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README.md

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+![](./previews/og-image.png)
+
+# Pow
+
+Delightful SwiftUI transitions for your app.
+
+> **Note**
+> This is a Beta version.
+>
+> Pow is free while in Beta and will be a simple one-time purchase after that.
+
+# Installation
+
+To add a package dependency to your Xcode project, select _File_ > _Add Package_ and enter this repository's URL (https://github.com/movingparts-io/Pow).
+
+# Known issues
+
+- [Xcode Previews depending on Pow are broken in Xcode 14b5](https://developer.apple.com/forums/thread/707569).  
+  **Suggested Solution:** Download, unpack and embed the [`.xcframework` referenced in the `Package.swift`](./Package.swift) file.
+
+# Overview
+
+All transitions are namespaced under the `movingParts` static variable, e.g.
+
+```swift
+myView.transition(.movingParts.anvil)
+```
+
+## Anvil
+
+![A view dropping down like an avil, hitting the ground in a cloud of dust.](./previews/anvil.mov)
+
+A transition that drops the view down from the top.
+
+The transition is only performed on insertion and takes 1.4 seconds.
+
+```swift
+static var anvil: AnyTransition
+```
+
+## Blur 
+
+A transition from blurry to sharp on insertion, and from sharp to blurry
+on removal.
+
+```swift
+static var blur: AnyTransition
+```
+
+## Boing
+
+![A view dropping down, deforming as it hits its resing position as if made from jelly.](./previews/boing.mov)
+
+A transition that moves the view down with any overshoot resulting in an
+elastic deformation of the view.
+
+```swift
+static var boing: AnyTransition
+```
+
+A transition that moves the view away towards the specified edge, with
+any overshoot resulting in an elastic deformation of the view.
+
+```swift
+static func boing(edge: Edge) -> AnyTransition
+```
+
+## Clock
+
+A transition using a clockwise sweep around the centerpoint of the view.
+
+```swift
+static var clock: AnyTransition
+```
+
+A transition using a clockwise sweep around the centerpoint of the view.
+
+- Parameter `blurRadius`: The radius of the blur applied to the mask.
+
+```swift
+static func clock(blurRadius: CGFloat)  -> AnyTransition
+```
+
+## Flicker
+
+A transition that toggles the visibility of the view multiple times
+before settling.
+
+```swift
+static var flicker: AnyTransition
+```
+
+A transition that toggles the visibility of the view multiple times
+before settling.
+
+- Parameter `count`: The number of times the visibility is toggled.
+
+```swift
+static func flicker(count: Int) -> AnyTransition
+```
+
+## Flip
+
+![A view rotating into view.](./previews/flip.mov)
+
+A transition that inserts by rotating the view towards the viewer, and
+removes by rotating the view away from the viewer.
+
+> **Note:**
+> Any overshoot of the animation will result in the view continuing the rotation past the view's normal state before eventually settling.
+
+```swift
+static var flip: AnyTransition
+```
+
+## Glare
+
+A transitions that shows the view by combining a diagonal wipe with a
+white streak.
+
+```swift
+static var glare: AnyTransition
+```
+
+A transitions that shows the view by combining a wipe with a colored
+streak.
+
+The angle is relative to the current `layoutDirection`, such that 0°
+represents sweeping towards the leading edge on insertion and 90°
+represents sweeping towards the top edge.
+
+In this example, the removal of the view is using a glare with an
+exponential ease-in curve, combined with a anticipating scale animation,
+making for a more dramatic exit.
+
+![A view that appears with a white steak and disappears with the same streak, combined with a rising up animation.](./previews/glare.mov)
+
+```swift
+infoBox
+  .transition(
+    .asymmetric(
+      insertion: .movingParts.glare(angle: .degrees(225)),
+      removal: .movingParts.glare(angle: .degrees(45)
+    )
+    .animation(.movingParts.easeInExponential(duration: 0.9))
+        .combined(with:
+          .scale(scale: 1.4)
+            .animation(.movingParts.anticipate(duration: 0.9).delay(0.1)
+        )
+      )
+    )
+  )
+```
+
+- Parameters:
+  - `direction`: The angle of the wipe.
+  - `color`: The color of the glare effect.
+
+```swift
+static func glare(angle: Angle, color: Color = .white) -> AnyTransition
+```
+
+## Iris
+
+A transition that takes the shape of a growing circle when inserting,
+and a shrinking circle when removing.
+
+- Parameters:
+  - `origin`: The center point of the circle as it grows or shrinks.
+  - `blurRadius`: The radius of the blur applied to the mask.
+
+```swift
+static func iris(origin: UnitPoint = .center, blurRadius: CGFloat = 0) -> AnyTransition
+```
+
+## Move
+
+A transition that moves the view from the specified edge of the on
+insertion and towards it on removal.
