Rendering - Sovled inconsistencies between software and Vulkan rendering

LED sampling - Improved LED sampling on <100% scale

src/Artemis.Core/RGB.NET/SKTexture.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers;
 using System.Runtime.InteropServices;
 using Artemis.Core.SkiaSharp;
 using RGB.NET.Core;
@@ -12,25 +13,54 @@ namespace Artemis.Core
     /// </summary>
     public sealed class SKTexture : PixelTexture<byte>, IDisposable
     {
+        private readonly bool _isScaledDown;
         private readonly SKPixmap _pixelData;
         private readonly IntPtr _pixelDataPtr;
 
         #region Constructors
 
-        internal SKTexture(IManagedGraphicsContext? graphicsContext, int width, int height, float scale) : base(width, height, 4, new AverageByteSampler())
+        internal SKTexture(IManagedGraphicsContext? graphicsContext, int width, int height, float scale) : base(width, height, DATA_PER_PIXEL, new AverageByteSampler())
         {
             ImageInfo = new SKImageInfo(width, height);
-            Surface = graphicsContext == null 
-                ? SKSurface.Create(ImageInfo) 
+            Surface = graphicsContext == null
+                ? SKSurface.Create(ImageInfo)
                 : SKSurface.Create(graphicsContext.GraphicsContext, true, ImageInfo);
             RenderScale = scale;
-
+            _isScaledDown = Math.Abs(scale - 1) > 0.001;
             _pixelDataPtr = Marshal.AllocHGlobal(ImageInfo.BytesSize);
             _pixelData = new SKPixmap(ImageInfo, _pixelDataPtr, ImageInfo.RowBytes);
         }
 
         #endregion
 
+        private void ReleaseUnmanagedResources()
+        {
+            Marshal.FreeHGlobal(_pixelDataPtr);
+        }
+
+        /// <inheritdoc />
+        ~SKTexture()
+        {
+            ReleaseUnmanagedResources();
+        }
+
+        /// <inheritdoc />
+        public void Dispose()
+        {
+            Surface.Dispose();
+            _pixelData.Dispose();
+
+            ReleaseUnmanagedResources();
+            GC.SuppressFinalize(this);
+        }
+
+        #region Constants
+
+        private const int STACK_ALLOC_LIMIT = 1024;
+        private const int DATA_PER_PIXEL = 4;
+
+        #endregion
+
         #region Methods
 
         /// <summary>
@@ -53,6 +83,61 @@ namespace Artemis.Core
             return new(pixel[2], pixel[1], pixel[0]);
         }
 
+        /// <inheritdoc />
+        public override Color this[in Rectangle rectangle]
+        {
+            get
+            {
+                if (Data.Length == 0) return Color.Transparent;
+
+                SKRectI skRectI = CreatedFlooredRectI(
+                    Size.Width * rectangle.Location.X.Clamp(0, 1),
+                    Size.Height * rectangle.Location.Y.Clamp(0, 1),
+                    Size.Width * rectangle.Size.Width.Clamp(0, 1),
+                    Size.Height * rectangle.Size.Height.Clamp(0, 1)
+                );
+
+                if (skRectI.Width == 0 || skRectI.Height == 0) return Color.Transparent;
+                if (skRectI.Width == 1 && skRectI.Height == 1) return GetColor(GetPixelData(skRectI.Left, skRectI.Top));
+
+                int bufferSize = skRectI.Width * skRectI.Height * DATA_PER_PIXEL;
+                if (bufferSize <= STACK_ALLOC_LIMIT)
+                {
+                    Span<byte> buffer = stackalloc byte[bufferSize];
+                    GetRegionData(skRectI.Left, skRectI.Top, skRectI.Width, skRectI.Height, buffer);
+
+                    Span<byte> pixelData = stackalloc byte[DATA_PER_PIXEL];
+                    Sampler.SampleColor(new SamplerInfo<byte>(skRectI.Width, skRectI.Height, buffer), pixelData);
+
+                    return GetColor(pixelData);
+                }
+                else
+                {
+                    byte[] rent = ArrayPool<byte>.Shared.Rent(bufferSize);
+
+                    Span<byte> buffer = new Span<byte>(rent).Slice(0, bufferSize);
+                    GetRegionData(skRectI.Left, skRectI.Top, skRectI.Width, skRectI.Height, buffer);
+
+                    Span<byte> pixelData = stackalloc byte[DATA_PER_PIXEL];
+                    Sampler.SampleColor(new SamplerInfo<byte>(skRectI.Width, skRectI.Height, buffer), pixelData);
+
+                    ArrayPool<byte>.Shared.Return(rent);
+
+                    return GetColor(pixelData);
+                }
+            }
+        }
+
+        private static SKRectI CreatedFlooredRectI(float x, float y, float width, float height)
+        {
+            return new(
+                width <= 0.0 ? checked((int) Math.Floor(x)) : checked((int) Math.Ceiling(x)),
+                height <= 0.0 ? checked((int) Math.Floor(y)) : checked((int) Math.Ceiling(y)),
+                width >= 0.0 ? checked((int) Math.Floor(x + width)) : checked((int) Math.Ceiling(x + width)),
+                height >= 0.0 ? checked((int) Math.Floor(y + height)) : checked((int) Math.Ceiling(y + height))
+            );
+        }
+
         #endregion
 
         #region Properties & Fields
@@ -84,30 +169,5 @@ namespace Artemis.Core
         public bool IsInvalid { get; private set; }
 
         #endregion
-
-        #region IDisposable
-
-        private void ReleaseUnmanagedResources()
-        {
-            Marshal.FreeHGlobal(_pixelDataPtr);
-        }
-
-        /// <inheritdoc />
-        public void Dispose()
-        {
-            Surface.Dispose();
-            _pixelData.Dispose();
-            
-            ReleaseUnmanagedResources();
-            GC.SuppressFinalize(this);
-        }
-
-        /// <inheritdoc />
-        ~SKTexture()
-        {
-            ReleaseUnmanagedResources();
-        }
-
-        #endregion
     }
 }