Update generator to emit 'EffectFactory' property

Author: Sergio0694

src/ComputeSharp.D2D1.SourceGenerators/D2DPixelShaderDescriptorGenerator.EffectFactory.Syntax.cs

@@ -0,0 +1,46 @@
+using ComputeSharp.D2D1.SourceGenerators.Models;
+using ComputeSharp.SourceGeneration.Extensions;
+using ComputeSharp.SourceGeneration.Helpers;
+
+namespace ComputeSharp.D2D1.SourceGenerators;
+
+/// <inheritdoc/>
+partial class D2DPixelShaderDescriptorGenerator
+{
+    /// <summary>
+    /// A helper with all logic to generate the <c>EffectFactory</c> property.
+    /// </summary>
+    private static class EffectFactory
+    {
+        /// <summary>
+        /// Writes the <c>EffectFactory</c> property.
+        /// </summary>
+        /// <param name="info">The input <see cref="D2D1ShaderInfo"/> instance with gathered shader info.</param>
+        /// <param name="writer">The <see cref="IndentedTextWriter"/> instance to write into.</param>
+        public static void WriteSyntax(D2D1ShaderInfo info, IndentedTextWriter writer)
+        {
+            writer.WriteLine("/// <inheritdoc/>");
+            writer.WriteGeneratedAttributes(GeneratorName);
+            writer.WriteLine($"static unsafe nint global::ComputeSharp.D2D1.Descriptors.ID2D1PixelShaderDescriptor<{info.Hierarchy.Hierarchy[0].QualifiedName}>.EffectFactory");
+
+            using (writer.WriteBlock())
+            {
+                writer.WriteLine("[global::System.Runtime.CompilerServices.MethodImpl(global::System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]");
+                writer.WriteLine("get");
+
+                using (writer.WriteBlock())
+                {
+                    writer.WriteLine($$"""
+                        [global::System.Runtime.InteropServices.UnmanagedCallersOnly(CallConvs = [typeof(global::System.Runtime.CompilerServices.CallConvStdcall)])]
+                        static int FactoryDelegate(void** effectImpl)
+                        {
+                            return global::ComputeSharp.D2D1.Interop.D2D1PixelShaderEffect.CreateEffectUnsafe<{{info.Hierarchy.Hierarchy[0].QualifiedName}}>(effectImpl);
+                        }
+
+                        return (nint)(delegate* unmanaged[Stdcall]<void**, int>)&FactoryDelegate;
+                        """, isMultiline: true);
+                }
+            }
+        }
+    }
+}

src/ComputeSharp.D2D1.SourceGenerators/D2DPixelShaderDescriptorGenerator.cs

@@ -225,6 +225,7 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
             declaredMembers.Add(EffectMetadata.WriteEffectDescriptionSyntax);
             declaredMembers.Add(EffectMetadata.WriteEffectCategorySyntax);
             declaredMembers.Add(EffectMetadata.WriteEffectAuthorSyntax);
+            declaredMembers.Add(EffectFactory.WriteSyntax);
             declaredMembers.Add(NumericProperties.WriteConstantBufferSizeSyntax);
             declaredMembers.Add(NumericProperties.WriteInputCountSyntax);
             declaredMembers.Add(NumericProperties.WriteResourceTextureCountSyntax);