x5cb8b8, 0x979797, 0x6fcbcb, 0xb6b6b6,
+			0x80dcdc, 0xd2d2d2, 0x90ecec, 0xececec,
+
+			0x70005c, 0x000000, 0x841a74, 0x2b2b2b,
+			0x963289, 0x525252, 0xa8489e, 0x767676,
+			0xb75cb0, 0x979797, 0xc66fc1, 0xb6b6b6,
+			0xd380d1, 0xd2d2d2, 0xe090e0, 0xececec,
+
+			0x003c70, 0x000000, 0x195a89, 0x2b2b2b,
+			0x2f75a0, 0x525252, 0x448eb6, 0x767676,
+			0x57a5c9, 0x979797, 0x68badc, 0xb6b6b6,
+			0x79ceec, 0xd2d2d2, 0x88e0fc, 0xececec,
+
+			0x580070, 0x000000, 0x6e1a89, 0x2b2b2b,
+			0x8332a0, 0x525252, 0x9648b6, 0x767676,
+			0xa75cc9, 0x979797, 0xb76fdc, 0xb6b6b6,
+			0xc680ec, 0xd2d2d2, 0xd490fc, 0xececec,
+
+			0x002070, 0x000000, 0x193f89, 0x2b2b2b,
+			0x2f5aa0, 0x525252, 0x4474b6, 0x767676,
+			0x578bc9, 0x979797, 0x68a1dc, 0xb6b6b6,
+			0x79b5ec, 0xd2d2d2, 0x88c8fc, 0xececec,
+
+			0x340080, 0x000000, 0x4a1a96, 0x2b2b2b,
+			0x5f32ab, 0x525252, 0x7248be, 0x767676,
+			0x835ccf, 0x979797, 0x936fdf, 0xb6b6b6,
+			0xa280ee, 0xd2d2d2, 0xb090fc, 0xececec,
+
+			0x000088, 0x000000, 0x1a1a9d, 0x2b2b2b,
+			0x3232b0, 0x525252, 0x4848c2, 0x767676,
+			0x5c5cd2, 0x979797, 0x6f6fe1, 0xb6b6b6,
+			0x8080ef, 0xd2d2d2, 0x9090fc, 0xececec,
+
+			0x000000, 0x000000, 0x2b2b2b, 0x2b2b2b,
+			0x525252, 0x525252, 0x767676, 0x767676,
+			0x979797, 0x979797, 0xb6b6b6, 0xb6b6b6,
+			0xd2d2d2, 0xd2d2d2, 0xececec, 0xececec,
+
+			0x000000, 0x000000, 0x2b2b2b, 0x2b2b2b,
+			0x525252, 0x525252, 0x767676, 0x767676,
+			0x979797, 0x979797, 0xb6b6b6, 0xb6b6b6,
+			0xd2d2d2, 0xd2d2d2, 0xececec, 0xececec
+		};
+
+		private static readonly int[] NTSCPalette =
+		{
+			0x000000, 0, 0x4a4a4a, 0, 0x6f6f6f, 0, 0x8e8e8e, 0,
+			0xaaaaaa, 0, 0xc0c0c0, 0, 0xd6d6d6, 0, 0xececec, 0,
+			0x484800, 0, 0x69690f, 0, 0x86861d, 0, 0xa2a22a, 0,
+			0xbbbb35, 0, 0xd2d240, 0, 0xe8e84a, 0, 0xfcfc54, 0,
+			0x7c2c00, 0, 0x904811, 0, 0xa26221, 0, 0xb47a30, 0,
+			0xc3903d, 0, 0xd2a44a, 0, 0xdfb755, 0, 0xecc860, 0,
+			0x901c00, 0, 0xa33915, 0, 0xb55328, 0, 0xc66c3a, 0,
+			0xd5824a, 0, 0xe39759, 0, 0xf0aa67, 0, 0xfcbc74, 0,
+			0x940000, 0, 0xa71a1a, 0, 0xb83232, 0, 0xc84848, 0,
+			0xd65c5c, 0, 0xe46f6f, 0, 0xf08080, 0, 0xfc9090, 0,
+			0x840064, 0, 0x97197a, 0, 0xa8308f, 0, 0xb846a2, 0,
+			0xc659b3, 0, 0xd46cc3, 0, 0xe07cd2, 0, 0xec8ce0, 0,
+			0x500084, 0, 0x68199a, 0, 0x7d30ad, 0, 0x9246c0, 0,
+			0xa459d0, 0, 0xb56ce0, 0, 0xc57cee, 0, 0xd48cfc, 0,
+			0x140090, 0, 0x331aa3, 0, 0x4e32b5, 0, 0x6848c6, 0,
+			0x7f5cd5, 0, 0x956fe3, 0, 0xa980f0, 0, 0xbc90fc, 0,
+			0x000094, 0, 0x181aa7, 0, 0x2d32b8, 0, 0x4248c8, 0,
+			0x545cd6, 0, 0x656fe4, 0, 0x7580f0, 0, 0x8490fc, 0,
+			0x001c88, 0, 0x183b9d, 0, 0x2d57b0, 0, 0x4272c2, 0,
+			0x548ad2, 0, 0x65a0e1, 0, 0x75b5ef, 0, 0x84c8fc, 0,
+			0x003064, 0, 0x185080, 0, 0x2d6d98, 0, 0x4288b0, 0,
+			0x54a0c5, 0, 0x65b7d9, 0, 0x75cceb, 0, 0x84e0fc, 0,
+			0x004030, 0, 0x18624e, 0, 0x2d8169, 0, 0x429e82, 0,
+			0x54b899, 0, 0x65d1ae, 0, 0x75e7c2, 0, 0x84fcd4, 0,
+			0x004400, 0, 0x1a661a, 0, 0x328432, 0, 0x48a048, 0,
+			0x5cba5c, 0, 0x6fd26f, 0, 0x80e880, 0, 0x90fc90, 0,
+			0x143c00, 0, 0x355f18, 0, 0x527e2d, 0, 0x6e9c42, 0,
+			0x87b754, 0, 0x9ed065, 0, 0xb4e775, 0, 0xc8fc84, 0,
+			0x303800, 0, 0x505916, 0, 0x6d762b, 0, 0x88923e, 0,
+			0xa0ab4f, 0, 0xb7c25f, 0, 0xccd86e, 0, 0xe0ec7c, 0,
+			0x482c00, 0, 0x694d14, 0, 0x866a26, 0, 0xa28638, 0,
+			0xbb9f47, 0, 0xd2b656, 0, 0xe8cc63, 0, 0xfce070, 0
+		};
+
+		private static readonly int[] SecamPalette =
+		{
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff,
+
+			0x000000, 0x000000, 0x2121FF, 0x2121FF,
+			0xF03C79, 0xF03C79, 0xFF50FF, 0xFF50FF,
+			0x7FFF00, 0x7FFF00, 0x7FFFFF, 0x7FFFFF,
+			0xFFFF3F, 0xFFFF3F, 0xffffff, 0xffffff
+		};
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/Stella.cs

