feat(render): add view blend modes

Example/Shared/Render/RendererEffect/BlendModeExample.swift

@@ -0,0 +1,33 @@
+//
+//  BlendModeExample.swift
+//  Shared
+
+#if OPENSWIFTUI
+import OpenSwiftUI
+#else
+import SwiftUI
+#endif
+
+struct BlendModeExample: View {
+    var body: some View {
+        BlendModeRectanglesExample(blendMode: .colorBurn)
+    }
+}
+
+struct BlendModeRectanglesExample: View {
+    var blendMode: BlendMode
+
+    var body: some View {
+        HStack {
+            Color.yellow.frame(width: 50, height: 50, alignment: .center)
+            Color.red.frame(width: 50, height: 50, alignment: .center)
+                .rotationEffect(.degrees(45))
+                .padding(-20)
+                .blendMode(blendMode)
+        }
+    }
+}
+
+#Preview {
+    BlendModeExample()
+}

Example/Tests/OpenSwiftUIUITests/Render/RendererEffect/BlendModeEffectUITests.swift

@@ -0,0 +1,44 @@
+//
+//  BlendModeEffectUITests.swift
+//  OpenSwiftUIUITests
+
+import SnapshotTesting
+import Testing
+@testable import TestingHost
+
+@MainActor
+@Suite(.snapshots(record: .never, diffTool: diffTool))
+struct BlendModeEffectUITests {
+    @Test(
+        arguments: [
+            (.normal, "normal"),
+            (.multiply, "multiply"),
+            (.screen, "screen"),
+            (.overlay, "overlay"),
+            (.darken, "darken"),
+            (.lighten, "lighten"),
+            (.colorDodge, "colorDodge"),
+            (.colorBurn, "colorBurn"),
+            (.softLight, "softLight"),
+            (.hardLight, "hardLight"),
+            (.difference, "difference"),
+            (.exclusion, "exclusion"),
+            (.hue, "hue"),
+            (.saturation, "saturation"),
+            (.color, "color"),
+            (.luminosity, "luminosity"),
+            (.sourceAtop, "sourceAtop"),
+            (.destinationOver, "destinationOver"),
+            (.destinationOut, "destinationOut"),
+            (.plusDarker, "plusDarker"),
+            (.plusLighter, "plusLighter"),
+        ] as [(BlendMode, String)]
+    )
+    func blendMode(_ blendMode: BlendMode, name: String) {
+        openSwiftUIAssertSnapshot(
+            of: BlendModeRectanglesExample(blendMode: blendMode),
+            drawHierarchyInKeyWindow: true,
+            testName: "blend_mode_\(name)"
+        )
+    }
+}

Sources/OpenSwiftUICore/Graphic/GraphicsFilter.swift

@@ -7,6 +7,9 @@
 
 package import OpenCoreGraphicsShims
 import OpenQuartzCoreShims
+#if canImport(QuartzCore)
+import QuartzCore_Private
+#endif
 
 package enum GraphicsFilter {
     case blur(BlurStyle)
@@ -141,14 +144,19 @@ package enum GraphicsBlendMode: Equatable {
     }
 
     @inline(__always)
-    var filter: Any? {
+    func filter(compositingGroup: Bool) -> Any? {
         switch self {
         case let .caFilter(filter):
             return filter
         case let .blendMode(mode):
-            // TODO: _ORBBlendModeGetCompositingFilter & ORBBlendMode
-            _openSwiftUIUnimplementedWarning()
+            #if canImport(QuartzCore)
+            return ORBBlendModeGetCompositingFilter(
+                .init(rawValue: mode.rawValue),
+                compositingGroup: compositingGroup
+            )
+            #else
             return nil
+            #endif
         }
     }
 }

Sources/OpenSwiftUICore/Render/DisplayList/DisplayListViewPlatform.swift

@@ -1036,7 +1036,7 @@ extension DisplayList.ViewUpdater.Platform {
             CoreViewSetCompositingFilter(
                 system: viewSystem,
                 view: viewInfo.view,
-                filter: state.pointee.blend.filter
+                filter: state.pointee.blend.filter(compositingGroup: state.pointee.compositingGroup)
             )
             viewInfo.seeds.blend = state.pointee.versions.blend.seed
         }

