Add in screen control filter for Citra port

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

@@ -16,6 +16,7 @@ using BizHawk.Client.Common.Filters;
 using BizHawk.Common.CollectionExtensions;
 using BizHawk.Common.PathExtensions;
 using BizHawk.Emulation.Common;
+using BizHawk.Emulation.Cores.Consoles.Nintendo._3DS;
 using BizHawk.Emulation.Cores.Consoles.Nintendo.NDS;
 using BizHawk.Emulation.Cores.Sony.PSX;
 
@@ -436,18 +437,10 @@ namespace BizHawk.Client.Common
 			if (_currentFilterProgram == null) return p;
 
 			// otherwise, have the filter program untransform it
-			Vector2 v = new Vector2(p.X, p.Y);
+			var v = new Vector2(p.X, p.Y);
 			v = _currentFilterProgram.UntransformPoint("default", v);
 
-			// Poop
+			return new((int)v.X, (int)v.Y);
-			//if (Global.Emulator is MelonDS ds && ds.TouchScreenStart.HasValue)
-			//{
-			//	Point touchLocation = ds.TouchScreenStart.Value;
-			//	v.Y = (int)((double)ds.BufferHeight / MelonDS.NativeHeight * (v.Y - touchLocation.Y));
-			//	v.X = (int)((double)ds.BufferWidth / MelonDS.NativeWidth * (v.X - touchLocation.X));
-			//}
-
-			return new Point((int)v.X, (int)v.Y);
 		}
 
 		/// <summary>
@@ -462,9 +455,9 @@ namespace BizHawk.Client.Common
 			}
 
 			// otherwise, have the filter program untransform it
-			Vector2 v = new Vector2(p.X, p.Y);
+			var v = new Vector2(p.X, p.Y);
 			v = _currentFilterProgram.TransformPoint("default", v);
-			return new Point((int)v.X, (int)v.Y);
+			return new((int)v.X, (int)v.Y);
 		}
 
 		public virtual Size GetPanelNativeSize() => throw new NotImplementedException();
@@ -474,9 +467,6 @@ namespace BizHawk.Client.Common
 		/// <summary>
 		/// This will receive an emulated output frame from an IVideoProvider and run it through the complete frame processing pipeline
 		/// Then it will stuff it into the bound PresentationPanel.
-		/// ---
-		/// If the int[] is size=1, then it contains an openGL texture ID (and the size should be as specified from videoProvider)
-		/// Don't worry about the case where the frontend isnt using opengl; DisplayManager deals with it
 		/// </summary>
 		public void UpdateSource(IVideoProvider videoProvider)
 		{
@@ -494,14 +484,12 @@ namespace BizHawk.Client.Common
 
 		private BaseFilter CreateCoreScreenControl()
 		{
-			if (GlobalEmulator is NDS nds)
+			return GlobalEmulator switch
 			{
-				//TODO: need to pipe layout settings into here now
+				NDS nds => new ScreenControlNDS(nds),
-				var filter = new ScreenControlNDS(nds);
+				Citra citra => new ScreenControl3DS(citra),
-				return filter;
+				_ => null
-			}
+			};
-
-			return null;
 		}
 
 		/// <summary>

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

@@ -82,7 +82,7 @@ namespace BizHawk.Client.Common.FilterManager
 		/// </summary>
 		public Vector2 UntransformPoint(string channel, Vector2 point)
 		{
-			for (int i = Filters.Count - 1; i >= 0; i--)
+			for (var i = Filters.Count - 1; i >= 0; i--)
 			{
 				var filter = Filters[i];
 				point = filter.UntransformPoint(channel, point);

src/BizHawk.Client.Common/DisplayManager/Filters/Gui.cs

@@ -1,9 +1,11 @@
 using System;
 using System.Drawing;
-using BizHawk.Client.Common.FilterManager;
-using BizHawk.Emulation.Cores.Consoles.Nintendo.NDS;
 
 using BizHawk.Bizware.BizwareGL;
+using BizHawk.Client.Common.FilterManager;
+using BizHawk.Emulation.Common;
+using BizHawk.Emulation.Cores.Consoles.Nintendo._3DS;
+using BizHawk.Emulation.Cores.Consoles.Nintendo.NDS;
 
 namespace BizHawk.Client.Common.Filters
 {
@@ -416,6 +418,76 @@ namespace BizHawk.Client.Common.Filters
 		}
 	}
 
