Fix linux platform build issue

Author: Kyle-Ye

Sources/OpenSwiftUICore/Extension/CGAffineTransform+Extension.swift

@@ -5,9 +5,48 @@
 //  Audited for iOS 18.0
 //  Status: Complete
 
-#if canImport(Darwin)
-
+#if canImport(CoreGraphics)
 package import CoreGraphics
+#else
+package import Foundation
+// FIXME: Use Silica or other implementation
+public struct CGAffineTransform: Equatable {
+    public init() {
+        a = .zero
+        b = .zero
+        c = .zero
+        d = .zero
+        tx = .zero
+        ty = .zero
+    }
+
+    public init(a: Double, b: Double, c: Double, d: Double, tx: Double, ty: Double) {
+        self.a = a
+        self.b = b
+        self.c = c
+        self.d = d
+        self.tx = tx
+        self.ty = ty
+    }
+    
+    public var a: Double
+    public var b: Double
+    public var c: Double
+    public var d: Double
+    public var tx: Double
+    public var ty: Double
+    
+    public static let identity = CGAffineTransform(a: 1, b: 0, c: 0, d: 1, tx: 0, ty: 0)
+    
+    public func concatenating(_ transform: CGAffineTransform) -> CGAffineTransform {
+        preconditionFailure("Unimplemented")
+    }
+    
+    public func inverted() -> CGAffineTransform {
+        preconditionFailure("Unimplemented")
+    }
+}
+#endif
 
 extension CGAffineTransform {
     package init(rotation: Angle) {
@@ -78,5 +117,3 @@ extension CGAffineTransform: ProtobufMessage {
         self = transform
     }
 }
-
-#endif

Sources/OpenSwiftUICore/Layout/Geometry/ProjectionTransform.swift

@@ -8,25 +8,6 @@
 public import Foundation
 #if canImport(QuartzCore)
 public import QuartzCore
-#else
-// FIXME: Use Silica or other implementation
-public struct CGAffineTransform {
-    public init()
-
-    public init(a: Double, b: Double, c: Double, d: Double, tx: Double, ty: Double)
-
-    public var a: Double
-
-    public var b: Double
-
-    public var c: Double
-
-    public var d: Double
-
-    public var tx: Double
-
-    public var ty: Double
-}
 #endif
 
 @frozen
@@ -200,7 +181,6 @@ extension CGPoint {
     }
 }
 
-#if canImport(QuartzCore)
 extension CGAffineTransform {
     package init(_ m: ProjectionTransform) {
         self.init(
@@ -211,6 +191,7 @@ extension CGAffineTransform {
     }
 }
 
+#if canImport(QuartzCore)
 extension CATransform3D {
     package init(_ m: ProjectionTransform) {
         self.init(

Sources/OpenSwiftUICore/Layout/View/ViewTransform.swift

@@ -705,8 +705,12 @@ extension [CGPoint]: ApplyViewTransform, ViewTransformable {
             case let .translation(offset):
                 self = map { $0 + offset }
             case let .affineTransform(matrix, inverse):
+                #if canImport(CoreGraphics)
                 let tranform = inverse ? matrix.inverted() : matrix
                 self = map { $0.applying(tranform) }
+                #else
+                preconditionFailure("CGAffineTransform+applying is not available on this platform")
+                #endif
             case let .projectionTransform(matrix, inverse):
                 apply(matrix, inverse: inverse)
             case .coordinateSpace, .sizedSpace, .scrollGeometry: