Extract interface from DisplaySurface

src/BizHawk.Client.Common/Api/Classes/GuiApi.cs

@@ -39,9 +39,9 @@ namespace BizHawk.Client.Common
 
 		private Color? _defaultTextBackground = Color.FromArgb(128, 0, 0, 0);
 
-		private DisplaySurface _clientSurface;
+		private IDisplaySurface _clientSurface;
 
-		private DisplaySurface _GUISurface;
+		private IDisplaySurface _GUISurface;
 
 		private (int Left, int Top, int Right, int Bottom) _padding = (0, 0, 0, 0);
 
@@ -73,7 +73,7 @@ namespace BizHawk.Client.Common
 
 		public void SetAttributes(ImageAttributes a) => _attributes = a;
 
-		private DisplaySurface GetRelevantSurface(DisplaySurfaceID? surfaceID)
+		private IDisplaySurface GetRelevantSurface(DisplaySurfaceID? surfaceID)
 		{
 			var nnID = surfaceID ?? _usingSurfaceID ?? throw new Exception();
 			void ThisIsTheLuaAutolockHack()

src/BizHawk.Client.Common/DisplayManager/DisplaySurface.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.Runtime.InteropServices;
@@ -10,7 +9,7 @@ namespace BizHawk.Client.Common
 	/// This is a wrapper for a Bitmap, basically, which can also be a int[].
 	/// It should be phased out, in favor of BitmapBuffer and Texture2d's
 	/// </summary>
-	public unsafe class DisplaySurface : IDisposable
+	public unsafe class DisplaySurface : IDisplaySurface
 	{
 		private Bitmap _bmp;
 		private BitmapData _bmpData;
@@ -28,9 +27,6 @@ namespace BizHawk.Client.Common
 			return _bmp;
 		}
 
-		/// <summary>
-		/// returns a Graphics object used to render to this surface. be sure to dispose it!
-		/// </summary>
 		public Graphics GetGraphics()
 		{
 			ToBitmap();

src/BizHawk.Client.Common/DisplayManager/IDisplayManagerForApi.cs

@@ -11,10 +11,10 @@ namespace BizHawk.Client.Common
 
 		/// <summary>locks the surface with ID <paramref name="surfaceID"/></summary>
 		/// <exception cref="InvalidOperationException">already locked, or unknown surface</exception>
-		DisplaySurface LockApiHawkSurface(DisplaySurfaceID surfaceID, bool clear = true);
+		IDisplaySurface LockApiHawkSurface(DisplaySurfaceID surfaceID, bool clear = true);
 
 		/// <summary>unlocks the given <paramref name="surface"/>, which must be a locked surface produced by <see cref="LockApiHawkSurface"/></summary>
 		/// <exception cref="InvalidOperationException">already unlocked</exception>
-		void UnlockApiHawkSurface(DisplaySurface surface);
+		void UnlockApiHawkSurface(IDisplaySurface surface);
 	}
 }

src/BizHawk.Client.Common/DisplayManager/IDisplaySurface.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Drawing;
+
+namespace BizHawk.Client.Common
+{
+	public interface IDisplaySurface : IDisposable
+	{
+		int Height { get; }
+
+		int Width { get; }
+
+		void Clear();
+
+		/// <returns>a <see cref="Graphics"/> used to render to this surface; be sure to dispose it!</returns>
+		Graphics GetGraphics();
+
+		Bitmap PeekBitmap();
+	}
+}

src/BizHawk.Client.Common/DisplayManager/TextureFrugalizer.cs

@@ -34,7 +34,7 @@ namespace BizHawk.Client.Common
 		private readonly IGL _gl;
 		private List<Texture2d> _currentTextures;
 