+	/// <summary>
+	/// special screen control features for 3DS
+	/// in practice, this is only for correcting mouse input
+	/// as the core internally handles screen drawing madness anyways
+	/// </summary>
+	public class ScreenControl3DS : BaseFilter
+	{
+		private readonly Citra _citra;
+
+		public ScreenControl3DS(Citra citra)
+		{
+			_citra = citra;
+		}
+
+		public override Vector2 UntransformPoint(string channel, Vector2 point)
+		{
+			if (_citra.TouchScreenEnabled)
+			{
+				var rect = _citra.TouchScreenRectangle;
+				var rotated = _citra.TouchScreenRotated;
+				var bufferWidth = (float)_citra.AsVideoProvider().BufferWidth;
+				var bufferHeight = (float)_citra.AsVideoProvider().BufferHeight;
+
+				// reset the point's origin to the top left of the screen
+				point.X -= rect.X;
+				point.Y -= rect.Y;
+				if (rotated)
+				{
+					// scale our point now
+					// X is for height here and Y is for width, due to rotation
+					point.X *= bufferHeight / rect.Width;
+					point.Y *= bufferWidth / rect.Height;
+					// adjust point
+					point = new(bufferWidth - point.Y, point.X);
+				}
+				else
+				{
+					// scale our point now
+					point.X *= bufferWidth / rect.Width;
+					point.Y *= bufferHeight / rect.Height;
+				}
+			}
+
+			return point;
+		}
+
+		public override Vector2 TransformPoint(string channel, Vector2 point)
+		{
+			if (_citra.TouchScreenEnabled)
+			{
+				var rect = _citra.TouchScreenRectangle;
+				var rotated = _citra.TouchScreenRotated;
+
+				if (rotated)
+				{
+					// adjust point
+					point = new(point.Y, rect.Height - point.X);
+				}
+
+				// reset the point's origin to the top left of the screen
+				point.X += rect.X;
+				point.Y += rect.Y;
+
+				// TODO: this doesn't handle "large screen" mode correctly
+			}
+
+			return point;
+		}
+	}
+
 	public class FinalPresentation : BaseFilter
 	{
 		public enum eFilterOption

src/BizHawk.Emulation.Cores/Consoles/Nintendo/3DS/Citra.IEmulator.cs

@@ -33,8 +33,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo._3DS
 
 			_core.Citra_RunFrame(_context);
 
-			_core.Citra_GetVideoDimensions(_context, out _citraVideoProvider.Width, out _citraVideoProvider.Height);
+			OnVideoRefresh();
-			_citraVideoProvider.VideoDirty = true;
 
 			if (renderSound)
 			{
@@ -50,6 +49,17 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo._3DS
 			return true;
 		}
 
+		private void OnVideoRefresh()
+		{
+			_core.Citra_GetVideoDimensions(_context, out _citraVideoProvider.Width, out _citraVideoProvider.Height);
+			_citraVideoProvider.VideoDirty = true;
+
+			_core.Citra_GetTouchScreenLayout(_context, out var x, out var y, out var width, out var height, out var rotated, out var enabled);
+			TouchScreenRectangle = new(x, y, width, height);
+			TouchScreenRotated = rotated;
+			TouchScreenEnabled = enabled;
+		}
+
 		public void ResetCounters()
 		{
 			Frame = 0;

src/BizHawk.Emulation.Cores/Consoles/Nintendo/3DS/Citra.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Drawing;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Text;
@@ -34,6 +35,10 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo._3DS
 		private readonly IntPtr _context;
 		private readonly CitraVideoProvider _citraVideoProvider;
 
+		public Rectangle TouchScreenRectangle { get; private set; }
+		public bool TouchScreenRotated { get; private set; }
+		public bool TouchScreenEnabled { get; private set; }
+
 		[CoreConstructor(VSystemID.Raw._3DS)]
 		public Citra(CoreLoadParameters<CitraSettings, CitraSyncSettings> lp)
 		{
@@ -131,6 +136,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo._3DS
 			}
 
 			InitMemoryDomains();
+			OnVideoRefresh();
 		}
 
 		private IntPtr RequestGLContextCallback()

src/BizHawk.Emulation.Cores/Consoles/Nintendo/3DS/LibCitra.cs

@@ -160,5 +160,8 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo._3DS
 
 		[BizImport(cc)]
 		public abstract void Citra_GetMemoryRegion(IntPtr context, MemoryRegion region, out IntPtr ptr, out int size);
+
+		[BizImport(cc)]
+		public abstract void Citra_GetTouchScreenLayout(IntPtr context, out int x, out int y, out int width, out int height, out bool rotated, out bool enabled);
 	}
 }