@@ -0,0 +1,185 @@
+using System.Linq;
+using System.Runtime.InteropServices;
+using BizHawk.BizInvoke;
+using BizHawk.Common;
+using BizHawk.Common.PathExtensions;
+using BizHawk.Emulation.Common;
+using BizHawk.Emulation.Cores.Consoles.Atari.Stella;
+using BizHawk.Emulation.Cores.Waterbox;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	[PortedCore(
+		name: CoreNames.Stella,
+		author: "The Stella Team",
+//		portedVersion: "", //TODO
+		portedUrl: "https://stella-emu.github.io")]
+	[ServiceNotApplicable(new[] { typeof(IDriveLight), typeof(ISaveRam) })]
+	public partial class Stella : IEmulator, IVideoProvider, IInputPollable, IRomInfo, IRegionable,
+		ICreateGameDBEntries, ISettable<Stella.A2600Settings, Stella.A2600SyncSettings>
+	{
+		internal static class RomChecksums
+		{
+			public const string CongoBongo = "SHA1:3A77DB43B6583E8689435F0F14AA04B9E57BDDED";
+
+			public const string KangarooNotInGameDB = "SHA1:982B8016B393A9AA7DD110295A53C4612ECF2141";
+
+			public const string Tapper = "SHA1:E986E1818E747BEB9B33CE4DFF1CDC6B55BDB620";
+		}
+
+		[CoreConstructor(VSystemID.Raw.A26)]
+		public Stella(CoreLoadParameters<Stella.A2600Settings, Stella.A2600SyncSettings> lp)
+		{
+			var ser = new BasicServiceProvider(this);
+			ServiceProvider = ser;
+			SyncSettings = lp.SyncSettings ?? new A2600SyncSettings();
+			Settings = lp.Settings ?? new A2600Settings();
+			_controllerDeck = new Atari2600ControllerDeck(SyncSettings.Port1, SyncSettings.Port2);
+
+			_elf = new WaterboxHost(new WaterboxOptions
+			{
+				Path = PathUtils.DllDirectoryPath,
+				Filename = "stella.wbx",
+				SbrkHeapSizeKB = 4 * 1024,
+				SealedHeapSizeKB = 4 * 1024,
+				InvisibleHeapSizeKB = 4 * 1024,
+				PlainHeapSizeKB = 4 * 1024,
+				MmapHeapSizeKB = 4 * 1024,
+				SkipCoreConsistencyCheck = lp.Comm.CorePreferences.HasFlag(CoreComm.CorePreferencesFlags.WaterboxCoreConsistencyCheck),
+				SkipMemoryConsistencyCheck = lp.Comm.CorePreferences.HasFlag(CoreComm.CorePreferencesFlags.WaterboxMemoryConsistencyCheck),
+			});
+
+			LoadCallback = load_archive;
+			_inputCallback = input_callback;
+
+			var callingConventionAdapter = CallingConventionAdapters.MakeWaterbox(new Delegate[]
+			{
+				LoadCallback, _inputCallback
+			}, _elf);
+
+			using (_elf.EnterExit())
+			{
+				Core = BizInvoker.GetInvoker<CInterface>(_elf, _elf, callingConventionAdapter);
+				SyncSettings = lp.SyncSettings ?? new A2600SyncSettings();
+				Settings = lp.Settings ?? new A2600Settings();
+
+				CoreComm = lp.Comm;
+
+				_romfile = lp.Roms.FirstOrDefault()?.RomData;
+				string romPath = lp.Roms.FirstOrDefault()?.RomPath;
+
+				var initResult = Core.stella_init(romPath, LoadCallback, SyncSettings.GetNativeSettings(lp.Game));
+
+				if (!initResult) throw new Exception($"{nameof(Core.stella_init)}() failed");
+
+				Core.stella_get_frame_rate(out int fps);
+
+				int regionId = Core.stella_get_region();
+				if (regionId == 0) _region = DisplayType.NTSC;
+				if (regionId == 1) _region = DisplayType.PAL;
+				if (regionId == 2) _region = DisplayType.SECAM;
+
+				VsyncNumerator = fps;
+				VsyncDenominator = 1;
+
+				Core.stella_set_input_callback(_inputCallback);
+
+				// Getting cartridge type
+				var ptr = Core.stella_get_cart_type();
+				string _cartType = Marshal.PtrToStringAnsi(ptr);
+				Console.WriteLine("[Stella] Cart type loaded: {0} (string size: {1}, ptr: {2})", _cartType, _cartType.Length, ptr);
+
+				_elf.Seal();
+			}
+
+			// pull the default video size from the core
+			UpdateVideo();
+
+			// Registering memory domains
+			SetupMemoryDomains();
+		}
+
+		// IRegionable
+		public DisplayType Region => _region;
+
+		private DisplayType _region;
+
+		private CInterface.load_archive_cb LoadCallback;
+
+		private readonly byte[] _romfile;
+		private readonly CInterface Core;
+		private readonly WaterboxHost _elf;
+		private string _cartType { get; }
+
+		private CoreComm CoreComm { get; }
+
+		public string RomDetails { get; private set; }
+
+		private readonly Atari2600ControllerDeck _controllerDeck;
+
+		private ITraceable Tracer { get; }
+
+		// ICreateGameDBEntries
+		public CompactGameInfo GenerateGameDbEntry()
+		{
+			return new CompactGameInfo
+			{
+			};
+		}
+
+		// IBoardInfo
+		private static bool DetectPal(GameInfo game, byte[] rom)
+		{
+			return true;
+		}
+
+		/// <summary>
+		/// core callback for file loading
+		/// </summary>
+		/// <param name="filename">string identifying file to be loaded</param>
+		/// <param name="buffer">buffer to load file to</param>
+		/// <param name="maxsize">maximum length buffer can hold</param>
+		/// <returns>actual size loaded, or 0 on failure</returns>
+		private int load_archive(string filename, IntPtr buffer, int maxsize)
+		{
+			byte[] srcdata = null;
+
+			if (buffer == IntPtr.Zero)
+			{
+				Console.WriteLine("Couldn't satisfy firmware request {0} because buffer == NULL", filename);
+				return 0;
+			}
+
+			if (filename == "PRIMARY_ROM")
+			{
+				if (_romfile == null)
+				{
+					Console.WriteLine("Couldn't satisfy firmware request PRIMARY_ROM because none was provided.");
+					return 0;
+				}
+				srcdata = _romfile;
+			}
+
+			if (srcdata != null)
+			{
+				if (srcdata.Length > maxsize)
+				{
+					Console.WriteLine("Couldn't satisfy firmware request {0} because {1} > {2}", filename, srcdata.Length, maxsize);
+					return 0;
+				}
+				else
+				{
+					Console.WriteLine("Copying Data from " + srcdata + " to " + buffer + " Size: " + srcdata.Length);
+					Marshal.Copy(srcdata, 0, buffer, srcdata.Length);
+					Console.WriteLine("Firmware request {0} satisfied at size {1}", filename, srcdata.Length);
+					return srcdata.Length;
+				}
+			}
+			else
+			{
+				throw new InvalidOperationException("Unknown error processing firmware");
+			}
+
+		}
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/StellaControllerDeck.cs

@@ -0,0 +1,83 @@
+using System.Collections.Generic;
+using System.Linq;
+
+using BizHawk.Common;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public class Atari2600ControllerDeck
+	{
+
+		public Atari2600ControllerDeck(Atari2600ControllerTypes controller1, Atari2600ControllerTypes controller2)
+		{
+			Port1 = ControllerCtors[controller1](1);
+			Port2 = ControllerCtors[controller2](2);
+
+			Definition = new("Atari 2600 Basic Controller")
+			{
+				BoolButtons = Port1.Definition.BoolButtons
+					.Concat(Port2.Definition.BoolButtons)
+					.Concat(new[]
+					{
+						"Reset", "Select", "Power", "Toggle Left Difficulty", "Toggle Right Difficulty"
+					})
+					.ToList()
+			};
+
+			foreach (var kvp in Port1.Definition.Axes) Definition.Axes.Add(kvp);
+			foreach (var kvp in Port2.Definition.Axes) Definition.Axes.Add(kvp);
+
+			Definition.MakeImmutable();
+		}
+
+		public byte ReadPort1(IController c)
+		{
+			return Port1.Read(c);
+		}
+
+		public byte ReadPort2(IController c)
+		{
+			return Port2.Read(c);
+		}
+
+		public int ReadPot1(IController c, int pot)
+		{
+			return Port1.Read_Pot(c, pot);
+		}
+
+		public int ReadPot2(IController c, int pot)
+		{
+			return Port2.Read_Pot(c, pot);
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			ser.BeginSection(nameof(Port1));
+			Port1.SyncState(ser);
+			ser.EndSection();
+
+			ser.BeginSection(nameof(Port2));
+			Port2.SyncState(ser);
+			ser.EndSection();
+		}
+
+		private readonly IPort Port1;
+		private readonly IPort Port2;
+
+		private static IReadOnlyDictionary<Atari2600ControllerTypes, Func<int, IPort>> _controllerCtors;
+
+		public static IReadOnlyDictionary<Atari2600ControllerTypes, Func<int, IPort>> ControllerCtors => _controllerCtors
+			??= new Dictionary<Atari2600ControllerTypes, Func<int, IPort>>
+			{
+				[Atari2600ControllerTypes.Unplugged] = portNum => new UnpluggedController(portNum),
+				[Atari2600ControllerTypes.Joystick] = portNum => new StandardController(portNum),
+				[Atari2600ControllerTypes.Paddle] = portNum => new PaddleController(portNum),
+				[Atari2600ControllerTypes.BoostGrip] = portNum => new BoostGripController(portNum),
+				[Atari2600ControllerTypes.Driving] = portNum => new DrivingController(portNum),
+				[Atari2600ControllerTypes.Keyboard] = portNum => new KeyboardController(portNum)
+			};
+	}
+}