+
+```swift
+static func move(edge: Edge) -> AnyTransition
+```
+
+A transition that moves the view at the specified angle.
+
+The angle is relative to the current `layoutDirection`, such that 0° represents animating towards the leading edge on insertion and 90° represents inserting towards the top edge.
+
+In this example, the view insertion is animated by moving it towards the top trailing corner and the removal is animated by moving it towards the bottom edge.
+
+```swift
+Text("Hello")
+  .transition(
+    .asymmetric(
+      insertion: .movingParts.move(angle: .degrees(45)),
+      removal:   .movingParts.move(angle: .degrees(90))
+    )
+  )
+```
+
+- Parameter `angle`: The direction of the animation.
+
+```swift
+static func move(angle: Angle) -> AnyTransition
+```
+
+## Pop
+
+![A view that appears following a ripple effect and colored particles.](./previews/pop.mov)
+
+A transition that shows a view with a ripple effect and a flurry of
+tint-colored particles.
+
+The transition is only performed on insertion and takes 1.2 seconds.
+
+```swift
+static var pop: AnyTransition
+```
+
+A transition that shows a view with a ripple effect and a flurry of
+colored particles.
+
+In this example, the star uses the pop effect only when transitioning
+from `starred == false` to `starred == true`:
+
+```swift
+Button {
+  starred.toggle()
+} label: {
+  if starred {
+    Image(systemName: "star.fill")
+      .foregroundStyle(.orange)
+      .transition(.movingParts.pop(.orange))
+  } else {
+    Image(systemName: "star")
+      .foregroundStyle(.gray)
+      .transition(.identity)
+  }
+}
+```
+
+The transition is only performed on insertion.
+
+- Parameter `style`: The style to use for the effect.
+
+```swift
+static func pop(_ style: AnyShapeStyle) -> AnyTransition
+```
+
+## Rotate3D
+
+A transition that inserts by rotating from the specified rotation, and
+removes by rotating to the specified rotation in three dimensions.
+
+In this example, the view is rotated 90˚ about the y axis around
+its bottom edge as if it was rising from lying on its back face:
+
+![A view that raises up from lying on its back, overshooting as it does.](./previews/rotate3d.mov)
+
+```swift
+Text("Hello")
+  .transition(.movingParts.rotate3D(
+    .degrees(90),
+      axis: (1, 0, 0),
+      anchor: .bottom,
+      perspective: 1.0 / 6.0)
+  )
+```
+
+> **Note:**
+> Any overshoot of the animation will result in the view continuing the rotation past the view's normal state before eventually settling.
+
+- Parameters:
+  - `angle`: The angle from which to rotate the view.
+  - `axis`: The x, y and z elements that specify the axis of rotation.
+  - `anchor`: The location with a default of center that defines a point
+            in 3D space about which the rotation is anchored.
+  - `anchorZ`: The location with a default of 0 that defines a point in 3D
+             space about which the rotation is anchored.
+  - `perspective`: The relative vanishing point with a default of 1 for
+                 this rotation.
+
+```swift
+static func rotate3D(_ angle: Angle, axis: (x: CGFloat, y: CGFloat, z: CGFloat), anchor: UnitPoint = .center, anchorZ: CGFloat = 0, perspective: CGFloat = 1) -> AnyTransition
+```
+
+## Skid
+
+![A sliding in from the left, overshowing and deforming as it moves.](./previews/skid.mov)
+
+A transition that moves the view in from its leading edge with any
+overshoot resulting in an elastic deformation of the view.
+
+```swift
+static var skid: AnyTransition
+```
+
+A transition that moves the view in from the specified edge during
+insertion and towards it during removal with any overshoot resulting
+in an elastic deformation of the view.
+
+- Parameter `direction`: The direction of the transition.
+
+```swift
+static func skid(direction: SkidDirection) -> AnyTransition
+```
+
+## Swoosh
+
+A three-dimensional transition from the back of the towards the front
+during insertion and from the front towards the back during removal.
+
+```swift
+static var swoosh: AnyTransition
+```
+
+## Vanish
+
+![A view that dissolves into many small particles.](./previews/vanish.mov)
+
+A transition that dissolves the view into many small particles.
+
+The transition is only performed on removal.
+
+```swift
+static var vanish: AnyTransition
+```
+
+## Wipe
+
+A transition using a sweep from the specified edge on insertion, and
+towards it on removal.
+
+- Parameters:
+  - `edge`: The edge at which the sweep starts or ends.
+  - `blurRadius`: The radius of the blur applied to the mask.
+
+```swift
+static func wipe(edge: Edge, blurRadius: CGFloat = 0) -> AnyTransition
+```