Implement changes from gdkchan/buffer-sharing-rebased

Co-authored-by: gdkchan <gab.dark.100@gmail.com>
Co-authored-by: Alula <6276139+alula@users.noreply.github.com>

src/Ryujinx.Graphics.Gpu/Window.cs

@@ -9,11 +9,18 @@ using System.Threading;
 
 namespace Ryujinx.Graphics.Gpu
 {
+    using Texture = Image.Texture;
+
+    public record TextureData(int Width, int Height, byte[] Data);
+
     /// <summary>
     /// GPU image presentation window.
     /// </summary>
     public class Window
     {
+        private const int CaptureTextureWidth = 1280;
+        private const int CaptureTextureHeight = 720;
+
         private readonly GpuContext _context;
 
         /// <summary>
@@ -85,7 +92,21 @@ namespace Ryujinx.Graphics.Gpu
             }
         }
 
+        private class PresentedTexture
+        {
+            public readonly Texture Texture;
+            public readonly ImageCrop Crop;
+
+            public PresentedTexture(Texture texture, ImageCrop crop)
+            {
+                Texture = texture;
+                Crop = crop;
+            }
+        }
+
         private readonly ConcurrentQueue<PresentationTexture> _frameQueue;
+        private PresentedTexture _lastPresentedTexture;
+        private ITexture _captureTexture;
 
         private int _framesAvailable;
 
@@ -188,6 +209,51 @@ namespace Ryujinx.Graphics.Gpu
             return true;
         }
 
+        public TextureData GetLastPresentedData()
+        {
+            PresentedTexture pt = Volatile.Read(ref _lastPresentedTexture);
+
+            if (pt != null)
+            {
+                byte[] inputData = CaptureLastFrame(pt.Texture.HostTexture, pt.Crop);
+
+                int size = SizeCalculator.GetBlockLinearTextureSize(
+                    CaptureTextureWidth,
+                    CaptureTextureHeight,
+                    1,
+                    1,
+                    1,
+                    1,
+                    1,
+                    4,
+                    16,
+                    1,
+                    1).TotalSize;
+
+                byte[] data = new byte[size];
+
+                LayoutConverter.ConvertLinearToBlockLinear(data, CaptureTextureWidth, CaptureTextureHeight, CaptureTextureWidth * 4, 4, 16, inputData);
+
+                return new TextureData(CaptureTextureWidth, CaptureTextureHeight, data);
+            }
+
+            return new TextureData(0, 0, Array.Empty<byte>());
+        }
+
+        public TextureData GetLastPresentedDataLinear()
+        {
+            PresentedTexture pt = Volatile.Read(ref _lastPresentedTexture);
+
+            if (pt != null)
+            {
+                byte[] inputData = CaptureLastFrame(pt.Texture.HostTexture, new ImageCrop());
+
+                return new TextureData(pt.Texture.Info.Width, pt.Texture.Info.Height, inputData);
+            }
+
+            return new TextureData(0, 0, Array.Empty<byte>());
+        }
+
         /// <summary>
         /// Presents a texture on the queue.
         /// If the queue is empty, then no texture is presented.
@@ -205,6 +271,10 @@ namespace Ryujinx.Graphics.Gpu
 
                 pt.Cache.Tick();
 
+                EnsureCaptureTexture();
+
+                Volatile.Write(ref _lastPresentedTexture, new PresentedTexture(texture, pt.Crop));
+
                 texture.SynchronizeMemory();
 
                 ImageCrop crop = new(
@@ -244,6 +314,96 @@ namespace Ryujinx.Graphics.Gpu
             }
         }
 
+        private void EnsureCaptureTexture()
+        {
+            if (_captureTexture == null)
+            {
+                _captureTexture = _context.Renderer.CreateTexture(new TextureCreateInfo(
+                    1280,
+                    720,
+                    1,
+                    1,
+                    1,
+                    1,
+                    1,
+                    4,
+                    Format.R8G8B8A8Unorm,
+                    DepthStencilMode.Depth,
+                    Target.Texture2D,
+                    SwizzleComponent.Red,
+                    SwizzleComponent.Green,
+                    SwizzleComponent.Blue,
+                    SwizzleComponent.Alpha));
+            }
+        }
+
+        private byte[] CaptureLastFrame(ITexture lastFrame, ImageCrop crop)
+        {
+            int cropLeft, cropRight, cropTop, cropBottom;
+
+            if (crop.Left == 0 && crop.Right == 0)
+            {
+                cropLeft = 0;
+                cropRight = lastFrame.Width;
+            }
+            else
+            {
+                cropLeft = crop.Left;
+                cropRight = crop.Right;
+            }
+
+            if (crop.Top == 0 && crop.Bottom == 0)
+            {
+                cropTop = 0;
+                cropBottom = lastFrame.Height;
+            }
+            else
+            {
+                cropTop = crop.Top;
+                cropBottom = crop.Bottom;
+            }
+
+            int x1, y1, x2, y2;
+
+            if (crop.FlipX)
+            {
+                x1 = cropRight;
+                x2 = cropLeft;
+            }
+            else
+            {
+                x1 = cropLeft;
+                x2 = cropRight;
+            }
+
+            if (crop.FlipY)
+            {
+                y1 = cropBottom;
+                y2 = cropTop;
+            }
+            else
+            {
+                y1 = cropTop;
+                y2 = cropBottom;
+            }
+
+            Extents2D srcRegion = new(x1, y1, x2, y2);
+            Extents2D dstRegion = new(0, 0, CaptureTextureWidth, CaptureTextureHeight);
+
+            byte[] outputData = null;
+
+            _context.Renderer.BackgroundContextAction(() =>
+            {
+                lastFrame.CopyTo(_captureTexture, srcRegion, dstRegion, true);
+
+                using var data = _captureTexture.GetData();
+
+                outputData = data.Get().ToArray();
+            });
+
+            return outputData;
+        }
+
         /// <summary>
         /// Indicate that a frame on the queue is ready to be acquired.
         /// </summary>