# linear Linear pacing, which causes an animation to occur evenly over its duration. ``` static let linear: CAMediaTimingFunctionName ``` ## Discussion This is a Bézier timing function with the control points (0.0,0.0) and (1.0,1.0). The following code shows how to create a basic animation object using linear interpolation. ```swift let verticalAnimation = CABasicAnimation(keyPath: "position.y") verticalAnimation.fromValue = 310 verticalAnimation.toValue = 10 verticalAnimation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear) ``` A layer animated with the animation created by the code above and with linearly interpolated horizontal movement would describe a path similar to the following figure.  --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)