started the refactor

src/ImageSharp.Drawing/Processing/DrawingHelpers.cs

@@ -0,0 +1,19 @@
+// // Copyright (c) Six Labors and contributors.
+// // Licensed under the Apache License, Version 2.0.
+
+using SixLabors.ImageSharp.PixelFormats;
+using SixLabors.ImageSharp.Primitives;
+
+namespace SixLabors.ImageSharp.Processing
+{
+    internal static class DrawingHelpers
+    {
+        public static DenseMatrix<TPixel> ToPixelMatrix<TPixel>(this DenseMatrix<Color> colorMatrix, Configuration configuration)
+            where TPixel : struct, IPixel<TPixel>
+        {
+            DenseMatrix<TPixel> result = new DenseMatrix<TPixel>(colorMatrix.Columns, colorMatrix.Rows);
+            Color.ToPixel(configuration, colorMatrix.Span, result.Span);
+            return result;
+        }
+    }
+}

src/ImageSharp.Drawing/Processing/IBrush.cs

@@ -14,8 +14,7 @@ namespace SixLabors.ImageSharp.Processing
     /// A brush is a simple class that will return an <see cref="BrushApplicator{TPixel}" /> that will perform the
     /// logic for converting a pixel location to a <typeparamref name="TPixel"/>.
     /// </remarks>
-    public interface IBrush<TPixel>
-        where TPixel : struct, IPixel<TPixel>
+    public interface IBrush
     {
         /// <summary>
         /// Creates the applicator for this brush.
@@ -30,6 +29,10 @@ namespace SixLabors.ImageSharp.Processing
         /// The <paramref name="region" /> when being applied to things like shapes would usually be the
         /// bounding box of the shape not necessarily the bounds of the whole image
         /// </remarks>
-        BrushApplicator<TPixel> CreateApplicator(ImageFrame<TPixel> source, RectangleF region, GraphicsOptions options);
+        BrushApplicator<TPixel> CreateApplicator<TPixel>(
+            ImageFrame<TPixel> source,
+            RectangleF region,
+            GraphicsOptions options)
+            where TPixel : struct, IPixel<TPixel>;
     }
 }

src/ImageSharp.Drawing/Processing/IPen.cs

@@ -7,23 +7,15 @@ using SixLabors.ImageSharp.PixelFormats;
 namespace SixLabors.ImageSharp.Processing
 {
     /// <summary>
-    /// Interface representing a Pen
+    /// Interface representing the pattern and size of the stroke to apply with a Pen.
     /// </summary>
-    /// <typeparam name="TPixel">The type of the color.</typeparam>
-    public interface IPen<TPixel> : IPen
-            where TPixel : struct, IPixel<TPixel>
+    public interface IPen
     {
         /// <summary>
         /// Gets the stroke fill.
         /// </summary>
-        IBrush<TPixel> StrokeFill { get; }
-    }
-
-    /// <summary>
-    /// Interface representing the pattern and size of the stroke to apply with a Pen.
-    /// </summary>
-    public interface IPen
-    {
+        IBrush StrokeFill { get; }
+        
         /// <summary>
         /// Gets the width to apply to the stroke
         /// </summary>

src/ImageSharp.Drawing/Processing/PatternBrush{TPixel}.cs

@@ -35,13 +35,12 @@ namespace SixLabors.ImageSharp.Processing
     /// </para>
     /// </remarks>
     /// <typeparam name="TPixel">The pixel format.</typeparam>
-    public class PatternBrush<TPixel> : IBrush<TPixel>
-        where TPixel : struct, IPixel<TPixel>
+    public class PatternBrush : IBrush
     {
         /// <summary>
         /// The pattern.
         /// </summary>
-        private readonly DenseMatrix<TPixel> pattern;
+        private readonly DenseMatrix<Color> pattern;
         private readonly DenseMatrix<Vector4> patternVector;
 
         /// <summary>
@@ -50,7 +49,7 @@ namespace SixLabors.ImageSharp.Processing
         /// <param name="foreColor">Color of the fore.</param>
         /// <param name="backColor">Color of the back.</param>
         /// <param name="pattern">The pattern.</param>
-        public PatternBrush(TPixel foreColor, TPixel backColor, bool[,] pattern)
+        public PatternBrush(Color foreColor, Color backColor, bool[,] pattern)
             : this(foreColor, backColor, new DenseMatrix<bool>(pattern))
         {
         }
@@ -61,11 +60,11 @@ namespace SixLabors.ImageSharp.Processing
         /// <param name="foreColor">Color of the fore.</param>
         /// <param name="backColor">Color of the back.</param>
         /// <param name="pattern">The pattern.</param>
-        internal PatternBrush(TPixel foreColor, TPixel backColor, in DenseMatrix<bool> pattern)
+        internal PatternBrush(Color foreColor, Color backColor, in DenseMatrix<bool> pattern)
         {
             var foreColorVector = foreColor.ToVector4();
             var backColorVector = backColor.ToVector4();
-            this.pattern = new DenseMatrix<TPixel>(pattern.Columns, pattern.Rows);
+            this.pattern = new DenseMatrix<Color>(pattern.Columns, pattern.Rows);
             this.patternVector = new DenseMatrix<Vector4>(pattern.Columns, pattern.Rows);
             for (int i = 0; i < pattern.Data.Length; i++)
             {
@@ -86,19 +85,25 @@ namespace SixLabors.ImageSharp.Processing
         /// Initializes a new instance of the <see cref="PatternBrush{TPixel}"/> class.
         /// </summary>
         /// <param name="brush">The brush.</param>
-        internal PatternBrush(PatternBrush<TPixel> brush)
+        internal PatternBrush(PatternBrush<Color> brush)
         {
             this.pattern = brush.pattern;
             this.patternVector = brush.patternVector;
         }
 
