Add support for customizing gradient values using GradientValueProvider

Sources/Private/CoreAnimation/Animations/LayerProperty.swift

@@ -62,7 +62,10 @@ struct CustomizableProperty<ValueRepresentation> {
 
   /// A closure that coverts the type-erased value of an `AnyValueProvider`
   /// to the strongly-typed representation used by this property, if possible.
-  let conversion: (Any) -> ValueRepresentation?
+  ///  - `value` is the value for the current frame that should be converted,
+  ///    as returned by `AnyValueProvider.typeErasedStorage`.
+  ///  - `valueProvider` is the `AnyValueProvider` that returned the type-erased value.
+  let conversion: (_ value: Any, _ valueProvider: AnyValueProvider) -> ValueRepresentation?
 }
 
 // MARK: - PropertyName
@@ -77,6 +80,7 @@ enum PropertyName: String, CaseIterable {
   case position = "Position"
   case rotation = "Rotation"
   case strokeWidth = "Stroke Width"
+  case gradientColors = "Colors"
 }
 
 // MARK: CALayer properties
@@ -260,14 +264,14 @@ extension LayerProperty {
     .init(
       caLayerKeypath: #keyPath(CAGradientLayer.colors),
       defaultValue: nil,
-      customizableProperty: nil /* currently unsupported */ )
+      customizableProperty: .gradientColors)
   }
 
   static var locations: LayerProperty<[CGFloat]> {
     .init(
       caLayerKeypath: #keyPath(CAGradientLayer.locations),
       defaultValue: nil,
-      customizableProperty: nil /* currently unsupported */ )
+      customizableProperty: .gradientLocations)
   }
 
   static var startPoint: LayerProperty<CGPoint> {
@@ -291,7 +295,7 @@ extension CustomizableProperty {
   static var color: CustomizableProperty<CGColor> {
     .init(
       name: [.color],
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let color = typeErasedValue as? LottieColor else {
           return nil
         }
@@ -303,7 +307,7 @@ extension CustomizableProperty {
   static var opacity: CustomizableProperty<CGFloat> {
     .init(
       name: [.opacity],
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let vector = typeErasedValue as? LottieVector1D else { return nil }
 
         // Lottie animation files express opacity as a numerical percentage value
@@ -316,7 +320,7 @@ extension CustomizableProperty {
   static var scaleX: CustomizableProperty<CGFloat> {
     .init(
       name: [.scale],
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let vector = typeErasedValue as? LottieVector3D else { return nil }
 
         // Lottie animation files express scale as a numerical percentage value
@@ -329,7 +333,7 @@ extension CustomizableProperty {
   static var scaleY: CustomizableProperty<CGFloat> {
     .init(
       name: [.scale],
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let vector = typeErasedValue as? LottieVector3D else { return nil }
 
         // Lottie animation files express scale as a numerical percentage value
@@ -342,7 +346,7 @@ extension CustomizableProperty {
   static var rotation: CustomizableProperty<CGFloat> {
     .init(
       name: [.rotation],
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let vector = typeErasedValue as? LottieVector1D else { return nil }
 
         // Lottie animation files express rotation in degrees
@@ -355,13 +359,34 @@ extension CustomizableProperty {
   static var position: CustomizableProperty<CGPoint> {
     .init(
       name: [.position],
-      conversion: { ($0 as? LottieVector3D)?.pointValue })
+      conversion: { typeErasedValue, _ in
+        guard let vector = typeErasedValue as? LottieVector3D else { return nil }
+        return vector.pointValue
+      })
+  }
+
+  static var gradientColors: CustomizableProperty<[CGColor]> {
+    .init(
+      name: [.gradientColors],
+      conversion: { _, typeErasedValueProvider in
+        guard let gradientValueProvider = typeErasedValueProvider as? GradientValueProvider else { return nil }
+        return gradientValueProvider.colors.map { $0.cgColorValue }
+      })
+  }
+
+  static var gradientLocations: CustomizableProperty<[CGFloat]> {
+    .init(
+      name: [.gradientColors],
+      conversion: { _, typeErasedValueProvider in
+        guard let gradientValueProvider = typeErasedValueProvider as? GradientValueProvider else { return nil }
+        return gradientValueProvider.locations.map { CGFloat($0) }
+      })
   }
 
   static func floatValue(_ name: PropertyName...) -> CustomizableProperty<CGFloat> {
     .init(
       name: name,
-      conversion: { typeErasedValue in
+      conversion: { typeErasedValue, _ in
         guard let vector = typeErasedValue as? LottieVector1D else { return nil }
         return vector.cgFloatValue
       })