-		public Texture2d Get(DisplaySurface ds)
+		public Texture2d Get(IDisplaySurface ds)
 		{
 			using var bb = new BitmapBuffer(ds.PeekBitmap(), new BitmapLoadOptions());
 			return Get(bb);

src/BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs

@@ -1097,24 +1097,24 @@ namespace BizHawk.Client.EmuHawk
 		private bool? _lastVsyncSetting;
 		private GraphicsControl _lastVsyncSettingGraphicsControl;
 
-		private readonly Dictionary<DisplaySurfaceID, DisplaySurface> _apiHawkIDToSurface = new();
+		private readonly Dictionary<DisplaySurfaceID, IDisplaySurface> _apiHawkIDToSurface = new();
 
-		/// <remarks>Can't this just be a field/prop of <see cref="DisplaySurface"/>? --yoshi</remarks>
-		private readonly Dictionary<DisplaySurface, DisplaySurfaceID> _apiHawkSurfaceToID = new();
+		/// <remarks>Can't this just be a prop of <see cref="IDisplaySurface"/>? --yoshi</remarks>
+		private readonly Dictionary<IDisplaySurface, DisplaySurfaceID> _apiHawkSurfaceToID = new();
 
 		private readonly Dictionary<DisplaySurfaceID, SwappableDisplaySurfaceSet> _apiHawkSurfaceSets = new();
 
 		/// <summary>
 		/// Peeks a locked lua surface, or returns null if it isn't locked
 		/// </summary>
-		public DisplaySurface PeekApiHawkLockedSurface(DisplaySurfaceID surfaceID)
+		public IDisplaySurface PeekApiHawkLockedSurface(DisplaySurfaceID surfaceID)
 		{
 			if (_apiHawkIDToSurface.ContainsKey(surfaceID))
 				return _apiHawkIDToSurface[surfaceID];
 			return null;
 		}
 
-		public DisplaySurface LockApiHawkSurface(DisplaySurfaceID surfaceID, bool clear)
+		public IDisplaySurface LockApiHawkSurface(DisplaySurfaceID surfaceID, bool clear)
 		{
 			if (_apiHawkIDToSurface.ContainsKey(surfaceID))
 			{
@@ -1141,7 +1141,7 @@ namespace BizHawk.Client.EmuHawk
 				_ => throw new ArgumentException(message: "not a valid enum member", paramName: nameof(surfaceID))
 			};
 
-			DisplaySurface ret = sdss.AllocateSurface(width, height, clear);
+			IDisplaySurface ret = sdss.AllocateSurface(width, height, clear);
 			_apiHawkIDToSurface[surfaceID] = ret;
 			_apiHawkSurfaceToID[ret] = surfaceID;
 			return ret;
@@ -1167,19 +1167,20 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
-		/// <summary>unlocks this DisplaySurface which had better have been locked as a lua surface</summary>
+		/// <summary>unlocks this IDisplaySurface which had better have been locked as a lua surface</summary>
 		/// <exception cref="InvalidOperationException">already unlocked</exception>
-		public void UnlockApiHawkSurface(DisplaySurface surface)
+		public void UnlockApiHawkSurface(IDisplaySurface surface)
 		{
-			if (!_apiHawkSurfaceToID.ContainsKey(surface))
+			if (surface is not DisplaySurface dispSurfaceImpl) throw new ArgumentException("o noes", nameof(surface));
+			if (!_apiHawkSurfaceToID.ContainsKey(dispSurfaceImpl))
 			{
 				throw new InvalidOperationException("Surface was not locked as a lua surface");
 			}
 
-			var surfaceID = _apiHawkSurfaceToID[surface];
-			_apiHawkSurfaceToID.Remove(surface);
+			var surfaceID = _apiHawkSurfaceToID[dispSurfaceImpl];
+			_apiHawkSurfaceToID.Remove(dispSurfaceImpl);
 			_apiHawkIDToSurface.Remove(surfaceID);
-			_apiHawkSurfaceSets[surfaceID].SetPending(surface);
+			_apiHawkSurfaceSets[surfaceID].SetPending(dispSurfaceImpl);
 		}
 
 		// helper classes: