# fill(buffer:range:value:) Encodes a command that fills a buffer with a constant value for each byte. ``` func fill(buffer: any MTLBuffer, range: Range, value: UInt8) ``` ## Parameters `buffer` A buffer instance the command assigns each byte in `range` to `value`. `range` A range of bytes within the `buffer` the command assigns `value` to. The range’s property needs to be greater than `0`. The range’s , , and properties need to be a multiple of `4` in macOS, but can be any value in iOS and tvOS. `value` The value to write to each byte. --- 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)