SpringTimingParameters
The timing information for animations that mimics the behavior of a spring.
public class SpringTimingParameters 
Initializers
  init() 
 Creates a default timing parameters object.
public init() 
This method sets the initial velocity of any animated properties to 0.0 and sets the damping ratio to 4.56.
  init(dampingRatio:) 
 Creates a timing parameters object with the specified damping ratio.
public convenience init(dampingRatio ratio: Double) 
This method sets the initial velocity of any animated properties to 0.0.
  init(dampingRatio:initialVelocity:) 
 Creates a timing parameters object with the specified damping ratio and initial velocity.
public init(dampingRatio ratio: Double, initialVelocity velocity: Vector) 
  init(mass:stiffness:damping:initialVelocity:) 
 Creates a timing parameters object with the specified spring stiffness, mass, damping coefficient, and initial velocity.
public init(mass: Double, stiffness: Double, damping: Double,
              initialVelocity velocity: Vector) 
The damping ratio for the spring is computed from the formula: damping / (2 * sqrt (stiffness * mass)).
Properties
  initialVelocity 
 The target property’s rate of change at the start of a spring animation, enabling a smooth transition into the animation.
public private(set) var initialVelocity: Vector