Update lottie-ios

submodules/lottie-ios/Sources/Public/Keyframes/Interpolatable.swift

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+// Created by Cal Stephens on 1/24/22.
+// Copyright © 2022 Airbnb Inc. All rights reserved.
+
+import CoreGraphics
+
+// MARK: - Interpolatable
+
+/// A type that can be interpolated between two values
+public protocol Interpolatable: AnyInterpolatable {
+  /// Interpolates the `self` to the given number by `amount`.
+  ///  - Parameter to: The number to interpolate to.
+  ///  - Parameter amount: The amount to interpolate,
+  ///    relative to 0.0 (self) and 1.0 (to).
+  ///    `amount` can be greater than one and less than zero,
+  ///    and interpolation should not be clamped.
+  ///
+  ///  ```
+  ///  let number = 5
+  ///  let interpolated = number.interpolateTo(10, amount: 0.5)
+  ///  print(interpolated) // 7.5
+  ///  ```
+  ///
+  ///  ```
+  ///  let number = 5
+  ///  let interpolated = number.interpolateTo(10, amount: 1.5)
+  ///  print(interpolated) // 12.5
+  ///  ```
+  func interpolate(to: Self, amount: CGFloat) -> Self
+}
+
+// MARK: - SpatialInterpolatable
+
+/// A type that can be interpolated between two values,
+/// additionally using optional `spatialOutTangent` and `spatialInTangent` values.
+///  - If your implementation doesn't use the `spatialOutTangent` and `spatialInTangent`
+///    parameters, prefer implementing the simpler `Interpolatable` protocol.
+public protocol SpatialInterpolatable: AnyInterpolatable {
+  /// Interpolates the `self` to the given number by `amount`.
+  ///  - Parameter to: The number to interpolate to.
+  ///  - Parameter amount: The amount to interpolate,
+  ///    relative to 0.0 (self) and 1.0 (to).
+  ///    `amount` can be greater than one and less than zero,
+  ///    and interpolation should not be clamped.
+  func interpolate(
+    to: Self,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> Self
+}
+
+// MARK: - AnyInterpolatable
+
+/// The base protocol that is implemented by both `Interpolatable` and `SpatialInterpolatable`
+/// Types should not directly implement this protocol.
+public protocol AnyInterpolatable {
+  /// Interpolates by calling either `Interpolatable.interpolate`
+  /// or `SpatialInterpolatable.interpolate`.
+  /// Should not be implemented or called by consumers.
+  func _interpolate(
+    to: Self,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> Self
+}
+
+extension Interpolatable {
+  public func _interpolate(
+    to: Self,
+    amount: CGFloat,
+    spatialOutTangent _: CGPoint?,
+    spatialInTangent _: CGPoint?)
+    -> Self
+  {
+    interpolate(to: to, amount: amount)
+  }
+}
+
+extension SpatialInterpolatable {
+  /// Helper that interpolates this `SpatialInterpolatable`
+  /// with `nil` spatial in/out tangents
+  public func interpolate(to: Self, amount: CGFloat) -> Self {
+    interpolate(
+      to: to,
+      amount: amount,
+      spatialOutTangent: nil,
+      spatialInTangent: nil)
+  }
+
+  public func _interpolate(
+    to: Self,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> Self
+  {
+    interpolate(
+      to: to,
+      amount: amount,
+      spatialOutTangent: spatialOutTangent,
+      spatialInTangent: spatialInTangent)
+  }
+}
+
+// MARK: - Double + Interpolatable
+
+extension Double: Interpolatable { }
+
+// MARK: - CGFloat + Interpolatable
+
+extension CGFloat: Interpolatable { }
+
+// MARK: - Float + Interpolatable
+
+extension Float: Interpolatable { }
+
+extension Interpolatable where Self: BinaryFloatingPoint {
+  public func interpolate(to: Self, amount: CGFloat) -> Self {
+    self + ((to - self) * Self(amount))
+  }
+}
+
+// MARK: - CGRect + Interpolatable
+
+extension CGRect: Interpolatable {
+  public func interpolate(to: CGRect, amount: CGFloat) -> CGRect {
+    CGRect(
+      x: origin.x.interpolate(to: to.origin.x, amount: amount),
+      y: origin.y.interpolate(to: to.origin.y, amount: amount),
+      width: width.interpolate(to: to.width, amount: amount),
+      height: height.interpolate(to: to.height, amount: amount))
+  }
+}
+
+// MARK: - CGSize + Interpolatable
+
+extension CGSize: Interpolatable {
+  public func interpolate(to: CGSize, amount: CGFloat) -> CGSize {
+    CGSize(
+      width: width.interpolate(to: to.width, amount: amount),
+      height: height.interpolate(to: to.height, amount: amount))
+  }
+}
+
+// MARK: - CGPoint + SpatialInterpolatable
+
+extension CGPoint: SpatialInterpolatable {
+  public func interpolate(
+    to: CGPoint,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> CGPoint
+  {
+    guard
+      let outTan = spatialOutTangent,
+      let inTan = spatialInTangent
+    else {
+      return CGPoint(
+        x: x.interpolate(to: to.x, amount: amount),
+        y: y.interpolate(to: to.y, amount: amount))
+    }
+
+    let cp1 = self + outTan
+    let cp2 = to + inTan
+    return interpolate(to, outTangent: cp1, inTangent: cp2, amount: amount)
+  }
+}
+
+// MARK: - Color + Interpolatable
+
+extension Color: Interpolatable {
+  public func interpolate(to: Color, amount: CGFloat) -> Color {
+    Color(
+      r: r.interpolate(to: to.r, amount: amount),
+      g: g.interpolate(to: to.g, amount: amount),
+      b: b.interpolate(to: to.b, amount: amount),
+      a: a.interpolate(to: to.a, amount: amount))
+  }
+}
+
+// MARK: - Vector1D + Interpolatable
+
+extension Vector1D: Interpolatable {
+  public func interpolate(to: Vector1D, amount: CGFloat) -> Vector1D {
+    value.interpolate(to: to.value, amount: amount).vectorValue
+  }
+}
+
+// MARK: - Vector2D + SpatialInterpolatable
+
+extension Vector2D: SpatialInterpolatable {
+  public func interpolate(
+    to: Vector2D,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> Vector2D
+  {
+    pointValue.interpolate(
+      to: to.pointValue,
+      amount: amount,
+      spatialOutTangent: spatialOutTangent,
+      spatialInTangent: spatialInTangent)
+      .vector2dValue
+  }
+}
+
+// MARK: - Vector3D + SpatialInterpolatable
+
+extension Vector3D: SpatialInterpolatable {
+  public func interpolate(
+    to: Vector3D,
+    amount: CGFloat,
+    spatialOutTangent: CGPoint?,
+    spatialInTangent: CGPoint?)
+    -> Vector3D
+  {
+    if spatialInTangent != nil || spatialOutTangent != nil {
+      // TODO Support third dimension spatial interpolation
+      let point = pointValue.interpolate(
+        to: to.pointValue,
+        amount: amount,
+        spatialOutTangent: spatialOutTangent,
+        spatialInTangent: spatialInTangent)
+
+      return Vector3D(
+        x: point.x,
+        y: point.y,
+        z: CGFloat(z.interpolate(to: to.z, amount: amount)))
+    }
+
+    return Vector3D(
+      x: x.interpolate(to: to.x, amount: amount),
+      y: y.interpolate(to: to.y, amount: amount),
+      z: z.interpolate(to: to.z, amount: amount))
+  }
+}
+
+// MARK: - Array + Interpolatable, AnyInterpolatable
+
+extension Array: Interpolatable, AnyInterpolatable where Element: Interpolatable {
+  public func interpolate(to: [Element], amount: CGFloat) -> [Element] {
+    LottieLogger.shared.assert(
+      count == to.count,
+      "When interpolating Arrays, both array sound have the same element count.")
+
+    return zip(self, to).map { lhs, rhs in
+      lhs.interpolate(to: rhs, amount: amount)
+    }
+  }
+}