src/BizHawk.Emulation.Cores/Consoles/Atari/Stella/StellaControllers.cs

@@ -0,0 +1,375 @@
+using System.Linq;
+
+using BizHawk.Common;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Emulation.Cores.Atari.Stella
+{
+	public enum Atari2600ControllerTypes
+	{
+		Unplugged,
+		Joystick,
+		Paddle,
+		BoostGrip,
+		Driving,
+		Keyboard
+	}
+
+	/// <summary>
+	/// Represents a controller plugged into a controller port on the 2600
+	/// </summary>
+	public interface IPort
+	{
+		byte Read(IController c);
+
+		int Read_Pot(IController c, int pot);
+
+		ControllerDefinition Definition { get; }
+
+		void SyncState(Serializer ser);
+
+		int PortNum { get; }
+	}
+
+	public class UnpluggedController : IPort
+	{
+		public UnpluggedController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new("(Atari 2600 Basic Controller fragment)");
+		}
+
+		public byte Read(IController c)
+		{
+			return 0xFF;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			return -1; // indicates not applicable
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Do nothing
+		}
+
+		public int PortNum { get; }
+	}
+
+	public class StandardController : IPort
+	{
+		public StandardController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new("(Atari 2600 Basic Controller fragment)")
+			{
+				BoolButtons = BaseDefinition
+				.Select(b => $"P{PortNum} " + b)
+				.ToList()
+			};
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Nothing todo, I think
+		}
+
+		public int PortNum { get; }
+
+		public byte Read(IController c)
+		{
+			byte result = 0xFF;
+
+			if (c.IsPressed($"P{PortNum} Up")) { result &= 0xEF; }
+			if (c.IsPressed($"P{PortNum} Down")) { result &= 0xDF; }
+			if (c.IsPressed($"P{PortNum} Left")) { result &= 0xBF; }
+			if (c.IsPressed($"P{PortNum} Right")) { result &= 0x7F; }
+			if (c.IsPressed($"P{PortNum} Button")) { result &= 0xF7; }
+
+			return result;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			return -1; // indicates not applicable
+		}
+
+		private static readonly string[] BaseDefinition =
+		{
+			"Up", "Down", "Left", "Right", "Button"
+		};
+	}
+
+	public class PaddleController : IPort
+	{
+		public PaddleController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new ControllerDefinition("(Atari 2600 Basic Controller fragment)")
+			{
+				BoolButtons = BaseDefinition
+				.Select(b => $"P{PortNum} " + b)
+				.ToList()
+			}.AddAxis($"P{PortNum} Paddle X 1", (-127).RangeTo(127), 0)
+				.AddAxis($"P{PortNum} Paddle X 2", (-127).RangeTo(127), 0)
+				.MakeImmutable();
+		}
+
+		public int PortNum { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Nothing todo, I think
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		private static readonly string[] BaseDefinition =
+		{
+			"Button 1",
+			"Button 2"
+		};
+
+		public byte Read(IController c)
+		{
+			byte result = 0xF0;
+
+			if (c.IsPressed($"P{PortNum} Button 1")) { result &= 0x70; }
+			if (c.IsPressed($"P{PortNum} Button 2")) { result &= 0xB0; }
+
+			return result;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			int x = c.AxisValue(Definition.Axes[pot]);
+			
+			x = -x;
+			x += 127;
+
+			x = x * 64 + 10;
+
+			return x;
+		}
+	}
+
+	public class BoostGripController : IPort
+	{
+		public BoostGripController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new("(Atari 2600 Basic Controller fragment)")
+			{
+				BoolButtons = BaseDefinition
+				.Select(b => $"P{PortNum} " + b)
+				.ToList()
+			};
+		}
+
+		public int PortNum { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Nothing todo, I think
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		private static readonly string[] BaseDefinition =
+		{
+			"Up", "Down", "Left", "Right", "Button",
+			"Button 1",
+			"Button 2"
+		};
+
+		public byte Read(IController c)
+		{
+			byte result = 0xFF;
+
+			if (c.IsPressed($"P{PortNum} Up")) { result &= 0xEF; }
+			if (c.IsPressed($"P{PortNum} Down")) { result &= 0xDF; }
+			if (c.IsPressed($"P{PortNum} Left")) { result &= 0xBF; }
+			if (c.IsPressed($"P{PortNum} Right")) { result &= 0x7F; }
+			if (c.IsPressed($"P{PortNum} Button")) { result &= 0xF7; }
+
+			return result;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			bool is_pressed = false;
+
+			if (pot == 0)
+			{
+				is_pressed = c.IsPressed($"P{PortNum} Button 1");
+			}
+			else
+			{
+				is_pressed = c.IsPressed($"P{PortNum} Button 2");
+			}
+			
+			if (is_pressed)
+			{
+				return 10;
+			}
+
+			return 65535;
+		}
+	}
+
+	public class DrivingController : IPort
+	{
+		public DrivingController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new ControllerDefinition("(Atari 2600 Basic Controller fragment)")
+			{
+				BoolButtons = BaseDefinition
+				.Select(b => $"P{PortNum} " + b)
+				.ToList()
+			}.AddAxis($"P{PortNum} Wheel X 1", (-127).RangeTo(127), 0)
+				.AddAxis($"P{PortNum} Wheel X 2", (-127).RangeTo(127), 0)
+				.MakeImmutable();
+		}
+
+		public int PortNum { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Nothing todo, I think
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		private static readonly string[] BaseDefinition =
+		{
+			"Button"
+		};
+
+		public byte Read(IController c)
+		{
+			byte result = 0xFF;
+
+			if (c.IsPressed($"P{PortNum} Button")) { result &= 0xF7; }
+
+			float x = c.AxisValue(Definition.Axes[0]);
+			float y = c.AxisValue(Definition.Axes[1]);
+
+			float angle = CalcDirection(x, y);
+
+			byte temp2 = 0;
+
+			int temp1 = (int)Math.Floor(angle / 45);
+			temp1 %= 4;
+
+			if (temp1 == 0)
+			{
+				temp2 = 0xEF;
+			}
+
+			if (temp1 == 1)
+			{
+				temp2 = 0xCF;
+			}
+			if (temp1 == 2)
+			{
+				temp2 = 0xDF;
+			}
+
+			if (temp1 == 3)
+			{
+				temp2 = 0xFF;
+			}
+
+
+			result &= temp2;
+
+
+			return result;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			return -1;  // indicates not applicable
+		}
+
+		private static float CalcDirection(float x, float y)
+		{
+			y = -y; // vflip to match the arrangement of FloatControllerButtons
+
+			// the wheel is arranged in a grey coded configuration of sensitivity ~2.5 degrees
+			// for each signal
+			// so overall the value returned changes every 1.25 degrees
+
+			float angle = (float)(Math.Atan2(y, x) * 180.0 / Math.PI);
+
+			if (angle < 0)
+			{
+				angle = 360 + angle;
+			}
+
+			return angle;
+		}
+	}
+
+	public class KeyboardController : IPort
+	{
+		public KeyboardController(int portNum)
+		{
+			PortNum = portNum;
+			Definition = new("(Atari 2600 Basic Controller fragment)")
+			{
+				BoolButtons = BaseDefinition
+				.Select(b => $"P{PortNum} " + b)
+				.ToList()
+			};
+		}
+
+		public ControllerDefinition Definition { get; }
+
+		public void SyncState(Serializer ser)
+		{
+			// Nothing todo, I think
+		}
+
+		public int PortNum { get; }
+
+		public byte Read(IController c)
+		{
+			byte result = 0xFF;
+
+			if (c.IsPressed($"P{PortNum} 0")) { result = 0x00; }
+			if (c.IsPressed($"P{PortNum} 1")) { result = 0x01; }
+			if (c.IsPressed($"P{PortNum} 2")) { result = 0x02; }
+			if (c.IsPressed($"P{PortNum} 3")) { result = 0x03; }
+			if (c.IsPressed($"P{PortNum} 4")) { result = 0x04; }
+			if (c.IsPressed($"P{PortNum} 5")) { result = 0x05; }
+			if (c.IsPressed($"P{PortNum} 6")) { result = 0x06; }
+			if (c.IsPressed($"P{PortNum} 7")) { result = 0x07; }
+			if (c.IsPressed($"P{PortNum} 8")) { result = 0x08; }
+			if (c.IsPressed($"P{PortNum} 9")) { result = 0x09; }
+			if (c.IsPressed($"P{PortNum} *")) { result = 0x0A; }
+			if (c.IsPressed($"P{PortNum} #")) { result = 0x0B; }
+
+			return result;
+		}
+
+		public int Read_Pot(IController c, int pot)
+		{
+			return -2; // indicates keyboard
+		}
+
+		private static readonly string[] BaseDefinition =
+		{
+			"1", "2", "3",
+			"4", "5", "6",
+			"7", "8", "9",
+			"*", "0", "#"
+		};
+	}
+}

src/BizHawk.Emulation.Cores/CoreNames.cs

@@ -52,6 +52,7 @@ namespace BizHawk.Emulation.Cores
 		public const string Saturnus = "Saturnus";
 		public const string SMSHawk = "SMSHawk";
 		public const string Snes9X = "Snes9x";
+		public const string Stella = "Stella";
 		public const string SubBsnes115 = "SubBSNESv115+";
 		public const string SubGbHawk = "SubGBHawk";
 		public const string SubNesHawk = "SubNESHawk";

waterbox/common.mak

@@ -46,8 +46,14 @@ CXXFLAGS_RELEASE := -O3 -flto -DNDEBUG
 CXXFLAGS_RELEASE_ASONLY := -O3
 
 EXTRA_LIBS := -L $(SYSROOT)/lib/linux -lclang_rt.builtins-x86_64 $(EXTRA_LIBS)
+CPP_EXTRA_LIBS := -lc++ -lc++abi -lunwind $(EXTRA_LIBS)
+
 ifneq ($(filter %.cpp,$(SRCS)),)
-EXTRA_LIBS := -lc++ -lc++abi -lunwind $(EXTRA_LIBS)
+EXTRA_LIBS += $(CPP_EXTRA_LIBS)
+endif
+
+ifneq ($(filter %.cxx,$(SRCS)),)
+EXTRA_LIBS += $(CPP_EXTRA_LIBS)
 endif
 
 _OBJS := $(addsuffix .o,$(abspath $(SRCS)))
@@ -62,6 +68,10 @@ $(OBJ_DIR)/%.cpp.o: %.cpp
 	@echo cxx $<
 	@mkdir -p $(@D)
 	@$(CC) -c -o $@ $< $(CXXFLAGS) $(CXXFLAGS_RELEASE) $(PER_FILE_FLAGS_$<)
+$(OBJ_DIR)/%.cxx.o: %.cxx
+	@echo cxx $<
+	@mkdir -p $(@D)
+	@$(CC) -c -o $@ $< $(CXXFLAGS) $(CXXFLAGS_RELEASE) $(PER_FILE_FLAGS_$<)
 $(DOBJ_DIR)/%.c.o: %.c
 	@echo cc $<
 	@mkdir -p $(@D)
@@ -70,6 +80,10 @@ $(DOBJ_DIR)/%.cpp.o: %.cpp
 	@echo cxx $<
 	@mkdir -p $(@D)
 	@$(CC) -c -o $@ $< $(CXXFLAGS) $(CXXFLAGS_DEBUG) $(PER_FILE_FLAGS_$<)
+$(DOBJ_DIR)/%.cxx.o: %.cxx
+	@echo cxx $<
+	@mkdir -p $(@D)
+	@$(CC) -c -o $@ $< $(CXXFLAGS) $(CXXFLAGS_DEBUG) $(PER_FILE_FLAGS_$<)
 $(OBJ_DIR)/%.c.s: %.c
 	@echo cc -S $<
 	@mkdir -p $(@D)
@@ -78,6 +92,10 @@ $(OBJ_DIR)/%.cpp.s: %.cpp
 	@echo cxx -S $<
 	@mkdir -p $(@D)
 	@$(CC) -c -S -o $@ $< $(CXXFLAGS) $(CXXFLAGS_RELEASE_ASONLY) $(PER_FILE_FLAGS_$<)
+$(OBJ_DIR)/%.cxx.s: %.cxx
+	@echo cxx -S $<
+	@mkdir -p $(@D)
+	@$(CC) -c -S -o $@ $< $(CXXFLAGS) $(CXXFLAGS_RELEASE_ASONLY) $(PER_FILE_FLAGS_$<)
 
 ifndef NO_WBX_TARGETS
 

waterbox/make-all-cores.sh

@@ -9,6 +9,7 @@ cd gpgx && make -f Makefile $1 -j && cd -
 cd libsnes && make -f Makefile $1 -j && cd -
 cd melon && make -f Makefile $1 -j && cd -
 cd picodrive && make -f Makefile $1 -j && cd -
+cd stella && make -f Makefile $1 -j && cd -
 cd snes9x && make -f Makefile $1 -j && cd -
 cd tic80 && make -f Makefile $1 -j && cd -
 cd uae && make -f Makefile $1 -j && cd -

waterbox/readme.txt

@@ -37,6 +37,7 @@ It consists of a modified musl libc, and build scripts to tie it all together.
 		* waterbox/snes9x (required for Snes9x)
 		* waterbox/gpgx/Genesis-Plus-GX (required for gpgx)
 		* waterbox/uae/libretro-uae (required for puae)
+		* waterbox/stella/core (required for stella)
 	* none of these submodules need to be cloned recursively
 
 3. Consider whether it is time to update your build environment (i.e. sudo apt-get upgrade). Build environment tools are generally best kept at the latest version, to ensure top performance for our users.
@@ -76,6 +77,7 @@ It consists of a modified musl libc, and build scripts to tie it all together.
 	cd nyma && make -f shock.mak install
 	cd nyma && make -f vb.mak install
 	cd picodrive && make install
+	cd stella && make install
 	cd snes9x && make install
 	cd tic80 && make install
 	cd uae && make install

waterbox/stella/BizhawkInterface.cxx

@@ -0,0 +1,224 @@
+#include <cstdio>
+#include <cstdint>
+#include "Cart.hxx"
+#include "BizhawkInterface.hxx"
+#include "OSystem.hxx"
+#include "Settings.hxx"
+#include "MediaFactory.hxx"
+#include "Serializer.hxx"
+#include "StateManager.hxx"
+#include "Console.hxx"
+#include "Control.hxx"
+#include "Switches.hxx"
+#include "M6532.hxx"
+#include "TIA.hxx"
+
+#define SOUND_BUFFER_SIZE 1024*1024
+
+uint16_t* soundbuffer;
+int nsamples;
+
+struct InitSettings
+{
+	uint32_t dummy;
+};
+
+std::unique_ptr<OSystem> _a2600;
+
+void printRAM()
+{
+  printf("[] Ram Pointer: %p\n", _a2600->console().riot().getRAM());
+  printf("[] Memory Contents:\n");
+		for (int i = 0; i < 8; i++)
+		{
+			for (int j = 0; j < 16; j++)
+			{
+				printf("%02X ", _a2600->console().riot().getRAM()[i*16 + j]);
+			}
+			printf("\n");
+		}
+}
+
+enum regionType
+{
+   ntsc = 0,
+   pal = 1,
+			secam = 2
+};
+
+ECL_EXPORT int stella_get_region()
+{
+	const auto regionString = _a2600->console().getFormatString();
+
+		if (regionString == "NTSC" || regionString == "NTSC50") return regionType::ntsc;
+		if (regionString == "PAL" || regionString == "PAL60") return regionType::pal;
+		if (regionString == "SECAM" || regionString == "SECAM60") return regionType::secam;
+
+ 	return -1;
+}
+
+ECL_EXPORT void stella_get_frame_rate(int& fps)
+{
+	 fps = _a2600->console().gameRefreshRate();
+}
+
+void printFrameBuffer()
+{
+	 auto frameBuffer = _a2600->console().tia().frameBuffer();
+		auto height =   _a2600->console().tia().height();
+		auto width =   _a2600->console().tia().width();
+
+  printf("[] Frame Buffer Pointer: %p\n", frameBuffer);
+  // printf("[] Frame Buffer Contents:\n");
+
+		uint64_t checkSum = 0;
+		for (int i = 0; i < height; i++)
+		{
+			for (int j = 0; j < width; j++)
+			{
+				// printf("%02X ", frameBuffer[i*height + j]);
+				checkSum += frameBuffer[i*height + j];
+			}
+			// printf("\n");
+		}
+
+		printf("[] Frame Buffer Checksum: 0x%lX\n", checkSum);
+}
+
+ECL_EXPORT const char* stella_get_cart_type()
+{
+	return _a2600->console().cartridge().detectedType().c_str();
+}
+
+ECL_EXPORT uint8_t stella_peek_tia(uint32_t address)
+{
+ return _a2600->console().tia().peek(address);
+}
+
+ECL_EXPORT void stella_poke_tia(uint32_t address, uint8_t value)
+{
+ _a2600->console().tia().poke(address, value);
+}
+
+ECL_EXPORT uint8_t stella_peek_m6532(uint32_t address)
+{
+ return _a2600->console().riot().peek(address);
+}
+
+ECL_EXPORT void stella_poke_m6532(uint32_t address, uint8_t value)
+{
+ _a2600->console().riot().poke(address, value);
+}
+
+ECL_EXPORT uint8_t stella_peek_systembus(uint32_t address)
+{
+ return _a2600->console().system().peek(address);
+}
+
+ECL_EXPORT void stella_poke_systembus(uint32_t address, uint8_t value)
+{
+ _a2600->console().system().poke(address, value);
+}
+
+ECL_EXPORT uint32_t stella_get_cartram_size()
+{
+	 return _a2600->console().cartridge().internalRamSize();
+}
+
+ECL_EXPORT uint8_t stella_peek_cartram(uint32_t address)
+{
+ return _a2600->console().cartridge().peek(address);
+}
+
+ECL_EXPORT void stella_poke_cartram(uint32_t address, uint8_t value)
+{
+ _a2600->console().cartridge().poke(address, value);
+}
+
+ECL_EXPORT void stella_get_mainram_ptr(void** ptr)
+{
+ *ptr = (void*) _a2600->console().riot().getRAM();
+}
+
+ECL_EXPORT void stella_get_audio(int *n, void **buffer)
+{
+	if (n)
+		*n = nsamples;
+	if (buffer)
+		*buffer = soundbuffer;
+}
+
+ECL_EXPORT void stella_get_video(int& w, int& h, int& pitch, uint8_t*& buffer)
+{
+	 w = _a2600->console().tia().width();
+		h = _a2600->console().tia().height();
+		buffer = _a2600->console().tia().frameBuffer();
+	 pitch =	_a2600->console().tia().width();
+}
+
+
+ECL_EXPORT void stella_frame_advance(uint8_t port1, uint8_t port2, bool reset, bool power, bool leftDiffToggled, bool rightDiffToggled)
+{
+				_a2600->console().switches().setLeftDifficultyA(leftDiffToggled);
+    _a2600->console().switches().setRightDifficultyA(rightDiffToggled);
+				_a2600->console().switches().setReset(!reset);
+    if (power) _a2600->console().system().reset(true);
+
+				_a2600->console().leftController().write(::Controller::DigitalPin::One,   port1 & 0b00010000);  // Up
+				_a2600->console().leftController().write(::Controller::DigitalPin::Two,   port1 & 0b00100000);  // Down
+				_a2600->console().leftController().write(::Controller::DigitalPin::Three, port1 & 0b01000000);  // Left
+				_a2600->console().leftController().write(::Controller::DigitalPin::Four,  port1 & 0b10000000);  // Right
+				_a2600->console().leftController().write(::Controller::DigitalPin::Six,   port1 & 0b00001000);  // Button
+
+				_a2600->console().rightController().write(::Controller::DigitalPin::One,   port2 & 0b00010000);  // Up
+				_a2600->console().rightController().write(::Controller::DigitalPin::Two,   port2 & 0b00100000);  // Down
+				_a2600->console().rightController().write(::Controller::DigitalPin::Three, port2 & 0b01000000);  // Left
+				_a2600->console().rightController().write(::Controller::DigitalPin::Four,  port2 & 0b10000000);  // Right
+				_a2600->console().rightController().write(::Controller::DigitalPin::Six,   port2 & 0b00001000);  // Button
+
+				nsamples = 0;
+    _a2600->dispatchEmulation();
+				//  printRAM();
+				// printFrameBuffer();
+}
+
+ECL_ENTRY void (*input_callback_cb)(void);
+
+void real_input_callback(void)
+{
+	if (input_callback_cb)
+		input_callback_cb();
+}
+
+ECL_EXPORT void stella_set_input_callback(ECL_ENTRY void (*fecb)(void))
+{
+	input_callback_cb = fecb;
+}
+
+
+ECL_EXPORT int stella_init(
+	const char* romFileName,
+	ECL_ENTRY int (*feload_archive_cb)(const char *filename, unsigned char *buffer, int maxsize),
+	struct InitSettings *settings)
+{
+	fprintf(stderr, "Initializing Stella core...\n");
+ 
+ // Allocating sound buffer
+	soundbuffer = (uint16_t*) alloc_invisible(SOUND_BUFFER_SIZE);
+
+	Settings::Options opts;
+	_a2600 = MediaFactory::createOSystem();
+	if(!_a2600->initialize(opts)) { fprintf(stderr, "ERROR: Couldn't create A2600 System\n"); return 0; }
+
+	uint8_t* buf = (uint8_t*) calloc(1, BUFFER_SIZE);
+	int size = feload_archive_cb("PRIMARY_ROM", buf, BUFFER_SIZE);
+	const FSNode romnode(romFileName, buf, size);
+
+	auto error = _a2600->createConsole(romnode);
+	if (error != "") { fprintf(stderr, "ERROR: Couldn't create A2600 Console. Reason: '%s'\n", error.c_str()); return 0; }
+
+ printf("A2600 console created successfully\n");
+
+	return 1;
+}
+