         /// <inheritdoc />
-        public BrushApplicator<TPixel> CreateApplicator(ImageFrame<TPixel> source, RectangleF region, GraphicsOptions options) => new PatternBrushApplicator(source, this.pattern, this.patternVector, options);
+        public BrushApplicator<TPixel> CreateApplicator<TPixel>(
+            ImageFrame<TPixel> source,
+            RectangleF region,
+            GraphicsOptions options)
+            where TPixel : struct, IPixel<TPixel> =>
+            new PatternBrushApplicator<TPixel>(source, this.pattern, this.patternVector, options);
 
         /// <summary>
         /// The pattern brush applicator.
         /// </summary>
-        private class PatternBrushApplicator : BrushApplicator<TPixel>
+        private class PatternBrushApplicator<TPixel> : BrushApplicator<TPixel>
+            where TPixel : struct, IPixel<TPixel>
         {
             /// <summary>
             /// The pattern.
@@ -107,16 +112,17 @@ namespace SixLabors.ImageSharp.Processing
             private readonly DenseMatrix<Vector4> patternVector;
 
             /// <summary>
-            /// Initializes a new instance of the <see cref="PatternBrushApplicator" /> class.
+            /// Initializes a new instance of the <see cref="PatternBrushApplicator{TPixel}" /> class.
             /// </summary>
             /// <param name="source">The source image.</param>
             /// <param name="pattern">The pattern.</param>
             /// <param name="patternVector">The patternVector.</param>
             /// <param name="options">The options</param>
-            public PatternBrushApplicator(ImageFrame<TPixel> source, in DenseMatrix<TPixel> pattern, DenseMatrix<Vector4> patternVector, GraphicsOptions options)
+            public PatternBrushApplicator(ImageFrame<TPixel> source, in DenseMatrix<Color> pattern, DenseMatrix<Vector4> patternVector, GraphicsOptions options)
                 : base(source, options)
             {
-                this.pattern = pattern;
+                this.pattern = new DenseMatrix<TPixel>(pattern.Columns, pattern.Rows);
+                Color.ToPixel<TPixel>(source.Configuration, pattern.Data, this.pattern.Data);
                 this.patternVector = patternVector;
             }
 

src/ImageSharp.Drawing/Processing/SolidBrush{TPixel}.cs

@@ -15,20 +15,18 @@ namespace SixLabors.ImageSharp.Processing
     /// <summary>
     /// Provides an implementation of a solid brush for painting solid color areas.
     /// </summary>
-    /// <typeparam name="TPixel">The pixel format.</typeparam>
-    public class SolidBrush<TPixel> : IBrush<TPixel>
-        where TPixel : struct, IPixel<TPixel>
+    public class SolidBrush : IBrush
     {
         /// <summary>
         /// The color to paint.
         /// </summary>
-        private readonly TPixel color;
+        private readonly Color color;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="SolidBrush{TPixel}"/> class.
         /// </summary>
         /// <param name="color">The color.</param>
-        public SolidBrush(TPixel color)
+        public SolidBrush(Color color)
         {
             this.color = color;
         }
@@ -39,18 +37,20 @@ namespace SixLabors.ImageSharp.Processing
         /// <value>
         /// The color.
         /// </value>
-        public TPixel Color => this.color;
+        public Color Color => this.color;
 
         /// <inheritdoc />
-        public BrushApplicator<TPixel> CreateApplicator(ImageFrame<TPixel> source, RectangleF region, GraphicsOptions options)
+        public BrushApplicator<TPixel> CreateApplicator<TPixel>(ImageFrame<TPixel> source, RectangleF region, GraphicsOptions options)
+            where TPixel : struct, IPixel<TPixel>
         {
-            return new SolidBrushApplicator(source, this.color, options);
+            return new SolidBrushApplicator<TPixel>(source, this.color.ToPixel<TPixel>(), options);
         }
 
         /// <summary>
         /// The solid brush applicator.
         /// </summary>
-        private class SolidBrushApplicator : BrushApplicator<TPixel>
+        private class SolidBrushApplicator<TPixel> : BrushApplicator<TPixel>
+            where TPixel : struct, IPixel<TPixel>
         {
             /// <summary>
             /// Initializes a new instance of the <see cref="SolidBrushApplicator"/> class.

src/ImageSharp/Color/Color.Conversions.cs

@@ -91,5 +91,8 @@ namespace SixLabors.ImageSharp
 
         [MethodImpl(InliningOptions.ShortMethod)]
         internal Bgr24 ToBgr24() => this.data.ToBgr24();
+
+        [MethodImpl(InliningOptions.ShortMethod)]
+        internal Vector4 ToVector4() => this.data.ToVector4();
     }
 }