Make ResizeKernelMap non-generic.

src/ImageSharp/Processing/Processors/Transforms/Resize/ResamplerExtensions.cs

@@ -78,13 +78,13 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             // Since all image frame dimensions have to be the same we can calculate
             // the kernel maps and reuse for all frames.
             MemoryAllocator allocator = configuration.MemoryAllocator;
-            using var horizontalKernelMap = ResizeKernelMap<TResampler>.Calculate(
+            using var horizontalKernelMap = ResizeKernelMap.Calculate(
                 in sampler,
                 destinationRectangle.Width,
                 sourceRectangle.Width,
                 allocator);
 
-            using var verticalKernelMap = ResizeKernelMap<TResampler>.Calculate(
+            using var verticalKernelMap = ResizeKernelMap.Calculate(
                 in sampler,
                 destinationRectangle.Height,
                 sourceRectangle.Height,
@@ -135,17 +135,16 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
                 in operation);
         }
 
-        private static void ApplyResizeFrameTransform<TResampler, TPixel>(
+        private static void ApplyResizeFrameTransform<TPixel>(
             Configuration configuration,
             ImageFrame<TPixel> source,
             ImageFrame<TPixel> destination,
-            ResizeKernelMap<TResampler> horizontalKernelMap,
-            ResizeKernelMap<TResampler> verticalKernelMap,
+            ResizeKernelMap horizontalKernelMap,
+            ResizeKernelMap verticalKernelMap,
             Rectangle sourceRectangle,
             Rectangle destinationRectangle,
             Rectangle interest,
             bool compand)
-            where TResampler : unmanaged, IResampler
             where TPixel : struct, IPixel<TPixel>
         {
             PixelConversionModifiers conversionModifiers =
@@ -155,7 +154,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
             // To reintroduce parallel processing, we would launch multiple workers
             // for different row intervals of the image.
-            using (var worker = new ResizeWorker<TResampler, TPixel>(
+            using (var worker = new ResizeWorker<TPixel>(
                 configuration,
                 sourceArea,
                 conversionModifiers,

src/ImageSharp/Processing/Processors/Transforms/Resize/ResizeKernel.cs

@@ -8,7 +8,7 @@ using System.Runtime.CompilerServices;
 namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 {
     /// <summary>
-    /// Points to a collection of of weights allocated in <see cref="ResizeKernelMap{T}"/>.
+    /// Points to a collection of of weights allocated in <see cref="ResizeKernelMap"/>.
     /// </summary>
     internal readonly unsafe struct ResizeKernel
     {
@@ -44,7 +44,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         }
 
         /// <summary>
-        /// Gets the span representing the portion of the <see cref="ResizeKernelMap{T}"/> that this window covers.
+        /// Gets the span representing the portion of the <see cref="ResizeKernelMap"/> that this window covers.
         /// </summary>
         /// <value>The <see cref="Span{T}"/>.
         /// </value>

src/ImageSharp/Processing/Processors/Transforms/Resize/ResizeKernelMap.PeriodicKernelMap.cs

@@ -5,13 +5,12 @@ using SixLabors.ImageSharp.Memory;
 
 namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 {
-    internal partial class ResizeKernelMap<TResampler>
-        where TResampler : unmanaged, IResampler
+    internal partial class ResizeKernelMap
     {
         /// <summary>
-        /// Memory-optimized <see cref="ResizeKernelMap{TResampler}"/> where repeating rows are stored only once.
+        /// Memory-optimized <see cref="ResizeKernelMap"/> where repeating rows are stored only once.
         /// </summary>
-        private sealed class PeriodicKernelMap : ResizeKernelMap<TResampler>
+        private sealed class PeriodicKernelMap : ResizeKernelMap
         {
             private readonly int period;
 
@@ -19,7 +18,6 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
             public PeriodicKernelMap(
                 MemoryAllocator memoryAllocator,
-                TResampler sampler,
                 int sourceLength,
                 int destinationLength,
                 double ratio,
@@ -29,7 +27,6 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
                 int cornerInterval)
                 : base(
                     memoryAllocator,
-                    sampler,
                     sourceLength,
                     destinationLength,
                     (cornerInterval * 2) + period,
@@ -43,14 +40,14 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
             internal override string Info => base.Info + $"|period:{this.period}|cornerInterval:{this.cornerInterval}";
 