waterbox/stella/BizhawkInterface.hxx

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <emulibc.h>
+#include <vector>
+#include <cstdint>
+
+extern uint16_t* soundbuffer;
+extern int nsamples;

waterbox/stella/Makefile

@@ -0,0 +1,200 @@
+STELLA_DIR := core
+
+CCFLAGS := \
+	-ISDL/include \
+	-ISDL/src
+
+CXXFLAGS := \
+	-I. \
+	-Iport \
+	-Icore/src/emucore \
+	-Icore/src/common \
+	-Icore/src/common/tv_filters \
+	-Icore/src/emucore/tia \
+	-Icore/src/emucore/tia/frame-manager \
+	-Icore/src/lib/json \
+	-Icore/src/common/repository/sqlite \
+	-Icore/src/os/unix \
+	-Icore/src/gui \
+	-Icore/src/lib/httplib \
+	-Icore/src/lib/sqlite \
+	-ISDL/include/SDL2 \
+	-ISDL/include \
+	-ISDL/src \
+	-DUNIX \
+	-DSOUND_SUPPORT \
+ -DSDL_ENABLE_OLD_NAMES \
+	-D_REENTRANT \
+	-D__USE_BIZHAWK \
+	-std=gnu++17 \
+	-Wno-multichar \
+
+LDFLAGS := 
+
+TARGET := stella.wbx
+
+SRCS = \
+	BizhawkInterface.cxx \
+ port/EventHandlerBizhawk.cxx \
+	port/FBBackendBizhawk.cxx \
+	port/FBSurfaceBizhawk.cxx \
+	port/OSystemBizhawk.cxx \
+	port/SoundBizhawk.cxx \
+	core/src/emucore/OSystem.cxx \
+	core/src/emucore/Switches.cxx \
+	core/src/emucore/FrameBuffer.cxx \
+	core/src/emucore/Console.cxx \
+	core/src/common/Logger.cxx \
+	core/src/common/tv_filters/NTSCFilter.cxx \
+	core/src/common/tv_filters/AtariNTSC.cxx \
+	core/src/common/AudioSettings.cxx \
+	core/src/common/VideoModeHandler.cxx \
+	core/src/common/PhysicalJoystick.cxx \
+	core/src/common/ThreadDebugging.cxx \
+	core/src/common/TimerManager.cxx \
+	core/src/common/PKeyboardHandler.cxx \
+	core/src/common/PhosphorHandler.cxx \
+	core/src/common/JoyMap.cxx \
+	core/src/common/ZipHandler.cxx \
+	core/src/common/MouseControl.cxx \
+	core/src/common/PJoystickHandler.cxx \
+	core/src/common/JPGLibrary.cxx \
+	core/src/common/AudioQueue.cxx \
+	core/src/common/StateManager.cxx \
+	core/src/common/DevSettingsHandler.cxx \
+	core/src/common/FpsMeter.cxx \
+	core/src/common/audio/ConvolutionBuffer.cxx \
+	core/src/common/audio/HighPass.cxx \
+	core/src/common/audio/SimpleResampler.cxx \
+	core/src/common/audio/LanczosResampler.cxx \
+	core/src/common/StaggeredLogger.cxx \
+	core/src/common/Base.cxx \
+	core/src/common/FSNodeZIP.cxx \
+	core/src/common/KeyMap.cxx \
+	core/src/common/repository/KeyValueRepositoryJsonFile.cxx \
+	core/src/common/repository/CompositeKVRJsonAdapter.cxx \
+	core/src/common/repository/sqlite/SqliteDatabase.cxx \
+	core/src/common/repository/sqlite/SqliteStatement.cxx \
+	core/src/common/repository/sqlite/SqliteTransaction.cxx \
+	core/src/common/repository/sqlite/AbstractKeyValueRepositorySqlite.cxx \
+	core/src/common/repository/sqlite/KeyValueRepositorySqlite.cxx \
+	core/src/common/repository/sqlite/StellaDb.cxx \
+	core/src/common/repository/sqlite/CompositeKeyValueRepositorySqlite.cxx \
+	core/src/common/repository/KeyValueRepositoryPropertyFile.cxx \
+	core/src/common/repository/CompositeKeyValueRepository.cxx \
+	core/src/common/repository/KeyValueRepositoryConfigfile.cxx \
+	core/src/common/Bezel.cxx \
+	core/src/common/PNGLibrary.cxx \
+	core/src/common/PaletteHandler.cxx \
+	core/src/common/RewindManager.cxx \
+	core/src/emucore/Genesis.cxx \
+	core/src/emucore/Bankswitch.cxx \
+	core/src/emucore/Cart03E0.cxx \
+	core/src/emucore/CartF0.cxx \
+	core/src/emucore/Cart4K.cxx \
+	core/src/emucore/CartWD.cxx \
+	core/src/emucore/Cart4A50.cxx \
+	core/src/emucore/CartBF.cxx \
+	core/src/emucore/EmulationWorker.cxx \
+	core/src/emucore/CartF6.cxx \
+	core/src/emucore/Cart.cxx \
+	core/src/emucore/CartF4SC.cxx \
+	core/src/emucore/CartCTY.cxx \
+	core/src/emucore/CartF8SC.cxx \
+	core/src/emucore/CartDetector.cxx \
+	core/src/emucore/CartDFSC.cxx \
+	core/src/emucore/Serializer.cxx \
+	core/src/emucore/Cart0840.cxx \
+	core/src/emucore/CartFA.cxx \
+	core/src/emucore/CartX07.cxx \
+	core/src/emucore/Cart2K.cxx \
+	core/src/emucore/Cart3EX.cxx \
+	core/src/emucore/CartDPCPlus.cxx \
+	core/src/emucore/CartBFSC.cxx \
+	core/src/emucore/CartCM.cxx \
+	core/src/emucore/CartEF.cxx \
+	core/src/emucore/CartSB.cxx \
+	core/src/emucore/MD5.cxx \
+	core/src/emucore/Settings.cxx \
+	core/src/emucore/CartBUS.cxx \
+	core/src/emucore/SaveKey.cxx \
+	core/src/emucore/CartDPC.cxx \
+	core/src/emucore/CompuMate.cxx \
+	core/src/emucore/TIASurface.cxx \
+	core/src/emucore/Paddles.cxx \
+	core/src/emucore/CartEFSC.cxx \
+	core/src/emucore/Joystick.cxx \
+	core/src/emucore/Lightgun.cxx \
+	core/src/emucore/KidVid.cxx \
+	core/src/emucore/CartAR.cxx \
+	core/src/emucore/CartFC.cxx \
+	core/src/emucore/Cart3F.cxx \
+	core/src/emucore/FBSurface.cxx \
+	core/src/emucore/Cart3E.cxx \
+	core/src/emucore/GlobalKeyHandler.cxx \
+	core/src/emucore/PointingDevice.cxx \
+	core/src/emucore/CartTVBoy.cxx \
+	core/src/emucore/CartCreator.cxx \
+	core/src/emucore/CartF6SC.cxx \
+	core/src/emucore/Cart4KSC.cxx \
+	core/src/emucore/Props.cxx \
+	core/src/emucore/Thumbulator.cxx \
+	core/src/emucore/DispatchResult.cxx \
+	core/src/emucore/EmulationTiming.cxx \
+	core/src/emucore/PlusROM.cxx \
+	core/src/emucore/CartGL.cxx \
+	core/src/emucore/Cart0FA0.cxx \
+	core/src/emucore/CartMVC.cxx \
+	core/src/emucore/Keyboard.cxx \
+	core/src/emucore/CartFA2.cxx \
+	core/src/emucore/QuadTari.cxx \
+	core/src/emucore/CartFE.cxx \
+	core/src/emucore/CartMDM.cxx \
+	core/src/emucore/CartF4.cxx \
+	core/src/emucore/CartF8.cxx \
+	core/src/emucore/CartCV.cxx \
+	core/src/emucore/EventHandler.cxx \
+	core/src/emucore/Driving.cxx \
+	core/src/emucore/M6532.cxx \
+	core/src/emucore/System.cxx \
+	core/src/emucore/M6502.cxx \
+	core/src/emucore/Joy2BPlus.cxx \
+	core/src/emucore/CartE7.cxx \
+	core/src/emucore/OSystemStandalone.cxx \
+	core/src/emucore/tia/Player.cxx \
+	core/src/emucore/tia/LatchedInput.cxx \
+	core/src/emucore/tia/Missile.cxx \
+	core/src/emucore/tia/frame-manager/FrameLayoutDetector.cxx \
+	core/src/emucore/tia/frame-manager/AbstractFrameManager.cxx \
+	core/src/emucore/tia/frame-manager/FrameManager.cxx \
+	core/src/emucore/tia/frame-manager/JitterEmulation.cxx \
+	core/src/emucore/tia/AnalogReadout.cxx \
+	core/src/emucore/tia/Background.cxx \
+	core/src/emucore/tia/DrawCounterDecodes.cxx \
+	core/src/emucore/tia/TIA.cxx \
+	core/src/emucore/tia/Playfield.cxx \
+	core/src/emucore/tia/Audio.cxx \
+	core/src/emucore/tia/AudioChannel.cxx \
+	core/src/emucore/tia/Ball.cxx \
+	core/src/emucore/CartARM.cxx \
+	core/src/emucore/PropsSet.cxx \
+	core/src/emucore/ProfilingRunner.cxx \
+	core/src/emucore/CartUA.cxx \
+	core/src/emucore/CartE0.cxx \
+	core/src/emucore/Booster.cxx \
+	core/src/emucore/CartEnhanced.cxx \
+	core/src/emucore/FSNode.cxx \
+	core/src/emucore/CartCDF.cxx \
+	core/src/emucore/ControllerDetector.cxx \
+	core/src/emucore/MindLink.cxx \
+	core/src/emucore/Cart3EPlus.cxx \
+	core/src/emucore/MT24LC256.cxx \
+	core/src/emucore/CartDF.cxx \
+	core/src/emucore/Control.cxx \
+	core/src/emucore/AtariVox.cxx \
+	core/src/os/unix/SerialPortUNIX.cxx \
+	core/src/lib/tinyexif/tinyexif.cxx \
+	core/src/lib/sqlite/sqlite3.c \
+	core/src/lib/nanojpeg/nanojpeg.c \
+
+include ../common.mak