Sources/Private/CoreAnimation/ValueProviderStore.swift

@@ -73,9 +73,11 @@ final class ValueProviderStore {
 
     // Convert the type-erased keyframe values using this `CustomizableProperty`'s conversion closure
     let typedKeyframes = typeErasedKeyframes.compactMap { typeErasedKeyframe -> Keyframe<Value>? in
-      guard let convertedValue = customizableProperty.conversion(typeErasedKeyframe.value) else {
+      guard let convertedValue = customizableProperty.conversion(typeErasedKeyframe.value, anyValueProvider) else {
         logger.assertionFailure("""
-          Could not convert value of type \(type(of: typeErasedKeyframe.value)) to expected type \(Value.self)
+          Could not convert value of type \(type(of: typeErasedKeyframe.value)) from \(anyValueProvider) to expected type \(
+          Value
+          .self)
           """)
         return nil
       }

Sources/Private/MainThread/NodeRenderSystem/Nodes/RenderNodes/GradientFillNode.swift

@@ -27,7 +27,7 @@ final class GradientFillProperties: NodePropertyMap, KeypathSearchable {
       PropertyName.opacity.rawValue : opacity,
       "Start Point" : startPoint,
       "End Point" : endPoint,
-      "Colors" : colors,
+      PropertyName.gradientColors.rawValue : colors,
     ]
     properties = Array(keypathProperties.values)
   }

Sources/Private/MainThread/NodeRenderSystem/Nodes/RenderNodes/GradientStrokeNode.swift

@@ -47,7 +47,7 @@ final class GradientStrokeProperties: NodePropertyMap, KeypathSearchable {
       PropertyName.opacity.rawValue : opacity,
       "Start Point" : startPoint,
       "End Point" : endPoint,
-      "Colors" : colors,
+      PropertyName.gradientColors.rawValue : colors,
       PropertyName.strokeWidth.rawValue : width,
       "Dashes" : dashPattern,
       "Dash Phase" : dashPhase,

Sources/Public/DynamicProperties/ValueProviders/GradientValueProvider.swift

@@ -69,16 +69,18 @@ public final class GradientValueProvider: ValueProvider {
   }
 
   public var storage: ValueProviderStorage<[Double]> {
-    .closure { [self] frame in
-      hasUpdate = false
+    if let block = block {
+      return .closure { [self] frame in
+        hasUpdate = false
 
-      if let block = block {
         let newColors = block(frame)
         let newLocations = locationsBlock?(frame) ?? []
         value = value(from: newColors, locations: newLocations)
-      }
 
-      return value
+        return value
+      }
+    } else {
+      return .singleValue(value)
     }
   }
 
@@ -129,7 +131,9 @@ public final class GradientValueProvider: ValueProvider {
 
 }
 
-extension GradientValueProvider {
+// MARK: Equatable
+
+extension GradientValueProvider: Equatable {
   public static func ==(_ lhs: GradientValueProvider, _ rhs: GradientValueProvider) -> Bool {
     lhs.identity == rhs.identity
   }

Sources/Public/DynamicProperties/ValueProviders/PointValueProvider.swift

@@ -74,7 +74,9 @@ public final class PointValueProvider: ValueProvider {
   private let identity: AnyHashable
 }
 
-extension PointValueProvider {
+// MARK: Equatable
+
+extension PointValueProvider: Equatable {
   public static func ==(_ lhs: PointValueProvider, _ rhs: PointValueProvider) -> Bool {
     lhs.identity == rhs.identity
   }

Sources/Public/DynamicProperties/ValueProviders/SizeValueProvider.swift

@@ -74,7 +74,9 @@ public final class SizeValueProvider: ValueProvider {
   private let identity: AnyHashable
 }
 
-extension SizeValueProvider {
+// MARK: Equatable
+
+extension SizeValueProvider: Equatable {
   public static func ==(_ lhs: SizeValueProvider, _ rhs: SizeValueProvider) -> Bool {
     lhs.identity == rhs.identity
   }