-            protected internal override void Initialize()
+            protected internal override void Initialize<TResampler>(in TResampler sampler)
             {
                 // Build top corner data + one period of the mosaic data:
                 int startOfFirstRepeatedMosaic = this.cornerInterval + this.period;
 
                 for (int i = 0; i < startOfFirstRepeatedMosaic; i++)
                 {
-                    this.kernels[i] = this.BuildKernel(i, i);
+                    this.kernels[i] = this.BuildKernel(in sampler, i, i);
                 }
 
                 // Copy the mosaics:
@@ -67,7 +64,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
                 int bottomStartData = this.cornerInterval + this.period;
                 for (int i = 0; i < this.cornerInterval; i++)
                 {
-                    this.kernels[bottomStartDest + i] = this.BuildKernel(bottomStartDest + i, bottomStartData + i);
+                    this.kernels[bottomStartDest + i] = this.BuildKernel(in sampler, bottomStartDest + i, bottomStartData + i);
                 }
             }
         }

src/ImageSharp/Processing/Processors/Transforms/Resize/ResizeKernelMap.cs

@@ -12,14 +12,10 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
     /// <summary>
     /// Provides resize kernel values from an optimized contiguous memory region.
     /// </summary>
-    /// <typeparam name="TResampler">The type of sampler.</typeparam>
-    internal partial class ResizeKernelMap<TResampler> : IDisposable
-        where TResampler : unmanaged, IResampler
+    internal partial class ResizeKernelMap : IDisposable
     {
         private static readonly TolerantMath TolerantMath = TolerantMath.Default;
 
-        private readonly TResampler sampler;
-
         private readonly int sourceLength;
 
         private readonly double ratio;
@@ -41,7 +37,6 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
         private ResizeKernelMap(
             MemoryAllocator memoryAllocator,
-            TResampler sampler,
             int sourceLength,
             int destinationLength,
             int bufferHeight,
@@ -49,7 +44,6 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             double scale,
             int radius)
         {
-            this.sampler = sampler;
             this.ratio = ratio;
             this.scale = scale;
             this.radius = radius;
@@ -79,7 +73,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             $"radius:{this.radius}|sourceSize:{this.sourceLength}|destinationSize:{this.DestinationLength}|ratio:{this.ratio}|scale:{this.scale}";
 
         /// <summary>
-        /// Disposes <see cref="ResizeKernelMap{TResampler}"/> instance releasing it's backing buffer.
+        /// Disposes <see cref="ResizeKernelMap"/> instance releasing it's backing buffer.
         /// </summary>
         public void Dispose()
             => this.Dispose(true);
@@ -111,16 +105,18 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         /// <summary>
         /// Computes the weights to apply at each pixel when resizing.
         /// </summary>
+        /// <typeparam name="TResampler">The type of sampler.</typeparam>
         /// <param name="sampler">The <see cref="IResampler"/></param>
         /// <param name="destinationSize">The destination size</param>
         /// <param name="sourceSize">The source size</param>
         /// <param name="memoryAllocator">The <see cref="MemoryAllocator"/> to use for buffer allocations</param>
-        /// <returns>The <see cref="ResizeKernelMap{IResampler}"/></returns>
-        public static ResizeKernelMap<TResampler> Calculate(
+        /// <returns>The <see cref="ResizeKernelMap"/></returns>
+        public static ResizeKernelMap Calculate<TResampler>(
             in TResampler sampler,
             int destinationSize,
             int sourceSize,
             MemoryAllocator memoryAllocator)
+            where TResampler : unmanaged, IResampler
         {
             double ratio = (double)sourceSize / destinationSize;
             double scale = ratio;
@@ -158,10 +154,9 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             // If we don't have at least 2 periods, we go with the basic implementation:
             bool hasAtLeast2Periods = 2 * (cornerInterval + period) < destinationSize;
 
-            ResizeKernelMap<TResampler> result = hasAtLeast2Periods
+            ResizeKernelMap result = hasAtLeast2Periods
                                          ? new PeriodicKernelMap(
                                              memoryAllocator,
-                                             sampler,
                                              sourceSize,
                                              destinationSize,
                                              ratio,
@@ -169,9 +164,8 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
                                              radius,
                                              period,
                                              cornerInterval)
-                                         : new ResizeKernelMap<TResampler>(
+                                         : new ResizeKernelMap(
                                              memoryAllocator,
-                                             sampler,
                                              sourceSize,
                                              destinationSize,
                                              destinationSize,
@@ -179,7 +173,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
                                              scale,
                                              radius);
 
