Blaze style works.

Author: JimBobSquarePants

ImageSharp.Drawing.sln

@@ -339,6 +339,8 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "workflows", "workflows", "{
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "PolygonClipper", "..\..\SixLabors\PolygonClipper\src\PolygonClipper\PolygonClipper.csproj", "{5ED54794-99BF-5E50-A861-0BAAAC794E44}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ImageSharp", "..\..\SixLabors\ImageSharp\src\ImageSharp\ImageSharp.csproj", "{AAF7501C-8537-7F13-5193-B538318BD071}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -365,6 +367,10 @@ Global
 		{5ED54794-99BF-5E50-A861-0BAAAC794E44}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{5ED54794-99BF-5E50-A861-0BAAAC794E44}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{5ED54794-99BF-5E50-A861-0BAAAC794E44}.Release|Any CPU.Build.0 = Release|Any CPU
+		{AAF7501C-8537-7F13-5193-B538318BD071}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{AAF7501C-8537-7F13-5193-B538318BD071}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{AAF7501C-8537-7F13-5193-B538318BD071}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{AAF7501C-8537-7F13-5193-B538318BD071}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -393,6 +399,7 @@ Global
 		{5493F024-0A3F-420C-AC2D-05B77A36025B} = {528610AC-7C0C-46E8-9A2D-D46FD92FEE29}
 		{23859314-5693-4E6C-BE5C-80A433439D2A} = {1799C43E-5C54-4A8F-8D64-B1475241DB0D}
 		{5ED54794-99BF-5E50-A861-0BAAAC794E44} = {815C0625-CD3D-440F-9F80-2D83856AB7AE}
+		{AAF7501C-8537-7F13-5193-B538318BD071} = {815C0625-CD3D-440F-9F80-2D83856AB7AE}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {5F8B9D1F-CD8B-4CC5-8216-D531E25BD795}
@@ -401,6 +408,7 @@ Global
 		shared-infrastructure\src\SharedInfrastructure\SharedInfrastructure.projitems*{2e33181e-6e28-4662-a801-e2e7dc206029}*SharedItemsImports = 5
 		..\..\SixLabors\PolygonClipper\shared-infrastructure\src\SharedInfrastructure\SharedInfrastructure.projitems*{5ed54794-99bf-5e50-a861-0baaac794e44}*SharedItemsImports = 5
 		shared-infrastructure\src\SharedInfrastructure\SharedInfrastructure.projitems*{68a8cc40-6aed-4e96-b524-31b1158fdeea}*SharedItemsImports = 13
+		..\..\SixLabors\ImageSharp\shared-infrastructure\src\SharedInfrastructure\SharedInfrastructure.projitems*{aaf7501c-8537-7f13-5193-b538318bd071}*SharedItemsImports = 5
 	EndGlobalSection
 	GlobalSection(Performance) = preSolution
 		HasPerformanceSessions = true

