# init(columns:rows:sourcePositions:destinationPositions:) Creates a warp geometry grid of a specific size and warp translation, in point arrays. ``` convenience init(columns: Int, rows: Int, sourcePositions: [SIMD2] = [SIMD2](), destinationPositions: [SIMD2] = [SIMD2]()) ``` ## Parameters `columns` The number of columns in the grid. `rows` The number of rows in the grid. `sourcePositions` Optionally included array of the grid’s source warp positions. `destinationPositions` Optionally included array of the grid’s destination warp positions. ## Return Value A new warp geometry grid object. ## Discussion You supply the source and destination position as row-major arrays of normalized coordinates. The number of horizontal coordinates is the column count plus one and the number of vertical coordinates is the row count plus one. Passing `nil` as either of the position arguments results in an identity warp with vertices distributed evenly throughout the geometry. Passing `nil` to both `sourcePositions` and `destPositions` gives a result identical to [`init(columns:rows:)`](/documentation/SpriteKit/SKWarpGeometryGrid/init(columns:rows:)). --- 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)