-            result.Initialize();
+            result.Initialize(in sampler);
 
             return result;
         }
@@ -187,11 +181,12 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         /// <summary>
         /// Initializes the kernel map.
         /// </summary>
-        protected internal virtual void Initialize()
+        protected internal virtual void Initialize<TResampler>(in TResampler sampler)
+            where TResampler : unmanaged, IResampler
         {
             for (int i = 0; i < this.DestinationLength; i++)
             {
-                this.kernels[i] = this.BuildKernel(i, i);
+                this.kernels[i] = this.BuildKernel(in sampler, i, i);
             }
         }
 
@@ -200,7 +195,8 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         /// referencing the data at row <paramref name="dataRowIndex"/> within <see cref="data"/>,
         /// so the data reusable by other data rows.
         /// </summary>
-        private ResizeKernel BuildKernel(int destRowIndex, int dataRowIndex)
+        private ResizeKernel BuildKernel<TResampler>(in TResampler sampler, int destRowIndex, int dataRowIndex)
+            where TResampler : unmanaged, IResampler
         {
             double center = ((destRowIndex + .5) * this.ratio) - .5;
 
@@ -224,7 +220,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
             for (int j = left; j <= right; j++)
             {
-                double value = this.sampler.GetValue((float)((j - center) / this.scale));
+                double value = sampler.GetValue((float)((j - center) / this.scale));
                 sum += value;
 
                 kernelValues[j - left] = value;

src/ImageSharp/Processing/Processors/Transforms/Resize/ResizeWorker.cs

@@ -6,7 +6,6 @@ using System.Buffers;
 using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
-
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
 
@@ -19,8 +18,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
     /// When sliding the window, the contents of the bottom window band are copied to the new top band.
     /// For more details, and visual explanation, see "ResizeWorker.pptx".
     /// </summary>
-    internal sealed class ResizeWorker<TResampler, TPixel> : IDisposable
-        where TResampler : unmanaged, IResampler
+    internal sealed class ResizeWorker<TPixel> : IDisposable
         where TPixel : struct, IPixel<TPixel>
     {
         private readonly Buffer2D<Vector4> transposedFirstPassBuffer;
@@ -29,7 +27,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
         private readonly PixelConversionModifiers conversionModifiers;
 
-        private readonly ResizeKernelMap<TResampler> horizontalKernelMap;
+        private readonly ResizeKernelMap horizontalKernelMap;
 
         private readonly BufferArea<TPixel> source;
 
@@ -39,7 +37,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
 
         private readonly IMemoryOwner<Vector4> tempColumnBuffer;
 
-        private readonly ResizeKernelMap<TResampler> verticalKernelMap;
+        private readonly ResizeKernelMap verticalKernelMap;
 
         private readonly int destWidth;
 
@@ -57,8 +55,8 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             Configuration configuration,
             BufferArea<TPixel> source,
             PixelConversionModifiers conversionModifiers,
-            ResizeKernelMap<TResampler> horizontalKernelMap,
-            ResizeKernelMap<TResampler> verticalKernelMap,
+            ResizeKernelMap horizontalKernelMap,
+            ResizeKernelMap verticalKernelMap,
             int destWidth,
             Rectangle targetWorkingRect,
             Point targetOrigin)

tests/ImageSharp.Tests/Processing/Processors/Transforms/ResizeKernelMapTests.ReferenceKernelMap.cs

@@ -13,8 +13,7 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
         /// <summary>
         /// Simplified reference implementation for <see cref="ResizeKernelMap"/> functionality.
         /// </summary>
-        internal class ReferenceKernelMap<TResampler>
-            where TResampler : unmanaged, IResampler
+        internal class ReferenceKernelMap
         {
             private readonly ReferenceKernel[] kernels;
 
@@ -27,7 +26,8 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
 
             public ReferenceKernel GetKernel(int destinationIndex) => this.kernels[destinationIndex];
 
-            public static ReferenceKernelMap<TResampler> Calculate(TResampler sampler, int destinationSize, int sourceSize, bool normalize = true)
+            public static ReferenceKernelMap Calculate<TResampler>(in TResampler sampler, int destinationSize, int sourceSize, bool normalize = true)
+                where TResampler : unmanaged, IResampler
             {
                 double ratio = (double)sourceSize / destinationSize;
                 double scale = ratio;
@@ -85,7 +85,7 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
                     result.Add(new ReferenceKernel(left, floatVals));
                 }
 
-                return new ReferenceKernelMap<TResampler>(result.ToArray());
+                return new ReferenceKernelMap(result.ToArray());
             }
         }
 

tests/ImageSharp.Tests/Processing/Processors/Transforms/ResizeKernelMapTests.cs

@@ -89,7 +89,7 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
         public void PrintNonNormalizedKernelMap<TResampler>(TResampler resampler, int srcSize, int destSize)
             where TResampler : unmanaged, IResampler
         {
-            var kernelMap = ReferenceKernelMap<TResampler>.Calculate(resampler, destSize, srcSize, false);
+            var kernelMap = ReferenceKernelMap.Calculate<TResampler>(in resampler, destSize, srcSize, false);
 
             this.Output.WriteLine($"Actual KernelMap:\n{PrintKernelMap(kernelMap)}\n");
         }
@@ -117,8 +117,8 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
         private void VerifyKernelMapContentIsCorrect<TResampler>(TResampler resampler, int srcSize, int destSize)
             where TResampler : unmanaged, IResampler
         {
-            var referenceMap = ReferenceKernelMap<TResampler>.Calculate(resampler, destSize, srcSize);
-            var kernelMap = ResizeKernelMap<TResampler>.Calculate(resampler, destSize, srcSize, Configuration.Default.MemoryAllocator);
+            var referenceMap = ReferenceKernelMap.Calculate(in resampler, destSize, srcSize);
+            var kernelMap = ResizeKernelMap.Calculate(in resampler, destSize, srcSize, Configuration.Default.MemoryAllocator);
 
 #if DEBUG
             this.Output.WriteLine(kernelMap.Info);
@@ -153,23 +153,20 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
             }
         }
 
-        private static string PrintKernelMap<TResampler>(ResizeKernelMap<TResampler> kernelMap)
-            where TResampler : unmanaged, IResampler
-            => PrintKernelMap<TResampler, ResizeKernelMap<TResampler>>(kernelMap, km => km.DestinationLength, (km, i) => km.GetKernel(i));
+        private static string PrintKernelMap(ResizeKernelMap kernelMap)
+            => PrintKernelMap(kernelMap, km => km.DestinationLength, (km, i) => km.GetKernel(i));
 
-        private static string PrintKernelMap<TResampler>(ReferenceKernelMap<TResampler> kernelMap)
-            where TResampler : unmanaged, IResampler
-            => PrintKernelMap<TResampler, ReferenceKernelMap<TResampler>>(kernelMap, km => km.DestinationSize, (km, i) => km.GetKernel(i));
+        private static string PrintKernelMap(ReferenceKernelMap kernelMap)
+            => PrintKernelMap(kernelMap, km => km.DestinationSize, (km, i) => km.GetKernel(i));
 
-        private static string PrintKernelMap<TResampler, TKernelMap>(
+        private static string PrintKernelMap<TKernelMap>(
             TKernelMap kernelMap,
             Func<TKernelMap, int> getDestinationSize,
             Func<TKernelMap, int, ReferenceKernel> getKernel)
-            where TResampler : unmanaged, IResampler
         {
             var bld = new StringBuilder();
 
-            if (kernelMap is ResizeKernelMap<TResampler> actualMap)
+            if (kernelMap is ResizeKernelMap actualMap)
             {
                 bld.AppendLine(actualMap.Info);
             }

tests/ImageSharp.Tests/Processing/Processors/Transforms/ResizeTests.cs

@@ -121,7 +121,7 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
                 configuration.MemoryAllocator = allocator;
                 configuration.WorkingBufferSizeHintInBytes = workingBufferSizeHintInBytes;
 
-                var verticalKernelMap = ResizeKernelMap<BicubicResampler>.Calculate(
+                var verticalKernelMap = ResizeKernelMap.Calculate<BicubicResampler>(
                     default,
                     destSize.Height,
                     image0.Height,