# distortionShader(_:maxSampleOffset:) Returns a filter that applies `shader` as a geometric distortion effect on the location of each pixel. ``` static func distortionShader(_ shader: Shader, maxSampleOffset: CGSize) -> GraphicsContext.Filter ``` ## Parameters `shader` The shader to apply as a distortion effect. `maxSampleOffset` The maximum distance in each axis between the returned source pixel position and the destination pixel position, for all source pixels. ## Return Value A new filter that applies the shader as a distortion effect. ## Discussion For a shader function to act as a distortion effect it must have a function signature matching: ``` [[ stitchable ]] float2 name(float2 position, args...) ``` where `position` is the user-space coordinates of the destination pixel applied to the shader. `args...` should be compatible with the uniform arguments bound to `shader`. The function should return the user-space coordinates of the corresponding source pixel. --- 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)