Sources/OpenSwiftUICore/Render/RendererEffect/BlendModeEffect.swift

@@ -0,0 +1,118 @@
+//
+//  BlendModeEffect.swift
+//  OpenSwiftUICore
+//
+//  Audited for 6.5.4
+//  Status: Complete
+
+package import Foundation
+
+// MARK: - _BlendModeEffect
+
+@available(OpenSwiftUI_v1_0, *)
+@frozen
+@MainActor
+@preconcurrency
+public struct _BlendModeEffect: RendererEffect, Equatable {
+    public var blendMode: BlendMode
+
+    @inlinable
+    nonisolated public init(blendMode: BlendMode) {
+        self.blendMode = blendMode
+    }
+
+    package func effectValue(size: CGSize) -> DisplayList.Effect {
+        .blendMode(GraphicsBlendMode(blendMode))
+    }
+}
+
+@available(*, unavailable)
+extension _BlendModeEffect: Sendable {}
+
+// MARK: - _ExtendedBlendModeEffect
+
+@_spi(Private)
+@available(OpenSwiftUI_v3_0, *)
+@frozen
+@MainActor
+@preconcurrency
+public struct _ExtendedBlendModeEffect: RendererEffect, Equatable {
+    public var blendMode: GraphicsContext.BlendMode
+
+    @inlinable
+    public init(blendMode: GraphicsContext.BlendMode) {
+        self.blendMode = blendMode
+    }
+
+    package func effectValue(size: CGSize) -> DisplayList.Effect {
+        .blendMode(.blendMode(blendMode))
+    }
+}
+
+// MARK: - View + blendMode
+
+@available(OpenSwiftUI_v1_0, *)
+extension View {
+    /// Sets the blend mode for compositing this view with overlapping views.
+    ///
+    /// Use `blendMode(_:)` to combine overlapping views and use a different
+    /// visual effect to produce the result. The ``BlendMode`` enumeration
+    /// defines many possible effects.
+    ///
+    /// In the example below, the two overlapping rectangles have a
+    /// ``BlendMode/colorBurn`` effect applied, which effectively removes the
+    /// non-overlapping portion of the second image:
+    ///
+    ///     HStack {
+    ///         Color.yellow.frame(width: 50, height: 50, alignment: .center)
+    ///
+    ///         Color.red.frame(width: 50, height: 50, alignment: .center)
+    ///             .rotationEffect(.degrees(45))
+    ///             .padding(-20)
+    ///             .blendMode(.colorBurn)
+    ///     }
+    ///
+    /// ![Two overlapping rectangles showing the effect of the blend mode view
+    /// modifier applying the colorBurn effect.](OpenSwiftUI-blendMode)
+    ///
+    /// - Parameter blendMode: The ``BlendMode`` for compositing this view.
+    ///
+    /// - Returns: A view that applies `blendMode` to this view.
+    @inlinable
+    nonisolated public func blendMode(_ blendMode: BlendMode) -> some View {
+        modifier(_BlendModeEffect(blendMode: blendMode))
+    }
+}
+
+// MARK: - View + extendedBlendMode
+
+@_spi(Private)
+@available(OpenSwiftUI_v3_0, *)
+extension View {
+    @inlinable
+    nonisolated public func extendedBlendMode(_ blendMode: GraphicsContext.BlendMode) -> some View {
+        modifier(_ExtendedBlendModeEffect(blendMode: blendMode))
+    }
+}
+
+// MARK: - View + graphicsBlendMode
+
+extension View {
+    @MainActor
+    @preconcurrency
+    package func graphicsBlendMode(_ blendMode: GraphicsBlendMode) -> some View {
+        modifier(GraphicsBlendModeEffect(blendMode: blendMode))
+    }
+}
+
+// MARK: - GraphicsBlendModeEffect
+
+@MainActor
+@preconcurrency
+struct GraphicsBlendModeEffect: RendererEffect {
+    var blendMode: GraphicsBlendMode
+
+    func effectValue(size: CGSize) -> DisplayList.Effect {
+        .blendMode(blendMode)
+    }
+}

Sources/OpenSwiftUI_SPI/Shims/QuartzCore/CAFilterPrivate.h

@@ -9,6 +9,7 @@
 
 #if __has_include(<QuartzCore/CoreAnimation.h>)
 
+#include <OpenRenderBoxShims/OpenRenderBoxShims.h>
 #import <QuartzCore/CoreAnimation.h>
 
 OPENSWIFTUI_ASSUME_NONNULL_BEGIN
@@ -66,6 +67,9 @@ OPENSWIFTUI_EXPORT id _Nullable _CAFilterGetInput(CAFilter *filter, CAFilterInpu
 OPENSWIFTUI_EXPORT void _CAFilterSetInput(CAFilter * _Nullable filter, id _Nullable value, CAFilterInputKey key) OPENSWIFTUI_SWIFT_NAME(CAFilter.setInput(self:value:key:));
 OPENSWIFTUI_EXPORT NSMutableArray<CAFilter *> *_CAFilterArrayCreate(void) OPENSWIFTUI_SWIFT_NAME(CAFilterArrayCreate());
 OPENSWIFTUI_EXPORT void _CAFilterArrayAppend(NSMutableArray<CAFilter *> *array, CAFilter *filter) OPENSWIFTUI_SWIFT_NAME(CAFilterArrayAppend(_:_:));
+OPENSWIFTUI_EXPORT id _Nullable _ORBBlendModeGetCompositingFilter(ORBBlendMode blendMode, bool compositingGroup) OPENSWIFTUI_SWIFT_NAME(ORBBlendModeGetCompositingFilter(_:compositingGroup:));
+// Returns normal for nil and -1 for an unrecognized filter name.
+OPENSWIFTUI_EXPORT ORBBlendMode _CACompositingFilterGetORBBlendMode(id _Nullable filter) OPENSWIFTUI_SWIFT_NAME(CACompositingFilterGetORBBlendMode(_:));
 
 OPENSWIFTUI_ASSUME_NONNULL_END