src/ImageSharp.Drawing/Processing/Backends/CpuDrawingBackend.cs

@@ -0,0 +1,72 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using System;
+using SixLabors.ImageSharp.Drawing.Shapes.Rasterization;
+using SixLabors.ImageSharp.Memory;
+
+namespace SixLabors.ImageSharp.Drawing.Processing.Backends;
+
+/// <summary>
+/// Default CPU drawing backend.
+/// </summary>
+/// <remarks>
+/// This backend currently dispatches to the existing scanline rasterizer pipeline.
+/// A tiled rasterizer path is wired behind an AppContext switch for incremental rollout.
+/// </remarks>
+internal sealed class CpuDrawingBackend : IDrawingBackend
+{
+    private const string ExperimentalTiledRasterizerSwitch = "SixLabors.ImageSharp.Drawing.ExperimentalTiledRasterizer";
+
+    private readonly IRasterizer defaultRasterizer;
+    private readonly TiledRasterizer tiledRasterizer;
+
+    private CpuDrawingBackend(IRasterizer defaultRasterizer)
+    {
+        Guard.NotNull(defaultRasterizer, nameof(defaultRasterizer));
+        this.defaultRasterizer = defaultRasterizer;
+        this.tiledRasterizer = TiledRasterizer.Instance;
+    }
+
+    /// <summary>
+    /// Gets the default backend instance.
+    /// </summary>
+    public static CpuDrawingBackend Instance { get; } = new(DefaultRasterizer.Instance);
+
+    /// <summary>
+    /// Gets the primary rasterizer used by this backend.
+    /// </summary>
+    public IRasterizer PrimaryRasterizer => this.defaultRasterizer;
+
+    /// <summary>
+    /// Creates a backend that uses the given rasterizer as the primary implementation.
+    /// </summary>
+    /// <param name="rasterizer">Primary rasterizer.</param>
+    /// <returns>A backend instance.</returns>
+    public static CpuDrawingBackend Create(IRasterizer rasterizer)
+    {
+        Guard.NotNull(rasterizer, nameof(rasterizer));
+        return ReferenceEquals(rasterizer, DefaultRasterizer.Instance) ? Instance : new CpuDrawingBackend(rasterizer);
+    }
+
+    /// <inheritdoc />
+    public void RasterizePath<TState>(
+        IPath path,
+        in RasterizerOptions options,
+        MemoryAllocator allocator,
+        ref TState state,
+        RasterizerScanlineHandler<TState> scanlineHandler)
+        where TState : struct
+    {
+        if (UseExperimentalTiledRasterizer())
+        {
+            this.tiledRasterizer.Rasterize(path, options, allocator, ref state, scanlineHandler);
+            return;
+        }
+
+        this.defaultRasterizer.Rasterize(path, options, allocator, ref state, scanlineHandler);
+    }
+
+    private static bool UseExperimentalTiledRasterizer()
+        => AppContext.TryGetSwitch(ExperimentalTiledRasterizerSwitch, out bool enabled) && enabled;
+}

src/ImageSharp.Drawing/Processing/Backends/IDrawingBackend.cs

@@ -0,0 +1,34 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using SixLabors.ImageSharp.Drawing.Shapes.Rasterization;
+using SixLabors.ImageSharp.Memory;
+
+namespace SixLabors.ImageSharp.Drawing.Processing.Backends;
+
+/// <summary>
+/// Internal drawing backend abstraction used by processors.
+/// </summary>
+/// <remarks>
+/// This boundary allows processor logic to stay stable while the implementation evolves
+/// (for example: alternate CPU rasterizers or eventual non-CPU backends).
+/// </remarks>
+internal interface IDrawingBackend
+{
+    /// <summary>
+    /// Rasterizes a path into scanline coverage.
+    /// </summary>
+    /// <typeparam name="TState">The caller-provided mutable state type.</typeparam>
+    /// <param name="path">The path to rasterize.</param>
+    /// <param name="options">Rasterizer options.</param>
+    /// <param name="allocator">Allocator for temporary data.</param>
+    /// <param name="state">Caller-owned mutable state passed to the scanline callback.</param>
+    /// <param name="scanlineHandler">Scanline callback.</param>
+    void RasterizePath<TState>(
+        IPath path,
+        in RasterizerOptions options,
+        MemoryAllocator allocator,
+        ref TState state,
+        RasterizerScanlineHandler<TState> scanlineHandler)
+        where TState : struct;
+}

src/ImageSharp.Drawing/Processing/Processors/Drawing/FillPathProcessor.cs

@@ -12,9 +12,10 @@ namespace SixLabors.ImageSharp.Drawing.Processing.Processors.Drawing;
 public class FillPathProcessor : IImageProcessor
 {
     /// <summary>
-    /// Minimum subpixel count for rasterization, being applied even if antialiasing is off.
+    /// Fixed subpixel sampling density used by the CPU rasterizer for both antialiased and
+    /// quantized-aliased rendering.
     /// </summary>
-    internal const int MinimumSubpixelCount = 8;
+    internal const int FixedRasterizerSubpixelCount = 16;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="FillPathProcessor" /> class.