# init(position:stiffness:) Creates a position constraint with the given target position and stiffness. ``` init(position: SIMD3, stiffness: Float) ``` ## Parameters `position` The target position to pull the particle towards. `stiffness` The stiffness with which the particle is pulled towards `position`. --- 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)