Tests/Samples/Issues/issue_1854.json

@@ -0,0 +1 @@
+{"v":"5.7.4","fr":60,"ip":0,"op":68,"w":450,"h":450,"nm":"GX_fab_rings","ddd":0,"assets":[],"layers":[{"ddd":0,"ind":1,"ty":4,"nm":".accent","cl":"accent","sr":1,"ks":{"o":{"a":1,"k":[{"i":{"x":[0.667],"y":[1]},"o":{"x":[0.333],"y":[0]},"t":0,"s":[0]},{"i":{"x":[0.667],"y":[1]},"o":{"x":[0.333],"y":[0]},"t":16,"s":[100]},{"i":{"x":[0.724],"y":[1]},"o":{"x":[0.305],"y":[0]},"t":32,"s":[80]},{"i":{"x":[0.833],"y":[1]},"o":{"x":[0.42],"y":[0]},"t":52,"s":[80]},{"t":66,"s":[0]}],"ix":11},"r":{"a":0,"k":-45,"ix":10},"p":{"a":0,"k":[225,225,0],"ix":2,"l":2},"a":{"a":0,"k":[0,0,0],"ix":1,"l":2},"s":{"a":1,"k":[{"i":{"x":[0.537,0.537,0.667],"y":[1.001,1.001,1]},"o":{"x":[0.333,0.333,0.333],"y":[0,0,0]},"t":0,"s":[13.667,13.667,100]},{"i":{"x":[0.538,0.538,0.667],"y":[0.938,0.938,1]},"o":{"x":[0.586,0.586,0.333],"y":[0.015,0.015,0]},"t":16,"s":[90.667,90.667,100]},{"i":{"x":[0.472,0.472,0.667],"y":[1.057,1.057,1]},"o":{"x":[0.264,0.264,0.333],"y":[-0.013,-0.013,0]},"t":32,"s":[67.712,67.712,100]},{"i":{"x":[0.667,0.667,0.667],"y":[1,1,1]},"o":{"x":[0.333,0.333,0.333],"y":[0,0,0]},"t":50,"s":[74.667,74.667,100]},{"i":{"x":[0.284,0.284,0.667],"y":[1,1,1]},"o":{"x":[0.333,0.333,0.333],"y":[0,0,0]},"t":52,"s":[74.667,74.667,100]},{"t":66,"s":[5.667,5.667,100]}],"ix":6,"l":2}},"ao":0,"shapes":[{"ty":"gr","it":[{"d":1,"ty":"el","s":{"a":0,"k":[450,450],"ix":2},"p":{"a":0,"k":[0,0],"ix":3},"nm":"Ellipse Path 1","mn":"ADBE Vector Shape - Ellipse","hd":false},{"ty":"tr","p":{"a":0,"k":[0,0],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[100,100],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k":0,"ix":4},"sa":{"a":0,"k":0,"ix":5},"nm":"Transform"}],"nm":"Ellipse 1","np":1,"cix":2,"bm":0,"ix":1,"mn":"ADBE Vector Group","hd":false},{"ty":"gf","o":{"a":0,"k":100,"ix":10},"r":1,"bm":0,"g":{"p":3,"k":{"a":0,"k":[0,0.98,0.118,0.306,0.5,0.98,0.118,0.306,1,0.98,0.118,0.306,0,1,0.5,0.75,1,0.5],"ix":9}},"s":{"a":0,"k":[0,-180],"ix":5},"e":{"a":0,"k":[0,212],"ix":6},"t":1,"nm":"Gradient Fill 1","mn":"ADBE Vector Graphic - G-Fill","hd":false}],"ip":0,"op":68,"st":0,"bm":0}],"markers":[]}

Tests/SnapshotConfiguration.swift

@@ -97,6 +97,16 @@ extension SnapshotConfiguration {
       AnimationKeypath(keypath: "**.base_color.**.Color"): ColorValueProvider(.black),
     ]),
 
+    "Issues/issue_1854": .customValueProviders([
+      AnimationKeypath(keypath: "**.Colors"): GradientValueProvider(
+        [
+          LottieColor(r: 0, g: 0, b: 0, a: 0),
+          LottieColor(r: 1, g: 1, b: 1, a: 0.5),
+          LottieColor(r: 1, g: 1, b: 1, a: 1),
+        ],
+        locations: [0, 0.3, 1.0]),
+    ]),
+
     "Issues/issue_1847": .customValueProviders([
       AnimationKeypath(keypath: "**.Stroke 1.**.Color"): ColorValueProvider(.red),
     ]),

Tests/__Snapshots__/AutomaticEngineTests/testAutomaticEngineDetection.Issues-issue_1854.txt

@@ -0,0 +1 @@
+Supports Core Animation engine