waterbox/stella/core

@@ -0,0 +1 @@
+Subproject commit 48734d5c38c12e3988959ebcb6efee4a570268e3

waterbox/stella/port/EventHandlerBizhawk.cxx

@@ -0,0 +1,43 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#include "Logger.hxx"
+#include "OSystem.hxx"
+#include "EventHandlerBizhawk.hxx"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+EventHandlerBizhawk::EventHandlerBizhawk(OSystem& osystem)
+  : EventHandler{osystem}
+{
+
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+EventHandlerBizhawk::~EventHandlerBizhawk()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void EventHandlerBizhawk::enableTextEvents(bool enable)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void EventHandlerBizhawk::pollEvent()
+{
+}
+

waterbox/stella/port/EventHandlerBizhawk.hxx

@@ -0,0 +1,57 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#pragma once 
+
+#include "EventHandler.hxx"
+
+/**
+  This class handles event collection from the point of view of the specific
+  backend toolkit (Bizhawk).  It converts from Bizhawk-specific events into events
+  that the Stella core can understand.
+
+  @author  Stephen Anthony
+*/
+class EventHandlerBizhawk : public EventHandler
+{
+  public:
+    /**
+      Create a new Bizhawk event handler object
+    */
+    explicit EventHandlerBizhawk(OSystem& osystem);
+    ~EventHandlerBizhawk() override;
+
+  private:
+    /**
+      Enable/disable text events (distinct from single-key events).
+    */
+    void enableTextEvents(bool enable) override;
+
+    /**
+      Collects and dispatches any pending Bizhawk events.
+    */
+    void pollEvent() override;
+
+  private:
+    // Following constructors and assignment operators not supported
+    EventHandlerBizhawk() = delete;
+    EventHandlerBizhawk(const EventHandlerBizhawk&) = delete;
+    EventHandlerBizhawk(EventHandlerBizhawk&&) = delete;
+    EventHandlerBizhawk& operator=(const EventHandlerBizhawk&) = delete;
+    EventHandlerBizhawk& operator=(EventHandlerBizhawk&&) = delete;
+};
+

waterbox/stella/port/FBBackendBizhawk.cxx

@@ -0,0 +1,171 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#include <cmath>
+
+#include "bspf.hxx"
+#include "Logger.hxx"
+
+#include "Console.hxx"
+#include "OSystem.hxx"
+#include "Settings.hxx"
+
+#include "ThreadDebugging.hxx"
+#include "FBSurfaceBizhawk.hxx"
+#include "FBBackendBizhawk.hxx"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+FBBackendBIZHAWK::FBBackendBIZHAWK(OSystem& osystem)
+  : myOSystem{osystem}
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+FBBackendBIZHAWK::~FBBackendBIZHAWK()
+{
+
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::queryHardware(vector<Common::Size>& fullscreenRes,
+                                  vector<Common::Size>& windowedRes,
+                                  VariantList& renderers)
+{
+
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBBackendBIZHAWK::isCurrentWindowPositioned() const
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Common::Point FBBackendBIZHAWK::getCurrentWindowPos() const
+{
+  Common::Point pos;
+
+
+  return pos;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Int32 FBBackendBIZHAWK::getCurrentDisplayIndex() const
+{
+
+
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBBackendBIZHAWK::setVideoMode(const VideoModeHandler::Mode& mode,
+                                 int winIdx, const Common::Point& winPos)
+{
+
+  return true;
+}
+
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBBackendBIZHAWK::createRenderer(const VideoModeHandler::Mode& mode)
+{
+
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::setTitle(string_view title)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+string FBBackendBIZHAWK::about() const
+{
+  return "";
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::showCursor(bool show)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::grabMouse(bool grab)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBBackendBIZHAWK::fullScreen() const
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+int FBBackendBIZHAWK::refreshRate() const
+{
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::renderToScreen()
+{
+
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::setWindowIcon()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+unique_ptr<FBSurface> FBBackendBIZHAWK::createSurface(
+  uInt32 w,
+  uInt32 h,
+  ScalingInterpolation inter,
+  const uInt32* data
+) const
+{
+  return make_unique<FBSurfaceBIZHAWK>
+      (const_cast<FBBackendBIZHAWK&>(*this), w, h, inter, data);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::readPixels(uInt8* buffer, size_t pitch,
+                               const Common::Rect& rect) const
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::clear()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::detectFeatures()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBBackendBIZHAWK::detectRenderTargetSupport()
+{
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBBackendBIZHAWK::determineDimensions()
+{
+}

waterbox/stella/port/FBBackendBizhawk.hxx

@@ -0,0 +1,273 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#ifndef FB_BACKEND_BIZHAWK_HXX
+#define FB_BACKEND_BIZHAWK_HXX
+
+class OSystem;
+class FBSurfaceBIZHAWK;
+
+#include "bspf.hxx"
+#include "FBBackend.hxx"
+
+/**
+  This class implements a standard BIZHAWK 2D, hardware accelerated framebuffer
+  backend.  Behind the scenes, it may be using Direct3D, OpenGL(ES), etc.
+
+  @author  Stephen Anthony
+*/
+class FBBackendBIZHAWK : public FBBackend
+{
+  public:
+    /**
+      Creates a new BIZHAWK framebuffer
+    */
+    explicit FBBackendBIZHAWK(OSystem& osystem);
+    ~FBBackendBIZHAWK() override;
+
+  public:
+
+    /**
+      Is the renderer initialized?
+     */
+    bool isInitialized() const { return true; }
+
+    /**
+      Does the renderer support render targets?
+     */
+    bool hasRenderTargetSupport() const { return true;; }
+
+    /**
+      Transform from window to renderer coordinates, x direction
+     */
+    int scaleX(int x) const override { return 1; }
+
+    /**
+      Transform from window to renderer coordinates, y direction
+     */
+    int scaleY(int y) const override { return 1; }
+
+  protected:
+    /**
+      Updates window title.
+
+      @param title  The title of the application / window
+    */
+    void setTitle(string_view title) override;
+
+    /**
+      Shows or hides the cursor based on the given boolean value.
+    */
+    void showCursor(bool show) override;
+
+    /**
+      Answers if the display is currently in fullscreen mode.
+    */
+    bool fullScreen() const override;
+
+    /**
+      This method is called to retrieve the R/G/B data from the given pixel.
+
+      @param pixel  The pixel containing R/G/B data
+      @param r      The red component of the color
+      @param g      The green component of the color
+      @param b      The blue component of the color
+    */
+    FORCE_INLINE void getRGB(uInt32 pixel, uInt8* r, uInt8* g, uInt8* b) const override
+      { }
+
+    /**
+      This method is called to retrieve the R/G/B/A data from the given pixel.
+
+      @param pixel  The pixel containing R/G/B data
+      @param r      The red component of the color
+      @param g      The green component of the color
+      @param b      The blue component of the color
+      @param a      The alpha component of the color.
+    */
+    FORCE_INLINE void getRGBA(uInt32 pixel, uInt8* r, uInt8* g, uInt8* b, uInt8* a) const override
+      { }
+
+    /**
+      This method is called to map a given R/G/B triple to the screen palette.
+
+      @param r  The red component of the color.
+      @param g  The green component of the color.
+      @param b  The blue component of the color.
+    */
+    inline uInt32 mapRGB(uInt8 r, uInt8 g, uInt8 b) const override
+      { return 0; }
+
+    /**
+      This method is called to map a given R/G/B/A triple to the screen palette.
+
+      @param r  The red component of the color.
+      @param g  The green component of the color.
+      @param b  The blue component of the color.
+      @param a  The alpha component of the color.
+    */
+    inline uInt32 mapRGBA(uInt8 r, uInt8 g, uInt8 b, uInt8 a) const override
+      { return 0; }
+
+    /**
+      This method is called to get a copy of the specified ARGB data from the
+      viewable FrameBuffer area.  Note that this isn't the same as any
+      internal surfaces that may be in use; it should return the actual data
+      as it is currently seen onscreen.
+
+      @param buffer  A copy of the pixel data in ARGB8888 format
+      @param pitch   The pitch (in bytes) for the pixel data
+      @param rect    The bounding rectangle for the buffer
+    */
+    void readPixels(uInt8* buffer, size_t pitch,
+                    const Common::Rect& rect) const override;
+
+    /**
+      This method is called to query if the current window is not centered
+      or fullscreen.
+
+      @return  True, if the current window is positioned
+    */
+    bool isCurrentWindowPositioned() const override;
+
+    /**
+      This method is called to query the video hardware for position of
+      the current window
+
+      @return  The position of the currently displayed window
+    */
+    Common::Point getCurrentWindowPos() const override;
+
+    /**
+      This method is called to query the video hardware for the index
+      of the display the current window is displayed on
+
+      @return  the current display index or a negative value if no
+               window is displayed
+    */
+    Int32 getCurrentDisplayIndex() const override;
+
+    /**
+      Clear the frame buffer.
+    */
+    void clear() override;
+
+    /**
+      This method is called to query and initialize the video hardware
+      for desktop and fullscreen resolution information.  Since several
+      monitors may be attached, we need the resolution for all of them.
+
+      @param fullscreenRes  Maximum resolution supported in fullscreen mode
+      @param windowedRes    Maximum resolution supported in windowed mode
+      @param renderers      List of renderer names (internal name -> end-user name)
+    */
+    void queryHardware(vector<Common::Size>& fullscreenRes,
+                       vector<Common::Size>& windowedRes,
+                       VariantList& renderers) override;
+
+    /**
+      This method is called to change to the given video mode.
+
+      @param mode   The video mode to use
+      @param winIdx The display/monitor that the window last opened on
+      @param winPos The position that the window last opened at
+
+      @return  False on any errors, else true
+    */
+    bool setVideoMode(const VideoModeHandler::Mode& mode,
+                      int winIdx, const Common::Point& winPos) override;
+
+    /**
+      This method is called to create a surface with the given attributes.
+
+      @param w      The requested width of the new surface.
+      @param h      The requested height of the new surface.
+      @param inter  Interpolation mode
+      @param data   If non-null, use the given data values as a static surface
+    */
+    unique_ptr<FBSurface>
+        createSurface(
+          uInt32 w,
+          uInt32 h,
+          ScalingInterpolation inter,
+          const uInt32* data
+        ) const override;
+
+    /**
+      Grabs or ungrabs the mouse based on the given boolean value.
+    */
+    void grabMouse(bool grab) override;
+
+    /**
+      This method is called to provide information about the backend.
+    */
+    string about() const override;
+
+    /**
+      Create a new renderer if required.
+
+      @return  False on any errors, else true
+    */
+    bool createRenderer(const VideoModeHandler::Mode& mode);
+
+    /**
+      This method must be called after all drawing is done, and indicates
+      that the buffers should be pushed to the physical screen.
+    */
+    void renderToScreen() override;
+
+    /**
+      Retrieve the current display's refresh rate, or 0 if no window.
+    */
+    int refreshRate() const override;
+
+    /**
+      After the renderer has been created, detect the features it supports.
+     */
+    void detectFeatures();
+
+    /**
+      Detect render target support.
+     */
+    bool detectRenderTargetSupport();
+
+    /**
+      Determine window and renderer dimensions.
+     */
+    void determineDimensions();
+
+    /**
+      Set the icon for the main SDL window.
+    */
+    void setWindowIcon();
+
+  private:
+    OSystem& myOSystem;
+
+    // Center setting of current window
+    bool myCenter{false};
+
+  private:
+    // Following constructors and assignment operators not supported
+    FBBackendBIZHAWK() = delete;
+    FBBackendBIZHAWK(const FBBackendBIZHAWK&) = delete;
+    FBBackendBIZHAWK(FBBackendBIZHAWK&&) = delete;
+    FBBackendBIZHAWK& operator=(const FBBackendBIZHAWK&) = delete;
+    FBBackendBIZHAWK& operator=(FBBackendBIZHAWK&&) = delete;
+};
+
+#endif

waterbox/stella/port/FBSurfaceBizhawk.cxx

@@ -0,0 +1,152 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#include "FBSurfaceBizhawk.hxx"
+
+#include "Logger.hxx"
+#include "ThreadDebugging.hxx"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+FBSurfaceBIZHAWK::FBSurfaceBIZHAWK(FBBackendBIZHAWK& backend,
+                             uInt32 width, uInt32 height,
+                             ScalingInterpolation inter,
+                             const uInt32* staticData)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+FBSurfaceBIZHAWK::~FBSurfaceBIZHAWK()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::fillRect(uInt32 x, uInt32 y, uInt32 w, uInt32 h, ColorId color)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt32 FBSurfaceBIZHAWK::width() const
+{
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt32 FBSurfaceBIZHAWK::height() const
+{
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+const Common::Rect& FBSurfaceBIZHAWK::srcRect() const
+{
+  Common::Rect a;
+  return a;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+const Common::Rect& FBSurfaceBIZHAWK::dstRect() const
+{
+  Common::Rect a;
+  return a;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setSrcPos(uInt32 x, uInt32 y)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setSrcSize(uInt32 w, uInt32 h)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setSrcRect(const Common::Rect& r)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setDstPos(uInt32 x, uInt32 y)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setDstSize(uInt32 w, uInt32 h)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setDstRect(const Common::Rect& r)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setVisible(bool visible)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::translateCoords(Int32& x, Int32& y) const
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool FBSurfaceBIZHAWK::render()
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::invalidate()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::invalidateRect(uInt32 x, uInt32 y, uInt32 w, uInt32 h)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::reload()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::resize(uInt32 width, uInt32 height)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::createSurface(uInt32 width, uInt32 height,
+                                  const uInt32* data)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::reinitializeBlitter(bool force)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::applyAttributes()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void FBSurfaceBIZHAWK::setScalingInterpolation(ScalingInterpolation interpolation)
+{
+}

waterbox/stella/port/FBSurfaceBizhawk.hxx

@@ -0,0 +1,89 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#ifndef FBSURFACE_BIZHAWK_HXX
+#define FBSURFACE_BIZHAWK_HXX
+
+#include "bspf.hxx"
+#include "FBSurface.hxx"
+#include "FBBackendBizhawk.hxx"
+
+/**
+  An FBSurface suitable for the BIZHAWK Render2D API, making use of hardware
+  acceleration behind the scenes.
+
+  @author  Stephen Anthony
+*/
+class FBSurfaceBIZHAWK : public FBSurface
+{
+  public:
+    FBSurfaceBIZHAWK(FBBackendBIZHAWK& backend, uInt32 width, uInt32 height,
+                  ScalingInterpolation inter, const uInt32* staticData);
+    ~FBSurfaceBIZHAWK() override;
+
+    // Most of the surface drawing primitives are implemented in FBSurface;
+    // the ones implemented here use SDL-specific code for extra performance
+    //
+    void fillRect(uInt32 x, uInt32 y, uInt32 w, uInt32 h, ColorId color) override;
+
+    uInt32 width() const override;
+    uInt32 height() const override;
+
+    const Common::Rect& srcRect() const override;
+    const Common::Rect& dstRect() const override;
+    void setSrcPos(uInt32 x, uInt32 y) override;
+    void setSrcSize(uInt32 w, uInt32 h) override;
+    void setSrcRect(const Common::Rect& r) override;
+    void setDstPos(uInt32 x, uInt32 y) override;
+    void setDstSize(uInt32 w, uInt32 h) override;
+    void setDstRect(const Common::Rect& r) override;
+
+    void setVisible(bool visible) override;
+
+    void translateCoords(Int32& x, Int32& y) const override;
+    bool render() override;
+    void invalidate() override;
+    void invalidateRect(uInt32 x, uInt32 y, uInt32 w, uInt32 h) override;
+
+    void reload() override;
+    void resize(uInt32 width, uInt32 height) override;
+
+    void setScalingInterpolation(ScalingInterpolation) override;
+
+  protected:
+    void applyAttributes() override;
+
+    void createSurface(uInt32 width, uInt32 height, const uInt32* data);
+
+    void reinitializeBlitter(bool force = false);
+
+    // Following constructors and assignment operators not supported
+    FBSurfaceBIZHAWK() = delete;
+    FBSurfaceBIZHAWK(const FBSurfaceBIZHAWK&) = delete;
+    FBSurfaceBIZHAWK(FBSurfaceBIZHAWK&&) = delete;
+    FBSurfaceBIZHAWK& operator=(const FBSurfaceBIZHAWK&) = delete;
+    FBSurfaceBIZHAWK& operator=(FBSurfaceBIZHAWK&&) = delete;
+
+  private:
+
+    bool myIsVisible{true};
+    bool myIsStatic{false};
+
+    Common::Rect mySrcGUIR, myDstGUIR;
+};
+
+#endif

waterbox/stella/port/OSystemBizhawk.cxx

@@ -0,0 +1,31 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#include <cstdlib>
+
+#include "FSNode.hxx"
+#include "OSystemBizhawk.hxx"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void OSystemBIZHAWK::getBaseDirectories(string& basedir, string& homedir,
+                                     bool useappdir, string_view usedir)
+{
+}
+
+void OSystemBIZHAWK::initPersistence(FSNode& basedir) {}
+
+string OSystemBIZHAWK::describePresistence() { return ""; };

waterbox/stella/port/OSystemBizhawk.hxx

@@ -0,0 +1,62 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#pragma once
+
+#include "OSystemStandalone.hxx"
+
+/**
+  This class defines an OSystem object for UNIX-like OS's (Linux).
+  It is responsible for completely implementing getBaseDirectories(),
+  to set the base directory and various other save/load locations.
+
+  @author  Stephen Anthony
+*/
+class OSystemBIZHAWK : public OSystemStandalone
+{
+  public:
+    OSystemBIZHAWK() = default;
+    ~OSystemBIZHAWK() override = default;
+
+    /**
+      Determine the base directory and home directory from the derived
+      class.  It can also use hints, as described below.
+
+      @param basedir  The base directory for all configuration files
+      @param homedir  The default directory to store various other files
+      @param useappdir  A hint that the base dir should be set to the
+                        app directory; not all ports can do this, so
+                        they are free to ignore it
+      @param usedir     A hint that the base dir should be set to this
+                        parameter; not all ports can do this, so
+                        they are free to ignore it
+    */
+    void getBaseDirectories(string& basedir, string& homedir,
+                            bool useappdir, string_view usedir) override;
+
+    void initPersistence(FSNode& basedir) override;
+
+    string describePresistence() override;
+
+  private:
+    // Following constructors and assignment operators not supported
+    OSystemBIZHAWK(const OSystemBIZHAWK&) = delete;
+    OSystemBIZHAWK(OSystemBIZHAWK&&) = delete;
+    OSystemBIZHAWK& operator=(const OSystemBIZHAWK&) = delete;
+    OSystemBIZHAWK& operator=(OSystemBIZHAWK&&) = delete;
+};
+

waterbox/stella/port/SoundBizhawk.cxx

@@ -0,0 +1,131 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#ifdef SOUND_SUPPORT
+
+#include <cmath>
+#include "Logger.hxx"
+#include "FrameBuffer.hxx"
+#include "OSystem.hxx"
+#include "Console.hxx"
+#include "AudioQueue.hxx"
+#include "EmulationTiming.hxx"
+#include "AudioSettings.hxx"
+#include "audio/SimpleResampler.hxx"
+#include "audio/LanczosResampler.hxx"
+#include "ThreadDebugging.hxx"
+#include "SoundBizhawk.hxx"
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+SoundBizhawk::SoundBizhawk(OSystem& osystem, AudioSettings& audioSettings)
+  : Sound{osystem},
+    myAudioSettings{audioSettings}
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+SoundBizhawk::~SoundBizhawk()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::queryHardware(VariantList& devices)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool SoundBizhawk::openDevice()
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::setEnabled(bool enable)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::open(shared_ptr<AudioQueue> audioQueue,
+                     EmulationTiming* emulationTiming)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::mute(bool enable)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::toggleMute()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool SoundBizhawk::pause(bool enable)
+{
+  return false;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::setVolume(uInt32 volume)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::adjustVolume(int direction)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+string SoundBizhawk::about() const
+{
+  ostringstream buf;
+  return buf.str();
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::initResampler()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::callback(void* object, uInt8* stream, int len)
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool SoundBizhawk::playWav(const string& fileName, const uInt32 position,
+                        const uInt32 length)
+{
+  return true;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void SoundBizhawk::stopWav()
+{
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+uInt32 SoundBizhawk::wavSize() const
+{
+  return 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+
+#endif  // SOUND_SUPPORT

waterbox/stella/port/SoundBizhawk.hxx

@@ -0,0 +1,174 @@
+//============================================================================
+//
+//   SSSS    tt          lll  lll
+//  SS  SS   tt           ll   ll
+//  SS     tttttt  eeee   ll   ll   aaaa
+//   SSSS    tt   ee  ee  ll   ll      aa
+//      SS   tt   eeeeee  ll   ll   aaaaa  --  "An Atari 2600 VCS Emulator"
+//  SS  SS   tt   ee      ll   ll  aa  aa
+//   SSSS     ttt  eeeee llll llll  aaaaa
+//
+// Copyright (c) 1995-2024 by Bradford W. Mott, Stephen Anthony
+// and the Stella Team
+//
+// See the file "License.txt" for information on usage and redistribution of
+// this file, and for a DISCLAIMER OF ALL WARRANTIES.
+//============================================================================
+
+#ifdef SOUND_SUPPORT
+
+#ifndef SOUND_SDL2_HXX
+#define SOUND_SDL2_HXX
+
+class OSystem;
+class AudioQueue;
+class EmulationTiming;
+class AudioSettings;
+class Resampler;
+
+#include "bspf.hxx"
+#include "Sound.hxx"
+
+/**
+  This class implements the sound API for SDL.
+
+  @author Stephen Anthony and Christian Speckner (DirtyHairy)
+*/
+class SoundBizhawk : public Sound
+{
+  public:
+    /**
+      Create a new sound object.  The init method must be invoked before
+      using the object.
+    */
+    SoundBizhawk(OSystem& osystem, AudioSettings& audioSettings);
+
+    /**
+      Destructor
+    */
+    ~SoundBizhawk() override;
+
+  public:
+    /**
+      Enables/disables the sound subsystem.
+
+      @param enable  Either true or false, to enable or disable the sound system
+    */
+    void setEnabled(bool enable) override;
+
+    /**
+      Initializes the sound device.  This must be called before any
+      calls are made to derived methods.
+    */
+    void open(shared_ptr<AudioQueue> audioQueue,
+              EmulationTiming* emulationTiming) override;
+
+    /**
+      Sets the sound mute state; sound processing continues.  When enabled,
+      sound volume is 0; when disabled, sound volume returns to previously
+      set level.
+
+      @param enable  Mutes sound if true, unmute if false
+    */
+    void mute(bool enable) override;
+
+    /**
+      Toggles the sound mute state; sound processing continues.
+      Switches between mute(true) and mute(false).
+    */
+    void toggleMute() override;
+
+    /**
+      Set the pause state of the sound object.  While paused, sound is
+      neither played nor processed (ie, the sound subsystem is temporarily
+      disabled).
+
+      @param enable  Pause sound if true, unpause if false
+
+      @return  The previous (old) pause state
+    */
+    bool pause(bool enable) override;
+
+    /**
+      Sets the volume of the sound device to the specified level.  The
+      volume is given as a range from 0 to 100 (0 indicates mute).  Values
+      outside this range indicate that the volume shouldn't be changed at all.
+
+      @param volume  The new volume level for the sound device
+    */
+    void setVolume(uInt32 volume) override;
+
+    /**
+      Adjusts the volume of the sound device based on the given direction.
+
+      @param direction  +1 indicates increase, -1 indicates decrease.
+      */
+    void adjustVolume(int direction = 1) override;
+
+    /**
+      This method is called to provide information about the sound device.
+    */
+    string about() const override;
+
+    /**
+      Play a WAV file.
+
+      @param fileName  The name of the WAV file
+      @param position  The position to start playing
+      @param length    The played length
+
+      @return  True if the WAV file can be played, else false
+    */
+    bool playWav(const string& fileName, const uInt32 position = 0,
+                 const uInt32 length = 0) override;
+
+    /**
+      Stop any currently playing WAV file.
+    */
+    void stopWav() override;
+
+    /**
+      Get the size of the WAV file which remains to be played.
+
+      @return  The remaining number of bytes
+    */
+    uInt32 wavSize() const override;
+
+  private:
+    /**
+      This method is called to query the audio devices.
+
+      @param devices  List of device names
+    */
+    void queryHardware(VariantList& devices) override;
+
+    /**
+      The actual sound device is opened only when absolutely necessary.
+      Typically this will only happen once per program run, but it can also
+      happen dynamically when changing sample rate and/or fragment size.
+    */
+    bool openDevice();
+
+    void initResampler();
+
+  private:
+    AudioSettings& myAudioSettings;
+
+    // Audio specification structure
+    static float myVolumeFactor;  // Current volume level (0 - 100)
+
+  private:
+    // Callback functions invoked by the SDL Audio library when it needs data
+    static void callback(void* object, uInt8* stream, int len);
+
+    // Following constructors and assignment operators not supported
+    SoundBizhawk() = delete;
+    SoundBizhawk(const SoundBizhawk&) = delete;
+    SoundBizhawk(SoundBizhawk&&) = delete;
+    SoundBizhawk& operator=(const SoundBizhawk&) = delete;
+    SoundBizhawk& operator=(SoundBizhawk&&) = delete;
+};
+
+#endif
+
+#endif  // SOUND_SUPPORT